• 제목/요약/키워드: Hand-Held Device

검색결과 61건 처리시간 0.03초

이기종 협력 통신시스템에서 디코딩 전력소모 감소를 위한 인위적인 주파수 오프셋을 이용한 패킷 구별 기법 (Packet Discrimination Method Using Artificial Frequency Offsets for Low Decoding Power Consumption in Heterogeneous Cooperative Communication Systems)

  • 채승엽;여규학;임민중
    • 한국통신학회논문지
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    • 제39A권7호
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    • pp.372-379
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    • 2014
  • 배터리의 제한이 있는 이동통신 단말이 이동통신이 아닌 무선LAN(Local Area Network)또는 고속 무선PAN(Personal Area Network)등의 근거리 무선통신 시스템을 이용하여 주변에 위치한 전력이 풍부한 디바이스의 릴레이 동작을 통해 데이터를 송수신 한다고 가정할 때 단말은 송신거리 감소에 의해서 전력소모를 줄일 수 있다. 하지만 단말 주변에 매우 많은 무선LAN 및 고속 무선PAN시스템이 존재할 경우 자신과 상관없는 패킷을 수신함으로써 또다른 전력소모 문제가 발생한다. 본 논문에서는 이러한 문제를 해결하기 위해 물리계층에 주파수 오프셋을 이용한 ID를 넣으므로써 불필요한 패킷 수신을 회피하여 전력소모를 줄일 수 있는 방법을 제안하며 이 방법을 이용하였을 때 최적의 물리계층 ID개수를 찾는다.

해양레저 안전장비 개발 (Development of Safety Devices for Marine Leisure)

  • 구자영;임정빈;이재응;남택근;정중식;박성현;양원재;안영섭
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 춘계학술대회 및 창립 30주년 심포지엄(논문집)
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    • pp.241-246
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    • 2006
  • 이 논문에서는 안전한 해양레저 행위를 지원하기 위한 두 가지 개인 휴대용 전자장치 개발 내용을 기술한다. 하나는 조난자를 신속히 민-관-군 동시 다발적으로 수색하기 위한 선박용 9GHz 대역의 일반 레이더 전파에 응답하는 레이더 응답장치이다. 다른 하나는 조난자의 위치를 추적하고 식별할 수 있는 900MHz 스펙트럼 확산 주파수 홉핑 방식의 송수신기와 GPS를 이용한 해상 무선식별장치 개념의 전자장치이다. 해양경찰 함정을 이용한 해상에서의 다양한 현장실험을 통하여 두 가지 장비의 성능을 확인하였다. 그리고 향후 상용화 방안에 대해서 검토하였다.

