• 제목/요약/키워드: time effect

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시간의존성 균열 패턴을 고려한 탄산화에 노출된 콘크리트의 확률론적 내구수명 평가 (Service Life Evaluation of RC Column Exposed to Carbonation Considering Time-dependent Crack Pattern)

  • 권성준
    • 한국건설순환자원학회논문집
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    • 제4권1호
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    • pp.10-18
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    • 2016
  • 대도시의 콘크리트 구조물은 탄산화에 노출되며 사용기간의 증가로 인해 내구성 저하를 나타내며 콘크리트에 발생하는 균열은 국부적인 탄산화 증가를 야기한다. 본 연구에서는 실태조사를 통하여 균열부의 탄산화속도를 분석하였으며, 이를 시간의존성균열과 초기재령균열로 구분하여 탄산화에 노출된 RC교각의 내구수명을 분석하였다. 실태조사 결과를 기본으로 균열이 최대 0.3mm까지 진전하고 여기에 최대 균열폭에 이르는 시간을 변수로 하여 내구성 파괴확률, 신뢰성 지수, 내구수명 등이 평가되었다. 시간의존성균열 패턴은 초기재령부터 발생한 균열보다 낮은 내구성파괴확률과 높은 내구수명을 나타내었는데, 이는 지나치게 보수적인 해석기법보다 합리적이다. 또한 피복두께가 100mm보다 클 경우, 균열에 대한 시간효과는 내구성 파괴확률 및 내구수명에 큰 영향을 미치지 못하였다. 고정 균열이 아닌 시간의존적균열을 고려한 확률론적 내구수명 해석기법은 운용 중 발생하여 균열이 발생한 구조물에 효과적으로 사용될 것이다.

계혈등(鷄血藤)의 Beta-sitosterol 성분이 자궁근종세포의 증식억제와 세포자멸사의 유도에 미치는 영향 (The effect of β-sitosterol proliferation and apoptosis in human uterine leiomyoma cells)

  • 박영선;백승희
    • 대한한방부인과학회지
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    • 제18권1호
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    • pp.181-191
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    • 2005
  • Purpose : ${\beta}$-sitosterol is kind of phytosterols or plant which are structurally similar to cholesterol. This study was aimed to investigate the inhibitory effect of the ${\beta}$-sitosterol on the proliferation of human uterine leiomyoma cells and the expression of gene related the mechanism of cell apoptosis. Methods : We counted the number of death cells treated with indicated time of the ${\beta}$-sitosterol and investigated cell death rate by cell count assay. Furthermore, flow cytometry analysis and DNA fragmentation assay were used to dissect between necrosis and apoptosis. and then we observed the differential gene expression by western blot analysis. Results : 1) The inhibitory effect on the growth of uterine leiomyoma cell treated with the ${\beta}$-sitosterol $16{\mu}M$ was increased in a time dependent. 2) The result of flow cytometry analysis, subG1 phase arrest related cell apoptosis was investigated 16.97% in uterine leiomyoma cell treated with the ${\beta}$-sitosterol $16{\mu}M$ and showed the fashion of proportional time dependent. 3) The gene expression of p27, p21 related cell cycle was increased according to increasing time interval but cyclin E-CDK2 complex was decreased expression. 4) The character of apoptosis, DNA fragmentation was significantly observed on the time dependent. 5) The expression of pro-caspase 3 and PARP were decreased dependent on treatment with time dependent. Conclusion : This study showed that the ${\beta}$-sitosterol have the inhibitory effect on the proliferation of human uterine leiomyoma cell and the effect was related with apoptosis.

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레스토랑의 대기 장소의 위치가 고객의 대기시간 지각에 미치는 영향 (The Effect of Location of Waiting Place on Consumers' Perceived Waiting Time in a Family Restaurant)

  • 박은영
    • 유통과학연구
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    • 제17권6호
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    • pp.77-84
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    • 2019
  • Purpose - Although an extensive body of research in psychology and marketing focuses on perceived waiting time, no research has examined the effect of the location of the waiting place on perceived waiting time. In particular, this study suggests that customers who are waiting in a restaurant may have different perceived waiting time depending on whether they are in close proximity to the service area (e.g., dining area) or farther from it. In particular, the author examines how and why the location of the waiting place affects the perceived waiting time of the consumer and reveals the mental simulation as its psychological mechanism. Research design, data, and methodology - This study conducted field surveys with customers waiting in real restaurants. Eighty-eight people participated under two conditions: a restaurant with a waiting place near the dining area and a restaurant with a waiting place far from the dining area. Participants responded to questions about perceived waiting time (the dependent variable), mental simulation (the mediator), and demographic variables. To verify the hypothesis, ANOVA and bootstrapping analysis were performed. Results - The major results from the field study are as follows. First, participants perceived wait time differently depending on the location of the restaurant's waiting place: participants in the restaurant with a waiting place close to the dining area perceived significantly shorter waiting times. Second, the effect of the location of the waiting place on the perceived waiting time was mediated by mental simulation: the closer the wait location is to the dining area, the more imagination the customer exercises about the meal, which in turn distracts attention from time flow and shortens the perceived wait time. Conclusion - This study has a theoretical implication in that it extends research on perceived waiting time as the first study of how and why the location of a waiting place affects a customer's perceived waiting time. It has a practical implication that can be used as a marketing tactics to improve the image of the service provider by changing the location of the waiting place.

