• International Journal of Reliability and Applications
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• 제7권2호
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• pp.101-110
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• 2006

Let E be a set of n quantitative observations under the time control. The interval of time is to be split into several subintervals such that the observations in each subinterval are almost similar, whereas the observations between the subintervals are very dissimilar. The corresponding time-subintervals become periods or phases of the development that exist in the underlying phenomenon. Aboukalam(2005) proposes a robust solution based on some initial subintervals and a technique for combining any two successive groups in that starter using a t-test under a fixed significant level ($\alpha$). The inconvenience is that; the technique reliability is not released from the level $\alpha$ which must not be defined apart from the number of the periods that is, in its turn, unknown. To avoid this, we propose what so called; most significant periods solution. The new technique constructs its own initial subintervals and uses another way for combining the groups. However, the way of determining and treating outliers has not changed. This paper conducts many empirical simulations using different possible time dominated data in order to illustrate the reliability of the proposed technique. Finally, we apply both techniques on some real time dominated data to explain the advantage of the proposal.

• International Journal of Computer Science & Network Security
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• 제21권12호
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• pp.248-256
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• 2021

Now that we're in the big data era, data has taken on a new significance as the storage capacity has exploded from trillion bytes to petabytes at breakneck pace. As the use of cloud computing expands and becomes more commonly accepted, several businesses and institutions are opting to store their requests and data there. Cloud storage's concept of a nearly infinite storage resource pool makes data storage and access scalable and readily available. The majority of them, on the other hand, favour a single cloud because of the simplicity and inexpensive storage costs it offers in the near run. Cloud-based data storage, on the other hand, has concerns such as vendor lock-in, privacy leakage and unavailability. With geographically dispersed cloud storage providers, multicloud storage can alleviate these dangers. One of the key challenges in this storage system is to arrange user data in a cost-effective and high-availability manner. A multicloud storage architecture is given in this study. Next, a multi-objective optimization problem is defined to minimise total costs and maximise data availability at the same time, which can be solved using a technique based on the non-dominated sorting genetic algorithm II (NSGA-II) and obtain a set of non-dominated solutions known as the Pareto-optimal set.. When consumers can't pick from the Pareto-optimal set directly, a method based on Principal Component Analysis (PCA) is presented to find the best answer. To sum it all up, thorough tests based on a variety of real-world cloud storage scenarios have proven that the proposed method performs as expected.

• Journal of information and communication convergence engineering
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• 제9권1호
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• pp.105-109
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• 2011

In this paper, we study the dominating-free sest which is defined as follows: k points called servers and n points called clients in the plane are given. For a point p in the plane is said to be dominated by a client c if for every server s, the distance between s and p is greater than the distance between s and c. The dominating-free set is the set of points in the plane which aren't dominated by any client. We present an O(nklogk+$n^2k$) time algorithm for computing the dominating-free set under the $L_1$-metric. Specially, we present an O(nlogn) time algorithm for the problem when k=2. The algorithm uses some variables and 1-dimensional arrays as its principle data structures, so it is easy to implement and runs fast.

• 한국심리학회지:여성
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• 제16권3호
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• pp.303-329
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• 2011

우리나라는 여성의 교육참여율이 과거 어느 때보다 높은데 비해 인력활용율은 OECD국가 중 최저 수준에 머물고 있다. 이렇게 고학력 여성인력의 활용률이 저조한 원인으로 진로상담영역에서 '진로선택'과 관련된 원인에 주목하였다. 전통적으로 직업을 여성중심 또는 남성 중심 직업으로 분류할 때 아직까지도 많은 여성들이 남성중심 직업을 회피하는 경향이 있으며, 이러한 편중현상을 해소해야만 다양한 인력활용이 가능할 것이다. 이를 위해 본 연구에서는 남성중심적 직업을 희망하는 여대생들에 대한 질적 연구를 통해 이들의 경험구조 및 직업결정 과정을 밝히고, 그 과정에서 부정적 또는 긍정적으로 작용하는 요인들을 밝혀 여성 진로지도에 활용하고자 하였다. 남성중심적 직업을 선택하며 취업준비중인 대학교 3학년 이상 여학생 8명을 심층면접한 녹음자료를 분석한 결과 총 61개의 개념과 27개의 하위범주, 12개의 범주가 도출되었다. 범주들을 토대로 핵심범주인 '특별한 삶을 위해 의지를 갖고 도전해 나가기'가 도출 되었다. 또한 패러다임 분석을 통해 인과적 조건, 중심현상, 맥락적 조건, 중재적 조건, 작용/상호작용 전략과 결과를 구분하였다. 과정 분석을 통해 기질과 포부 인식 단계, 내적결의 단계, 지지와 수용 단계, 도전과 극복의 순환 단계, 긍정과 확신의 단계로 총 5 단계의 직업결정 과정이 밝혀졌다. 논의에서는 연구의 의의와 제한점 및 후속연구에 대한 제안에 대해 언급하였다.

