• Title/Summary/Keyword: 차이와 반복

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A Study on the melting Characteristics of Fuse Element by Repeating Overcurrent (반복과전류에 의한 퓨즈 엘리먼트의 용단특성에 관한 연구)

  • Kim, Youn-Hyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.2
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    • pp.120-126
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    • 2010
  • This paper propose analysis and examination of the melting characteristic of fuse elements by repeating overcurrent as a depletion factor of high pressure current limiting fuse through test following existence and nonexistence of extinction material and various configuration of elements. To examine deterioration progress rate by repeating overcurrent we analyzed heat for various element notching configuration, designed plate type, ring type element and estimated the relationship with life span by analyzing breaking characteristic through repeating overcurrent test with adjusting load factor at Silicon Dioxide(SiO2) filled state or in air. A Crack by repeat stress, decrease of section and transformation by friction with extinction material by repeating overcurrent causes a problem which shortens life span based on fuse repeating frequency. Since the contents of this paper might be useful to research the correlation between friction of materials and repeating life span based on load factor of repeating current, the quality of product would be improved through solution of the problem.

3-Dimensional Design Failure Curve of Marine Silty Sand under Different Confining Pressures Subjected to Cyclic Loading (반복하중을 받는 해양 실트질 모래의 구속압에 따른 3차원 설계파괴곡선 산정)

  • Suwon, Son;Jongchan, Yoon;Jinman, Kim
    • Journal of the Korean GEO-environmental Society
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    • v.23 no.12
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    • pp.25-31
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    • 2022
  • Unlike structures installed on land, the structures installed on the offshore ground must consider long-term cyclic loads such as wave loads, wind loads and tidal loads at sea. Therefore, it is important to analyze the behavior of the ground subjected to long-term cyclic loads in order to design a structure installed on the ocean ground. In this paper, cyclic simple shear tests were performed to analyze the ground behavior for long-term cyclic loads according to the confining pressure, and a three-dimensional design failure curve was prepared that can easily check the failure characteristics according to the confining pressure. As a result of the analysis, it was confirmed that the position of the design failure curve is different depending on the confining pressure even under the same conditions of the cyclic shear stress ratio and the average shear stress ratio, and the number of cyclic loads reaching failure is affected by the confining pressure. From the created 3-D design failure curve under different confining pressure, the tendency and approximate value of the design failure curve according to the confining pressure can be estimated.

Comparison of the Repetitive Nerve Stimulation Test(RNST) Findings Between in Upper and Lower Extremity Muscles in Myasthenia Gravis (중증근무력증 진단시 상지와 하지근육들에서의 반복신경자극검사 양성률의 비교)

  • Jung, Yun Seuk;Lee, Jun;Lee, Se Jin;Hah, Jung Sang;Kim, Wook Nyeon
    • Journal of Yeungnam Medical Science
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    • v.17 no.2
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    • pp.129-136
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    • 2000
  • Background and Purpose: This study was undertaken to compare the sensitivity of the Repetitive Nerve Stimulation Test (RNST) between the upper and lower extremity muscles in myasthenia gravis(MG) patients. Material and Methods: The study population consisted of 20 normal persons(control group) and 10 MG patients(MG group). Using Stalberg's method. RNST was systemically performed in orbicularis oculi muscle. upper extremity muscles(flexor carpi ulnaris. abductor digiti quinti), and lower extremity muscles(tibialis anterior. extensor digitorum brevis. vastus medialis). Results: There were statistical differences of decremental response($mean{\pm}SD$) in orbicularis oculi and upper extremity muscles between the control and MG groups(p<0.05 or p<0.01). However, there was no statistical difference of decremental response($mean{\pm}SD$) to RNST in lower extremity muscles between the control and MG groups. There were highersensitivity in orbicularis oculi and upper extremity muscles than lower extremity muscles. Although positive reponse were detected in the lower extremity muscles, the positive response rates of lower extremity muscles were lower than o.oculi and upper extremity muscles. Conclusions: When the response rates of RNST in facial and upper extremity muscles are normal, may not be required RNST in lower extremity muscles.

