• Title/Summary/Keyword: photo sensor

Search Result 344, Processing Time 0.027 seconds

The Effect of Badminton Shoe Forefoot Flexibility during the Under Clear Quick Lunge from a Jump Smashing (배드민턴화의 굴곡성(Flexibility) 차이가 점프 스매싱 후 언더클리어 동작시 하지에 미치는 영향)

  • Yi, Jae-Hoon;Sohn, Jee-Hoon;Ryue, Jae-Jin;Lee, Ki-Kwang;Lee, Jung-Ho
    • Korean Journal of Applied Biomechanics
    • /
    • v.22 no.1
    • /
    • pp.105-111
    • /
    • 2012
  • The purpose of this study was to investigate the effect that difference in forefoot of shoe flexibility during the quick lunge from a jump smashing on the lower limbs and the plantar pressure distribution. For this 10 elite badminton players with over 10 years experience and right handed participated. Two kinds of badminton shoes were selected and tested mechanical testing for the forefoot flexibility. Motion analysis, ground reaction forces and plantar pressure distribution were recorded. It was required to conduct lunge movement after jumping smashing as possible as high. Photo sensor was located in 3 meter away from standing position and its height was 40 cm. Subjects were conducted to return original position after touching the sensor as under clear movement as possible as fast. Forefoot stiffness had an effect on shoe peak bending degree and peak bending angular velocity in propulsion phase. Forefoot flexibility had an effect on ankle plantar flexion and knee flexion moment. It appears that joint power on lower limb and peak plantar pressure were not influenced by the flexibility of shoes.

Geometric Regualrization of Irregular Building Polygons: A Comparative Study

  • Sohn, Gun-Ho;Jwa, Yoon-Seok;Tao, Vincent;Cho, Woo-Sug
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.25 no.6_1
    • /
    • pp.545-555
    • /
    • 2007
  • 3D buildings are the most prominent feature comprising urban scene. A few of mega-cities in the globe are virtually reconstructed in photo-realistic 3D models, which becomes accessible by the public through the state-of-the-art online mapping services. A lot of research efforts have been made to develop automatic reconstruction technique of large-scale 3D building models from remotely sensed data. However, existing methods still produce irregular building polygons due to errors induced partly by uncalibrated sensor system, scene complexity and partly inappropriate sensor resolution to observed object scales. Thus, a geometric regularization technique is urgently required to rectify such irregular building polygons that are quickly captured from low sensory data. This paper aims to develop a new method for regularizing noise building outlines extracted from airborne LiDAR data, and to evaluate its performance in comparison with existing methods. These include Douglas-Peucker's polyline simplication, total least-squared adjustment, model hypothesis-verification, and rule-based rectification. Based on Minimum Description Length (MDL) principal, a new objective function, Geometric Minimum Description Length (GMDL), to regularize geometric noises is introduced to enhance the repetition of identical line directionality, regular angle transition and to minimize the number of vertices used. After generating hypothetical regularized models, a global optimum of the geometric regularity is achieved by verifying the entire solution space. A comparative evaluation of the proposed geometric regulator is conducted using both simulated and real building vectors with various levels of noise. The results show that the GMDL outperforms the selected existing algorithms at the most of noise levels.

Performance Analysis of Wireless Communication Interface System Module Combined LED Light Device (LED조명 디바이스를 접목한 무선통신 인터페이스 시스템 모듈 성능 분석)

  • Jang, Tae-Soo;Lee, Jun-Myung;Park, Keon-Jun;Kim, Yong-Kab
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.16 no.11
    • /
    • pp.2431-2436
    • /
    • 2012
  • This paper is implemented simple visible light communication system by combining the communications through LED lighting. It uses a variable PD sensor to the receiver and 1~12 the LED light-emitting device to the transmitter to realize LED visible light communication. Initial distance value of the developed transmission and receiver is more than 0~1.5m for LED visible light communication, the overall system transmission rate is organized with thousands kbps variability visible light media transmission system. It was measured the performance experiment during lens wearing or not wearing in order to increase the overall efficiency of the LED module, configures the LED and PD to existing PC module for the performance analysis of the implemented research, experiments the maximum communication distance of the transmitter/receiver according to LED count and the transmission rate, check about application methods and the possibility.

