• 대한인간공학회지
• /
• 제19권1호
• /
• pp.77-90
• /
• 2000

The aim of this study is to develop and evaluate an efficient camera calibration method for vision-based head tracking. Tracking head movements is important in the design of an eye-controlled human/computer interface. A vision-based head tracking system was proposed to allow the user's head movements in the design of the eye-controlled human/computer interface. We proposed an efficient camera calibration method to track the 3D position and orientation of the user's head accurately. We also evaluated the performance of the proposed method. The experimental error analysis results showed that the proposed method can provide more accurate and stable pose (i.e. position and orientation) of the camera than the conventional direct linear transformation method which has been used in camera calibration. The results of this study can be applied to the tracking head movements related to the eye-controlled human/computer interface and the virtual reality technology.

• International Journal of Safety
• /
• 제6권1호
• /
• pp.1-6
• /
• 2007

Operation of human-centered robot, in general, facilitates the creation of new process that may potentially harm the human operators. Design of safety-guaranteed operation of human-centered robots is, therefore, important since it determines the ultimate outcomes of operations involving safety of human operators. This study discusses the application of geometric tolerance and head injury criteria to safety assessment of human-centered robotic operations. Examples show that extending "Work Area" has more significant effect on the uncertainty in safety than extending the system range in the presence of velocity control.

• Journal of Mechanical Science and Technology
• /
• 제15권7호
• /
• pp.995-1001
• /
• 2001

The finite element human head model is developed for traumatic injury assessment. The model is constructed based on the precise anatomical geometry and validated with test results. In this paper, structural and physiologic explanation of human head will be introduced as well as the modeling methodology. Some of simulation results are also chosen to present major features of the model.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제16권2호
• /
• pp.131-139
• /
• 2016

Recognition of human motions has become a main area of computer vision due to its potential human-computer interface (HCI) and surveillance. Among those existing recognition techniques for human motions, head detection and tracking is basis for all human motion recognitions. Various approaches have been tried to detect and trace the position of human head in two-dimensional (2D) images precisely. However, it is still a challenging problem because the human appearance is too changeable by pose, and images are affected by illumination change. To enhance the performance of head detection and tracking, the real-time three-dimensional (3D) data acquisition sensors such as time-of-flight and Kinect depth sensor are recently used. In this paper, we propose an effective feature extraction method, called adaptive local binary pattern (ALBP), for depth image based applications. Contrasting to well-known conventional local binary pattern (LBP), the proposed ALBP cannot only extract shape information without texture in depth images, but also is invariant distance change in range images. We apply the proposed ALBP for head detection and tracking in depth images to show its effectiveness and its usefulness.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 1998년도 하계종합학술대회논문집
• /
• pp.749-752
• /
• 1998

Recognizing a human part becomes very important for applications which are based on the interaction between computers and their users. In this paper, we design and implement a system which recognizes and tracks a human head using a sequence of images. Difference images are used to easily extract feature vectors from images with very complex backgrounds. A human bhead is represented with an ellipse and recognized by searching for a maximum value from preprocessed gradient images. The method is developed by considering the fact that the tracking system should be real-time. The designed system not only shows an excellent performance for the normal up-right position of the head, but also for the cases of 360.deg. rotated head position, occluded images of heads, and tilted head positions.

• 로봇학회논문지
• /
• 제5권3호
• /
• pp.262-269
• /
• 2010

This paper presents a probabilistic head tracking method, mainly applicable to face recognition and human robot interaction, which can robustly track human head against various variations such as pose/scale change, illumination change, and background clutters. Compared to conventional particle filter based approaches, the proposed method can effectively track a human head by regularizing the sample space and sequentially weighting multiple visual cues, in the prediction and observation stages, respectively. Experimental results show the robustness of the proposed method, and it is worthy to be mentioned that some proposed probabilistic framework could be easily applied to other object tracking problems.

