• Title/Summary/Keyword: blind study

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A Study on Efficient ID-based Partially Blind Signature (효율적인 ID 기반 부분은닉서명에 관한 연구)

  • 김현주;오수현;원동호
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.13 no.6
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    • pp.149-161
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    • 2003
  • Partially blind signature scheme allows the signer to insert non-removable common information into his blind signature. Blind signatures providing with both users privacy and data authenticity are one of key parts of information systems, such anonymous electronic cash and electronic voting as typical examples. Partially blind signature, with which all expired e-cash but for still-alive can be removed from the banks database, copes well with the problem of unlimited growth of the banks' database in an electronic cash system. In this paper we propose an efficient ID-based partially blind signature scheme using the Weil-pairing on Gap Diffie-Hellman group. The security of our scheme relies on the hardness of Computational Diffie-Hellman Problem. The proposed scheme provides higher efficiency than existing partially blind signature schemes by using three-pass protocol between two participants, the signer and requesters also by reducing the computation load. Thus it can be efficiently used in wireless environment.

A Study on the Analysis of the Current and the Demand of the House for the Blind (시각장애인 주택의 실태 및 요구도 분석에 관한연구)

  • Kim, Sang-Woon;Kang, Byoung-Keun;Soong, Ki-Chang;Park, Kwang-Jae;Yun, Young-Sam;Jung, Eun-Young
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.15 no.1
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    • pp.41-52
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    • 2009
  • Increasing the old and the senile disability, it is increased that the demand of barrier-free house for the disabled, the senior, the pregnant and the young is strongly increasing recently. In this reason, this study focuses the problems of the house which is used by the Blind through the investigation of current status and tries to find out the differences between disability's demand and current design of their house. As well, through the research and analysis some cases of the residential alterations this study verifies what the demand is on each room and their need is committed correctly during the residential alterations. It is the purposes of this study finding the problems through these research and analysis. Thus this study investigates houses of the Blind and finds out their house type, scale and daily life through the statistical data and documentary survey and also, investigates current status of their house. The basic standard for the current status and the demand analysis is researched by the barrier factors which are deducted from the former study.

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Comparing the effectiveness of ultrasound guided versus blind genicular nerve block on pain, muscle strength with isokinetic device, physical function and quality of life in chronic knee osteoarthritis: a prospective randomized controlled study

  • Cankurtaran, Damla;Karaahmet, Ozgur Zeliha;Yildiz, Sadik Yigit;Eksioglu, Emel;Dulgeroglu, Deniz;Unlu, Ece
    • The Korean Journal of Pain
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    • v.33 no.3
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    • pp.258-266
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    • 2020
  • Background: The genicular nerve block (GNB) is demonstrated from several reports to alleviate pain and improve knee functionality in patients with chronic knee osteoarthritis (OA). Ultrasound (US)-guided GNB has been the most used imaging method. This study aimed to compare the effectiveness of US-guided versus blind GNB in the treatment of knee OA. Methods: This prospective, randomized clinical trial included patients with knee OA based on American College of Rheumatology diagnostic criteria. The patients were evaluated for clinical and dynamometer parameters at the baseline, 4 weeks after treatment, and 12 weeks after treatment. The patients underwent blind injection or US-guided injection. Results: When compared with the baseline, both groups showed significant improvement in pain, physical function, and quality of life parameters. Significant differences were observed between the groups for clinical parameters (30-second chair stand test, 6-minute walk test) in favor of the US-guided group. On the other hand, blind injection was more significantly effective on some parameters of the Nottingham Health Profile. There wasn't any significant improvement in isokinetic muscle strength for either group. Conclusions: This study demonstrated that both US-guided and blind GNB, in the treatment of knee OA, were effective in reducing symptoms and improving physical function. GNB wasn't an effective treatment for isokinetic muscle function. US-guided injections may yield more effective clinical results than blind injections.

Cable-supported Bridge Safety Inspection Blind Spot Elimination Technology using Drones (드론을 활용한 케이블지지교량 안전점검 사각지대 해소 기술)

  • Sungjin Lee;Bongchul Joo;Jungho Kim
    • Journal of Korean Society of Disaster and Security
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    • v.15 no.4
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    • pp.31-38
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    • 2022
  • In the case of special bridges whose superstructure is supported by cables, there are many blind spots that are difficult to access without special equipment and personnel. As a result, there are difficulties in the safety inspection of special bridges. The purpose of this study is to review the inspection blind spots of cable-supported bridges such as cable-stayed bridges and suspension bridges, and to study ways to eliminate blind spots using drones. To this end, the cables, stiffened girder, and pylons of the cable-stayed bridge located in the sea were inspected using drones. Through this study, it was confirmed that external safety inspection of special bridges that are difficult for inspectors to access is possible using drones. In particular, drone inspection to check the external condition and damage of the pylon, which is a blind spot for inspection of special bridges, is a very effective safety inspection method.

