• 제목/요약/키워드: Repetition Time

검색결과 459건 처리시간 0.036초

문자열의 근사커버 찾기 (Finding Approximate Covers of Strings)

  • 심정섭;박근수;김성렬;이지수
    • 한국정보과학회논문지:시스템및이론
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    • 제29권1호
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    • pp.16-21
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    • 2002
  • 반복적인 문자열에 대한 연구는 최근 들어 여러 분야에서 활발히 진행되어 왔다. 특히, DNA 염기서열의 분석 등 분자생물학에서 그 필용성이 대두되어 있다. 주기 커버, 시드 시퀘어 등이 반복적인 문자열의 대표적인 예들이다. 근사문자열 매칭 분야에서도 근사주기, 근사스퀘어 등 반복적인 문자열에 관 한 연구가 진행되고 있다. 본 논문에서는 근사커버의 개념을 제시한다. 길이가 각각 m, n 인 두 문자열 P. T가 주어졌을 때, P가 T의 근사커버가 되는 최소의 편집거리를 O(mn) 시간, 최소의 가중편집거리를 $O(mn^2)$시간에 찾는 알 고리즘을 제시한다. 또한 문자열 T만 주어졌을 때. T의 최소 근사커버 거리를 갖는 문자열 P를 찾는 문제가 NP-완전 결과임을 증명한다.

XLPE/EPR 계면의 부분방전 패턴 분석을 위한 신경망 모형 (Neural Network Model for Partial Discharge Pattern Analysis of XLPE/EPR Interface)

  • 조경순
    • 한국컴퓨터산업학회논문지
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    • 제6권2호
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    • pp.357-364
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    • 2005
  • 최근 들어 우리나라에서는 설치의 간편성과 높은 신뢰도를 가진 전력케이블의 사용이 증가하고 있다. 전력케이블은 출고 전에 IEEE std. 404-1993 시험을 거쳐 안정성을 확인하고 있지만 포설시 발생하는 접속부 내부의 결함으로 인하여 많은 문제가 발생하고 있다. 특히 불순물 혼입 또는 공극 발생시 고장율은 증가하게 된다 부분방전 검출은 포설 후 전력케이블의 상태를 관측할 수 있는 유용한 방법이다. 본 연구에서는 부분방전 특성을 평가하고자 케이블 접속재인 EPR과 케이블 절연체인 XPLE 사이에 인공 결함을 발생시킨 후 데이터 취득 시스템을 이용하여 $\Phi-q-n$ 특성을 검출하였으며, 부분방전의 정량적 해석을 위해 필요한 통계량을 계산하였으며, 신경망 모델을 적용하여 패턴 분석을 수행하여 $88\~96\%$의 구별이 가능하였다.

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소셜네트워크 서비스와 연상단어를 활용한 증강기억 시스템 (An Augmented Memory System using Associated Words and Social Network Service)

  • 김태완;박범준;박태근
    • 인터넷정보학회논문지
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    • 제11권6호
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    • pp.41-50
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    • 2010
  • 인간은 어떤 정보를 기억하려 노력하더라도, 시간이 지남에 따라 그 정보의 대부분을 잊어버린다. 반면에 인간은 사진을 보며 대부분 잊혀진 과거의 기억을 떠올릴 뿐만 아니라, 사진 속에 존재하는 특정 물체로부터 여러 단어들을 연상한 뒤, 그 연상된 단어로부터 새로운 기억을 떠올리곤 한다. 또한 이렇게 떠올린 기억으로 그 당시의 감성을 느끼기도 한다. 따라서 본 논문은 소셜 네트워크 서비스에 업로드된 사진들과 개인의 연상 단어 사전을 활용하여 사용자의 과거 회상에 도움이 되는 증강 기억 시스템을 제안한다. 제안하는 시스템에서 사용자가 특정 사진 속에 존재하는 물체를 선택하면, 그 물체와 관련된 연상 단어가 사용자에게 제공된다. 만일 사용자가 연상 단어중 하나를 선택하면, 제안하는 시스템은 해당 단어의 물체를 포함하는 다른 사진들의 목록을 사용자에게 제공함으로써, 사용자의 기억 회상을 돕고 감성을 자극할 수 있다. 본 논문에서 제안하는 시스템은 소셜 네트워크 서비스에서 보다 다양한 콘텐츠를 제공할 수 있을 것으로 기대 된다.