A Study on Angle Measurements Using an Optical Fiber (광섬유를 이용한 각도 측정 연구)

  • Kim, A-Hee;Kim, Ji-Sun;Oh, Han-Byeol;Kim, Jun-Sik;Goh, Bong-Jun;Lee, Eun-Suk;Jung, Hyon-Chel;Choi, Ju-Hyeon;Baek, Jin-Young;Jun, Jae-Hoon
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.4
    • /
    • pp.605-611
    • /
    • 2015
  • The measurement and analysis of angular change have been studied in many fields. This study developed an angle measurement technique with optical fiber and photodiode. The position and attached angle of photodiode were investigated to find the proper combination of parameter. The results showed that the increased measuring range was achieved when the position of detector was away from the center of rotation. Inverse mathematical model was used to obtain angular changes with an optical fiber. The applications of this study include in optical sensor, joint angle measurement, and sport science.

DGPS/IMU-based Photogrammetry in China

  • Yingcheng, Li;Xueyou, Li;Jicheng, Zhao;Xunping, Gong;Tang, Liang
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.1215-1220
    • /
    • 2003
  • People's Republic of China is one of the most rapidly developing countries in the world today. There is a great demand on highly actual and accurate spatial information of the whole country, especially of West China which becomes the focus of development of the Chinese government right now and in the next years, but where still not enough topographic maps are available. This raises great challenges to the surveying and mapping community in China. Facing the new challenges the Chinese Academy of Surveying and Mapping (CASM) started its pioneer work early 2002 to explore new techniques and technologies available today toward increasing the map productivity. With import of a CCNS/AEROcontrol system in November 2002 the first DGPS/IMU-based photogrammetric project in China was successfully accomplished jointly by CASM and the Germany-based companies IGI and Techedge. Two photogrammetric blocks of 1:4,000 and 1:20,000 photo scale, respectively, were flown in Anyang, China. Direct georeferencing and integrated sensor orientation were conducted. Results achieved were proven by using ground check points and compared with those of aerial triangulation. Orthophotos generated based on direct georeferencing shows the high efficiency and quality, and thus proved the promise of the new technology. Furthermore several DGPS/IMU-based photogammetric projects was accomplished one by one and a big project of more than 100,000 km2 in the Inner Mongolia will be started in August 2003. The paper presents experiences with DGPS/IMU-based photogrammetry in China. Results achieved in concrete projects are shown and evaluated. Politic and technical specialties in China are discussed. Conclusions outline the potential of DGPS/IMU-based photogrammetric production in China.

  • PDF

Conceptual Design of Crew Support System Based on Wireless Sensor Network and Power Line Communication for Cruise Ship (전력선통신(Power Line Communication) 기반 센서네트워크를 이용한 크루즈선 승무원 지원 시스템 개념연구)

  • Kang, Hee-Jin;Lee, Dong-Kon;Park, Beom-Jin;Paik, Bu-Geun;Cho, Seong-Rak
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.46 no.6
    • /
    • pp.631-640
    • /
    • 2009
  • The highest priority of the cruise trip is the safety and comfort of its passengers. Though the cruise lines take every appropriate measure to ensure that their Passengers are safe and experience enjoyable vacations it is hard to fulfill all passenger's personnel requirement with limited number of crews. Generally, each passenger is issued an identification card which contains their digital photo and personal identification information on a magnetic strip that he or she must present when entering or leaving the ship. This technology allows the ship to know which Passengers and crew members are on board and which are not. However, this system has some limitations of functions and usage. To support each passenger as his or her personal liking, additional number of crews or some kind of new system is needed. In this paper, the crew support system based on sensor network using wireless and wired communication technologies was studied. To design the system, PLC(Power Line Communication) system and ZigBee based passenger location recognition, classification system has studied experimentally. By using this system, crews can serve passengers more closely and personally with less effort.

