記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/15389588.2018.1533247

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The crush energy is a key parameter to determine the delta-V in accident reconstructions. Since an accurate car crush profile can be obtained from 3D scanners, this research aims at validating the methods currently used in calculating crush energy from a crush profile. For this validation, a finite element (FE) car model was analyzed using various types of impact conditions to investigate the theory of energy-based accident reconstruction.<br />Two methods exist to calculate the crush energy: the work based on the barrier force and the work based on force calculated by the vehicle acceleration times the vehicle mass. We show that the crush energy calculated from the barrier force was substantially larger than the internal energy calculated from the FE model. Whereas the crush energy calculated from the vehicle acceleration was comparable to the internal energy of the FE model.<br />In full frontal impact simulations, the energy of approach factor (EAF) has a linear relation with the residual crush, which had been validated in previous experimental studies. In our study using FE analysis, we found that the slope of EAF versus the residual crush was comparable with that of the dynamic crush en

DOI： 10.4271/09-06-02-0009

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier Ltd  

Analyzing a crash using driving recorder data makes it possible to objectively examine factors contributing to the occurrence of the crash. In this study, car-to-cyclist crashes and near crashes recorded on cars equipped with advanced driving recorders were compared with each other in order to examine the factors that differentiate near crashes from crashes, as well as identify the causes of the crashes. Focusing on cases where the car and cyclist approached each other perpendicularly, the differences in the car's and cyclist's parameters such as velocity, distance and avoidance behavior were analyzed. The results show that car-to-cyclist crashes would not be avoidable when the car approaching the cyclist enters an area where the average deceleration required to stop the car is more than 0.45 G (4.4 m/s2). In order for this situation to occur, there are two types of cyclist crash scenarios. In the first scenario, the delay in the drivers’ reaction in activating the brakes is the main factor responsible for the crash. In this scenario, time-to-collision when the cyclist first appears in the video is more than 2.0 s. In the second scenario, the sudden appearance of a cyclist from behind an obstacle on the street is the factor responsible for the crash. In this case, the time-to-collision is less than 1.2 s, and the crash cannot be avoided even if the driver exhibited avoidance maneuvers.

DOI： 10.1016/j.aap.2018.03.029

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

In car accidents, components and restraint systems around the occupant can cause severe injuries to the abdomen area. Damage to the liver, the largest internal organ, can result in large amounts of bleeding, leading to fatal injuries. In this study, a liver model with internal blood vessels was developed and validated by dynamic compression ex vivo. Then, impact tests were conducted on a full-body human finite element model containing the liver. Finally, a side impact collision was simulated with the human model seated in the car, and liver deformation as well as internal injury caused by the blood were investigated.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TAYLOR & FRANCIS LTD  

In vehicle-cyclist collisions, the head of cyclists impacts frequently against the windshield and the A-pillar of the vehicle. Accident analyses show that the head injury risk is high in impacts with stiff A-pillars. In this research, the head protection with cyclist helmets in impacts against the A-pillar was investigated from experiments and finite element (FE) analyses. The headform impact tests were conducted using the pedestrian headform with and without a cyclist helmet. In the A-pillar impact at 35 km/h, the HIC reduced substantially from without helmet (4815) to with helmet (3000) though it was far above the injury acceptance level (1000). The head protection by helmets in impacts against A-pillars might be limited because of high impact velocities of the head and A-pillar stiffness. The FE simulations of the headform impacts indicated that the helmet liner deformed locally and bottomed-out in the A-pillar impacts, whereas the A-pillar deformation was small. In the FE analysis of a human head model with a capping helmet, the skull fracture did not occur but the brain strain was large. From a simple model of the head acceleration in the A-pillar impact, it was shown that the helmet liner has little effect on the HIC, whereas a deforming A-pillar with a force level of 5-7kN could reduce the HIC of the head with helmets less than 1500.

DOI： 10.1080/13588265.2016.1259952

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TAYLOR & FRANCIS LTD  

The chest deflection and chest acceleration (3 ms) have been used as chest injury measures of Hybrid III dummy in frontal crash tests. In this research, the relationship between two chest injury measures was investigated based on finite element analysis of Hybrid III in a frontal impact. The equation of motion of the chest was established using the external (seatbelt force and airbag contact force) and internal forces (neck, shoulder joint, lumbar spine force) that are exert on the chest. Based on this formula, the mechanism of the chest acceleration that was generated can be examined with time. The chest deflection is related to the external forces (seatbelt and airbag force), and the chest acceleration is related to the external and internal forces. The influence that the restraint conditions (seatbelt path and force limiter) has on the chest acceleration and chest deflection was also investigated. The seatbelt path affected the rib cage deformation mode and the chest sternum deflection, but it has little effect of on the chest acceleration. Lowering the seatbelt force limiter value also reduced the chest deflection substantially, but it did not show any clear relationship with the chest acceleration since the kinematics and the internal forces of the Hybrid III dummy changed with varying force limiter values.

DOI： 10.1080/13588265.2016.1215587

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TAYLOR & FRANCIS INC  

Objective: In car crashes, the passenger compartment deceleration significantly influences the occupant loading. Hence, it is important to consider how each structural component deforms in order to control the passenger compartment deceleration. In frontal impact tests, the passenger compartment deceleration depends on the energy absorption property of the front structures. However, at this point in time there are few papers describing the components' quantitative contributions on the passenger compartment deceleration. Generally, the cross-sectional force is used to examine each component's contribution to passenger compartment deceleration. However, it is difficult to determine each component's contribution based on the cross-sectional forces, especially within segments of the individual members itself such as the front rails, because the force is transmitted continuously and the cross-sectional forces remain the same through the component.Method: The deceleration of a particle can be determined from the derivative of the kinetic energy. Using this energy-derivative method, the contribution of each component on the passenger compartment deceleration can be determined. Using finite element (FE) car models, this method was applied for full-width and offset impact tests. This method was also applied to evaluate the deceleration of the powertrain. The finite impulse response (FIR) coefficient of the vehicle deceleration (input) and the driver chest deceleration (output) was calculated from Japan New Car Assessment Program (JNCAP) tests. These were applied to the component's contribution on the vehicle deceleration in FE analysis, and the component's contribution to the deceleration of the driver's chest was determined.Result: The sum of the contribution of each component coincides with the passenger compartment deceleration in all types of impacts; therefore, the validity of this method was confirmed. In the full-width impact, the contribution of the crush box was large in the initial phases, and the contribution of the passenger compartment was large in the final phases. For the powertrain deceleration, the crush box had a positive contribution and the passenger compartment had a negative contribution. In the offset test, the contribution of the honeycomb and the passenger compartment deformation to the passenger compartment deceleration was large. Based on the FIR analysis, the passenger compartment deformation contributed the most to the chest deceleration of the driver dummy in the full-width impact.Conclusions: Based on the energy-derivative method, the contribution of the components' deformation to deceleration of the passenger compartment can be calculated for various types of crash configurations more easily, directly, and quantitatively than by using conventional methods. In addition, by combining the energy-derivative method and FIR, each structure's contribution to the occupant deceleration can be obtained. The energy-derivative method is useful in investigating how the deceleration develops from component deformations and also in designing deceleration curves for various impact configurations.