• 제어로봇시스템학회논문지
• /
• 제7권4호
• /
• pp.309-318
• /
• 2001

In this paper, we describe methods that analyze a human gesture. A human interface(HI) system for analyzing gesture extracts the head and hand regions after taking image sequence of and operators continuous behavior using CCD cameras. As gestures are accomplished with operators head and hands motion, we extract the head and hand regions to analyze gestures and calculate geometrical information of extracted skin regions. The analysis of head motion is possible by obtaining the face direction. We assume that head is ellipsoid with 3D coordinates to locate the face features likes eyes, nose and mouth on its surface. If was know the center of feature points, the angle of the center in the ellipsoid is the direction of the face. The hand region obtained from preprocessing is able to include hands as well as arms. For extracting only the hand region from preprocessing, we should find the wrist line to divide the hand and arm regions. After distinguishing the hand region by the wrist line, we model the hand region as an ellipse for the analysis of hand data. Also, the finger part is represented as a long and narrow shape. We extract hand information such as size, position, and shape.

• International Journal of Human Ecology
• /
• 제7권1호
• /
• pp.77-83
• /
• 2006

The ability to customize garments for fit in the apparel industry is directly tied to the availability of comprehensive and accurate sets of anthropometrical data for each consumer. The data for apparel sizing systems is available from three major standard/ research organizations: ASTM (American Society for Testing and Materials), ISO (International Standard Organization), and NCHS (National Center for Health Statistics). However, these standards ignore various head shapes and are outdated for the development future head products. This creates a data gap an ever changing multi-cultural society such as the United Sates. Although major government and industry safety organizations recognize the importance of safety for head products, few studies were found to support their reasoning. The purpose of this study is to provide accurate head dimension data for developing safety head products by analyzing various head shapes in the United Sates which includes various ethnic backgrounds. This study was carried out on 105 males in the United States. Factor analysis, cluster analysis, Moreover, Duncan analysis were all used for analyzing various head shapes.

• 한국방사선학회논문지
• /
• 제11권3호
• /
• pp.139-146
• /
• 2017

Brain MRI 검사에서는 영상을 얻기 위해 RF Pulse를 인체에 조사하게 되는데 이때 조사된 RF Pulse 에너지의 상당부분은 우리 몸에 그대로 흡수되게 되고 이로 인해 인체의 온도가 상승하게 되는데 노출 정도에 따라 인체에 영향을 주게 된다. 동일한 RF Pulse 에너지를 주었더라도 인체에 금속이 삽입되었다면 금속으로 인해 인체의 전도도가 상당히 증가하기 때문에 SAR값이 증가하고 체온도 역시 상승할 것이다. 따라서 치아임플란트를 했을 때와 하지 않았을 때 인체의 머리에 나타나는 SAR값의 변화와 인체의 온도변화는 차이가 있지 않을까라는 의문으로 이번 연구를 시작하게 되었다. 실험은 3.0 Tesla MRI장비에서 발생되는 128MHz RF Pulse 주파수대에서 치아임플란트의 사용 유무에 따른 인체가 받는 SAR와 체온의 변화를 XFDTD 프로그램을 사용하여 인체두부 모델과 치아임플란트 모델을 활성화시켜 실험하였다. MRI장비에서 치아임플란트로 인해 인체두부 모델에 흡수되는 SAR의 평균값과 체온 상승을 살펴 본 결과 모두 증가하고 있음을 알 수 있다. 또한 계산 결과 평균 최대 SAR값과 뇌 부분의 최대 온도 상승이 국제 안전 기준치 이하로 나타났으나, 치아임플란트의 개수 증가에 따라 값이 변할 수 있으므로 그 영향을 간과할 수 없으며, 향후 과제로 치아임플란트 개수와 체적의 증가와 치아임플란트 재질에 따른 SAR, 온도 상승 시뮬레이션이 필요하다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권4호
• /
• pp.1581-1585
• /
• 2015

Human papillomaviruses (HPVs) remain a serious world health problem due to their association with cervical and head and neck cancers. While over 100 HPV types have been identified, only a few subtypes are associated with malignancies. HPV 16 and 18 are the most prevalent oncogenic types in head and neck cancers. Although it has been proven that some subsets of benign and malignant head and neck lesions are associated with HPV, the general population have very little awareness and knowledge of their association with HPV. Therefore, the purpose of this study was to determine the knowledge of HPV and its links with head and neck benign and malignant lesions in a group of Pakistani dental patients who attended the Dental Department of the Sandeman provincial hospital in Quetta, Pakistan. One hundred and ninety-two patients were recruited and requested to answer a questionnaire. It was revealed that there was a low level of knowledge about HPV and its association with head and neck benign and malignant lesions among the participants. This result suggested that more education regarding the relationship of HPV in inducing head and neck benign and malignant lesions is required in this group of patients.