디지털 패턴의 생성과 공간적용방법 연구 - 디지털패턴의 생성을 중심으로 - (A Study on Spatial Application of Digital Modulation Patterns - Focusing on generating digital patterns -)

  • 박정주
    • 한국실내디자인학회논문집
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    • 제19권6호
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    • pp.100-111
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    • 2010
  • 'Pattern' is the term that is frequently used in the aspects of history, society, and science. It always appears in the remains or relics of the age of civilization when recording was started, and its evaluation and value differ by time. Patterns in the ancient civilization were symbolic, social, and spatially crucial. However, after the modernization, they were considered to be immoral and unnecessary, so the range of their significance came to reduce. Due to the development of science, ornament patterns lost the limitation of its range of use along with new interpretation of them. Especially with the advent of new scientific theories such as the evolution theory from the biological aspect, quantum mechanics, and super string theory, morphological possibilities more than the human scale perceived by men came to be discovered. Living organisms maintain their lives through patterns, structures, and processes in order to produce a system alive. Among them, patterns are the organization of relations determining the characteristics of the system. The present patterns may correspond to this meaning. The pattern in a space is the matter of how to relate the components after all. In a space, however, there are numerous components mingled with one another. If these tasks are conducted as analogue work, it will take a lot of time and effort. However, if digital media are utilized to perform the tasks like analysis, generation, or fabrication, it will produce a result with higher precision and efficiency. In this sense, parametric modeling is quite useful media. Opening morphological variation, it realizes more possibilities, connects conveniently the relations between complex components composing a space, and helps produce creative patterns.

병원 근무자의 요통 발생 요인에 관한 연구 (A Study on the Factors Affecting the Low Back Pain of Workers in Hospital)

  • 정진영;손경현
    • 대한물리치료과학회지
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    • 제16권3호
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    • pp.55-66
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    • 2009
  • Background: The purpose of this research was to investigate the factors affecting the low back pain of workers in hospital. 214 subjects waking at two general hospitals in Yosu city participated in this survey. Subjects consisted of doctors, nurses, medical engineers, officers and general laborers. The survey data were collected by a written questionnaire which made out by themselves for 25 days, from fourth August to 29th August, 2008. Methods: The questionnaire consisted of four categories, general, occupational, working habitual and the daily living characteristics. The collected data were analyzed by Chi-square test based on the present or absent of low back pain. Results: 1. In the general characteristics, low back pain had no significant relationship to all factors, sex, ago, body mass index, weight and height. 2. In the occupational characteristics, the phase of distribution of low back pain had statistical significant differences in the working hours a week, satisfaction of pay, satisfaction of occupation(p<0.05). However low back pain did not significantly related to the kind of occupation, period of work and degree of stress. 3. In the habitual characteristics, low back pain was significantly influenced by working posture, frequency of using lumbar and heavy material lifting, monotonous repetition of working operation and noise(p<0.05). No significant difference was shown in the factor of convenience of chair. 4. In the daily living characteristics, low back pain shown the significant differences in walking time a day, status of health and smoking pattern(p<0.05). there were, however, no significant differences in the aspect of the kind of house and bed, sleeping attitude, driving, riding time on the vehicle, exercising, frequency of cultural life and drinking alcohol. Conclusion: when I see above resultants totally, it appears a higher incidence caused by working environment rather than living habit and then consequently compared to hospital workers, they also have high incidence like others. In order to reduce incidence of low back pain and enjoy the our life we need to educate ourselves preventing program for low back pain and try to effort for preventing of low back pain on each department and individual.

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Repeat analysis of intraoral digital imaging performed by undergraduate students using a complementary metal oxide semiconductor sensor: An institutional case study

  • Yusof, Mohd Yusmiaidil Putera Mohd;Rahman, Nur Liyana Abdul;Asri, Amiza Aqiela Ahmad;Othman, Noor Ilyani;Mokhtar, Ilham Wan
    • Imaging Science in Dentistry
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    • 제47권4호
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    • pp.233-239
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    • 2017
  • Purpose: This study was performed to quantify the repeat rate of imaging acquisitions based on different clinical examinations, and to assess the prevalence of error types in intraoral bitewing and periapical imaging using a digital complementary metal-oxide-semiconductor(CMOS) intraoral sensor. Materials and Methods: A total of 8,030 intraoral images were retrospectively collected from 3 groups of undergraduate clinical dental students. The type of examination, stage of the procedure, and reasons for repetition were analysed and recorded. The repeat rate was calculated as the total number of repeated images divided by the total number of examinations. The weighted Cohen's kappa for inter- and intra-observer agreement was used after calibration and prior to image analysis. Results: The overall repeat rate on intraoral periapical images was 34.4%. A total of 1,978 repeated periapical images were from endodontic assessment, which included working length estimation (WLE), trial gutta-percha (tGP), obturation, and removal of gutta-percha (rGP). In the endodontic imaging, the highest repeat rate was from WLE (51.9%) followed by tGP (48.5%), obturation (42.2%), and rGP (35.6%). In bitewing images, the repeat rate was 15.1% and poor angulation was identified as the most common cause of error. A substantial level of intra- and inter-observer agreement was achieved. Conclusion: The repeat rates in this study were relatively high, especially for certain clinical procedures, warranting training in optimization techniques and radiation protection. Repeat analysis should be performed from time to time to enhance quality assurance and hence deliver high-quality health services to patients

텔레비젼 유아교육(幼兒敎育) 프로그램에 관(關)한 탐색적(探索的) 연구(硏究) (Educational Television Programs for Early Childhood: Explorative Study)