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Comparison of microleakage after load cycling for nanofilled composite resin fillings with or without flowable resin lining (Nanofilled 복합레진으로 와동 충전 시 flowable 레진 사용 유무에 따른 피로시험 후의 미세 변연 누출 비교)

  • Han, Sun-Deok;Kim, Won;Choi, Ji-Young;Oh, Nam-Sik;Lee, Myung-Hyun
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.3
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    • pp.342-347
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    • 2009
  • Statement of problem: when using resin for class II restoration, micoleakage by instrumentation can be regarded as the primary negative characteristic. A review of the available literature suggests that using flowable resin as liner to decreased microleakage. Purpose: The aim of this study was to determine the influence of the nanofilled flowable resin lining on marginal microleakage after load cycling in class II composite restoration fillings using nanofiller resin. Material and methods: 24 extracted premolars were prepared with class II cavity. F group was restored the nanofilled resin with the nanofilled flowable resin as liner. NF group was restored the nanofilled resin only. After restoration, an experiment was performed on 2 groups using a 300N load at 104, 105 and 106 cycles. Prior to and before each load cycling, it was gauged length on total marginal microleakage, axial marginal microleakage and buccal, gingival, lingual marginal microleakage. Data were analyzed with the Mann-Whitney test & Kruskal-Wallis test. Results: There were statistically significant differences between 2 groups and between individual groups. (P <.05) The result showed less microleakage in teeth restored by the nanofilled resin, which was lined by the nanofilled flowable resin. Conclusion: There was significant reduction in microleakage when the nanofilled flowable resin lining was placed underneath the nanofilled resin in class II composite restoration fillings.

Hygienic process of recycling salting solution of salted chinese cabbage (총설 - 절인배추의 위생적 절임수 재활용 처리기술)

  • Jeong, Jin-Woong;Sung, Jung-Min
    • Bulletin of Food Technology
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    • v.26 no.2
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    • pp.92-100
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    • 2013
  • 배추 절임 공정에서 위해 미생물로부터의 안전성 확보를 위한 위생적 세척 처리기술개발로 효율적인 재활용 시스템을 개발하고자 전기분해수를 활용하여 실험하였다. 전기 분해수의 농도는 100 ppm 으로 염수와 전해수의 비율을 1:9, 2:8, 5:5로 20회 반복 실험을 하였다. 그 결과 기존의 절임수 재활용 횟수인 3~5회를 훨씬 초과하여 10회 이상 반복하여도 총균수가 초기에 비해 2 log CFU/g 이상 감소된 결과를 나타내었다. 또한 재활용 처리된 염수의 pH나 산도 또한 초기에 비해 큰 차이를 보이지 않아 기존의 재활용 방법에 비해 효율적인 결과를 나타내었다. 조사되어진 바에 따르면 절임 공정에서 사용되어진 염수의 회수율은 70~80%에 달했으며, 절임공정에서 본 연구에서와 같이 전해수와 사용된 절임수가 1:9 또는 2:8 비율이 효율적일 것으로 판단된다. 재활용 처리되어진 염수로 절인 배추로 김치를 제조하여 관능평가를 한 결과, 기존의 방법으로 만들어진 김치와 큰 차이를 보이지 않아 본 재활용 시스템 방법은 기존의 시스템의 문제점으로 제기되었던 절인 배추의 성상 변화와 김치의 맛의 변화의 문제점을 해결할 수 있을 것으로 판단된다.

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A Study on High-Repetition Rate Optical-Pulse for Loop-Mirror (루프 미러를 이용한 고 반복률 펄스 발생에 관한 연구)

  • Jeoung Chan-gwoun;Kim Sun-youb;Kang Young-jin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.5
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    • pp.1117-1122
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    • 2005
  • This paper is studied the high-repetition rate optical-pulse stream generation using optical loop mirror coupler. With the recent development of the ultrahigh-speed optical time division multiplexed system, hish-repetition rate optical-pulse stream generation is necessary. This is different from conventional approaches, which use fiber or integrated waveguide delay line circuits. The high-repetition-rate optical-pulse multiplication phenomenon occurs when the optical pulse's spectral width is greater than the transfer bandwidth of the coupler used. From the analysis, the output repetition rate can be controlled by using fiber couplers with different equivalent transfer bandwidths. The pulse separation spacing is controlled by number of cascaded coupler in optical loop mirror coupler scheme.

Repeated Reading Experience of University Students (대학생들의 반복독서 경험에 관한 연구)

  • Lee, Seung-Chae
    • Journal of the Korean Society for Library and Information Science
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    • v.41 no.2
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    • pp.161-180
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    • 2007
  • The goal of this study is to examine what sort of books people read repeatedly, what are the different preferences between men and women, how much the repeatedly-read books are related to the most memorable books and how the repeatedly-read books are connected to reading habits. A questionnaire was provided to college students and their repeated reading experiences were searched. The results of the statistical analysis are summarized : 1) Most college students have experienced repeated reading more than twice. 2) The number of college students who have experienced repeated reading twice is the highest and next, those who have read repeatedly 3 times. Also, the number of times of repeated reading tends to be similar between male and female students. 3) The books which many students read repeatedly more than twice are : a) Romance of 3 Kingdoms b) Little Prince c) Da Vinci Code d) Alchemist e) Chinese nine spine stickle back f) Meu Pe do Larania Lima g) Harry potter. 4) About half of the students have read the most memorable books many times. 5) The importance of books was evaluated on the basis of the number of repeated readers and the number of readings. The order of the important books is Three Romans of 3 kingdoms, Little Prince, Da Vinci Code, Meu Pe do Larania Lima, Tuesdays with Mollie, Harry Potter, and The Myth of Greece and Rome. 6) The preferred books by male college students are mostly the stories of fighters while female likes books that contain deep emotion and morality. More than half of the males' repeated reading was Romance of 3 Kingdoms while the preferred books of females are distributed widely.

