• 제목/요약/키워드: internal stability

검색결과 1,114건 처리시간 0.028초

GND조건이 CISPR25 복사방출 시험에 미치는 영향에 관한 연구 (A Study on the Effect of GND Condition on CISPR25 Radiation Emission Test)

  • 윤진상;홍익표
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2018년도 춘계학술대회
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    • pp.404-407
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    • 2018
  • 1장 - 자동차는 엔진에서 만든 동력을 바퀴에 전달하여 지상에서 승객이나 화물을 운반하는 교통 수단이다. 과거에 내연기관에서에서 출발한 자동차는 최근에는 전기자동차와 혼합된 하이브리드와 순수 전기자동차 등이 출시되고 있다. 이로 인한 다양한 부품으로 인한 기술의 발전 및 안정성 강화 등으로 첨단 전기 전자제품의 배치는 증가할 수 밖에 없었고 그로 인해 전자파 환경은 더욱 복잡하고 다양할 수 밖에 없다. CISPR 25에서는 전자기파 노이즈에 대한 시험 방법에 대해서 연구를 진행 중에 있다. 그 중 복사방출 시험에서 요구된 GND 조건에 따른 노이즈 패턴을 분석 하기 위해 다양한 조건을 적용해 비교 검증하고자 한다. 2장 - EMI 챔버의 일반적인 특성 기술, 시험 법 및 측정 장비에 대해 기술한다. 3장 - RE 시험 : 시료가 Center에 있을 때 Ground Strap 변화에 따른 노이즈 분석, 시료가 Center가 아닌 다른 곳에 있을 때 Ground Strap 변화에 따른 노이즈 분석 검증 하고자 한다.

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Development of a CAN-based Real-time Simulator for Car Body Control

  • Kang, Ki-Ho;Seong, Sang-Man
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.444-448
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    • 2005
  • This paper presents a developing procedure of the CAN-based real-time simulator for car body control, aiming at replacing the actual W/H (Wiring Harness) and J/B(Junction Box) couple eventually. The CAN protocol, as one kind of field-bus communication, defines the lowest 2 layers of the ISO/OSI standard, namely, the physical layer(PL) and the data link layer(DLL), for which the CSMA/NBA protocol is generally adopted. For CPU, two PIC18Fxx8x's are used because of their built-in integration of CAN controller, large internal FLASH memory (48K or 64K), and their costs. To control J/B's and actuators, 2 controller boards are separately implemented, between which CAN lines communicate through CAN transceivers MCP255. A power motor for washing windshield, 1 door lock motor, and 6 blink lamps are chosen for actuators of the simulator for the first stage. For the software architecture, a polling method is used for the fast global response time despite its slow individual response time. To improve the individual response time and to escape from some eventual trapped-function loops, High/Low ports of the CPU are simply used, which increases the stability of the actuator modules. The experimental test shows generally satisfactory results in normal transmitting / receiving function and message trace function. This simulator based on CAN shows a promising usefulness of lighter, more reliable and intelligent distributed body control approach than the conventional W/H and J/B couple. Another advantage of this approach lies in the distributed control itself, which gives better performance in hard real-time computing than centralized one, and in the ability of integrating different modules through CAN.

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Reliability and Validity of the Malay Version of the Breast-Impact of Treatment Scale (MVBITS) in Breast Cancer Women undergoing Chemotherapy