DOI： 10.1080/15389588.2017.1296957

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 自動車技術会  

自動車と歩行者の交通事故で，自動ブレーキによる歩行者の頭部の傷害軽減を検討した．多くの場合，自動ブレーキは車の速度低下に有効だが，自動ブレーキによって歩行者の頭部がAピラーに衝突し，傷害が悪化する場合がある．そこでAピラー衝突が発生する条件を求めた．

DOI： 10.11351/jsaeronbun.48.399

CiNii Books

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

The method of calculating the head trajectory in three dimensions within the passenger compartment using the head and vehicle&#039;s acceleration and angular velocity in their respective local coordinate systems was constructed. To verify this calculation method, a crash simulation in LS-DYNA was conducted to compare the calculated result and the simulated result. The possibility of obtaining the head trajectory in the global coordinate system from the head and vehicle&#039;s acceleration and angular velocity in their respective local coordinate systems using LS-DYNA and MADYMO was also investigated. The head trajectory of a vehicle occupant with respect to the vehicle as well as the global coordinate system can be obtained using these methods.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：自動車技術会  

A cyclist takes different postures of lower extremities while pushing the pedals. In this research, the kinematics of the whole body and injury risk of cyclist were examined for three representative postures of the lower extremities with and without cyclist traveling velocity. The knee height of the cyclist relative to the hood leading edge affected the kinematics and the head impact location against the car. The bicycle velocity influenced not only head impact location in the car lateral direction but also knee deformation.

CiNii Books

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

本研究では，日本外傷データバンクで収集された外傷データから日本の歩行者および自転車乗員の外傷の傾向を明らかにすることを目的とする．特に歩行者事故および自転車乗車中の事故で頻発する頭部および下肢の外傷発生状況を年齢層別，性別に解析し，その特徴について検討した．<br />歩行者および自転車乗車中の事故では頭部外傷の発生頻度が高いことは従来の事故統計と同様の結果であったのに対し，下肢傷害では，これまで自動車側での保護対策が十分におこなわれていない骨盤での損傷の発生頻度が高いことがわかった．自転車乗車中の事故では大腿骨骨折の占める割合が高くなり，事故状況の違いが受傷部位に影響を及ぼすことが示された．さらに，両事故形態ともに加齢に伴い出血性脳損傷の増加や大腿骨頚部での骨折割合の増加など，外傷の種類や発生箇所が変化することが明らかとなった．

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：自動車技術会  

The objective of this study is to understand the effects of car rotation on occupant kinematic behavior in vehicle impact with rotation. The method to provide the boundary condition for the occupants under car acceleration and rotation was formulated. Small overlap frontal crash (yawing), full-width crash (pitching) and offset impact tests (yawing and pitching) were examined by FE model simulations. The vehicle yaw motions had a small effect on the occupant kinematics. The vehicle pitch motions mitigated the loading on occupants in a frontal crash since the anchor of the seatbelt moved with vehicle pitch rotation, which increased ridedown of the occupant.

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TAYLOR & FRANCIS INC  

Objective: A cyclist assumes various cyclic postures of the lower extremities while pushing the pedals in a rotary motion while pedaling. In order to protect cyclists in collisions, it is necessary to understand what influence these postures have on the global kinematics and injuries of the cyclist.Method: Finite element (FE) analyses using models of a cyclist, bicycle, and car were conducted. In the simulations, the Total Human Model of Safety (THUMS) occupant model was employed as a cyclist, and the simulation was set up such that the cyclist was hit from its side by a car. Three representative postures of the lower extremities of the cyclist were examined, and the kinematics and injury risk of the cyclist were compared to those obtained by a pedestrian FE model. The risk of a lower extremity injury was assessed based on the knee shear displacement and the tibia bending moment.Results: When the knee position of the cyclist was higher than the hood leading edge, the hood leading edge contacted the leg of the cyclist, and the pelvis slid over the hood top and the wrap-around distance (WAD) of the cyclist's head was large. The knee was shear loaded by the hood leading edge, and the anterior cruciate ligament (ACL) ruptured. The tibia bending moment was less than the injury threshold. When the cyclist's knee position was lower than the hood leading edge, the hood leading edge contacted the thigh of the cyclist, and the cyclist rotated with the femur as the pivot point about the hood leading edge. In this case, the head impact location of the cyclist against the car was comparable to that of the pedestrian collision. The knee shear displacement and the tibia bending moment were less than the injury thresholds.Conclusion: The knee height of the cyclist relative to the hood leading edge affected the global kinematics and the head impact location against the car. The loading mode of the lower extremities was also dependent on the initial positions of the lower extremities relative to the car structures. In the foot up and front posture, the knee was loaded in a lateral shear direction by the hood leading edge and as a result the ACL ruptured. The bicycle frame and the struck-side lower extremity interacted and could influence the loadings on lower extremities.

DOI： 10.1080/15389588.2015.1126671

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：自動車技術会  

Chest deflection and acceleration of crash dummy have been used as chest injury measures in frontal crash test. In this research, mechanism and relation of the two chest injury measures were investigated. The seat belt path and force limiter load were changed to clarify the effects on the chest injury by Hybrid III dummy and human finite element models. The chest acceleration was derived from external and internal joint force and the effect of seatbelt path was small, whereas the chest deflection was affected by the seatbelt force and the seatbelt path.

CiNii Books

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：自動車技術会  

Cyclists are frequently injured head and lower extremities in car-to-cyclist collisions. In this research, kinematic behavior of the whole body and the interaction of car, cyclist and bicycle were numerically investigated using a simulation with an FE simulation. Kinematic behavior of a cyclist was similar to that of a pedestrian, but the pelvis and head movement were different due to difference of posture of the lower extremities. Cyclist&#039;s tibia impacted to hood leading edge and shear loading was applied in the cyclist&#039;s knee, which can cause knee injury.