  • 지옥정;전경숙
    • 아동학회지
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    • 제3권
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    • pp.83-96
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    • 1982
  • TV has a very strong influence on various aspects of children's life and development. In view of this influence, various problems related to the content and production of TV programs for early - childhood deserve a careful study. Recognizant of this significance, this study aims to suggest the direction in which the production of TV programs for early childhood in Korea will steer by defining the concept of TV programs for early childhood and by analyzing the current status and trends of producting TV program for early childhood at abroad. In this study, attempts were made to suggest some strategies for the production of TV programs for early childhood based on an expansive literature review. 1. The running time of TV programs for early-childhood ages of 4-5 year old is suggested to be 15 minutes. 2. In the process of producing the programs, a group of professionals including in-service teachers, researchers specializing in child development, psychology and sociology, idea-creators, script writers, media experts, producers, and monitors should provide concerted efforts throughout the process. 3. The running time of TV programs for early-childhood should be less than 20 minutes and therefore should have simple learning objectives. 4. The contents of programs should be organized in such a way as to enable children to view themselves as well as the environment in more positive ways and to fester desirable values and beliefs in them based on various constructive activities and plays. 5. The programs should adopt various techniques including repetition, to ensure the maximum learning effect in full consideration of children's interest. 6. The programs should be continuously revised and supplemented based on the evaluation of the programs, children's responses and monitor's feedbacks.

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냉간 금형용 공구강의 Cu 전극을 이용한 방전 탭에 관한 연구 (A Study on the Electrical Discharge Machining Tap by using Cu Electrodes of the Cold-Work Tool Steel)

  • 이은주;박인수;김후권;왕덕현;정한식;이광성
    • 한국기계가공학회지
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    • 제15권5호
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    • pp.131-136
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    • 2016
  • Currently, an EDM tapping procedure has comprised some parts of the engraving discharge process for the press die. Usually, tapping has been used in cases where we are unable to mechanically machine using steelwork processes due to an increase in the hardness of a material after heat treatment in relation to a design change or missing process. Here, we analyze the influence of discharge tap shape on discharge time, discharge current, and the number of repetition conditions when a cold-work tool steel (STD11) has been treated with a discharge tapped by a screw-shaped cu electrode. The most important influence on processing condition has been determined to be the number of discharge repetitions. As this number increases, the angle reduction of a thread closes to an angle of the electrode via a power generation reduction. The optimal combination of conditions has been determined to be three discharge repetitions, $180{\mu}s$ of discharge time (same as existing regulations), and 25.4A of peak current. A 0.2749db advantage has emerged after comparing between this combination of optimal conditions and the SN rate of existing regulations.

Fast Precessional Motion of Co/Pd Multilayer Systems Induced by Heat Treatment

  • Sohn, Jeong-Woo;Lee, Kyeong-Dong;Song, Hyon-Seok;Kim, Seon-Ock;Kim, Ji-Wan;Jeong, Jae-Woo;Shin, Sung-Chul
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2010년도 임시총회 및 하계학술연구발표회
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    • pp.94-94
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    • 2010
  • Co/Pd multilayer systems have been investigated with much attention for a long time due to the high and easily controllable perpendicular magnetic anisotropy. Two [Pd(1)/Co(0.4 nm)]5 multilayer systems - one is as-deposit, and the other is annealed at $350^{\circ}C$ - are studied with an all-optical approach. A two-color optical pump probe setup using 30 fs laser pulse at 82 MHz repetition rate is used to measure the time-resolved magneto-optical Kerr signal. It turns out the heat treatment enhances the perpendicular magnetic anisotropy, and leads to faster magnetization precession. The frequency reaches 30 GHz in the annealed sample, which is a factor of 2 larger compared to the as-deposit film.

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The effect of hip abductor fatigue on static balance and gait parameters

  • Hwang, Wonjeong;Jang, Jun Ha;Huh, Minjin;Kim, Yeon Ju;Kim, Sang Won;Hong, In Ui;Lee, Mi Young
    • Physical Therapy Rehabilitation Science
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    • 제5권1호
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    • pp.34-39
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    • 2016
  • Objective: Hip abductors play a role in providing stability and movement to the lower limbs. The purpose of this study was to examine the effects of hip abductor fatigue on static balance and gait in the general population. Design: One group pre-test post-test design. Methods: Thirteen university students in their twenties volunteered for the study and had underwent a functional assessment. To induce fatigue, the subjects were instructed to raise their dominant lower extremity up against a load of 50% of 1 repetition maximum while producing hip abduction in a side-lying position. Subjects were instructed to maintain an abduction speed of 30 repetitions per minute to induce fatigue. Muscle fatigue was considered to be established when subjects were unable to perform hip abduction three consecutive times along with the metronome. A post-test of balance and gait was performed immediately in order to prevent fatigue recovery. The center of pressure (COP) distance area was measured using the Zebris FDM-S Multifunction Force measuring plate. Gait performance was analyzed using the GAITRite. Results: The COP distance was increased after fatigue was induced. There was a significant increase in the standard deviation of the medio-lateral and antero-posteror distance (p<0.05). Although there was no significant difference in gait parameters, there was a significant decrease in single support time after fatigue was induced (p<0.05). Conclusions: There was an increase in static balance instability and a significant decrease in single support time during gait due to hip abductor muscle fatigue.