• 제목/요약/키워드: Multiple comparisons

검색결과 374건 처리시간 0.035초

출구 버퍼모듈을 갖는 패킷 교환식 상호 연결 망의 성능 분석 (Performance Analysis of Packet Switch Interconnection Networks with Output Buffer Modules)

  • 추현승;박경린
    • 한국정보처리학회논문지
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    • 제6권4호
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    • pp.1045-1057
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    • 1999
  • 패킷교환식 다단계 상호 연결 망은 디지털 교환시스템과 슈퍼 컴퓨터분야에서 널리 이용되어 왔다. 본 논문에서 교환 요소내부의 여러 개의 패킷이 한 네트워크 주기동안 그 주기의 대역폭을 충분히 사용함으로써 다음 단계의 교환 요소로 전송되어 질 수 있음을 보인다. 기존의 상호 연결 망에서는 보통 하나의 패킷 전송을 가정했다. 다중 패킷 전송방식이 도입된 다단계 상호 연결 망의 분석적 모델이 소개되고, 컴퓨터 시뮬레이션에 의하여 그 모델의 타당성을 입증한다. 단일 패킷 전송방식을 이용한 전형적인 다단계 상호 연결 망과의 비교는 실용적인 크기의 연결 망에 대하여 처리율이 약 30% 정도까지 증가함을 보여준다. 비슷한 결과가 지연시간에 있어서도 얻어진다. 네트워크 전송량이 불균등한 분포를 나타내는 경우의 성능 향상은 더욱 중요하다.

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수술실 간호사의 조직사회화와 이직의도 (Organizational Socialization and Intention to Leave in Operating Room Nurses Working at Secondary General University Hospitals)

  • 윤수정;박혜자
    • 간호행정학회지
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    • 제21권1호
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    • pp.88-98
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    • 2015
  • Purpose: To evaluate the relationship between organizational socialization and intention to leave, and to identify factors affecting on intention to leave in operating room nurses. Methods: This study used a descriptive design. Seventy operating room nurses recruited from three hospitals under the same management style, in-service educational system, and working conditions agreed to participate in this study, and completed self-administered questionnaires of the organizational socialization and the intention to leave questionnaire. Respondents were classified by career as advanced beginner, competent practitioner, proficient practitioner and expert practitioner by Benner's stages of nursing proficiency. Data were analyzed with t-test, ANOVA with multiple comparisons, Spearman correlation, and multiple regression analysis. Results: Nurses unsatisfied with the current in-service continuous education had lower organizational socialization and higher intention to leave. In advanced beginners, job performance was lowest and organizational commitment was highest. In expert practitioners, intention to leave was highest. Organizational commitment, interpersonal relationship, identity and burnout were associated with intention to leave. Mutual trust, burnout, and interpersonal relationship were predictors of intention to leave explained 20.8% of variance. Conclusion: The career ladder program to enhance nurses' organizational socialization and intention to stay should be established and expanded for well-experienced operating room nurses.

Identification of weight-control behaviors practiced by diverse groups of college students

  • Lee, Soo-Kyung;Keenan, Debra Palmer;Ryu, Ho-Kyung
    • Nutrition Research and Practice
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    • 제1권3호
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    • pp.218-223
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    • 2007
  • This study investigated: 1) what weight-related behaviors college students practiced; 2) if the behaviors were performed for weight-related reasons; and 3) whether the behavioral practices differed by gender, race, and body weight status. This cross-sectional study used a questionnaire to collect information from a non-probability sample of undergraduate students (n=379; 48% men) recruited from large introductory psychology classes. Chi-square tests were conducted to examine simple comparisons, and multiple logistic regression analyses assessed differences. Male students reported adopting significantly fewer weight-related behaviors than females. Most frequently males increased exercise (69.2%), increased fruit and vegetable consumption (50%), skipped meals (46%), cut out sweets and junk foods (40%), and cut out between-meal snacks (35%). Female students most frequently increased exercise (67.4%), skipped meals (63%), increased fruit and vegetable consumption (62%), reduced the amount of food eaten (60%), and cut out between-meal snacks (51%). Negative behaviors were engaged in by only a few participants. Weight-related reasons were a significant factor for weight-related behavior adoption. Multiple logistic regression analyses showed that gender was consistently and significantly associated with the adoption of weight-related behaviors, while race and weight status were less consistently associated. Findings of this study will be helpful to dietitians who counsel college students. Results of this study may support effects to bring more comprehensive behaviorally-focused health md nutrition interventions to college campuses.