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TAYLOR & FRANCIS INC  

Objective: Vehicle deceleration has a large influence on occupant kinematic behavior and injury risks in crashes, and the optimization of the vehicle crash pulse that mitigates occupant loadings has been the subject of substantial research. These optimization research efforts focused on only high-velocity impact in regulatory or new car assessment programs though vehicle collisions occur over a wide range of velocities. In this study, the vehicle crash pulse was optimized for various velocities with a genetic algorithm.
Method: Vehicle deceleration was optimized in a full-frontal rigid barrier crash with a simple spring-mass model that represents the vehicle-occupant interaction and a Hybrid III 50th percentile male multibody model.
To examine whether the vehicle crash pulse optimized at the high impact velocity is useful for reducing occupant loading at all impact velocities less than the optimized velocity, the occupant deceleration was calculated at various velocities for the optimized crash pulse determined at a high speed.
The optimized vehicle deceleration-deformation characteristics that are effective for various velocities were investigated with 2 approaches.
Results: The optimized vehicle crash pulse at a single impact velocity consists of a high initial impulse followed by zero deceleration and then constant deceleration in the final stage. The vehicle deceleration optimized with the Hybrid III model was comparable to that determined from the spring-mass model.
The optimized vehicle deceleration-deformation characteristics determined at a high speed did not necessarily lead to an occupant deceleration reduction at a lower velocity.
The maximum occupant deceleration at each velocity was normalized by the maximum deceleration determined in the single impact velocity optimization. The resulting vehicle deceleration-deformation characteristic was a square crash pulse. The objective function was defined as the number of injuries, which was the product of the number of collisions at the velocity and the probability of occupant injury. The optimized vehicle deceleration consisted of a high deceleration in the initial phase, a small deceleration in the middle phase, and then a high deceleration in the final phase.
Conclusion: The optimized vehicle crash pulse at a single impact velocity is effective for reducing occupant deceleration in a crash at the specific impact velocity. However, the crash pulse does not necessarily lead to occupant deceleration reduction at a lower velocity. The optimized vehicle deceleration-deformation characteristics, which are effective for all impact velocities, depend on the weighting of the occupant injury measures at each impact velocity.

DOI： 10.1080/15389588.2014.937805

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：自動車技術会  

The head protection with cyclist helmets in impacts against the A-pillar was investigated from experiments and finite element (FE) analyses. In the A-pillar impact tests at 35 km/h, the HIC was above the injury acceptance level even with helmet. The FE simulations of the headform impacts indicated that the helmet liner deformed locally, whereas the A-pillar deformation was small. In the FE analysis of a human head model with a helmet, the skull fracture did not occur but the brain strain was large. From a simple model of the head acceleration, the helmet liner characteristics has a little effect on the HIC at high velocity impacts.

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

The head is the body region that most frequently incurs fatal and serious injuries of cyclists in collisions against vehicles. Many research studies investigated helmet effectiveness in preventing head injuries using accident data. In this study, the impact attenuation characteristics of three Japanese child bicycle helmets were examined experimentally in impact tests into a concrete surface and a vehicle. A pedestrian adult headform with and without a Japanese child bicycle helmet was dropped onto a concrete surface and then propelled into a vehicle at 35 km/h in various locations such as the bonnet, roof header, windshield and A-pillar. Accelerations were measured and head injury criterion (HIC) calculated. In the drop tests using the adult headform onto a concrete surface from the height of 1.5 m, the HIC for a headform without a child helmet was 6325, and was reduced by around 80% when a child helmet was fitted to the headform. In the impact tests, where the headform was fired into the vehicle at 35 km/h at various locations on a car, the computed acceleration based HIC varied depending on the vehicle impact locations. The HIC was reduced by 10-38% for impacts headforms with a child helmet when the impact was onto a bonnet-top and roof header although the HIC was already less than 1000 in impacts with the headform without a child helmet. Similarly, for impacts into the windshield (where a cyclist's head is most frequently impacted), the HIC using the adult headform without a child helmet was 122; whereas when the adult headform was used with a child helmet, a higher HIC value of more than 850 was recorded. But again, the HIC values are below 1000. In impacts into the A-pillar, the HIC was 4816 for a headform without a child helmet and was reduced by 18-38% for a headform with a child helmet depending on the type of Japanese child helmet used. The tests demonstrated that Japanese child helmets are effective in reducing accelerations and HIC in a drop test using an adult headform onto a relatively rigid hard surface, i.e., simulating a road surface or concrete path. However, when the impact tests are into softer surfaces, the child helmet's capacity to decrease accelerations is accordingly reduced. Impacts into the windshield, while below the critical HIC value of 1000, indicated higher HIC values for a headform with a child helmet compared to an adult headform without a child helmet. The unpredictable nature of the results indicates further research work is required to assess how representative the stiffness of an adult headform is when compared to an actual head. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.aap.2014.09.018

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TAYLOR & FRANCIS INC  

Objective: In vehicle frontal impacts, vehicle acceleration has a large effect on occupant loadings and injury risks. In this research, an optimal vehicle crash pulse was determined systematically to reduce injury measures of rear seat occupants by using mathematical simulations.
Method: The vehicle crash pulse was optimized based on a vehicle deceleration-deformation diagram under the conditions that the initial velocity and the maximum vehicle deformation were constant. Initially, a spring-mass model was used to understand the fundamental parameters for optimization. In order to investigate the optimization under a more realistic situation, the vehicle crash pulse was also optimized using a multibody model of a Hybrid III dummy seated in the rear seat for the objective functions of chest acceleration and chest deflection. A sled test using a Hybrid III dummy was carried out to confirm the simulation results. Finally, the optimal crash pulses determined from the multibody simulation were applied to a human finite element (FE) model.
Results: The optimized crash pulse to minimize the occupant deceleration had a concave shape: a high deceleration in the initial phase, low in the middle phase, and high again in the final phase. This crash pulse shape depended on the occupant restraint stiffness. The optimized crash pulse determined from the multibody simulation was comparable to that from the spring-mass model. From the sled test, it was demonstrated that the optimized crash pulse was effective for the reduction of chest acceleration. The crash pulse was also optimized for the objective function of chest deflection. The optimized crash pulse in the final phase was lower than that obtained for the minimization of chest acceleration. In the FE analysis of the human FE model, the optimized pulse for the objective function of the Hybrid III chest deflection was effective in reducing rib fracture risks.
Conclusions: The optimized crash pulse has a concave shape and is dependent on the occupant restraint stiffness and maximum vehicle deformation. The shapes of the optimized crash pulse in the final phase were different for the objective functions of chest acceleration and chest deflection due to the inertial forces of the head and upper extremities. From the human FE model analysis it was found that the optimized crash pulse for the Hybrid III chest deflection can substantially reduce the risk of rib cage fractures. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.

DOI： 10.1080/15389588.2013.792408

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本交通科学学会  

自動車乗員が拘束装置からの負荷によって胸部に加速度が発生する状況をin vivo動物モデルにて再現できる実験系を構築することを目的として，ラットを用いた落下試験を実施し，加速度変化に対する胸部応答を評価した．さらに，人体においても類似の応答が得られることを確認するため，人体有限要素モデルを用いた衝撃シミュレーションを実施した．ラットの胸骨加速度は複数のピークを持つ波形となり，その最大値はほぼテーブル加速度の設定値と一致した．また，脊柱加速度は若干胸骨加速度より遅れて発生した．この傾向は人体有限要素モデルにおいても確認された．ラットの実験結果と人体有限要素モデルのシミュレーション結果を比較するため，幾何学的相似性を仮定してスケーリングを行ったところ，胸骨加速度に関してはほぼ同等の応答が得られた．小型動物モデルでもスケーリングを行うことで，人体の胸郭剛性の評価を補完・代替できる可能性が示された．

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TAYLOR & FRANCIS LTD  

An active bonnet and pedestrian airbag are effective in providing a high level of pedestrian head protection. For triggering the activation of these systems, a reliable sensor that distinguishes a pedestrian collision from collisions against other colliding objects is necessary. In this research, a pedestrian contact sensor based on the pressure of a deformable chamber was investigated from finite-element (FE) analysis. In a simulation of a component test of a chamber impact, the internal pressure of the chamber increased with the volume deformation of the chamber according to Boyle's law. The chamber was installed above the top plane of the bumper energy absorber of a simple car model, and FE simulations of a car-pedestrian collision were conducted. The chamber deformed and its internal pressure increased as the bumper energy absorber deformed during contact with the pedestrian leg. It was shown that the pressure response of the chamber could be detected, irrespective of vehicle shape and structure. This particular pressure response in pedestrian collisions was different from that in collisions into other objects such as a road pole. The contact force of the bumper energy absorber tends to be linear with the pressure change of the chamber. It was shown that a pedestrian collision can be distinguished with high reliability from other colliding objects using the chamber pressure based on the colliding characteristics depending on each colliding object.

