• 한국통신학회논문지
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• 제37A권10호
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• pp.895-902
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• 2012

본 논문에서는 비선형 전력증폭기(PA:power amplifier)의 AM/PM 비선형 왜곡특성을 포함하는 군 지연을 보상하는 새로운 등화기를 제안한다. 군 지연 특성은 각 주파수 성분에 따라 서로 다르게 나타나는 상수가 아닌 비선형 시간지연이다. 전력증폭기에서 발생되는 AM/PM 특성으로 인한 위상 왜곡 현상은 군 지연을 증가시키는 주요한 요인이다. 이러한 군 지연 왜곡으로 신호 성상도에서 신호는 퍼지면서 회전하게 된다. 위와 같은 문제점을 고려하여 각 주파수 성분에 따라 다르게 나타나는 비선형 시간지연을 정적인 군지연으로 구분하고, PA의 AM/PM 특성인 입력신호 크기에 따라서 위상 천이가 다르게 발생하는 것을 동적인 군 지연으로 구분한다. 정적인 군 지연은 주파수 영역에서 Type-Based 방법으로 위상 왜곡을 추정 및 보상하고 동적인 군 지연은 시간영역에서 위상회전을 보상한다. 제안된 군 지연 보상기법으로 전력증폭기의 AM/PM 특성을 포함한 군 지연 특성을 충분히 보상할 수 있음을 확인하였다.

• 한국보육지원학회지
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• 제1권1호
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• pp.167-189
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• 2005

본 연구에서는 영아의 만족지연능력과 만족지연전략 및 어머니의 통제성간의 관계를 알아보았다. 연구대상은 18-36개월의 영아였으며 만족지연능력 측정 실험은 Mischel(1974)이 고안한 자기 만족지연 실험을 Rha(1999)가 연령에 맞게 번안한 것을 사용하였다. 만족지연능력에 사용되는 전략으로는 직접응시 전략과 주의분산 전략으로 분류하여 관찰하였으며 어머니의 양육방식은 조복희, 이진숙, 이홍숙 그리고 권희경(1999)에 의해 개발된 척도의 일부인 통제 13문항을 발췌하여 사용하였다. 연구결과 영아의 월령이 증가함에 따라 만족지연능력이 증가하며, 영아가 사용하는 만족지연전략은 월령이 높아질수록 주의분산전략을 더 많이 사용하는 것으로 나타났다. 또한 영아의 월령, 만족지연 전략인 직접응시 전략과 주의분산 전략은 영아의 만족지연능력에 유의미한 영향을 주었다.

• Nuclear Engineering and Technology
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• 제47권3호
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• pp.362-379
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• 2015

In this study, Nuclear Power Plant (NPP) construction schedule delay risk assessment methodology is developed and the construction delay risk is assessed for turnkey international NPP projects. Three levels of delay factors were selected through literature review and discussions with nuclear industry experts. A questionnaire survey was conducted on the basis of an analytic hierarchy process (AHP) and Relative Importance Index (RII) methods and the schedule delay risk is assessed qualitatively and quantitatively by severity and frequency of occurrence of delay factors. This study assigns four main delay factors to the first level: main contractor, utility, regulatory authority, and financial and country factor. The second and the third levels are designed with 12 sub-factors and 32 sub-sub-factors, respectively. This study finds the top five most important sub-sub-factors, which are as follows: policy changes, political instability and public intervention; uncompromising regulatory criteria and licensing documents conflicting with existing regulations; robust design document review procedures; redesign due to errors in design and design changes; and worldwide shortage of qualified and experienced nuclear specific equipment manufacturers. The proposed combined AHP-RII methodology is capable of assessing delay risk effectively and efficiently. Decision makers can apply risk informed decision making to avoid unexpected construction delays of NPPs.

• 대한교통학회:학술대회논문집
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• 대한교통학회 1998년도 제34회 추계 학술발표회
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• pp.298-298
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• 1998

The delay on two-lane, Two-way roads is a very important factor which tends to cause relatively high driver loads and too much delay often leads to traffic accidents. In this study a generalized form of delay estimation model was developed based on constant slow moving vehicle speeds, 100% no-passing zone, and flat terrain highway sections. To validate the model, a comparison was made with John Morrall's SMV(Slow Moving Vehicle)model as well as with TWOPAS model. Also a sensitivity analysis was performed to check accuracy of the model. It was found that the model was easy to apply and yet provided reasonable results for experimental conditions specified in the study. It was recommended that speed calculation procedure of the model be improved by further studies, so that the effect of speed acceleration or deceleration according to highway geometries on delay could be analyzed more accurately.