An Experimental Study of a Blind Identification Algorithm for Underwater Acoustic Channel Estimation (수중음향 채널추정을 위한 Blind Identification 알고리듬의 실험적 연구)

  • Choi Youngchol;Kim Sea-Moon;Lim Yong-kon
    • Proceedings of the Acoustical Society of Korea Conference
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    • autumn
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    • pp.401-404
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    • 2004
  • 수중음향통신 관점에서 바다와 같은 수중채널은 수십심벌에 이르는 다중경로와 빠르게 변화하는 도플러 효과가 존재한다. 따라서 신뢰성 있는 수중음향통신을 위해서는 채널 등화가 반드시 필요하다. 본 논문에서는 이차 통계량 기반의 Blind Identification 알고리듬을 이용한 수중음향 채널추정 기법을 이용하여 무향수조의 채널응답을 분석하였다. 실험을 통하여 알고리듬의 추정 정확도 및 트랜스듀서 특성을 포함한 무향수조의 채널 응답 특성에 대하여 논한다.

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A study on locomotion module of mobile robot for the blind guidance (맹인 안내용 mobile robot의 locomotion module에 관한 연구)

  • 김병수;신중섭;홍승홍
    • 제어로봇시스템학회:학술대회논문집
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    • 1986.10a
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    • pp.592-595
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    • 1986
  • This paper presents a mobile of robot (for the blind) commanded by written course route on MAP. Its locomotion module is composed of PWM motor driving unit, wheel's rotation measurement unit and display and keyboard unit. In algorithm, "COMMAND" and "NEXT PREDICTED POSITION" for locomotion are computed from the MAP and the next position is compared with the measured one. Also, locomotion method for the convenience of the blind is discussed and experimentally demonstrated. In the experiment, the average speed of robot is 0.4m/sec and the computation error of the map is negligible.

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A Basic Study of Cane To Assist Blind Walker with ultrasonic Sensor (초음파 센서를 이용한 시각장애자용 보행유도 지팡이에 관한 기초연구)

  • Kim, S.Y.;Kim, D.W.
    • Proceedings of the KIEE Conference
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    • 2002.11c
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    • pp.411-413
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    • 2002
  • In this paper we researched about the ultrasonic cane which aids the blind to walk. We used ultrasonic in recognizing the object and implemented pulse counting method in measuring the distance. The distance measuring system consists of transmitter unit, receiver unit and micro-processor. We used broadband ultrasonic sensors in transmitter unit and receiver unit. The blind is able to recognize the distance between obstacles and himself as it used a vibration system.

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A Study of Korean TTS Listening Speed for the Blind Using a Screen Reader (스크린리더를 사용하는 시각장애인의 한국어 합성음 청취속도 연구)

  • Lee, Heeyeon;Hong, Ki-Hyung
    • Phonetics and Speech Sciences
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    • v.5 no.3
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    • pp.63-69
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    • 2013
  • The purpose of this study was to evaluate the maximum and optimal listening speed of Korean TTS for the blind. Five blind participants took part in this study. The instruments used in this study were 17 sentence sets (2 sets for an excercise, 10 sets for a repeated test, and 5 sets for a random test), with short meaningful sentences (the same sentences for the repeated test, different sentences for the random test) with 15 differentiated speeds (Range=0.8-3.6, SD=0.2). Each participant's maximum and quickest listening speeds were calculated by objective recall accuracy (determined by the number of correctly recalled syllables/the total number of syllables in a sentence X 100) and subjective recall accuracy (recall accuracy judged by each participant's subjective evaluation). The results showed that the participants' recall accuracy had a tendency to increase as the TTS speed decreased. Participants' subjective recall accuracy was higher than objective recall accuracy in the repeated tests and vice versa in the random tests. The results also revealed that the participants' sentence familiarity had an influence on their Korean TTS listening speed.

Actual Use and Characteristics of Clues for Blind Person's Independent Walking - Case Study of Kansai Region in JAPAN - (전맹인의 단독 보행을 유도하는 단서 사용실태와 특성 - 일본 간사이(關西) 지방 사례를 중심으로 -)

  • Cho, Minjung;Chie, Murosaki
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.18 no.1
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    • pp.15-23
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    • 2012
  • The purpose of this research is support blind person's daily walking. In order to achieve the purpose, we investigate how the environmental information is used for their daily walking both in residential and commercial areas considering the characteristics of walking. In the investigation, interview to the persons concerned is carried out and all the conversation with them is recorded with a voice recorder. Moreover, the environmental information that may become clues is plotted on a map together with photos. The results are as follows; (1) Environmental information which the blind persons use is different depending on the role of its own of place, such as place confirmation, direction decision, distance understanding. (2) It is demonstrated that the information acquisition from sound is effective when they especially understand place and location.

A Study on Performance Comparison of Bussgang-type Adaptive Blind Algorithms (Bussgang계열의 적응 Blind 알고리듬들의 성능비교에 관한 연구)

  • Kim, Hyoung-Seok;Kang, Hyun-Cheol;Byun, Youn-Shik
    • The Journal of the Acoustical Society of Korea
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    • v.14 no.5
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    • pp.20-28
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    • 1995
  • This paper studied adaptive blind equalizer which belong to Bussgang type. It is well known that blind equalizer performs equalization without using a training sequence. Especially, this paper concentrated on real time processing of them. The channel characteristic was obtained from measurements taken in a real urban multipath environment. A T/2 fractionally-spaced equalizer was used at the receiving end. Our computer simulations demonstrated that Stop and Go, Benveniste-Goursat, and optimal Bussgang algorithms have relatively low MSE property. CMA shows faster convergence property than any other of Bussgang type algorithm.

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