DOI： 10.1080/13588265.2014.917493

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

To discuss the mechanism of muscle strain injury from biomechanical viewpoints, the change of mechanical properties of injured skeletal muscle was evaluated experimentally. We induced strain injury to rabbit tibialis anterior muscle by applying a single tension loading/unloading process under the conditions of various stretch amplitude, stretch rate, and muscle activation in situ. The results showed that isometric contractile force decreased with increasing stretch amplitude during the injury-induction process. Multiple regression analyses were conducted for the results and they showed that the stretch amplitude played a dominant role in the decrease of the contractility. The failure stress decreased significantly with the increasing stretch amplitude and dissipation energy during the injury-induction process. Moreover, the failure stresses of the muscle injured under unstimulated conditions obviously decreased in comparison with those of the muscles in intact and injured under stimulated conditions. On the basis of these results and previous experimental studies, we concluded that muscle activity played a significant roll to prevent the decrease of the failure stress and that the damage mechanism of strain injury depended on the muscle activity during injury-induction process. © 2012 by JSME.

DOI： 10.1299/jbse.7.156

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The purpose of this study is to develop a constitutive model of skeletal muscle that describes material anisotropy, viscoelasticity and damage of muscle tissue. A free energy function is described as the sum of volumetric elastic, isochoric elastic and isochoric viscoelastic parts. The isochoric elastic part is divided into two types of shear response and the response in the fiber direction. To represent the dependence of the mechanical properties on muscle activity, we incorporate a contractile element into the model. The viscoelasticity of muscle is modeled as a three-dimensional model constructed by extending the one-dimensional generalized Maxwell model. Based on the framework of continuum damage mechanics, the anisotropic damage of muscle tissue is expressed by a second-order damage tensor. The evolution of the damage is assumed to depend on the current strain and damage. The evolution equation is formulated using the representation theorem of tensor functions. The proposed model is applied to the experimental data on tensile mechanical properties in the fiber direction and the compression properties in the fiber and cross-fiber directions in literature. The model can predict non-linear mechanical properties and breaking points. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jmbbm.2009.05.001

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掲載種別：研究論文（国際会議プロシーディングス）  

Scopus

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

In car crashes, the passenger compartment deceleration significantly influences the occupant loading. In this study, a calculation method to determine the structural components&#039; contribution on the car deceleration, called energy-derivative method, was proposed. Using this energy-derivative method, the contribution of each component on the passenger compartment deceleration can be determined. Using finite element car models, this method was applied for full-width and offset impact tests.<br />
The sum of the contribution of each component coincides with the passenger compartment deceleration in all types of impacts; therefore, the validity of this method was confirmed. In the full-width impact, the contribution of the crush box was large in the initial phases, and the contribution of the passenger compartment was large in the final phases. <br />
Based on the energy-derivative method, the contribution of the components&#039; deformation to deceleration of the passenger compartment can be calculated for various types of crash configurations more easily, directly, and quantitatively than by using conventional methods.

DOI： 10.1080/15389588.2017.1296957

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：TAYLOR & FRANCIS LTD  

In vehicle-cyclist collisions, the head of cyclists impacts frequently against the windshield and the A-pillar of the vehicle. Accident analyses show that the head injury risk is high in impacts with stiff A-pillars. In this research, the head protection with cyclist helmets in impacts against the A-pillar was investigated from experiments and finite element (FE) analyses. The headform impact tests were conducted using the pedestrian headform with and without a cyclist helmet. In the A-pillar impact at 35 km/h, the HIC reduced substantially from without helmet (4815) to with helmet (3000) though it was far above the injury acceptance level (1000). The head protection by helmets in impacts against A-pillars might be limited because of high impact velocities of the head and A-pillar stiffness. The FE simulations of the headform impacts indicated that the helmet liner deformed locally and bottomed-out in the A-pillar impacts, whereas the A-pillar deformation was small. In the FE analysis of a human head model with a capping helmet, the skull fracture did not occur but the brain strain was large. From a simple model of the head acceleration in the A-pillar impact, it was shown that the helmet liner has little effect on the HIC, whereas a deforming A-pillar with a force level of 5-7kN could reduce the HIC of the head with helmets less than 1500.

DOI： 10.1080/13588265.2016.1259952

Web of Science

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：公益社団法人 自動車技術会  

自動車と歩行者の交通事故で，自動ブレーキによる歩行者の頭部の傷害軽減を検討した．多くの場合，自動ブレーキは車の速度低下に有効だが，自動ブレーキによって歩行者の頭部がAピラーに衝突し，傷害が悪化する場合がある．そこでAピラー衝突が発生する条件を求めた．

DOI： 10.11351/jsaeronbun.48.399

CiNii Books

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

The method of calculating the head trajectory in three dimensions within the passenger compartment using the head and vehicle&#039;s acceleration and angular velocity in their respective local coordinate systems was constructed. To verify this calculation method, a crash simulation in LS-DYNA was conducted to compare the calculated result and the simulated result. The possibility of obtaining the head trajectory in the global coordinate system from the head and vehicle&#039;s acceleration and angular velocity in their respective local coordinate systems using LS-DYNA and MADYMO was also investigated. The head trajectory of a vehicle occupant with respect to the vehicle as well as the global coordinate system can be obtained using these methods.

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記述言語：日本語  

J-GLOBAL

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

The chest deflection and chest acceleration (3 ms) have been used as chest injury measures of Hybrid III dummy in frontal crash tests. In this research, the relationship between two chest injury measures was investigated based on finite element analysis of Hybrid III in a frontal impact. The equation of motion of the chest was established using the external (seatbelt force and airbag contact force) and internal forces (neck, shoulder joint, lumbar spine force) that are exert on the chest. The chest deflection is related to the external forces, and the chest acceleration is related to the external and internal forces. The influence that the restraint conditions (seatbelt path and force limiter) has on the chest acceleration and chest deflection was also investigated. The seatbelt path affected the rib cage deformation mode and the chest sternum deflection, but it has little effect of on the chest acceleration. Lowering the seatbelt force limiter value also reduced the chest deflection substantially, but it did not show any clear relationship with the chest acceleration since the kinematics and the internal forces of the Hybrid III dummy changed with varying force limiter values.