• Journal of Communications and Networks
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• 제6권4호
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• pp.352-361
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• 2004

In this paper, we study how to achieve the maximum capacity under delay constraints for large mobile wireless networks. We develop a systematic methodology for studying this problem in the asymptotic region when the number of nodes n in the network is large. We first identify a number of key parameters for a large class of scheduling schemes, and investigate the inherent tradeoffs among the capacity, the delay, and these scheduling parameters. Based on these inherent tradeoffs, we are able to compute the upper bound on the maximum per-node capacity of a large mobile wireless network under given delay constraints. Further, in the process of proving the upper bound, we are able to identify the optimal values of the key scheduling parameters. Knowing these optimal values, we can then develop scheduling schemes that achieve the upper bound up to some logarithmic factor, which suggests that our upper bound is fairly tight. We have applied this methodology to both the i.i.d. mobility model and the random way-point mobility model. In both cases, our methodology allows us to develop new scheduling schemes that can achieve larger capacity than previous proposals under the same delay constraints. In particular, for the i.i.d. mobility model, our scheme can achieve (n-1/3/log3/2 n) per-node capacity with constant delay. This demonstrates that, under the i.i.d. mobility model, mobility increases the capacity even with constant delays. Our methodology can also be extended to incorporate additional scheduling constraints.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.125-129
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• 2010

The ultimate goal of construction is to complete the given work in the most economical and safest way within the required construction period while meeting the quality standards specified in the design drawing. There are a few characteristics of finish work. First, executed in subdivided processes, finish work involves a very diverse and complex structure. Second, there are no criteria for each segmented process with regard to the appropriate time of input. Third, it is not very necessary to set priorities for lead and lag works. This study intends to provide information on the completion of a project in accordance with the required duration by setting priorities in the delay of each detailed process of finish work to minimize delay in finish work. In this study, finish work is divided into wet work and other types of finish work, and the importance of each process is classified based on the given details of each process. In addition, the study employs a survey to analyze delay factors of a designer, a constructor, and a supplier. Using the survey results, the study sets priorities in delay of final work to provide information on the completion of an apartment project within the planned construction period.

• 전기학회논문지
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• 제63권12호
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• pp.1690-1696
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• 2014

Network RTK generates spatial corrections by using differenced measurements from reference stations in the network, and the corrections are then provided to a rover. The rover, generally, uses linear interpolation, which assumes that the corrections at each reference station are spatially correlated, to obtain a precise correction of its location. However, an irregularity of the tropospheric delay is a real-world factor that violates this assumption. Tropospheric delay is a result of weather conditions, such as humidity, temperature and pressure, and it can cause spatial decorrelation when there are changes in the local climate. In this paper, we have defined the non-linear characteristics of the tropospheric delay between reference stations or user within a region as the "irregularity of tropospheric delay". Such an irregularity can negatively impact the network RTK performance. Therefore, we analyze the influence of the irregularity of tropospheric delay in network RTK based on meteorological data.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.496-501
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• 2006

작업 지연은 건설 사업의 확실성을 저하시키는 요소 중에 하나이다. 작업 지연의 원인 분류체계를 확립하고 관리 항목을 도출하는 것은 건설 사업의 경쟁력을 갖게 한다. 하지만 작업 지연 단계의 분류체계나 지연 원인 도출에 관한 연구는 미흡하다. 따라서 본 연구에서는 건설 사업에서 차지하는 비중이 높은 공동주택 건축공사를 대상으로 설문조사를 실시하고 이를 통해 작업 지연 원인을 파악하고 공종별 지연 요소를 도출한다. 그리고 지연 요소의 우선순위를 선정하여 작업 지연 요소를 효과적으로 제거하고 관리할 수 있는 중점 관리 항목을 제시한다.

• 한국의류학회지
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• 제32권5호
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• pp.766-776
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• 2008

The purpose of this study was 1) to identify the reasons for delay of decision making and the shopping information in internet shopping, 2) to classify consumers based on the clothing benefits, 3) and to examine the differences among consumer groups in the reasons for delay of decision making and the shopping information. The data were collected from a sample of 500 internet shopper aged from 20 to 40. This study used factor analysis, multiple regression analysis, Pearson's correlation analysis, cluster analysis and ANOVA. The results showed that the reasons for delay of decision making consisted of eight factors: Performance risk, Comparison shopping, Economic shopping, Social risk, Uncertainty, Expecting of market change, Product unsatisfaction, Passive shopping. The shopping information consisted of three factors: Product variety, Product information, Additional information. Five factors of clothing benefits were Economy, Figure compensation, Social position, Individuality, and Comfort. The respondents were classified into four groups by five factors of clothing benefits; Individuality seeking group, Low-benefits seeking group, Economy seeking group, Figure compensation/comfort seeking group. There were significant differences among groups in the reasons for delay of decision making and the shopping information among groups. Therefore, marketers need to provide different shopping information for delay closure by target groups.

• 융합경영연구
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• 제6권1호
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• pp.9-16
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• 2018

Purpose - Benefit delay type services have a characteristic of benefit delay that does not immediately appear at the time of delivery of service. Due to a characteristic of benefit delay, the customer's participation in the service delivery system is hindered, and the quality of service declines. As a result, customer satisfaction would be reduced. The purpose of this study is to construct an analytical framework to analyze a mechanism that promotes customer participation in benefit delay type services. Research design, data, and Methodology - Existing research has considered only the performance of service companies to enhance the quality of service and customer satisfaction. This study focused on customer participation as a factor affecting the quality of service and customer satisfaction and attempted to construct an analytical framework based on a theoretical perspective of motivational research. Results - By adopting the motivation theory, this research derived three concepts, the possibility of gaining benefits, the emotional experience, and the desire of benefit. And motivation is created when the three factors interact with each other. Conclusions - This paper has constructed an analytical framework for analyzing factors that promote customer participation in the benefit delay service and finally has proposed case study for further research.