• ETRI Journal
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• 제39권1호
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• pp.124-134
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• 2017

Data races are one of the most difficult types of bugs in concurrent multithreaded systems. It requires significant time and cost to accurately detect bugs in complex large-scale programs. Although many race detection techniques have been proposed by various researchers, none of them are effective in all aspects. In this paper, we compare the performance of five recent dynamic race detection techniques: FastTrack, Acculock, Multilock-HB, SimpleLock+, and causally precedes (CP) detection. We experimentally demonstrate the strengths and weaknesses of these dynamic race detection techniques in terms of their detection capability, running time, and runtime overhead using 20 benchmark programs with different characteristics. The comparison results show that the detection capability of CP detection does not differ from that of FastTrack, and that SimpleLock+ generates the lowest overhead among the hybrid detection techniques (Acculock, SimpleLock+, and Multilock-HB) for all benchmark programs. SimpleLock+ is 1.2 times slower than FastTrack on average, but misses one true data race reported from Mutilock-HB on the large-scale benchmark programs.

• 한국운동역학회지
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• 제31권3호
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• pp.162-167
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• 2021

Objective: This study aimed to identify the different wind speed categories and competitive level among windsurfers through GPS variables to provide the useful information on the development of training programs for enhancing windsurfers' performance. Method: Data from 69 female athletes who participated in 27 races during the 2018-2019 windsurfing season were used for the analysis. Average board speed, total race time, total distance, upwind race time, downwind race time, beam reach race time were collected through GPS. Unconfirmed data were excluded along with penalty point data. The wind conditions were classified as light, light to medium, medium, medium to heavy, and heavy wind, the competitive levels were classified as level 1, level 2, and level 3. Results: As for the average board speed, the level 1 or level 2 group showed higher board speed than the level 3 group in all wind conditions except for the light wind. The total race time and upwind race time showed less time in level 1 or level 2 group than level 3 group in all wind conditions. The total distance, downwind race time and beam reach race time showed less distance and time in level1 group than level 3 group under sufficient wind conditions. Conclusion: Our results show that the aerobic capacity to sustain pumping during upwind course in wind conditions below 15 kts effects performance. In wind conditions of 15 kts or more, indicated that the board control for the fast board speed and small distance required during up, down, beam reach courses had an effect on competition performance. This information can be provided to windsurfers and coaching as basic data for training programs to improve performance.

• 한국컴퓨터정보학회논문지
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• 제22권11호
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• pp.1-7
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• 2017

In this paper, we introduce three monitoring filtering techniques which reduce the overheads of dynamic data race detection. It is well known that detecting data races dynamically in multi-threaded programs is quite hard and troublesome task, because the dynamic detection techniques need to monitor all execution of a multi-threaded program and to analyse every conflicting memory and thread operations in the program. Thus, the main drawback of the dynamic analysis for detecting data races is the heavy additional time and space overheads for running the program. For the practicality, we also empirically compare the efficiency of three monitoring filtering techniques. The results using OpenMP benchmarks show that the filtering techniques are practical for dynamic data race detection, since they reduce the average runtime overhead to under 10% of that of the pure detection.

• 한국기계가공학회지
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• 제10권6호
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• pp.46-49
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• 2011

The grinding is a popular process for studying constant velocity joint and process in automobile industry. In this study, The study gives the data of wheel type and grinding of inner race is developed. As a result I obtained the data of grinding conditions makes good surface roughness get a grinding conditions. The grinding characteristics and conditions of inner race were investigated with respect to grinding feed, cutting depth, grinding time. The results were suddenly increased and the detailed surfaces were extremely obtained. Grinding condition was big more affected by grinding time, grinding speed and grinding depth.

• 한국심리학회지:법
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• 제11권1호
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• pp.37-61
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• 2020

Lee, Khogali, Despodova, 와 Penrod의 연구(2019)에서는 관찰자가 피고인과 피해자의 인종과 다른 경우, 타인종 범죄(예: 백인 관찰자, 흑인 피고인, 히스패닉 피해자)보다 동인종 범죄(예: 백인 관찰자, 흑인 피고인, 흑인 피해자)에서 더 가혹한 판결이 내려지는 것을 밝혀내었다. Lee 등의 연구(2019)는 미국 피험자들을 대상으로 실시되었다는 점을 고려하여, 본 연구는 그러한 인종조합효과가 한국 피험자에게서도 나타나는지를 검증하였다. 연구1a는 한국에서 3개의 조절 변인(증거 강도, 피고인의 폭력사용 정도, 인종 특출성)과 함께 인종조합효과를 살펴보았으나, 그 효과의 재현에 실패하였다. 연구1b는 연구1a의 재현실패가 한국과 미국의 문화 차이 때문인지를 검증하기 위하여, 연구 1a와 동일한 실험설계를 사용하여 미국에서 시행되었다. 그러나 연구 1b 역시 인종조합효과를 재현하는 데 실패하였다. 연구2는 연구1a와 연구1b의 데이터와 함께 Lee 등(2019)의 데이터도 통합하여 메타분석적 검토를 시행하였다. 그 결과, 연구1a와 연구1b의 인종 특출성 조작이 그 재현실패의 원인일 수도 있음을 보여주었다. 따라서 본 연구는 피고인과 피해자의 인종과 다른 사람들은 타인종 범죄보다 동인종 범죄에서 더 가혹한 판결을 내리지만, 이러한 인종조합효과는 그 범죄사건에서 인종 관련 사안이 특출해지지 않을 때만 나타나는 것으로 결론지었다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2567-2570
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• 2013