• 한국의류학회지
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• 제26권3_4호
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• pp.492-502
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• 2002

The purpose of this study was to investigate the advertising appeals and consumption values expressed on cosmetic advertisements in Adolescent's magazines from 1973 to 2000. The data for longitudinal content analysis were collected from Adolescent's magazine : Junior Joongang(1973.3∼1985.12), Highteen(1986.1∼1994.9), Cci(1994.l0∼2000.12). Collected data was consisted of 542 advertisements. 1. The product categories in cosmetics advertisements, the major were Base Make-up in the past but the number of Color Make-up, Functional Make-up, and Hair-related Products had increased in 1990s. Also, there were more increasing number of imported products than domestics. 2. The trend of appeals showed change according to time and society. Overall, a great many of cosmetic advertisements had emotional approach. Before the middle of the 1980's emotional approach had decreased, and mixed(rational and emotional) approach were dominated in 1990s. 3. The major consumption values in cosmetics advertisements were effective value. Especially, it had increased from 1990s. And esthetic value was dominated in the middle of the 1970s.

• 한국대기환경학회지
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• 제8권2호
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• pp.138-145
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• 1992

Dependence of the standard deviation of wind direction fluctuations, ${\sigma}_{\theta}$, on atmospheric stability, averaging time and topography were analysed with the data measured at three sites, Youngjongdo beach of the Yellow Sea, Chuncheon basin and Doam-Dam valley. The results show that the mean value of ${\sigma}_{\theta}$ is large in complex terrain, the Doam-Dam site. It is notable that the large value of ${\sigma}_{\theta}$ at night is associated with the low wind speed and the strong stable condition. In order to study the long-period fluctuations of the wind direction, ${\sigma}_{\theta}$ for longer than 10 minutes averaging time was further analysed using the data obtained at the Chuncheon basin. At the averaging time shorter than 60 minutes, larger ${\sigma}_{\theta}$ is associated with longer averaging time in the strong stable condition. However, ${\sigma}_{\theta}$ was not affected significantly by wind speed and averaging time in neutral conditions. The results of the spectrum analysis for the time series data of wind direction showed that low-frequency fluctuations ranging from 10 to 60 minutes were dominated at the Chuncheon basin in strong stable condition.

• 한국통신학회논문지
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• 제39A권3호
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• pp.121-126
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• 2014

Demand of the data storage becomes more and more growing. This requests the next generation of storage devices to have the dominated storage capability associated with superfast read/write rate. Holographic data storage (HDS) is investigated for a long time and is considered to be a candidate for the future storage system. However, it has two-dimensional intersymbol interference that conventional one-dimensional detection solutions have not yet handled strictly because of the complexity level of system as well as the cost. We propose a new scheme that combines iterative soft output Viterbi algorithm with noise filter for improving the bit error rate performance of HDS.

• 생태와환경
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• 제42권4호
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• pp.487-494
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• 2009

We compared spatial and temporal variations of water chemistry between high-flow year ($HF_y$) and low-flow year ($LF_y$) in an artificial lentic ecosystem of Daechung Reservoir. The differences in the rainfall distributions explained the variation of the annual inflow and determined flow characteristics and water residence time and modified chemical and biological conditions, based on TP, suspended solids, and chlorophylla, resulting in changes of ecological functions. The intense rainfall and inflow from the watershed resulted in partial disruption of thermal structure in the metalimnion depth, ionic dilution, high TP, and high suspended solids. This condition produced a reduced chlorophyll-a in the headwaters due to low light availability and rapid flushing. In contrast, reduced inflow and low rainfall by drought resulted in strong thermal difference between the epilimnion and hypolimnion, low inorganic solids, high total dissolved solids, and low phosphorus in the ambient water. The riverine conditions dominated the hydrology in the monsoon of $HF_y$ and lacustrine conditions dominated in the $HF_y$. Overall data suggest that effective managements of the flow from the watershed may have an important role in the eutrophication processes.

• 대한전기학회논문지:전력기술부문A
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• 제54권6호
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• pp.293-305
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• 2005

This paper describes an improved Prony method in its speed, accuracy and reliability by efficiently determining the optimal sampling interval with use of DFT (discrete Fourier transformation). In the Prony method the computation time is dominated by the size of the linear prediction matrix, which is given by the number of data times the modeling order The size of the matrix in a general Prony method becomes large because of large number of data and so does the computation time. It is found that the Prony method produces satisfactory results when SNR is greater than three. The maximum sampling interval resulting minimum computation time is determined using the fact that the spectrum in DFT is inversely proportional to sampling interval. Also the process of computing the modes is made efficient by applying Hessenberg method to the companion matrix with complex shift and computing selectively only the dominant modes of interest. The proposed method is tested against the 2003 KEPCO system and found to be efficient and reliable. The proposed method may play a key role in monitoring in real time low frequency oscillations of power systems .

• 한국환경과학회지
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• 제31권6호
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• pp.525-533
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• 2022

Baengnyeongdo, located within the Asian dust stream, is an ideal place to analyze Asian dust moving into the West Sea due to its low emission of artificial pollutants. Baengnyeongdo is being used to analyze the vertical distribution of dust from the lower atmosphere to the upper layer through remote observation. This study compared the ground concentration of dust between Baengnyeongdo and the metropolitan area, estimated the lag time of transport of Asian dust from Baengnyeongdo to the metropolitan area, and examined the homogeneity of upper winds using the rawinsonde method. The results showed that the cross correlation coefficient was higher and the lag time was shorter for each observation station when the distance from Baengnyeongdo was shorter. The upper wind at Baengnyeongdo is dominated by the west/northwest wind. It is the basis for the correlation of dust concentration between Baengnyeongdo and the metropolitan area located to the east. In the future, upper wind data and Asian dust concentration data over the West Sea and Baengnyeongdo are expected to contribute to research related to the movement and prediction of Asian dust and preparation for Asian dust in the metropolitan area.