DOI： 10.1080/13588265.2016.1215587

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：自動車技術会  

A cyclist takes different postures of lower extremities while pushing the pedals. In this research, the kinematics of the whole body and injury risk of cyclist were examined for three representative postures of the lower extremities with and without cyclist traveling velocity. The knee height of the cyclist relative to the hood leading edge affected the kinematics and the head impact location against the car. The bicycle velocity influenced not only head impact location in the car lateral direction but also knee deformation.

CiNii Books

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

In order to protect cyclists in collisions, it is necessary to understand what influence these postures have on the global kinematics and injuries of the cyclist.<br />
Finite element (FE) analyses using models of a cyclist, bicycle, and car were conducted. The simulation was set up such that the cyclist was hit from its side by a car. Three representative postures of the lower extremities of the cyclist were examined. The risk of a lower extremity injury was assessed based on the knee shear displacement and the tibia bending moment.<br />
The knee height of the cyclist relative to the hood leading edge affected the global kinematics and the head impact location against the car. The loading mode of the lower extremities was also dependent on the initial positions of the lower extremities relative to the car structures. In the foot up and front posture, the knee was loaded in a lateral shear direction by the hood leading edge and as a result the ACL ruptured. The bicycle frame and the struck-side lower extremity interacted and could influence the loadings on lower extremities.

DOI： 10.1080/15389588.2015.1126671

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：日本交通科学学会  

本研究では，日本外傷データバンクで収集された外傷データから日本の歩行者および自転車乗員の外傷の傾向を明らかにすることを目的とする．特に歩行者事故および自転車乗車中の事故で頻発する頭部および下肢の外傷発生状況を年齢層別，性別に解析し，その特徴について検討した．<br />
歩行者および自転車乗車中の事故では頭部外傷の発生頻度が高いことは従来の事故統計と同様の結果であったのに対し，下肢傷害では，これまで自動車側での保護対策が十分におこなわれていない骨盤での損傷の発生頻度が高いことがわかった．自転車乗車中の事故では大腿骨骨折の占める割合が高くなり，事故状況の違いが受傷部位に影響を及ぼすことが示された．さらに，両事故形態ともに加齢に伴い出血性脳損傷の増加や大腿骨頚部での骨折割合の増加など，外傷の種類や発生箇所が変化することが明らかとなった．

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その他リンク： http://search.jamas.or.jp/link/ui/2016168404

記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：自動車技術会  

The objective of this study is to understand the effects of car rotation on occupant kinematic behavior in vehicle impact with rotation. The method to provide the boundary condition for the occupants under car acceleration and rotation was formulated. Small overlap frontal crash (yawing), full-width crash (pitching) and offset impact tests (yawing and pitching) were examined by FE model simulations. The vehicle yaw motions had a small effect on the occupant kinematics. The vehicle pitch motions mitigated the loading on occupants in a frontal crash since the anchor of the seatbelt moved with vehicle pitch rotation, which increased ridedown of the occupant.

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：自動車技術会  

Chest deflection and acceleration of crash dummy have been used as chest injury measures in frontal crash test. In this research, mechanism and relation of the two chest injury measures were investigated. The seat belt path and force limiter load were changed to clarify the effects on the chest injury by Hybrid III dummy and human finite element models. The chest acceleration was derived from external and internal joint force and the effect of seatbelt path was small, whereas the chest deflection was affected by the seatbelt force and the seatbelt path.

CiNii Books

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：自動車技術会  

Cyclists are frequently injured head and lower extremities in car-to-cyclist collisions. In this research, kinematic behavior of the whole body and the interaction of car, cyclist and bicycle were numerically investigated using a simulation with an FE simulation. Kinematic behavior of a cyclist was similar to that of a pedestrian, but the pelvis and head movement were different due to difference of posture of the lower extremities. Cyclist&#039;s tibia impacted to hood leading edge and shear loading was applied in the cyclist&#039;s knee, which can cause knee injury.

CiNii Books

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

Objective: Vehicle deceleration has a large influence on occupant kinematic behavior and injury risks in crashes, and the optimization of the vehicle crash pulse that mitigates occupant loadings has been the subject of substantial research. These optimization research efforts focused on only high-velocity impact in regulatory or new car assessment programs though vehicle collisions occur over a wide range of velocities. In this study, the vehicle crash pulse was optimized for various velocities with a genetic algorithm.Method: Vehicle deceleration was optimized in a full-frontal rigid barrier crash with a simple spring-mass model that represents the vehicle-occupant interaction and a Hybrid III 50th percentile male multibody model.To examine whether the vehicle crash pulse optimized at the high impact velocity is useful for reducing occupant loading at all impact velocities less than the optimized velocity, the occupant deceleration was calculated at various velocities for the optimized crash pulse determined at a high speed.The optimized vehicle deceleration-deformation characteristics that are effective for various velocities were investigated with 2 approaches.Results: The optimized vehicle crash pulse at a single impact velocity consists of a high initial impulse followed by zero deceleration and then constant deceleration in the final stage. The vehicle deceleration optimized with the Hybrid III model was comparable to that determined from the spring-mass model.The optimized vehicle deceleration-deformation characteristics determined at a high speed did not necessarily lead to an occupant deceleration reduction at a lower velocity.The maximum occupant deceleration at each velocity was normalized by the maximum deceleration determined in the single impact velocity optimization. The resulting vehicle deceleration-deformation characteristic was a square crash pulse. The objective function was defined as the number of injuries, which was the product of the number of collisions at the velocity and the probability of occupant injury. The optimized vehicle deceleration consisted of a high deceleration in the initial phase, a small deceleration in the middle phase, and then a high deceleration in the final phase.Conclusion: The optimized vehicle crash pulse at a single impact velocity is effective for reducing occupant deceleration in a crash at the specific impact velocity. However, the crash pulse does not necessarily lead to occupant deceleration reduction at a lower velocity. The optimized vehicle deceleration-deformation characteristics, which are effective for all impact velocities, depend on the weighting of the occupant injury measures at each impact velocity.

DOI： 10.1080/15389588.2014.937805

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：自動車技術会  

The head protection with cyclist helmets in impacts against the A-pillar was investigated from experiments and finite element (FE) analyses. In the A-pillar impact tests at 35 km/h, the HIC was above the injury acceptance level even with helmet. The FE simulations of the headform impacts indicated that the helmet liner deformed locally, whereas the A-pillar deformation was small. In the FE analysis of a human head model with a helmet, the skull fracture did not occur but the brain strain was large. From a simple model of the head acceleration, the helmet liner characteristics has a little effect on the HIC at high velocity impacts.