Background: This study analyzed Surveillance, Epidemiology and End Results (SEER) data to assess if socio-economic factors (SEFs) impact on endometrial cancer survival. Materials and Methods: Endometrial cancer patients treated from 2004-2007 were included in this study. SEER cause specific survival (CSS) data were used as end points. The areas under the receiver operating characteristic (ROC) curve were computed for predictors. Time to event data were analyzed with Kaplan-Meier method. Univariate and multivariate analyses were used to identify independent risk factors. Results: This study included 64,710 patients. The mean follow up time (S.D.) was 28.2 (20.8) months. SEER staging (ROC area of 0.81) was the best pretreatment predictor of CSS. Histology, grade, race/ethnicity and county level family income were also significant pretreatment predictors. African American race and low income neighborhoods decreased the CSS by 20% and 3% respectively at 5 years. Conclusions: This study has found significant endometrial survival disparities due to SEFs. Future studies should focus on eliminating socio-economic barriers to good outcomes.

• 한국임상수의학회지
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• 제40권6호
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• pp.464-467
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• 2023

The autonomic regulation of heart rate (HR) is an indicator of the body's ability to adapt to an exercise stimulus. However, there are no reports on this topic in relation to Jeju horses used for racing. The aim of this study was to analyze the HR responses of Jeju horses during race trials and to investigate the correlation between HR and performance in these horses. HR data were collected from 17 healthy 2- to 7-year-old Jeju horses wearing HR monitors during race trials. Pearson correlation coefficients was used to determine the significance of the association between the race trial time and HR. A significant inverse correlation was observed between the race trial time (performance) and both the maximal HR (HRmax, r = -0.69, p < 0.01) and HR reserve (HRR) (HRmax - average HR during the warm-up period, r = -0.63, p < 0.01) and between the HRR and HRmax (r = 0.73, p < 0.01). Horses with a lower average HR during the warm-up period and higher heart rates during the trial achieved faster race trial times. This study reports the first HR measurements in Jeju horses during race trials, providing new insights into the HR response of this breed to exercise. The use of a noninvasive remote HR monitor system allowed assessment of exercise responses in the field, and the results suggest that both the HRR during warm-up period and HRmax may be useful performance indicators in Jeju horses.

• 한국조사연구학회:학술대회논문집
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• 한국조사연구학회 2001년도 춘계학술대회
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• pp.27-59
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• 2001

10년마다 수행되는 미국 인구총조사에서 얻어진 인구통계는 미 하원의석의 주별 할당과 연방예산의 교부에 이용된다. 본 논문의 주목적은 2000년 인구총조사와 관련된 다양한 쟁점들을 살펴보는 것이다. 특히 본 논문은 인구총조사에 있어서 인종과 종족에 따른 순누락률의 차이가 갖는 사회정치적 의미를 분석한다. 또한 우리는 통계자료의 오차를 수정보완하기 위한 표본추출 방법의 사용과 인구총조사 설문지 문항을 둘러싼 인종 종족간의 정치적 쟁점을 살펴보고 있다.

• 한국조사연구학회지:조사연구
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• 제2권2호
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• pp.27-59
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• 2001

10년마다 수행되는 미국 인구총조사에서 얻어진 인구통계는 미 하원의석의 주별 할당과 연방예산의 교부에 이용된다. 본 논문의 주목적은 2000년 인구총조사와 관련된 다양한 쟁점들을 살펴보는 것이다. 특히, 본 논문은 인구총조사에 있어서 인종과 종족에 따른 순누락률의 차이가 갖는 사회정치적 의미를 분석한다. 또한, 우리는 통계자료의 오차를 수정보완하기 위한 표본추출 방법의 사용과 인구총조사 설문지 문항을 둘러싼 인종 종족간의 정치적 쟁점을 살펴보고 있다.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2019년도 제59차 동계학술대회논문집 27권1호
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• pp.7-8
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• 2019

자료경합은 두 개 이상의 스레드가 같은 공유메모리에 적절한 동기화 없이 접근하고, 적어도 한 개의 접근사건이 쓰기일 때 발생할 수 있는 동시성 오류이다. 자료경합은 프로그래머가 의도하지 않은 비결정적인 수행결과를 초래하여, 항공기 소프트웨어와 같은 고신뢰성이 요구되는 프로그램에서 치명적인 오류를 발생시켜 인적 물적 손해로 이어질 수 있다. 자료경합 탐지기법은 이러한 문제를 사전에 탐지하여 수정하는데 사용되어진다. 하지만 GPGPU 프로그램에서의 자료경합은 CPU 병행프로그램에서보다 복잡한 실행구조를 가지고 있어 스레드 및 메모리 계층, 스케줄링, 동기화 기법 등의 많은 변수가 존재한다. 이로 인해 실세계 프로그램에 자료경합 탐지기법을 적용하여 검증 시 이러한 변수들을 반영하여 실험하는데 많은 노력이 소요된다. 본 논문은 실세계 프로그램에서의 자료경합을 대표하는 4가지 패턴의 합성프로그램으로 이루어지고 실행 시 스레드 및 메모리 계층, 스레드 구조, 메모리 사용량 및 동기화 방안을 지정할 수 있는 벤치마크 모음을 제시한다.