유침(留鍼)시간에 대한 문헌적 고찰: 중국 문헌을 중심으로 (A Literary Review on Needle Retaining Time: Centered on the Chinese Medical Journal)

  • 왕개하;이은솔;조현석;김경호
    • Journal of Acupuncture Research
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    • 제28권5호
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    • pp.65-76
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    • 2011
  • Objectives : Study about needle retaining time. Methods : We reviewed the ancient and the present text of China with using the China academic journal(CAJ) of China national knowledge infrastructure(CNKI) Results & Conclusions : 1. Needle retaining time is important in acupuncture, because the therapy effect is influenced by it. 2. The time of needle retaining is up to those conditions like different disease, viscera and bowels(臟腑), meridian and collateral(經絡), obtaining Qi(得氣), seasons, constitution of the patients and acupuncture tools. In ${\ll}$Hwangdineijing(黃帝內經) ${\gg}$, needle retaining time is called by 'Zhiruzhichu(直入直出)', 'Jichu(疾出)', 'Liu(留)', 'Buliu(不留)', 'Jiuliu(久留)' and 'Liu ${\bigcirc}$ hu(留${\bigcirc}$呼)', and the time was shorter than nowadays. 3. The respiration number was counted to check needle retaining time but we can't find out any evidence. Recently in China, 'obtaining Qi(得氣)' and 'Qi arrival(氣至)' is used to check it. 4. Looking into clinical researches, different diseases need different needle retaining time. For example, 20~30min is appropriate time for musculoskeletal system. 60min is for circulatory system, 10~20min is for peripheral facial nerve paralysis. Insomnia and some stubborn diseases need longer time. Cold and heat(寒熱), deficiency and excess(虛實) are always influences the needle retaining as well. 5. It is important to figure out the most effective needle retaining time for different disease with the base of connection between needle retaining time and effect.

항공사 서비스 과정의 대기환경이 지각된 대기시간 및 서비스 결과품질에 미치는 영향에 관한 연구 (The Effect of Waiting Environment of Airline Service on Perceived Waiting Time and Service Quality)

  • 이지영;한희은;최성우
    • 한국콘텐츠학회논문지
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    • 제16권3호
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    • pp.575-585
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    • 2016
  • 본 연구는 항공사의 서비스과정 중 발생하는 대기를 항공기 탑승 전, 후로 나누어 물리적 환경과 인적 환경이 지각된 대기시간 및 항공사의 서비스품질에 미치는 영향에 대해 다룬다. 여러 항공서비스를 이용한 승객을 대상으로 300부를 배포한 뒤 유의한 총 231개의 설문지를 통해 분석 한 결과 서비스 과정 중의 대기 환경은 지각된 대기시간과 서비스품질에 유의한 영향을 미치며, 특히, 항공기 탑승 전(기내 서비스 전)에는 물리적 환경이, 항공기 탑승 후(기내 서비스 중)에는 인적환경이 더 영향을 미친다는 결과가 도출 되었다. 조절변수로 설정 한 수용가능성의 경우 항공서비스 특성상 대기나 예상이 가능함을 사전 인지하고 있어 조절효과가 나타나지 않았으나 지각된 대기시간은 서비스 품질에 유의한 영향을 미친다는 결론에 도달했다. 본 연구 결과로부터 항공사의 대기관리 전략에 있어 실무적인 시사점을 도출할 수 있었다.