삼차 스플라인 보간법을 활용한 탈퇴율 전환방법 (Conversion between Decrement Models using Cubic Spline)

  • 김주경;이항석
    • 응용통계연구
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    • 제26권3호
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    • pp.549-568
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    • 2013
  • 보험상품의 보험료를 계산하거나 리스크 관리를 하는 과정에서 다중탈퇴율이 필요하지만 경험 자료의 부족으로 절대탈퇴율을 다중탈퇴율로 전환하여 많이 사용한다. 다중탈퇴율과 절대탈퇴율간의 전환에는 소수연령분포를 균등분포로 가정하거나 탈퇴력을 상수로 가정하여 전환하는 방법을 주로 사용한다. 하지만, 이러한 가정하에서는 전환 시 오차가 발생하므로 본 연구에서는 전환오차를 줄이기 위하여 소수연령분포를 삼차 스플라인 함수로 추정하여 전환하는 방법을 제안한다. 기존에 많이 사용하던 방법은 탈퇴력이 불연속적이라는 특징이 있었으나 새로이 제시하는 방법은 탈퇴력이 연속적이라는 측면에서 차이가 있다. 수치 예를 통하여 기존의 방법과 오차를 비교해 봄으로써 스플라인 추정법이 오차를 줄이는데 효과적임을 확인할 수 있다.

Multiple-Method에 의한 원형구조물 변형측정의 정확도 향상에 관한 연구 (A Study on the Improvement of Accuracy for Deformation Measurement of Circular Structures by Multiple Method)

  • Raymond J. Hintz;Mook, Kang-Joon;Jin, Oh-Won
    • 한국측량학회지
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    • 제6권1호
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    • pp.13-24
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    • 1988
  • 원형 구조물의 표면에 대한 삼차원 위치 결정은 여러 면에서 그 응용이 기대된다. 구조물의 진단을 고려해 볼때 이것은 광범위한 범주에서 하나의 의미있는 Topic이 될 것이며, 이러한 위치 결정을 함에 있어 수렴사진의 활용은 종내의 측량에 비해 많은 이점을 가지고 있다. 본 논문은 Metric과 Non-metric Camera를 이용하여 원사형의 피사체를 수렴사진으로 촬영하고 Bundle-Adjustment에 의해 그 결과를 고찰한 것이다. Bundle-Adjustment에 의한 오차 해석으로부터 표준 오차를 비교함과 아울러 Metric과 Nonmetric Camera로부터 얻은 피사체의 삼차원 좌표도 비교하였다.

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요소.포름알데히드 수지가공 셀룰로오스계 직물의 열특성 (The Thermal Characteristics of Cellulose Fabrics Finished with Urea-Formaldehyde Resin)

  • Song, Wha Soon
    • 한국염색가공학회지
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    • 제5권4호
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    • pp.79-91
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    • 1993
  • The purpose of this study is to prepare the newer, more comfortable of urea-formaldehyde resin finished fabrics. The methods of this study are by making examinations and comparisons the relations between the thickness, fabrics counts, weight, moisture regain and crease recovery of cotton and viscose rayon fabrics caused by condition of urea-formaldehyde resin finishing and warm retaining ability and warm-cool sense. The analytic results of thermal character in state of fabrics material finished with urea-formaldehyde are as follows: 1. The warm retaining ability has no correlation with mixing ratio of resin but the increase of the warm retaining ability has correlation with the increase of concentration of urea-formaldehyde resin. 2. The result pf multiple regression analysis for effect of physical property according to the concentration of resin to the warm retaining ability revealed as below. As the weight, thickness and density increase and moisture regain decreases, the warm retaining ability increases. 3. The qmax value has no correlation with mixing ratio of resin but the increase of the qmax value has correlation with the increase of resin concentration. In the end, the effect of it promotes cool sense. 4. The result of multiple regression analysis for effect of physical property according to the concentration of resin to the qmax value revealed as below. As he weight and thickness increase, the qmax value decrease. But, as the density and crease recovery increase, the qmax value increase.

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신호대잡음비가 낮고 부정확한 채널추정값을 가질 때의 CDMA, OFDM, MC-CDMA의 성능 비교 (Peformance Comparisons of CDMA, OFDM, and MC-CDMA with Inaccurate Channel Estimates and Low-SNR Environments)

  • 임민중
    • 한국통신학회논문지
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    • 제30권1A호
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    • pp.55-61
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    • 2005
  • 이동통신 시스템은 좋은 채널환경에서 고속의 데이터 전송이 가능해야 할 뿐만 아니라 이동통신 환경에서 발생할 수 있는 열악한 환경에서도 잘 동작할 수 있어야 한다. 이 논문에서는 신호대잡음비가 낮고 채널추정값이 부정확한 환경에서 CDMA(Code Division Multiple Access), OFDM(Orthogonal Frequency Division Multiplexing), MC-CDMA(Multi-Carrier CDMA)의 성능을 비교 분석하였다. 논문의 수식 및 실험결과에서, 주파수 도약을 사용하는 OFDM 시스템이 l0dB 이상의 성능 감소가 발생하는 열악한 환경에서도 CDMA 시스템의 성능 감소는 크지 않은 것을 보였다. 또한 채널추정값의 신뢰도가 떨어질 때에는 OFDM에서 주파수 도약이나 시간축 확산을 하는 것 보다는 MC-CDMA와 같이 주파수축 확산을 하는 것이 채널 보상 성능에 도움이 된다는 것을 보였다.