  • Zainal, Nor Zuraida;Shuib, Norley;Bustam, Anita Zarina;Sabki, Zuraida Ahmad;Guan, Ng Chong
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권1호
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    • pp.463-468
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    • 2013
  • Background: Body image dissatisfaction among breast cancer survivors has been associated with psychological stress resultant from breast cancer and resultant surgery. This study aimed to examine the psychometric properties of the Malay Version of the Breast-Impact of Treatment Scale (MVBITS) and to investigate the associations of retained factors with the Hospital Anxiety and Depression Scale (HADS) and the Rosenberg Self-Esteem Scale (RSES). Materials and Methods: The MVBITS was 'forward-backward' translated from English to Malay and then administered to 70 female breast cancer patients who came to the Oncology Clinic of University Malaya Medical Centre, Kuala Lumpur, Malaysia to undergo chemotherapy. Principal component analysis (PCA) with varimax rotation was performed to explore the factor structure of the MVBITS. Associations of retained factors were estimated with reference to Spearman correlation coefficients. Results: The internal consistency reliability of MVBITS was good (Cronbach's alpha 0.945) and showed temporal stability over a 3-week period. Principal component analysis suggested two factors termed as 'Intrusion' and 'Avoidance' domains. These factors explained 70.3% of the variance. Factor 1 comprised the effects of breast cancer treatment on the emotion and thought, while Factor 2 informed attempts to limit exposure of the body to self or others. The Factor 1 of MVBITS was positively correlated with total, depression and anxiety sub-scores of HADS. Factor 2 was positively correlated with total and anxiety sub-scores of HADS. MVBITS was also positively correlated with the RSES scores. Conclusions: The results showed that the Malay Version of Breast-Impact of Treatment Scale possesses satisfactory psychometric properties suggesting that this instrument is appropriate for assessment of body change stress among female breast cancer patients in Malaysia.

A Study of mechanical properties of oxide layer removed Co-Cr-Mo abutments

  • Ryu, Jae-ho;Huh, Jung-Bo;Ro, Jung-Hoon;Yun, Mi-Jung;Jeong, Chang-Mo
    • 대한치과의사협회지
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    • 제53권11호
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    • pp.804-816
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    • 2015
  • PURPOSE: The aim of this study was to evaluate the influence of the oxide layer removal process in the Co-Cr-Mo (CCM) abutment after casting procedure on the prosthesis settlement and screw stability. MATERIALS AND METHODS: CCM abutments of four different interface conditions (CCM-M; machined, CCM-O; oxide layer formed, CCM-B; blasted, CCM-P; polished after blasted) and gold abutment (Gold-C; Cast with type III Gold alloy) were used. The initial settling values of abutments were evaluated according to the difference of implant-abutment length when the tightening torques were applied at 5 Ncm and 30 Ncm, and the settling values of abutments caused by loading were evaluated according to the difference of implant-abutment length before and after loading with 250 N, 100000 cycle. The loss ratios of removal torque for abutment screws were evaluated according to the difference in value of removal torques under 30 Ncm tightening torque applied before and after cyclic loading. RESULTS: The CCM-P and CCM-B group showed a higher initial settling value compared with the Gold-C group (P<.05), while the Gold-C group showed the highest settling values caused by loading (P<.05) and no significant differences were observed for between CCM groups (P>.05). The loss ratio of removal torque values for the CCM-B, CCM-P groups did not differ significantly from that of the Gold-C group (P>.05). CONCLUSION: Even though the oxide layer was removed by different methods, CCM abutment with internal conical connection structure showed lower abutment settling and similar screw loosening after cyclic loading compared with gold abutment.

상관관계를 반영한 신용등급 계량화 검정기법 연구 (Study on the validation methods of calibration considering correlations)

  • 김은나;하정철
    • Journal of the Korean Data and Information Science Society
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    • 제21권3호
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    • pp.407-417
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    • 2010
  • 신BIS협약에서는 자본적정성 규제에 있어서 자율성 확대를 위해 내부등급시스템을 허용하였고, 이에 따라 시스템의 적합성 검증의 중요성을 더욱 강조하게 되었다. 적합성검증은 양적 질적 검증으로 나뉘며 이 때 양적 검증은 변별력, 안정성, 등급의 계량화로 구별된다. 본 논문에서는 양적 검증의 등급의 계량화 중 신용등급 변화 검정기법에 대하여 연구하려고 한다. 등급의 계량화 검정은 등급별로 추정된 부도율과 실제 부도율과의 차이를 검정하는 방법으로 한 시점에 대한 검정으로 이항검정과 카이제곱검정, Brier score, 신호등 검정이 있고, 여러 시점의 정확성을 검증하는 방법으로 정규성 검정, 확장된 신호등 검정이 있다. 신용평가시스템의 정확성을 높이고, 현실 상황에 반영이 가능하려면 상관관계를 고려하지 않을 수 없다. 본 논문에서는 부도상관관계를 고려한 확장된 신호등 검정을 제안하고자 한다.

