• 응용통계연구
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• 제10권1호
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• pp.105-119
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• 1997

일원배열형태의 가산 자료집합에서 각 군의 평균을 이용하여 처리효과를 비교할 수 있다. Barnwal과 Paul(1988)은 각 군의 산포모수가 같다는 가정 아래에서 처리에 따른 차이를 검정하는 우도검정통계량과 $C(\alpha)$ 통계량을 유도하였는데 본 연구에서는 이러한 가정이 만족되지 않아도 검정할 수 있도록 통계량을 일반화하였다. 또한 음이항분포 대신 Efron(1986)의 이중지수계 포아송 모형을 도입하여 새로운 통계량을 제시하였다. 모의실험을 통해 이중지수계 포아송 모형으로부터 유도된 $C(\alpha)$ 통계량이 어느 경우에나 적합함을 밝혔다.

• 대한산업공학회지
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• 제32권3호
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• pp.200-209
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• 2006

Load building is an important step to make the delivery supply chain efficient. We present a family of load makeup algorithms using market based control strategy, named LoadMarket, in order to build efficient loads where each load consists of a certain number of finished products having destinations. LoadMarket adopts Clark-Wright algorithm for generating initial endowment for Load Traders who cooperate to minimize either total travel distance or the variance with respect to the travel distances of loads by means of the spot market or double-sided auction market mechanism. The efficiency of the LoadMarket algorithms is illustrated using simulation based experiments.

• Korean Journal of Mathematics
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• 제26권3호
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• pp.483-501
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• 2018

In this paper, we present some recent results on weighted pointwise convergence and the rate of pointwise convergence for the family of nonlinear double singular integral operators in the following form: $$T_{\eta}(f;x,y)={\int}{\int\limits_{{\mathbb{R}^2}}}K_{\eta}(t-x,\;s-y,\;f(t,s))dsdt,\;(x,y){\in}{\mathbb{R}^2},\;{\eta}{\in}{\Lambda}$$, where the function $f:{\mathbb{R}}^2{\rightarrow}{\mathbb{R}}$ is Lebesgue measurable on ${\mathbb{R}}^2$ and ${\Lambda}$ is a non-empty set of indices. Further, we provide an example to support these theoretical results.

• 대한수학회보
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• 제54권1호
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• pp.29-42
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• 2017

In this work, four circulant and quadratic double circulant (QDC) constructions are applied to the family of the rings $R_{k,m}$. Self-dual binary codes are obtained as the Gray images of self-dual QDC codes over $R_{k,m}$. Extremal binary self-dual codes of length 64 are obtained as Gray images of ${\lambda}-four$ circulant codes over $R_{2,1}$ and $R_{2,2}$. Extremal binary self-dual codes of lengths 66 and 68 are constructed by applying extension theorems to the ${\mathbb{F}}_2$ and $R_{2,1}$ images of these codes. More precisely, 10 new codes of length 66 and 39 new codes of length 68 are discovered. The codes with these weight enumerators are constructed for the first time in literature. The results are tabulated.

• 가정과삶의질연구
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• 제21권5호
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• pp.1-12
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• 2003

Determinants of consumption patterns of elderly couple and elderly single were investigated using the 1996 National Survey of Family Income and Expenditure by National Statistical Office. There were large differences in consumption patterns between the elderly couple and single in terms of monthly expenditures and average budget shares of individual consumption items. Consumption functions of individual items were estimated using double-log function. Major determinants of consumption functions were income, overspending behavior, educational level of householder, and net worth for both groups, householder's job status and city residence mainly for elderly couple, and age of householder mainly for elderly single. In addition, income elasticity of elderly households was larger than net worth elasticity for all consumption items.

• Applied Microscopy
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• 제24권4호
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• pp.107-114
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• 1994

The Rotaviruses are members of the family Reoviridae and are the major cause of severe childhood gastroenteritis worldwide. Recently, electron microscopy has been used to detect non-group A rotaviruses to determine a relatively high resolution structure of the rotavirion. Mature, infectious virions(double-shelled particles) have a diameter of approximately 70nm, and have a capsid structure composed of two concentric protein layers. We have studied patient's stool specimen by negative staining technique complete removal of sucrose suspension. This negative staining technique that could be carried out in about 30 minutes and that could be used with crude stool specimen was an advantage of major significance. Removal of sucrose in the sample by has been completed washing with distilled of sucrose and by washing with distilled water. Ultrastructurally, typical feature of rotavirus has a double capsid construction with an inner capsid of 55nm and on outer 65-70nm diameter can be clearly demonstrated.

