• 한국소음진동공학회논문집
• /
• 제22권6호
• /
• pp.502-508
• /
• 2012

An analytical model for a human body is important to predict muscle and joint forces. Because it is difficult to estimate muscle or joint forces from a human body, the objective of this study is the development of a reliable analytical model for a human body to evaluate the lower extremity muscle and joint forces. The musculoskeletal system of the human lower extremity is modeled as a multibody system employing the Hill-type muscle model. Muscle forces are determined to minimize energy consumption, and we assume that motion is constrained in the sagittal plane. Muscle forces are calculated through an equilibrium analysis while rising from a seated position. The musculoskeletal model consists of four segments. Each segment is a rigid body and connected by frictionless revolute joints. Muscles of the lower extremity are simplified to seven muscles with those that are not related to the sagittal plane motion are ignored. Muscles that play a similar role are combined together. The results of the present study are compared with experimental results to validate the lower extremity model and the assumptions of the present study.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2013년도 춘계학술대회 논문집
• /
• pp.516-517
• /
• 2013

Whole body vibration is very important for operators in construction equipment (CE) industry. There is ISO 2631 regulation to protect operators of CE. Recently WBV is one of critical performance parameters of CE to give operators much better comfortable working environment. And there are many kinds of numerically simplified human body model for the motor industry. We applied one human body model in ISO 5982 for the CE development at early stage. And we've checked the validity of this model to consider WBV by the operator comfort point of view.

• 설비공학논문집
• /
• 제19권4호
• /
• pp.299-306
• /
• 2007

Recently, the numerical analysis using person shape model for CFD (Computational Fluid Dynamic) has been researched widely for the thermal comfort and inhaled air quality of human body in the indoor environments. The purpose of this research is to examine the characteristic of airflow and thermal environment around human body by the experiment of displacement ventilation that assumes the indoor environment of natural convection. In this study, thermal manikin was used instead of real human body. The Airflow characteristic around human body was measured in precision by PIV (Particle Image Velocimetry). This experimental result will be used as data for CFD benchmark test using person shape model.

• 한국산업보건학회지
• /
• 제7권1호
• /
• pp.87-98
• /
• 1997

In this study, subway train vibration has been measured to characterize the whole body vibration of Seoul subway lines for various human postures. Results show that the floor vibration level of the subway trains in the vertical direction is higher than that in other directions. At the standing human posture, vibration level of the head in the right-left direction are increased while that in the vertical direction is decreased. It is assumed that the different flexibility of the human body and the rolling motion of the subway trains are the main cause. At the sitting posture with back seat on, vibration level in the right and left direction at the human ischial tuberosities is lower than that in other directions. Results also show that there were little difference between back-seat on model and back-seat off model. Transmissibility analysis shows how the subway vibration affects the response of a human body.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2000년도 추계학술대회논문집A
• /
• pp.522-528
• /
• 2000

Dynamic characteristics of seated human body were investigated by measuring apparent masses of eight different seating subjects exposed to vertical vibration. Two types of vibration signals - one is random signals over 1 to 30Hz having flat spectral density and the other is signals measured on seat rail in passenger car under driving conditions - were employed. It was found that the apparent masses are highly dependent on vibration level rather than type of the vibration signals. Based on the apparent mass measurements, a mathematical model of the human body in seating posture was developed by using genetic algorithm. Three-degree-of-freedom model was satisfactory in describing apparent mass of seated human body.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 추계학술대회
• /
• pp.459-464
• /
• 2004

The rifle impact of human body affected by the posture of human for rifling. The interaction human-rifle system influence the firing accuracy. In this paper, impact analysis of human model for shooting posture is carried out. ADAMS code and LifeMOD is used in impact analysis of human model and modeling of the human body, respectively. On the shooting, human model is affected by rifle impact during the 0.001 second. Performed simulation time for shooting is 0.1 second. Applied constraint condition to human-rifle system is rotating and spherical condition. As the results, the displacement of rifle and transfer path analysis of impact of human model is presented.

• 한국전자파학회논문지
• /
• 제19권7호
• /
• pp.727-732
• /
• 2008

최근 몇 년간 전자파 관련 장비 사용이 증가함에 따라 전자파의 인체 영향 또한 관심이 증가하고 있으며, 또한 이러한 영향을 구체적으로 파악하기 위한 연구가 진행 중이다. 이에 대한 일환으로 이동 통신 단말기에 의한 전자파 인체 흡수율(SAR)에 의한 국내외 표준 제정에 관한 연구가 활발히 진행되었다. 그러나 인체에 대한 침투력이 상대적으로 큰 단파 대역(HF: High Frequency)에 의한 인체 유도 전류에 대한 표준은 연구가 미흡한 편이다. 특히 교통 카드와 도서관 등에서 사용되는 RFID 장비의 활발한 도입으로 RFID 장비의 방출 전자파에 의한 인체 영향 연구가 절실하다. 본 논문은 단파 대역인 13.56 MHz에서 동작하는 RFID 장비에 의하여 인체에 유도되는 전류와 유사한 유도 전류값을 갖는 실린더형 인체 등가 안테나 모형을 설계 및 제작함으로써 RFID 장비의 방출 전자파에 의한 인체의 영향을 양적으로 파악하고, 인체와 인체 등가 모형에 유기되는 유도 전류의 유사성을 확인하였다.

• ETRI Journal
• /
• 제33권4호
• /
• pp.569-579
• /
• 2011

This paper presents a novel approach for human activity recognition (HAR) using the joint angles from a 3D model of a human body. Unlike conventional approaches in which the joint angles are computed from inverse kinematic analysis of the optical marker positions captured with multiple cameras, our approach utilizes the body joint angles estimated directly from time-series activity images acquired with a single stereo camera by co-registering a 3D body model to the stereo information. The estimated joint-angle features are then mapped into codewords to generate discrete symbols for a hidden Markov model (HMM) of each activity. With these symbols, each activity is trained through the HMM, and later, all the trained HMMs are used for activity recognition. The performance of our joint-angle-based HAR has been compared to that of a conventional binary and depth silhouette-based HAR, producing significantly better results in the recognition rate, especially for the activities that are not discernible with the conventional approaches.

• 대한인간공학회지
• /
• 제14권2호
• /
• pp.33-39
• /
• 1995

The inverse Kinematics can be used for representing the motion of human body model. In order to find the final figure of the human body model with given target position, we can uwe the formula x=J .THETA. , where J is the Jacobian matrix of x=f( .THETA.), of the Inverse Kinematics. In this formula, f has so complicated form that it is difficult to calcuate the Jacobian matrix J by expanding all formulae exactly. In this paper, a numerical method that calculates the Jacobian matrix is proosed. The simulation results obtained by using the simple human model reprsent that the proposed. The simulation results obtained by using the simple human model represent that the proposed method is useful for generating the final figure of the body model.

• Journal of electromagnetic engineering and science
• /
• 제11권1호
• /
• pp.51-55
• /
• 2011

Electromagnetic fields, radiated from an intestine-ingested source and propagated through an inhomogeneous human body model, are computed with the finite-difference time-domain (FDTD) method. The calculated results obtained at some receiving points vertically placed according to the abdomen of the human body model show unusual dip patterns in the frequency domain. The frequency of this unusual dip varies according to the location of the receiving points. Thus, the relationship between the frequency of the unusual dip and the incident angle of the line-of-sight is analyzed. The effect of the location of an ingested source on the above relationship is also investigated. The slope of the approximately linear relationship is affected by the location of the ingested source.