옆으로 누운 자세에서 고관절 외전시 반대 측 고관절 내전이 요추안정화 근육 두께와 골반 외측 경사에 미치는 영향 (Effect of Contralateral Hip Adduction on Muscle Thicknesses of Lumbar Stabilizers and Pelvic Lateral Tilting During Hip Abduction in Side-lying)

  • 김효언;최보람;김수정;이원휘;권오윤
    • 한국전문물리치료학회지
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    • 제19권1호
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    • pp.19-27
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    • 2012
  • The purpose of this study was to determine the effect of contralateral hip adduction (CHA) on thickness of lumbar stabilizers during hip abduction in side-lying. Twenty healthy subjects without back pain were recruited for this study. The thickness of transverse abdominis (TrA), internal oblique (IO) and quadratus lumborum (QL) were measured by ultrasonography. Pelvic lateral tilting motion was measured using a three-dimensional motion analysis system. Measurements were performed at rest position (RP), $35^{\circ}$preferred hip abduction (PHA) and $35^{\circ}$abduction with $10^{\circ}$contralateral hip adduction (CHA) in side-lying at the end of expiration. During the measurements, subjects were asked to maintain steady trunk alignment without hand support. Thickness of TrA and IO was significantly greater in CHA than in PHA and RP conditions. There was no significant difference in thickness of TrA and IO between PHA and RP conditions. Medio-lateral (M-L) thickness of QL was not significant between PHA and CHA conditions. Anterio-posterior (A-P) thickness of QL in PHA and CHA significantly decreased compared to RP condition. Angle of pelvic lateral tilting was significantly decreased in CHA compared to PHA condition. In conclusion, CHA can be recommended for increasing trunk stability without compensatory pelvic motion during hip abduction exercise in side-lying.

척추 안정화 운동 방법들에 따른 배근육의 근 활성도 비교 (EMG Activity of Abdominal Muscles During Lumbopelvic Stabilization Exercises)

  • 이규완;윤태림;김기송;이지현;이충휘
    • 한국전문물리치료학회지
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    • 제21권2호
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    • pp.1-7
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    • 2014
  • Lumbopelvic stabilization exercise has become the most popular treatment method in lumbar rehabilitation since its effectiveness was shown in some aspects of pain and disability. The abdominal drawing-in maneuver (ADIM) has been extensively implemented to promote lumbopelvic stability. However, performing ADIM correctly is difficult even for healthy subjects, and it is time consuming to train people in ADIM. Thus, the purpose of this study was to compare abdominal muscle [rectus abdominalis (RA), external oblique (EO), and transverse abdominis/internal oblique (TrA/IO)] activity during lumbopelvic stabilization exercises (ADIM only, ADIM with a ball, maximum exhalation only, and maximum exhalation with a ball) performed in a supine position with feet against a wall. Fifteen healthy subjects were recruited for this study. Surface electromyography was used to measure abdominal muscle activity during lumbopelvic stabilization exercises. A one-way repeated-measures analysis of variance was used to determine the statistical significance of RA, EO, and TrA/IO muscle activity during four lumbopelvic stabilization exercises. Both-side TrA/IO muscle activity was significantly greater with maximum exhalation with a ball than with ADIM only or ADIM with a ball (p<.008). The results of this study suggest that maximum exhalation with a ball can be used as an effective lumbopelvic stabilization exercise to increase TrA/IO muscle activity in healthy subjects.

연직변환좌표(鉛直變換座標)에서 3차원(次元) 유동(流動) 수직모형(數値模型) (A Three-Dimensional Numerical Model of Hydrodynamic Flow on σ-Coordinate)