Preparation of Flexible 3D Porous Polyaniline Film for High-Performance Electrochemical pH Sensor (고성능 전기 화학 pH 센서를 위한 유연한 3차원 다공성 폴리아닐린 필름 제조)

  • Park, Hong Jun;Park, Seung Hwa;Kim, Ho Jun;Lee, Kyoung G.;Choi, Bong Gill
    • Applied Chemistry for Engineering
    • /
    • v.31 no.5
    • /
    • pp.539-544
    • /
    • 2020
  • A three-dimensional (3D) porous polyaniline (PANI) film was fabricated by a combined photo-and soft-lithography technique based on a large-area nanopillar array, followed by a controlled chemical dilute polymerization. The as-obtained 3D PANI film consisted of hierarchically interconnected PANI nanofibers, resulting in a 3D hierarchical nanoweb film with a large surface and open porous structure. Using electrochemical measurements, the resulting 3D PANI film was demonstrated as a flexible pH sensor electrode, exhibiting a high sensitivity of 60.3 mV/pH, which is close to the ideal Nernstian behavior. In addition, the 3D PANI electrode showed a fast response time of 10 s, good repeatability, and good selectivity. When the 3D PANI electrode was measured under a mechanically bent state, the electrode exhibited a high sensitivity of 60.4 mV/pH, demonstrating flexible pH sensor performance.

Fabrication of the Imaging Lens for Mobile Camera using Embossing Method (엠보싱 공법에 의한 카메라 모듈용 광학렌즈 성형기법에 대한 연구)

  • Lee, C.H.;Jin, Y.S.;Noh, J.E.;Kim, S.H.;Jang, I.C.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2007.05a
    • /
    • pp.79-83
    • /
    • 2007
  • We have developed a compact and cost-effective camera module on the basis of wafer-scale replication technology. A multiple-layered structure of several aspheric lenses in a mobile camera module is first assembled by bonding multiple glass-wafers on which 2-dimensional replica arrays of identical aspheric lenses are UV-embossed, followed by dicing the stacked wafers and packaging them with image sensor chips. We have demonstrated a VGA camera module fabricated by the wafer-scale replication processing with various UV-curable polymers having refractive indices between 1.4 and 1.6, and with three different glass-wafers of which both surfaces are embossed as aspheric lenses having 200 um sag-height and aspheric-coefficients of lens polynomials up to tenth-order. We have found that precise compensation in material shrinkage of the polymer materials is one of the most technical challenges, in order to achieve a higher resolution in wafer-scaled lenses for mobile camera modules.

  • PDF

The relativity of the emitted light of discharge plasma and C02 laser output (방전 플라즈마 빛의 검출량과 CO2레이저 출력의 상관관계)

  • Kim, Tae-Kyun;Lee, Im-Geun;Choi, Jin-Young;Kim, Hee-Je
    • Proceedings of the KIEE Conference
    • /
    • 2004.07c
    • /
    • pp.1954-1956
    • /
    • 2004
  • Nowadays, $CO_2$ lasers are used widely in many applications such as materials fabrication, communications, remote sensing and military purpose etc. Especially, $CO_2$ lasers are in the spotlight at surface handling and heat processing. It is important to control the laser output power and beam Quality in those fields. And those are studied the important parameters deciding the fluctuation of laser beam are smoothing capacitor, frequency and the characteristics of laser resonator. But the study of plasma parameters of $CO_2$ lasers are little. So we detect the $CO_2$ laser from emitted $CO_2$ laser discharge plasma using a non-contact photo tansistor sensor and Low pass filter. In this study, The relativity of the emitted light of discharge plasma and CO2 laser output.

  • PDF

Development of the Computer Vision based Continuous 3-D Feature Extraction System via Laser Structured Lighting (레이저 구조광을 이용한 3차원 컴퓨터 시각 형상정보 연속 측정 시스템 개발)

  • Im, D. H.;Hwang, H.
    • Journal of Biosystems Engineering
    • /
    • v.24 no.2
    • /
    • pp.159-166
    • /
    • 1999
  • A system to extract continuously the real 3-D geometric fearture information from 2-D image of an object, which is fed randomly via conveyor has been developed. Two sets of structured laser lightings were utilized. And the laser structured light projection image was acquired using the camera from the signal of the photo-sensor mounted on the conveyor. Camera coordinate calibration matrix was obtained, which transforms 2-D image coordinate information into 3-D world space coordinate using known 6 points. The maximum error after calibration showed 1.5 mm within the height range of 103mm. The correlation equation between the shift amount of the laser light and the height was generated. Height information estimated after correlation showed the maximum error of 0.4mm within the height range of 103mm. An interactive 3-D geometric feature extracting software was developed using Microsoft Visual C++ 4.0 under Windows system environment. Extracted 3-D geometric feature information was reconstructed into 3-D surface using MATLAB.

  • PDF