• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.6
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• pp.642-653
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• 2008

This study deals with modeling of head-related transfer functions(HRTFs) using principal components analysis(PCA) in the time and frequency domains. Four PCA models based on head-related impulse responses(HRIRs), complex-valued HRTFs, augmented HRTFs, and log-magnitudes of HRTFs are investigated. The objective of this study is to compare modeling performances of the PCA models in the least-squares sense and to show the theoretical relationship between the PCA models. In terms of the number of principal components needed for modeling, the PCA model based on HRIR or augmented HRTFs showed more efficient modeling performance than the PCA model based on complex-valued HRTFs. The PCA model based on HRIRs in the time domain and that based on augmented HRTFs in the frequency domain are shown to be theoretically equivalent. Modeling performance of the PCA model based on log-magnitudes of HRTFs cannot be compared with that of other PCA models because the PCA model deals with log-scaled magnitude components only, whereas the other PCA models consider both magnitude and phase components in linear scale.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.4
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• pp.8-13
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• 2008

Since hundreds thousands of pedestrians are killed or injured in car accidents every year, a variety of research efforts have been performed to protect pedestrians in pedestrian-vehicle crashes. The IHRA reports that injuries on the child head, the adult head, and the adult lower leg/knee are the most critical in the crashes. Identifying the current status of international activities on pedestrian protection, this study, in particular, carries out headform impact test using selected domestic vehicles categorized by three groups - Sedan, SUV (Sport Utility Vehicle), and 1 Box (One Box) Vehicle. According to the valuable findings from the test results, this paper proposes a methodology under which the Korean Technical Regulation for protecting pedestrians in pedestrian-vehicle crashes will be developed.

• The Research Journal of the Costume Culture
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• v.12 no.6 s.53
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• pp.1021-1030
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• 2004

The purpose of this study was to develop and make the head form by setting the region of the head for detailed measurement of the head to make the type of closely fit hat and typifying the head form of Korean women's with each region of the head based on the measurements of each region of the head according characteristics. A total of 285 Korean women's in the age group of 18 to 35 years old. It were measured through the direct measurement method by selecting 67 measurement items. As a result of the findings obtained from cluster analysis could be classified into 3 type. Type 1($46\%$) is U-shaped form, that is high in head height on sides and circumference is smallest, whose facial region and occiput is flattest of three types. Type 2($22.4\%$) is inverted triangle form, that is flat in head ridge, low in head height on sides and wide in the frontal width. Type 3($31.6\%$) is oval form, that is largest in size, has the projected occiput and is of three-dimensional form.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.4 s.152
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• pp.542-553
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• 2006

The purpose of this study were to analyse of craniofacial shape by 3D and to develope of head models for Korean adults with gender and age groups. The 3D measurement technique adapted in this study was a novel approach compared that the same technique has been commonly used in measuring human bodies. The data and the model of head analysis can be used as a basic reference in developing various head related items such as hat, helmet, gas mask, ear phone, and etc. In this study, heads of 836 Korean adults were measured in 3D, analyzed by statistical methods, and modelized in 3D by gender and age groups. From the basic statistical data analysis, vertex-tragion and the length between the pupils were the longest in their twenties for both men and women, and grew shorter in elderly groups. In all categories, a significant difference appeared between men and women in their 20's, but the differences were less noticeable in elderly groups. Compared to the one size standard head model of the Korea Occupational Safety and Health Agency, the above three-dimensional standard head model would provide a more through fit because gender and age groups were sub-divided and analyzed in 3D.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.3
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• pp.374-379
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• 2017

In vehicle to pedestrian accidents, cracks occur in the vehicle laminated glass due to impact of a pedestrian's head. In this study, FMH(Free Motion Headform) was used to experiment on and analyze the crack patterns on a vehicle laminated glass that collides with an adult headform at speeds of 20 km/h, 30 km/h, and 40 km/h, respectively. Applying the acquired experimental data and material property of the vehicle laminated glass to the structural analysis program LS-Dyna, we could develop the FE model of vehicle laminated glass similar to real vehicle laminated glass. We could estimate the head impact velocity and pedestrian's vehicle impact velocity using the Madymo program.