  • 정태성;이길성
    • 대한토목학회논문집
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    • 제14권5호
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    • pp.1145-1158
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    • 1994
  • 물의 유동(流動)에 관한 계산상 효율성(效率性)을 갖는 자유수면(自由水面)을 고려한 3차원(次元) 유한차분(有限差分) 수직모형(數値模型)을 개발하였다. 수직모형(數値模型)은 연직방향(鉛直方向)에 대해 정규화(正規化)한 좌표(座標)(${\sigma}$-coordinate)를 사용하며, 시간(時間) 적분방법(積分方法)으로는 반음해법(半陰解法)(semi-implicit)을 사용하여 계산시간(計算時間)의 효율성(效率性)을 도모하였다. 모드분리(mode-splitting)개념을 도입하여 내부모드(internal mode)에 대해서는 양해법(陽解法)을 사용하였으며, 외부모드(external mode)는 수평방향(水平方向) 운동량방정식(運動量方程式)들과 연속방정식(連續方程式)의 차분식(差分式)으로부터 구한 타원형(楕圓型) 차분방정식(差分方程式)을 SOR방법에 의하여 해석하였다. 이와 같은 방법은 계산(計算) 시간간격(詩間間隔)이 표면(表面) 중력파(重力波)에 대한 CFL(Courant-Fredrich-Lewy)조건에 의해 제약을 받지 않아 계산시간(計算時間)의 효율성을 도모할 수 있다. 개발된 모형은 1차원(次元) 수로(水路)에서 취송유(吹送流)의 연직분포(鉛直分布)에 대한 해석해(解析解)와 비교(比較) 및 연직(鉛直) 가변격자(可變格子)의 도입에 따른 오차분석(誤差分析) 정사각형(正四角形) 호수(湖水)에서 취송유(吹送流) 계산(計算) 및 차분화(差分化) 상수(常數)들의 민감도(敏感度) 분석(分析)을 수행하였다.

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대학도서관 조직문화에 관한 연구 (A Study on the Organizational Culture of University Libraries)

  • 윤혜영
    • 한국문헌정보학회지
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    • 제34권4호
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    • pp.97-121
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    • 2000
  • 본 연구는 대학도서관 조직문화를 이해하고 실제적인 관리전략으로 활용할 수 있도록 하기 위해 한국의 대학도서관을 대상으로 전체 대학도서관 조직문화를 파악하고 특성에 따른 조직문화의 차이를 비교분석하고자 하는 연구이다. 대학도서관에 근무하는 직원을 대상으로 이들이 인식하는 조직문화의 연구결과 대학도서관 조직문화는 다른 문화유형과 비교해서 위계질서문화에서 지나치게 높은 평균값을 가지고 있었으며 두 번째는 인간관계문화가 우세하였으며, 생산중심문화와 개방체계문화에서는 약한 가치를 가지고 있었다. 앞으로 한국의 대학도서관 조직문화를 연구하는 방법으로 양적 방법뿐 아니라 질적 방법도 고려되어야 할 것이며, 대학도서관 조직문화에 대한 정확한 이해는 신규직원의 선발, 부서 배치 혹은 직무순환시 근거자료로 활용할 수 있을 것이며, 아울러 환경의 변화에 적합한 전략을 계획할 수 있게 됨으로써 조직관리에 효율성을 가져올 수 있을 것이다.

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Development and Psychometric Evaluation of the Patient Safety Violation Scale in Medical Oncology Units in Iran

  • Shali, Mahboobeh;Ghaffari, Fatemeh;Joolaee, Soodabeh;Ebadi, Abbas
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권9호
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    • pp.4341-4347
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    • 2016
  • Background: Patient safety is one of the key components of nursing care for cancer cases. Valid and reliable context-based instruments are necessary for accurate evaluation of patient safety in oncology units. The aim of the present study was to develop and evaluate the psychometric properties of the Patient Safety Violation Scale in medical oncology units in Iran. Materials and Methods: In this methodological study, a pool of 58 items was generated through reviewing the existing literature. The validity of the 58-item scale was assessed through calculating impact score, content validity ratio, and content validity index for its items as well as conducting exploratory factor analysis. The reliability of the scale was evaluated by assessing its internal consistency and testretest stability. Study sample consisted of 300 oncology nurses who were recruited from thirteen teaching hospitals affiliated to Tehran University of Medical Sciences, Tehran, Iran. Results: Sixteen items were excluded from the scale due to having low impact scores, content validity ratios, or content validity indices. In exploratory factor analysis, the remaining 42 items were loaded on five factors including patient fall, verification of patientidentity, harm during care delivery, delay in care delivery, and medication errors. These five factors explained 62% of the total variance. The Cronbach's alpha of the scale and the test-retest interclass correlation coefficient were equal to 0.933 and 0.92, respectively. Conclusions: The 42-item Patient Safety Violation Scale is a simple and short scale which has acceptable validity and reliability. Consequently, it can be used for assessing patient safety in clinical settings such as medical oncology units and for research projects.