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Wearable Computers

  • Cho, Gil-Soo;Barfield, Woodrow;Baird, Kevin
    • 섬유기술과 산업
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    • 제2권4호
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    • pp.490-508
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    • 1998
  • One of the latest fields of research in the area of output devices is tactual display devices [13,31]. These tactual or haptic devices allow the user to receive haptic feedback output from a variety of sources. This allows the user to actually feel virtual objects and manipulate them by touch. This is an emerging technology and will be instrumental in enhancing the realism of wearable augmented environments for certain applications. Tactual displays have previously been used for scientific visualization in virtual environments by chemists and engineers to improve perception and understanding of force fields and of world models populated with the impenetrable. In addition to tactual displays, the use of wearable audio displays that allow sound to be spatialized are being developed. With wearable computers, designers will soon be able to pair spatialized sound to virtual representations of objects when appropriate to make the wearable computer experience even more realistic to the user. Furthermore, as the number and complexity of wearable computing applications continues to grow, there will be increasing needs for systems that are faster, lighter, and have higher resolution displays. Better networking technology will also need to be developed to allow all users of wearable computers to have high bandwidth connections for real time information gathering and collaboration. In addition to the technology advances that make users need to wear computers in everyday life, there is also the desire to have users want to wear their computers. In order to do this, wearable computing needs to be unobtrusive and socially acceptable. By making wearables smaller and lighter, or actually embedding them in clothing, users can conceal them easily and wear them comfortably. The military is currently working on the development of the Personal Information Carrier (PIC) or digital dog tag. The PIC is a small electronic storage device containing medical information about the wearer. While old military dog tags contained only 5 lines of information, the digital tags may contain volumes of multi-media information including medical history, X-rays, and cardiograms. Using hand held devices in the field, medics would be able to call this information up in real time for better treatment. A fully functional transmittable device is still years off, but this technology once developed in the military, could be adapted tp civilian users and provide ant information, medical or otherwise, in a portable, not obstructive, and fashionable way. Another future device that could increase safety and well being of its users is the nose on-a-chip developed by the Oak Ridge National Lab in Tennessee. This tiny digital silicon chip about the size of a dime, is capable of 'smelling' natural gas leaks in stoves, heaters, and other appliances. It can also detect dangerous levels of carbon monoxide. This device can also be configured to notify the fire department when a leak is detected. This nose chip should be commercially available within 2 years, and is inexpensive, requires low power, and is very sensitive. Along with gas detection capabilities, this device may someday also be configured to detect smoke and other harmful gases. By embedding this chip into workers uniforms, name tags, etc., this could be a lifesaving computational accessory. In addition to the future safety technology soon to be available as accessories are devices that are for entertainment and security. The LCI computer group is developing a Smartpen, that electronically verifies a user's signature. With the increase in credit card use and the rise in forgeries, is the need for commercial industries to constantly verify signatures. This Smartpen writes like a normal pen but uses sensors to detect the motion of the pen as the user signs their name to authenticate the signature. This computational accessory should be available in 1999, and would bring increased peace of mind to consumers and vendors alike. In the entertainment domain, Panasonic is creating the first portable hand-held DVD player. This device weight less than 3 pounds and has a screen about 6' across. The color LCD has the same 16:9 aspect ratio of a cinema screen and supports a high resolution of 280,000 pixels and stereo sound. The player can play standard DVD movies and has a hour battery life for mobile use. To summarize, in this paper we presented concepts related to the design and use of wearable computers with extensions to smart spaces. For some time, researchers in telerobotics have used computer graphics to enhance remote scenes. Recent advances in augmented reality displays make it possible to enhance the user's local environment with 'information'. As shown in this paper, there are many application areas for this technology such as medicine, manufacturing, training, and recreation. Wearable computers allow a much closer association of information with the user. By embedding sensors in the wearable to allow it to see what the user sees, hear what the user hears, sense the user's physical state, and analyze what the user is typing, an intelligent agent may be able to analyze what the user is doing and try to predict the resources he will need next or in the near future. Using this information, the agent may download files, reserve communications bandwidth, post reminders, or automatically send updates to colleagues to help facilitate the user's daily interactions. This intelligent wearable computer would be able to act as a personal assistant, who is always around, knows the user's personal preferences and tastes, and tries to streamline interactions with the rest of the world.

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보행자 추측 항법 성능 향상을 위한 스마트폰 전용 모션 센서 보정 알고리즘 (Correction Algorithm for PDR Performance Improvement through Smartphone Motion Sensors)

  • 김도윤;최린
    • 정보과학회 컴퓨팅의 실제 논문지
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    • 제23권3호
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    • pp.148-155
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    • 2017
  • 본 논문에서는 스마트폰 내 가속도, 자기장, 자이로스코프 센서들을 이용해 사용자의 걸음과 걸음 수를 인식하는 시스템을 개발하였다. 센서 데이터 분석을 통해 사용자의 걸음을 스마트폰을 손에 든 상황과 주머니에 넣은 상황에서의 걸음 패턴으로 분류하고 이를 추출할 수 있는 알고리즘을 사용하여 걸음 수 인식의 정확성을 개선하였다. 알고리즘을 적용한 결과 손에든 상황에서 96%, 주머니에 넣은 상황에서 95.5% 수준의 걸음 수 인식 정확도를 보였으며, 나머지 터치 스크린, 위아래 반복 흔들기, 앉아서 일어서기, 오른쪽 왼쪽 흔들기와 같은 행위로 인해 발생하는 6%의 오차를 확인하였다.