여성취업과 일·가정양립지원이 출산에 미치는 영향 (The Effects of Women's Labour Force Participation and Work-Family Reconciliation Support on Fertility)

  • 한영선;이연숙
    • Human Ecology Research
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    • 제53권1호
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    • pp.49-66
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    • 2015
  • This study analyzes the effects of women's labour force participation and work-family reconciliation support on life-cycle fertility in Korea. The analysis is based on the longitudinal data from Korean Labour and Income Panel Study (KLIPS), which include the available information on life-cycle fertility and employment history. Employing a dynamic model of fertility, we estimated the life-cycle fertility of all the 15-49 years old women considered in this study by using a duration model. The major results of this study were as follows: First, women's labour force participation had a negative effect on the first birth, second birth, and all births (transition to births starting at different parities). Women's employment tended to lengthen the interval between births. Second, the availability of maternal leave had a positive effect on the first birth and all births for working women. Providing maternal leave to working women decreased the opportunity cost of childbearing and in turn, reduced the interbirth interval of women. However, the availability of parental leave had no significant effect on the births of working women. Third, the financial support for childcare had a positive effect on the first birth and all births. The economic support for childcare led to the reduction in the interbirth interval of women by increasing the probability of births. The use of a childcare center for the first child, which substitutes for the time that women needed to take care of their children, classified as time-intensive consumption goods, did not have any effect on the second birth. Fourth, the part-time employment of women had a positive effect on the second birth. A flexible working time schedule tended to decrease the interval between the first and the second births.

Block Filtering과 QFT를 이용한 실시간 음장 효과구현 (Real-Tim Sound Field Effect Implementation Using Block Filtering and QFT)

  • 손성용;서정일;한민수
    • 대한음성학회지:말소리
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    • 제51호
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    • pp.85-98
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    • 2004
  • It is almost impossible to generate the sound field effect in real time with the time-domain linear convolution because of its large multiplication operation requirement. To solve this, three methods are introduced to reduce the number of multiplication operations in this paper. Firstly, the time-domain linear convolution is replaced with the frequency-domain circular convolution. In other words, the linear convolution result can be derived from that of the circular convolution. This technique reduces the number of multiplication operations remarkably, Secondly, a subframe concept is introduced, i.e., one original frame is divided into several subframes. Then the FFT is executed for each subframe and, as a result, the number of multiplication operations can be reduced. Finally, the QFT is used in stead of the FFT. By combining all the above three methods into our final the SFE generation algorithm, the number of computations are reduced sufficiently and the real-time SFE generation becomes possible with a general PC.

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문제해결 과정의 특이성이 문제해결 시간에 미치는 영향 (The Effect of the Peculiarity of the Problem-solving Process on the Problem-solving Time)

  • 손달호
    • 산업공학
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    • 제7권2호
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    • pp.121-132
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    • 1994
  • Despite extensive research on various factors affecting the effectiveness of decision support systems (DSS), considerable ambiguity still exists regarding the role and influence of the experience on the given task and the decision support system. Although researchers have advocated DSS effectiveness as a multi-dimensional construct, specific results regarding the effect of the familiarity in the task and the DSS on the problem-solving time is still lacking. The study reported here attempts to find the effect of the peculiarity of the problem-solving process on the problem-solving time. The results of the study highlight that the expertise in both the task and the DSS have made the shortage of the problem-solving time. However, more research about the generalized performance measure on the DSS is required.

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실시간 다물체 차량 해석을 위한 준정적법의 컴플라이언스 효과 모델링 (Compliance Effect Modeling based on Quasi-static Analysis for Real-time Multibody Vehicle Dynamics)

  • 정완희;하경남;김성수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.1003-1008
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    • 2007
  • Compliance effect consideration method for real-time multibody vehicle dynamics is proposed using quasi-static analysis. The multibody vehicle model without bush elements is used based on the subsystem synthesis method which provides real-time computation on the multibody vehicle model. Reaction forces are computed in the suspension subsystem. According to deformation from the quasi-static analysis using reaction forces and bush stiffness, suspension hardpoint locations and suspension linkage orientation are changed. To validate the proposed method, quarter car simulations of McPherson strut and multilink suspension subsystems. Full car bump run simulations are also carried out comparing with the ADAMS vehicle model with bush elements. CPU times are also measured to see the real-time capabilities of the proposed method.

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고양이에서 진정제 및 마취제가 Barium Sulfate의 위 십이지장 통과시간에 미치는 영향 (Effect of Chemical Restraint Drugs on Gastroduodenal Transit Time of Barium Sulfate in Cats)

  • 윤정희;성재기
    • 한국임상수의학회지
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    • 제6권1호
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    • pp.173-184
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    • 1989
  • The effect of propionylpromazine, acepromazine maleate, ketamine HCI, xylazine HCI, and pentobarbital sodium as chemical restraint drugs on the transit time of barium sulfate through the stomach and duodenum in 24 healthy cats was investigated. In the present study, propionylpromazine, acepromazine maleate, and ketamine HCI did not reveal significant effect on the gastroduodenal transit time, but xylazine HCI and pentobarbital sodium pro-longed the gastroduodenal transit time markedly compared with control group. Therefore it is concluded that propionylpromazine, acepromazine maleate, and ketamine HCI could be selected for upper gastrointestinal radiographs. but xylazine HCI and pentobarbital sodium should be avoided.

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