• Journal of Biosystems Engineering
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• v.9 no.1
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• pp.1-4
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• 1984

노외차량(路外車輛)의 승차(乘車) 시뮬레이션을 위한 착석(着席) 상태(狀態)의 운전자(運轉者) 모델을 개발(開發)하였다. 운전자(運轉者) 모델은 머리, 몸체, 신부(腎部)로 크게 나누어 자유도(自由度) 3의 진동체로 가정(假定)하고 머리와 몸체, 몸체와 신부(腎部)는 각각 목과 장기(臟器)를 나타내는 탄성체로서 연결하였다. 또한 인체의 해부학적(解部學的) 구조(構造)와 일치(一致)하도록 머리와 신부(腎部)사이에는 척추(脊椎) 부분(部分)을 포함시켰다. 모델의 각 변수(變數)들은 기존(旣存)의 실험(實驗) 결과(結果)를 이용(利用)하여 머리부의 진동(振動)이 실험(實驗) 결과(結果)와 일치(一致)하도록 시뮬레이션 방법(方法)으로 결정(決定)하였다.

• Journal of Korean Society of Transportation
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• v.20 no.3
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• pp.105-113
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• 2002

As the number of pedestrian accident increases, the reconstruction of an accident becomes important to find the source of the fault. Generally, accidents are reconstructed by the intuition of experts or primitive physics. A reconstruction method is proposed using sophisticated optimization technology. At first, a dynamic simulation model is established for the accident environment. Occupant analysis for automobile crashworthiness is employed. The situation before an accident is identified by optimization. The impact velocity and the position of the pedestrian are utilized as design variables. The design variables are found by minimizing the difference between the simulation and the real accident. The optimization process is performed by linking an occupant analysis program MADYMO to an optimization program VisualDOC. Since the involved analysis is dynamics and highly nonlinear, response surface method is selected for the optimization process. Problems are solved for various situations.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.116-119
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• 2006

본 논문에서는 자동차후면추돌이나 에어백시험 등에서 인체모형의 중요한 평가지수인 목 상해를 평가 할 수 있는 평가시스템에 대하여 연구하였다. 목 상해($N_{ij}$) 기준만족여부를 판단하기 위하여 Diadem 프로그램을 이용하여 더미(Dummy)의 종류별, 시험의 조건별로 자동으로 계산되는 평가시스템을 개발하여 목 상해 기준을 보다 편리하고 정확하게 계산 할 수 있도록 하였다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.920-927
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• 2008

This study deals with modeling of Head-Related Transfer Functions (HRTFs) using Principal Components Analysis (PCA) in the time and frequency domains. Four PCA models based on Head-Related Impulse Responses (HRIRs), complex-valued HRTFs, augmented HRTFs, and log-magnitudes of HRTFs are investigated. The objective of this study is to compare modeling performances of the PCA models in the least-squares sense and to show the theoretical relationship between the PCA models. In terms of the number of principal components needed for modeling, the PCA model based on HRIR or augmented HRTFs showed more efficient modeling performance than the PCA model based on complex-valued HRTFs. The PCA model based on HRIRs in the time domain and that based on augmented HRTFs in the frequency domain are shown to be theoretically equivalent. Modeling performance of the PCA model based on log-magnitudes of HRTFs cannot be compared with that of other PCA models because the PCA model deals with log-scaled magnitude components only, whereas the other PCA models consider both magnitude and phase components in linear scale.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.11a
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• pp.103-106
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• 2009

요즘 사람들이 인체에 대하여 많은 관심을 가지고 있다. 그러면서 나의 몸에 작은 변화가 일어 났을 때 나의 신체는 어떻게 변할 것인가에 대한 궁금증이 생기게 되었다. 인체의 변화는 많은 사람들 마다 조금씩 차이는 있겠지만 비슷한 변화를 있을 것이라고 추측 하였다. 일반 사람들에게 정보를 제공하기 위해서는 서비스하는 데이터가 통계적 검증 절차를 받아야 하는 관계로 일반적으로 많은 실험을 통해 얻어진 데이터들을 보여주도록 하였다. 본 시스템 에서는 인체모형 중 남자 머리 구조를 시각화 하여 심리/생리, 음향/음성 에 따른 머리의 변화되는 모습을 보여주도록 하였다. 또 머리를 구조화 하여 시뮬레이션 할 수 있는 공간을 제공하여 방문한 사람들이 이용하기 쉽고 뚜렷한 데이터를 서비스 하였다. 그리하여 전문가, 학생 또는 일반 사람들이 인체 변화에 대한 궁금한 점을 최대한 해결 할 수 있도록 해준다.