CiNii Books

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

自動車乗員が拘束装置からの負荷によって胸部に加速度が発生する状況をin vivo動物モデルにて再現できる実験系を構築することを目的として，ラットを用いた落下試験を実施し，加速度変化に対する胸部応答を評価した．さらに，人体においても類似の応答が得られることを確認するため，人体有限要素モデルを用いた衝撃シミュレーションを実施した．ラットの胸骨加速度は複数のピークを持つ波形となり，その最大値はほぼテーブル加速度の設定値と一致した．また，脊柱加速度は若干胸骨加速度より遅れて発生した．この傾向は人体有限要素モデルにおいても確認された．ラットの実験結果と人体有限要素モデルのシミュレーション結果を比較するため，幾何学的相似性を仮定してスケーリングを行ったところ，胸骨加速度に関してはほぼ同等の応答が得られた．小型動物モデルでもスケーリングを行うことで，人体の胸郭剛性の評価を補完・代替できる可能性が示された．

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

The head is the body region that most frequently incurs fatal and serious injuries of cyclists in collisions against vehicles. Many research studies investigated helmet effectiveness in preventing head injuries using accident data. In this study, the impact attenuation characteristics of three Japanese child bicycle helmets were examined experimentally in impact tests into a concrete surface and a vehicle. A pedestrian adult headform with and without a Japanese child bicycle helmet was dropped onto a concrete surface and then propelled into a vehicle at 35 km/h in various locations such as the bonnet, roof header, windshield and A-pillar. Accelerations were measured and head injury criterion (HIC) calculated. In the drop tests using the adult headform onto a concrete surface from the height of 1.5 m, the HIC for a headform without a child helmet was 6325, and was reduced by around 80% when a child helmet was fitted to the headform. In the impact tests, where the headform was fired into the vehicle at 35 km/h at various locations on a car, the computed acceleration based HIC varied depending on the vehicle impact locations. The HIC was reduced by 10-38% for impacts headforms with a child helmet when the impact was onto a bonnet-top and roof header although the HIC was already less than 1000 in impacts with the headform without a child helmet. Similarly, for impacts into the windshield (where a cyclist's head is most frequently impacted), the HIC using the adult headform without a child helmet was 122; whereas when the adult headform was used with a child helmet, a higher HIC value of more than 850 was recorded. But again, the HIC values are below 1000. In impacts into the A-pillar, the HIC was 4816 for a headform without a child helmet and was reduced by 18-38% for a headform with a child helmet depending on the type of Japanese child helmet used. The tests demonstrated that Japanese child helmets are effective in reducing accelerations and HIC in a drop test using an adult headform onto a relatively rigid hard surface, i.e., simulating a road surface or concrete path. However, when the impact tests are into softer surfaces, the child helmet's capacity to decrease accelerations is accordingly reduced. Impacts into the windshield, while below the critical HIC value of 1000, indicated higher HIC values for a headform with a child helmet compared to an adult headform without a child helmet. The unpredictable nature of the results indicates further research work is required to assess how representative the stiffness of an adult headform is when compared to an actual head. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.aap.2014.09.018

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

In this research, a pedestrian contact sensor based on the pressure of a deformable chamber was investigated from finite-element (FE) analysis. In a simulation of a component test of a chamber impact, the internal pressure of the chamber increased with the volume deformation of the chamber according to Boyle&#039;s law. The chamber was installed above the top plane of the bumper energy absorber of a simple car model, and FE simulations of a car-pedestrian collision were conducted. The chamber deformed and its internal pressure increased as the bumper energy absorber deformed during contact with the pedestrian leg. It was shown that the pressure response of the chamber could be detected, irrespective of vehicle shape and structure. This particular pressure response in pedestrian collisions was different from that in collisions into other objects such as a road pole. The contact force of the bumper energy absorber tends to be linear with the pressure change of the chamber. It was shown that a pedestrian collision can be distinguished with high reliability from other colliding objects using the chamber pressure based on the colliding characteristics depending on each colliding object.

DOI： 10.1080/13588265.2014.917493

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

Objective: In vehicle frontal impacts, vehicle acceleration has a large effect on occupant loadings and injury risks. In this research, an optimal vehicle crash pulse was determined systematically to reduce injury measures of rear seat occupants by using mathematical simulations.Method: The vehicle crash pulse was optimized based on a vehicle deceleration-deformation diagram under the conditions that the initial velocity and the maximum vehicle deformation were constant. Initially, a spring-mass model was used to understand the fundamental parameters for optimization. In order to investigate the optimization under a more realistic situation, the vehicle crash pulse was also optimized using a multibody model of a Hybrid III dummy seated in the rear seat for the objective functions of chest acceleration and chest deflection. A sled test using a Hybrid III dummy was carried out to confirm the simulation results. Finally, the optimal crash pulses determined from the multibody simulation were applied to a human finite element (FE) model.Results: The optimized crash pulse to minimize the occupant deceleration had a concave shape: a high deceleration in the initial phase, low in the middle phase, and high again in the final phase. This crash pulse shape depended on the occupant restraint stiffness. The optimized crash pulse determined from the multibody simulation was comparable to that from the spring-mass model. From the sled test, it was demonstrated that the optimized crash pulse was effective for the reduction of chest acceleration. The crash pulse was also optimized for the objective function of chest deflection. The optimized crash pulse in the final phase was lower than that obtained for the minimization of chest acceleration. In the FE analysis of the human FE model, the optimized pulse for the objective function of the Hybrid III chest deflection was effective in reducing rib fracture risks.Conclusions: The optimized crash pulse has a concave shape and is dependent on the occupant restraint stiffness and maximum vehicle deformation. The shapes of the optimized crash pulse in the final phase were different for the objective functions of chest acceleration and chest deflection due to the inertial forces of the head and upper extremities. From the human FE model analysis it was found that the optimized crash pulse for the Hybrid III chest deflection can substantially reduce the risk of rib cage fractures. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.

DOI： 10.1080/15389588.2013.792408

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

DOI： 10.1299/jbse.7.156

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記述言語：日本語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）  

The purpose of this study is to develop a constitutive model of skeletal muscle that describes material anisotropy, viscoelasticity and damage of muscle tissue. A free energy function is described as the sum of volumetric elastic, isochoric elastic and isochoric viscoelastic parts. The isochoric elastic part is divided into two types of shear response and the response in the fiber direction. To represent the dependence of the mechanical properties on muscle activity, we incorporate a contractile element into the model. The viscoelasticity of muscle is modeled as a three-dimensional model constructed by extending the one-dimensional generalized Maxwell model. Based on the framework of continuum damage mechanics, the anisotropic damage of muscle tissue is expressed by a second-order damage tensor. The evolution of the damage is assumed to depend on the current strain and damage. The evolution equation is formulated using the representation theorem of tensor functions. The proposed model is applied to the experimental data on tensile mechanical properties in the fiber direction and the compression properties in the fiber and cross-fiber directions in literature. The model can predict non-linear mechanical properties and breaking points. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jmbbm.2009.05.001

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

This study aimed to develop a three-dimensional constitutive model of skeletal muscle that describes anisotropy of deformation, viscoelasticity, and damage evolution. Muscle tissue has a transverse isotropic structure. We describe anisotropy of the mechanical properties of muscle using a structural tensor. Free energy function of muscle is defined and decoupled into the volumetric, isochoric elastic and isochoric viscoelastic contribution. The viscoelastic part is modeled as a three-dimensional viscoelastic model that is constructed by extending one-dimensional rheological model. Based on the framework of continuum damage mechanics, the anisotropic damage of muscle tissue is described by a damage tensor of second rank. To represent the effects on muscle activity, we incorporate a contractile element into the model. The active stress is defined as a first Piola-Kirchhoff stress tensor considering the mechanism of muscle force generation.