Heuristic Algorithms for Constructing Interference-Free and Delay-Constrained Multicast Trees for Wireless Mesh Networks

  • Yang, Wen-Lin;Kao, Chi-Chou;Tung, Cheng-Huang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제5권2호
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    • pp.269-286
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    • 2011
  • In this paper, we study a problem that is concerning how to construct a delay-constrained multicast tree on a wireless mesh network (WMN) such that the number of serviced clients is maximized. In order to support high-quality and concurrent interference-free transmission streams, multiple radios are implemented in each mesh node in the WMNs. Instead of only orthogonal channels used for the multicast in the previous works, both orthogonal and partially overlapping channels are considered in this study. As a result, the number of links successfully allocated channels can be expected to be much larger than that of the approaches in which only orthogonal channels are considered. The number of serviced subscribers is then increased dramatically. Hence, the goal of this study is to find interference-free and delay-constrained multicast trees that can lead to the maximal number of serviced subscribers. This problem is referred as the MRDCM problem. Two heuristics, load-based greedy algorithm and load-based MCM algorithm, are developed for constructing multicast trees. Furthermore, two load-based channel assignment procedures are provided to allocate interference-free channels to the multicast trees. A set of experiments is designed to do performance, delay and efficiency comparisons for the multicast trees generated by all the approximation algorithms proposed in this study.

Streptozotocin 유발 당뇨 흰쥐에서 백삼 에탄올엑스와 IH-901의 항당뇨 작용 비교 (Comparisons of Antidiabetic Activities between White Ginseng Ethanol Extract and IH-901 in Streptozotocin-Induced Diabetic Rats)

  • 고성권;성종환;최용의;이충렬;박경수;정성현
    • 약학회지
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    • 제47권1호
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    • pp.52-55
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    • 2003
  • Antidiabetic activities of white ginseng 50% ethanol extract (WGE) and IH901, an intestinal metabolite of ginsenoside R $b_1$, were compared in multiple low dose streptozotocin (STZ)-induced diabetic rats. WGE or IH901 were coadministered with STZ on Day 1 at dose of 100 and 300 mg or 10 and 30 mg, respectively, and continually administered for 16 days. STZ dissolved in citrate boner was injected intraperitoneally at dose of 20 mg/kg for 5 consecutive days. During the experiment, plasma glucose level and body weight were measured every 4$^{th}$ day. Amount of food and water intake were evaluated once a week and compared between groups. WGE and IH901 both significantly reduced the plasma glucose levels on Day 16 as compared with those of the diabetic control group. In the meantime, amount of food and water intake in WGE-and IH901-treated groups were significantly improved in a dose dependent fashion as compared with those of the diabetic control group. Taken together WGE and IH901 showed the comparable antidiabetic activities at the corresponding doses used in this experiment.

Multi-factor Evolution for Large-scale Multi-objective Cloud Task Scheduling

  • Tianhao Zhao;Linjie Wu;Di Wu;Jianwei Li;Zhihua Cui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제17권4호
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    • pp.1100-1122
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    • 2023
  • Scheduling user-submitted cloud tasks to the appropriate virtual machine (VM) in cloud computing is critical for cloud providers. However, as the demand for cloud resources from user tasks continues to grow, current evolutionary algorithms (EAs) cannot satisfy the optimal solution of large-scale cloud task scheduling problems. In this paper, we first construct a large- scale multi-objective cloud task problem considering the time and cost functions. Second, a multi-objective optimization algorithm based on multi-factor optimization (MFO) is proposed to solve the established problem. This algorithm solves by decomposing the large-scale optimization problem into multiple optimization subproblems. This reduces the computational burden of the algorithm. Later, the introduction of the MFO strategy provides the algorithm with a parallel evolutionary paradigm for multiple subpopulations of implicit knowledge transfer. Finally, simulation experiments and comparisons are performed on a large-scale task scheduling test set on the CloudSim platform. Experimental results show that our algorithm can obtain the best scheduling solution while maintaining good results of the objective function compared with other optimization algorithms.