Analysis of Interrelationship between Undrained Static and Cyclic Shear Behavior for Nak-Dong River Sand (낙동강 모래의 비배수 정적 및 반복 전단거동 상호관계 분석)

  • Kim, Dae-Man;Kim, Byung-Tak
    • Journal of the Korean Geotechnical Society
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    • v.22 no.10
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    • pp.151-163
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    • 2006
  • This paper presents the interrelationship between undrained static and cyclic shear behavior. Laboratory works were performed through the undralned static and cyclic triaxial test using Nak-Dong River sand. And static triaxial test involved the triaxial extension test for comparison with cyclic shear behavior Cyclic triaxial test was performed with a variety of combination conditions of initial static shear stress $(q_{st})$ and cyclic stress $(q_{cy})$. In this result, the stress path of cyclic shear behavior was correspondent with static shear behavior passing the critical stress ratio (CSR) line because of the development of flow deformation. After that, a failure occurred according to failure line (FL) of static shear behavior. The stress path of cyclic shear behavior showed essentially the same with static shear behavior, although it appears a little different in test method.

Performance Enhancement through Row-Column Cross Scanning in Differential Histogram-based Reversible Watermarking (차이값 히스토그램 기반 가역 워터마킹의 행열 교차 스캐닝을 통한 성능 향상 기법)

  • Yeo, Dong-Gyu;Lee, Hae-Yeoun;Kim, Byeong-Man
    • The KIPS Transactions:PartB
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    • v.18B no.1
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    • pp.1-10
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    • 2011
  • Reversible watermarking inserts watermark into digital media in such a way that visual transparency is preserved, which enables the restoration of the original media from the watermarked one without any loss of media quality. It has various applications, where high capacity and high visual quality are major requirements. This paper presents a new effective multi-round embedding scheme for the differential histogram-based reversible watermarking that satisfies high capacity requirements of the application. The proposed technique exploits the row-column cross scanning to fully utilize the locality of images when multi-round embedding phase to the message inserted image. Through experiments using multiple kinds of test images, we prove that the presented algorithm provides 100% reversibility, effectiveness of multi-round embedding, and higher visual quality, while maintaining the induced-distortion low.

Effects of Castration on Growth and Meat Quality in Finishing Male Jeju Horses (거세가 비육기 제주마의 증체 및 육질에 미치는 영향)

  • Lee, Chong-Eon;Seong, P.N.;Oh, W.Y.;Kim, K.I.
    • Journal of Animal Science and Technology
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    • v.47 no.3
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    • pp.391-396
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    • 2005
  • 이 연구는 거세가 제주 수말 비육시 성장 및 육질에 미치는 영향을 구영하기 위해 수행되었다. 24필(16-20개월령 )의 제주마를 12두씩 대조구(비거세)와 거세구에 3반복 (반복 당 4두)으로 배치하여 380일 동안 비육 시험을 실시하였다. 건초와 물은 자유급식 시켰고, 농후사료는 초기 260일 동안 체중의 1.25%, 후기 120 일 동안은 체중의 1.5% 급여하였다. 일당증체량과 사료섭취량은 처리 간 차이가 없었다. 등심단면적은 거세시 다소 증가되었고(P < 0.05), 근내지방도도 유의적 차이는 없었지만(P=0.08) 거세에 의해서 개선되는 경향을 보 였다{2.10 vs 1.59). 거세에 의해서 말고기 등심의 조지방 힘량은 증가된(P < 0.01) 반면, 수분과 조단백질 함량 은 감소되는 경향을 보였다 등심의 육색, pH, 가열감량 및 보수력은 거세 유무에 따른 차이를 보이지 않았 으나, 전단력은 거세구가 다소 감소하는 경향을 보였다(5.2vs 6.4 kg / 1.0-cm diameter core). 말고기 관능평가 에서는 거세구가 비거세에 비해 다즙성 연도 및 향미에서 개선된 경향을 보였다. 이 연구 결과, 제주마를 거 세 비육함으로써 근내지방도를 증가시켜 말고기의 육질을 개선시킬 수 있을 것으로 사료된다.