DOI： 10.1299/jsmemecjo.2007.5.0_175

CiNii Books

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：山梨大学  

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記述言語：英語   会議種別：口頭発表（一般）  

開催地：西安市  

血管構造を有する肝臓有限要素モデルの開発とそれを組み込んだ人体モデルの衝突解析への適用

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：パシフィコ横浜  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：パシフィコ横浜  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：パシフィコ横浜  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：京都大学  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：京都大学  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：京都大学  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：埼玉大学  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：ピアザ淡海  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：ピアザ淡海  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：パシフィコ横浜  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：静岡大学  

Lumbar spinal stenosis is a common medical problem in elderly individuals and may lead to disabling neurogenic claudication. This study aimed to figure out the changes of kinematics and biomechanical effect on lumbar spine finite element (FE) model after pedicle-lengthening osteotomy by comparing them to the intact healthy male FE lumbar spine model.A three-dimensional FE model of intact lumbar spine was constructed and the pedicle-lengthening osteotomy surgery was performed at L4 by using pedicle-lengthening screw.The maximum change in stress of the intervertebral discs was -23.0% at L3 in flexion, -17.7% at L4 in extension, 6.5% at L5 in left bending, 13.5% at L5 in right bending, 13.4% at L4 in left rotation and 28.4% at L4 in right rotation.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：ウインクあいち  

衝撃試験 プロテクタ装着により衝撃持続時間と変位量が増加し，骨頭荷重が 減少する 転倒時，地面に対する頸部軸角度の違いが荷重値に影響を及ぼす

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：ウインクあいち  

自動車乗員保護のために，プリクラッシュセーフティ技術の開発が進められ，衝突前のブレーキによる乗員の姿勢変化が衝突後の乗員挙動に与える影響が注目されている．しかし，従来の検討では，あるひとつの乗員モデルについてプリクラッシュセーフティシステムの効果を確認するものが多く，乗員の体格差を考慮したものは少なかった．本研究では，小柄体型女性モデルを用いて，衝突前のブレーキを考慮した2種類の前面衝突を再現し，男性乗員モデルとの比較を行うことで，乗員の体格差が衝突後の挙動に与える影響を調査した．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：ウインクあいち  

死亡率に基づく歩行者保護技術の効果評価方法の有用性を示した．本論文では車両剛性に限定し解析をおこなったが，本評価手法の妥当性検証と併せて，より実際に近い歩行者保護デバイスの評価の評価も今後おこなっていく．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：ウインクあいち  

本研究では，門脈およびその内部の血液を再現した肝臓モデルを構築し，人体FEモデルを用いた側面衝突の有限要素解析を行い，運転席乗員の血流に起因した肝臓損傷について検討した．以下に結論を示す． 1. 腹部および胸部が客室と接触することで，肋骨および肋軟骨を通して肝臓が変形する．2. アームレストと腹部の接触により，肝臓下部が大きく変形する．3. 肝臓が圧縮されることにより，門脈入口付近に応力集中が発生する．4. 衝突解析において，肝臓内部の損傷を正しく評価するには血流を再現したシミュレーションが有効である．

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記述言語：英語   会議種別：口頭発表（一般）  

開催地：The First World Hotel, Hangzhou, China  

The effects of the change in posture due to pre-impact braking on the kinematic behavior were investigatedby using FE analysis and a human FE model. The full-width frontal impact and small-overlapfrontal impact were selected as the crash pulse. Spinal flexion and rotation angles were evaluated by using theEuler angle. The neck extension, which was observed in dummy tests, was relatively small in the human FEmodel simulation because of the upper body twisting behavior caused by the human spine flexibility.

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記述言語：英語   会議種別：口頭発表（一般）  

開催地：The First World Hotel, Hangzhou, China  

The method of calculating the head trajectory in three dimensions within the passenger compartment using the head and vehicle's acceleration and angular velocity in their respective local coordinate systems was constructed. To verify this calculation method, a crash simulation in LS-DYNA was conducted to compare the calculated and simulated result. Next, in order to demonstrate real-world usability of this method, the dummy's head trajectory was calculated using the linear acceleration and angular velocity of the dummy's head obtained from a sled test. The calculated result was then compared to the trajectory obtained from video analysis of the crash test. The possibility of obtaining the head trajectory in the global coordinate system from the local head's acceleration and angular velocity using LS-DYNA and MADYMO was also investigated. The head trajectory of a vehicle occupant with respect to the vehicle coordinate system and global coordinate system can be obtained using these methods.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：札幌コンベンションセンター  

Chest injury of the occupant is usually severe upon experiencing high deceleration during a vehicle frontal crash, hence reduction of this chest injury is important for occupant protection. A finite element sled model was created to investigate the different methods to protect the occupant's chest during the high deceleration in a crash. The simulation obtained was compared to experiments to ensure consistency. The causes for chest deflection on the Hybrid III AM50 dummy was then investigated, followed by methods to reduce this injury.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：札幌コンベンションセンター  

This paper describes the effects of using a current AEB system in real world accident scenarios, and identifies when AEB will increase the injury risk of a pedestrian in a collision even though impact speed was lower. The use of AEB in vehicles may cause vehicle and pedestrian kinematics to change from the original accidents, and in turn the pedestrian impact location on the car may change as well. As such, the pedestrian has a possibility of hitting a stiffer part of the vehicle, suffering a more serious injury. The injury parameters used in this paper to assess pedestrian injury are both impact speed and HIC.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：名古屋大学東山キャンパス  

本研究においては車体の変形量を計測することによって，車体の変形エネルギを求め，車両の衝突速度を導出することを目的に行った．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：名古屋大学東山キャンパス  

本研究では，血流を再現した肝臓モデルを構築し，肝臓モデル単体および人体FEモデルを用いた有限要素解析を行い，血流に起因した肝臓損傷について検討した．結論を以下に示す．1. 肝臓モデル単体の動的圧縮解析において，血流に起因して門脈入口付近で応力集中が発生する．2. 圧縮率に対する荷重応答は実質のみのモデルでも再現できる．3. 人体内において，肝臓内部の損傷を正しく評価するには，血流を再現したシミュレーションが有効である．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：パシフィコ横浜  

The method of calculating the head trajectory in three dimensions within the passenger compartment using the head and vehicle's acceleration and angular velocity in their respective local coordinate systems was constructed. To verify this calculation method, a crash simulation in LS-DYNA was conducted to compare the calculated result and the simulated result. The possibility of obtaining the head trajectory in the global coordinate system from the head and vehicle's acceleration and angular velocity in their respective local coordinate systems using LS-DYNA and MADYMO was also investigated. The head trajectory of a vehicle occupant with respect to the vehicle as well as the global coordinate system can be obtained using these methods.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：パシフィコ横浜  

愛知県の交通事故カルテに用いて自動車対歩行者および自動車対自転車の死亡事故について分析した．道路状況や法令違反の有無・種類によって事故を分類した．それにより道路の幅員の大きさが歩行者の事故に，交差点の見通しが自転車の事故に大きな影響を及ぼすことを明らかにした．

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記述言語：英語   会議種別：口頭発表（一般）  

開催地：Hongik University, Seoul, South Korea  

In a vehicle-cyclist collision, cyclist kinematics are comparable with that of a pedestrian, except that the cyclist exhibits a pelvis slide behavior on the hood top [1]. A cyclist will assume various cyclic postures of the lower extremities while pushing on the pedals in a rotary motion when pedaling. It is not clear whether these lower extremity postures and velocities of the cyclist affect kinematics and injuries. In this study, the influence of lower extremity posture on cyclist kinematics and injuries was investigated with and without bicycle velocity.