휴대용 장치를 위한 필름형 촉감 액추에이터 (A Film-type Vibrotactile Actuator for Hand-held Devices)

  • 김상연;김기백;김재환;박원형;경기욱
    • 로봇학회논문지
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    • 제8권3호
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    • pp.150-155
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    • 2013
  • Vibrotactile actuators for small consumer electronic products, such as mobile devices, have been widely used for conveying haptic sensation to users. One of the most important things in vibrotactile actuators is to be developed in the form of thin actuator which can be easily embedded into mobile devices and to provide vibrotactile signals with wide frequency band to users. Thus, this paper proposes a thin film type haptic actuator with an aim to convey vibrotactile information with high frequency bandwidth to users in mobile devices. To this end, a vibrotactile actuator which creates haptic sensation is designed and constructed based on cellulose acetate material. A cellulose acetate material charged with an electric potential can generate vibration under the AC voltage input. It is found that the motion of the actuator can have concave or convex shape by controlling a polarity of both charged membranes and the actuator performance can be modulated by increasing level of biased electric potential. The experiment clearly shows that the proposed actuator creates enough output force to stimulate human skin with a large frequency bandwidth and to simulate various vibrotactile sensations to users.

무선 센서 네트워크를 이용한 현장 견학의 그룹 관리 시스템 (Group Control System for Field Trip using Wireless Sensor Networks)

  • 정경권;이승준;김민철;경여선;엄기환
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2010년도 추계학술대회
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    • pp.489-492
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    • 2010
  • 본 논문은 무선 센서 네트워크를 이용한 현장 견학의 그룹 관리 시스템을 제안한다. 각 그룹을 담당하는 선생님은 휴대형 장치를 이용하여 아이들을 관리하고, 확인할 수 있고, 아이가 그룹을 벗어났을 때 감지할 수 있다. 아이들은 센서 노드를 사용하여 5초마다 패킷을 전송하고, 선생님 주변 30m 이내에 위치하도록 한다. 선생님은 아이들을 관리하고, 없어진 아이들을 확인할 수 있다. 제안한 시스템은 현장 견학뿐만 아니라 수학여행이나 소풍에 사용될 수 있다.

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구법(灸法)과 intense pulsed light(IPL)의 특성 비교 및 광선구(光線灸)의 한방임상(韓方臨床) 활용(活用) (Comparison between Moxibustion and the Intense Pulsed Light (IPL) and the Clinical Application of Photo-moxa)

  • 장인수;선승호;남동현;금수연;서형식
    • 한방안이비인후피부과학회지
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    • 제23권3호
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    • pp.78-83
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    • 2010
  • Objectives : The purpose of this study is to compare the principles between moxibustion and the 'Intense pulsed light (IPL)' and to investigate the clinical application of the photo-moxa for the Korean medicine fields. Methods : The characteristics of moxibustion, IPL, parabolic reflector moxa and the dermatology surgical use of moxibustion were reviewed in the literature. Results : IPL is one type of light treatments that is employed by radiating the short-pulse wave, which is transformed from the light of high intensity. There has been used parabolic reflector in Asia for more than 2,000 years, and this hand-held device used for moxibustion in traditional medicine. Moxibustion is one of the treatment tools in Korean medicine using the heat energy. The fluence or energy density of IPL in clinical circumstances is similar to parabolic reflector moxa of moxibustion. IPL and parabolic reflector moxa shared same treatment principle employing the heat energy. Therefore IPL could apply for many indications in Korean medicine as a moxibustion tool and acupuncture. Conclusions: IPL may be plausible to be a fascinate method in phototherapy of Korean medicine.