• Journal of Communications and Networks
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• 제12권1호
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• pp.43-51
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• 2010

IEEE 802.11 defines distributed coordination function (DCF), which is characterized by CSMA/CA and binary exponential backoff (BEB) algorithm. Most modifications on DCF so far have focused on updating of the contention window (CW) size depending on the outcome of own frame transmission without considering freezing periods experienced in the backoff interval. We propose two simple but novel schemes which effectively utilize the number of freezing periods sensed during the current backoff interval. The proposed schemes can be applied to DCF and its family, such as double increment double decrement (DIDD). Saturation throughput of the proposed schemes is analyzed by means of Bianchi's Markovian model. Computer simulation validates the accuracy of the analysis. Numerical results based on IEEE 802.11b show that up to about 20% improvement of saturation throughput can be achieved by combining the proposed scheme with conventional schemes when applied to the basic access procedure.

• Structural Engineering and Mechanics
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• 제3권5호
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• pp.445-462
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• 1995

Previous studies of a stepped cantilever with two straight segments under a suddenly applied constant force (a step load) applied at its tip have shown that the validity of deformation mechanisms is governed by certain geometrical restrictions. Single and double-hinge mechanisms have been proposed and it is shown in this paper that for a stepped cantilever with a stronger tip segment, i.e. $M_{0.1}$ > $M_{0.2}$, where $M_{0.1}$ and $M_{0.2}$ are the dynamic fully plastic bending moments of the tip and root segments, respectively, the family of possible yield mechanisms is expanded by introducing new double and triple-hinge mechanisms. With the aid of these mechanisms, it is shown that all initial deformations can be derived for a stepped cantilever regardless of its geometry and the magnitude of the dynamic force applied.

• 한국사회복지학
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• 제67권4호
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• pp.279-299
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• 2015

본 연구의 목적은 노인장기요양서비스를 이용하는 부양가구원과 여성가구원의 노동공급효과를 확인하는데 있다. 노인장기요양보험제도의 공식적 돌봄 서비스가 부양가구원들의 비공식적 돌봄을 대체한다면, 이는 부양가구원들의 시간제약을 변화시켜 노동공급을 증가시킬 것이다. 따라서 이러한 노동공급효과는 각국의 공적 돌봄 서비스의 제도적 수준에 따라 달라질 수 있다. 지금까지 서구국가들에서는 이에 대한 연구가 활발히 전개되어 왔으나, 이러한 실증분석들은 혼재된 결과를 보인다. 선행연구들에서는 무엇보다 방법론상 내생성의 문제가 지속적으로 제기되어 왔다. 본 연구는 이러한 문제를 해결하고자 유사실험설계인 PSM(Propensity Score Matching)과 DD(Double Difference) 결합모형을 활용하여 선택편의를 최소화하였다. 한국복지패널 3차, 9차 데이터를 활용한 분석 결과, 한국의 노인장기요양보험제도의 노동공급효과는 나타나지 않았다. 단순이중차이분석에서는 노동시간과 근로소득이 유의미하게 증가한 것으로 나타났지만, 더 엄격하다고 볼 수 있는 이중차이 고정효과모형분석에서는 그 효과가 나타나지 않았다. 이를 서구의 경험적 연구결과에 비춰보면, 한국의 공적 돌봄서비스인 노인장기요양보험제도가 비공식적 돌봄을 대체하지 못하고 일부만을 보완하는 수준에 머물러 있는 것이라고 해석할 수 있다. 본 연구의 분석결과는 그동안 제기되어온 노인장기요양서비스의 급여불충분성에 대한 증거가 될 수 있으며, 노인장기요양서비스의 제도적 배열이 대상자 및 부양가족의 욕구에 맞도록 선택되어져야 한다는 함의를 가진다.

• Journal of Ginseng Research
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• 제42권4호
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• pp.571-576
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• 2018

Background: Korean Red Ginseng (KRG) has been used in Asia for its various biological effects, but no studies have investigated the safety of its long-term intake. Therefore, the present study evaluated the safety of KRG intake for 24 weeks. Methods: We randomized 1,000 participants in a 1:1 ratio into two groups, which were treated daily with 2 g of KRG or a placebo for 24 weeks. The primary endpoint was all adverse events and adverse drug reactions (ADRs) that occurred after KRG or placebo administration, which were reported at week 4, 12, and 24 after the baseline visit. Results: In total, 192 and 211 participants experienced adverse events in the KRG and placebo groups (39.2% and 42.0%, respectively; p = 0.361), and 59 and 57 KRG- and placebo-treated individuals reported ADRs (12.0% and 11.4%, respectively; p = 0.737). The frequently occurring ADRs were pruritus (2.0%), headache (1.6%), diarrhea (1.4%), and dizziness (1.2%) in the KRG group and pruritus (2.0%), headache (1.8%), dizziness (1.6%), rash (1.4%), and diarrhea (1.2%) in the placebo group. Discontinuation of drug administration due to ADRs was reported in 13 participants, six (1.2%) and seven (1.4%) in the KRG and placebo groups, respectively (p = 0.814). No significant abnormal changes were revealed by anthropometric, laboratory, and vital sign measurements in the KRG group compared with those in the placebo group. Conclusion: The present study confirms the safety and tolerability of daily intake of 2 g of KRG for 24 weeks by healthy adults.