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記述言語：英語   会議種別：口頭発表（一般）  

開催地：Hongik University, Seoul, South Korea  

In this study, head impact conditions in judo were reproduced with a human FE model, and brain kinematics and injuries were examined in order to understand head injury mechanisms in judo. A head FE model reflecting anatomical and mechanical characteristics was used. Experimental data of translational and rotational acceleration were input to the FE model. The brain strain distribution and some injury measures were investigated.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：愛知工業大学  

有人宇宙飛行の緊急脱出を想定して，Hybrid III と人体FEモデルに鉛直上向き荷重，後面衝撃荷重を与えた．結果は以下の通りである．(1)Hybrid III は鉛直上向きの荷重入力に対して，体幹が変形せず，腰部，胸部，頭部が同じ加速度を示し，人体応答を検討するモデルとしては適していない．(2)人体有限要素モデルでは，胸部，腰部に続いて頭部が加速される．全身挙動は初期姿勢に依存する部分が大きく，アップライトの姿勢ではそのままの姿勢を保ちつつ，全身が上方に加速される．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京工業大学  

Occupant's chest injury is especially severe in the high deceleration vehicle frontal crash, therefore reduction of occupant's chest injury is needed for the occupant protection. In this research, a sled test under high deceleration crash pulse was reproduced to investigate the protection methods of occupant's chest under the high deceleration pulse. We validated the sled model by comparing with experimental result and examined the mechanism of chest deflection of Hybrid III dummy. It was showed that forward displacement of dummy's pelvis in high-deceleration sled model was larger than that in the small car model. This large forward displacement of pelvis caused larger inner shoulder belt force. It is needed to lower pelvis displacement to reduce dummy chest deflection.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：北九州国際会議場  

A cyclist takes different postures of lower extremities while pushing the pedals. In this research, the kinematics of the whole body and injury risk of cyclist were examined for three representative postures of the lower extremities with and without cyclist traveling velocity. The knee height of the cyclist relative to the hood leading edge affected the kinematics and the head impact location against the car. The bicycle velocity influenced not only head impact location in the car lateral direction but also knee deformation.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：パシフィコ横浜  

The objective of this study is to understand the effects of car rotation on occupant kinematic behavior in vehicle impact with rotation. The method to provide the boundary condition for the occupants under car acceleration and rotation was formulated. Small overlap frontal crash (yawing), full-width crash (pitching) and offset impact tests (yawing and pitching) were examined by FE model simulations. The vehicle yaw motions had a small effect on the occupant kinematics. The vehicle pitch motions mitigated the loading on occupants in a frontal crash since the anchor of the seatbelt moved with vehicle pitch rotation, which increased ridedown of the occupant.

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：朱鷺メッセ新潟コンベンションセンター  

本研究では，頭部インパクタ及び人体頭部モデルを用いてヘルメット有無別に路面への落下，自動車との衝突について有限要素解析を行い，ヘルメットの頭部保護性能を検討した．1.頭部インパクタによる解析において，ソフトシェルヘルメットの衝撃保護効果は大きかったが，人体モデルを用いた解析では，Aピラー衝突時においてソフトシェルヘルメット装着時に，頭頂部で骨折が生じた．2.Aピラーの単純な変形を仮定した加速度波形モデルを用いた結果から，HICに対して衝突速度が低い場合はライナーとAピラーの変形特性の両者が影響するが，衝突速度が高い場合はAピラーの変形荷重の大きさの影響が大きい．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：朱鷺メッセ新潟コンベンションセンター  

本研究では，衝突ダミーHybrid IIIモデルと人体有限要素モデルを用いた衝突有限要素解析を行い，胸胸部加速度と胸たわみの発生要因およびフォースリミッタ荷重とシートベルトパス条件を変更した際の影響について検討した．1.乗員の胸部加速度と胸たわみには相関関係があるが，胸部加速度にはダミー内力が影響する．2.Hybrid IIIダミーでは，フォースリミッタ荷重やシートベルトパスなどの拘束条件の違いが胸たわみに大きな影響を及ぼすが，胸部加速度に対する影響は小さい．3.ベルトパスやフォースリミッタ荷重などの拘束条件を検討する上では，Hybrid IIIに加え人体モデルでの確認が必要である．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：朱鷺メッセ新潟コンベンションセンター  

本研究では，足関節の傷害発生時の現象をより詳細に解析するために，足関節モデルの構築を行った．骨，筋肉，靭帯について形状データを基に有限要素モデルを構築した．その後，打撃シミュレーションを行い，実験データと比較したところ，概ね妥当性のあるモデルであるという結果が得られた．課題としては，特に足関節への負荷がピークに達した後の除荷段階において再現性の向上が挙げられる．今後，このモデルを用いて，歩行者事故や前面衝突事故のシミュレーションを行い，足関節傷害の発生をより詳細に解析し，歩行者保護や乗員保護の研究に適用する．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：大同工業大学  

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東北大学片平キャンパス  

本研究では，頭部インパクタ及び人体頭部モデルを用いてヘルメット有無別に路面への落下，自動車との衝突について有限要素解析を行い，ヘルメットの頭部保護性能を検討した．1.頭部インパクタによる解析において，落下ではヘルメットによる大きな加速度低減効果がみられたが，Aピラー衝突においてはその効果は小さかった．また，加速度波形に対して，頭部とヘルメットの間隙およびヘルメットの慣性力が影響を及ぼすことがわかった．2.人体モデルを用いた解析において，落下およびAピラー衝突解析ともに，ヘルメットによる頭蓋骨骨折の防止効果が大きいことがわかった．ただし，Aピラーの衝突時には，ヘルメット装着時であっても脳のひずみが大きくなり，脳損傷が発生する可能性が大きいと考えられる．

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記述言語：日本語   会議種別：口頭発表（一般）  

開催地：名古屋国際会議場  

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記述言語：英語   会議種別：口頭発表（一般）  

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記述言語：英語   会議種別：口頭発表（一般）  

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記述言語：英語   会議種別：口頭発表（一般）  

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記述言語：英語   会議種別：口頭発表（一般）  

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記述言語：英語   会議種別：口頭発表（一般）  

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