휴대용 RFID 리더기를 활용한 분실 의료자산 최적 검색 경로 결정과 천정 고정식 리더기 설치위치 선정 방안 연구 (A Study on Optimal Searching Path Using Handheld RFID Reader and Deployment of a Stationary Reader to Maximize the Efficiency of the Search Process for Missing Medical Assets)

  • 김각규;조성진;윤봉규
    • 한국경영과학회지
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    • 제37권4호
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    • pp.95-109
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    • 2012
  • Being able to quickly locate valuable medical equipment is critical inside hospitals. In order to utilize limited budget and resources efficiently, accurate locating or tracking is required in many fields. In this research, we focus on how to find the location of missing assets by using RFID in real time indoors to track equipment. When equipment needs to be searched, the purpose of a RFID device is to minimize the time, investment cost and effort spent searching for the equipment. Thus, this research presents a mathematical model of using RFID (both handheld reader and stationary reader) for efficient asset location. We derive the expected time of locating RFID-tagged objects in a multi-area environment where hand-held RF readers are used. We then discuss where to deploy stationary RF readers in order to maximize the efficiency of the search process.

Comparison of the Electromyographic Activity of the Tibialis Anterior and Isometric Dorsiflexor Strength during Dorsiflexion According to Toe Postures in Individuals with Ankle Dorsiflexor Weakness

  • Jeon, In-Cheol
    • The Journal of Korean Physical Therapy
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    • 제32권4호
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    • pp.233-237
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    • 2020
  • Purpose: This study compared the electromyographic activity of the tibialis anterior (TA) and isometric dorsiflexor strength during dorsiflexion according to the toe postures in individuals with ankle dorsiflexor weakness. Methods: Twenty subjects with ankle dorsiflexor weakness participated in this study. The electromyographic activity of the TA and isometric dorsiflexor strength during dorsiflexion between with toe flexion, extension, and neutral postures were measured using an electromyography device and a hand-held dynamometer in individuals with ankle dorsiflexor weakness. One-way repeated measured analysis of variance, and a Bonferroni post hoc test was used. The level of statistical significance was set to α=0.01. Results: The electromyographic activity of the TA was greater with toe flexion during dorsiflexion than with toe extension and neutral postures (p<0.01). The isometric dorsiflexor strength was smaller with toe flexion during dorsiflexion than with toe extension and neutral postures (p<0.01). Conclusions: In individuals with ankle dorsiflexor weakness, the dorsiflexion with toe flexion can help improve the TA electromyographic activity. The toe posture during dorsiflexion for selective TA activation should be considered, especially in individuals with ankle dorsiflexor weakness.

형광과 여기광을 공간적으로 분리하는 바이오칩용 소형 형광측정시스템 (Miniature Biochip Fluorescence Detection System with Spatial Separation of Fluorescence from Excitation Light)

  • 김호성;김용권;박주한;이국녕;최재호
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제54권8호
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    • pp.378-383
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    • 2005
  • We report the development of miniature fluorescence detection systems that employ miniature prism, mirrors and low coat CCD camera to detect the fluorescence emitted from 40 fluorescently-labeled protein patterns without scanner. This kind of miniature fluorescence detection system can be used in point of care. We introduce two systems, one uses prism+mirror block and the other uses prism and two mirrors. A large NA microscope eyepiece and low cost CCD camera are used. We fabricated protein chip containing multi-pattern BSA labeled with Cy5, using MEMS technology and modified the surface chemically to clean and to immobilize proteins. The measurements show that the combination of prism and mirrors can homogenize elliptical excitation light over the sample with higher optical efficiency, and increase the separation between excitation and fluorescence light at the CCD to give higher signal intensity and higher signal to noise ratio. The measurements also show that protein concentrations ranging from 10 ng/ml to 1000 ng/ml can be assayed with very small error. We believe that the proposed fluorescence detection system can be refined to build a commercially valuable hand-held or miniature detection device.