We examine a single machine scheduling problem with step-improving jobs in which job processing times decrease step-wisely over time according to their starting times. The objective is to minimize total completion time which is defined as the sum of completion times of jobs. The total completion time is frequently considered as an objective because it is highly related to the total time spent by jobs in the system as well as work-in-progress. Many applications of this problem can be observed in the real world such as data gathering networks, system upgrades or technological shock, and production lines operated with part-time workers in each shift. Our goal is to develop a scheduling algorithm that can provide an optimal solution. For this, we present an efficient branch and bound algorithm with an assignment-based node design and tight lower bounds that can prune branch and bound nodes at early stages and accordingly reduce the computation time. In numerical experiments well designed to consider various scenarios, it is shown that the proposed algorithm outperforms the existing method and can solve practical problems within reasonable computation time.

This study is about the ungramamtical use of 〈ttaemune (때문에)〉. Because 〈ttaemun (때 문)〉 is a bound noun, a noun modifier is essential before it. So 〈ttaemune〉 also needs a modifier before it. But on the actual language usage, 〈ttaemune〉 is often used without modifiers. This phenomenon appears to be mainly limited to cases where 〈ttaemune〉 is used between sentences. That is, in this case, 〈ttaemune〉 is used as the conjunction like 〈geulaeseo (그래서)〉. Previous research has treated this ungrammatical aspect of 〈ttaemune〉 as a representative example of the degrammaticalization phenomenon. In other words, it has been understood that because the bound noun 〈ttaemun〉 has gained independency, 〈ttaemune〉 is used without modifiers before it. However, it is difficult to accept degrammaticalization discussions positively in the following respects: this phenomenon is not so common as to be recognized as a particular grammatical phenomenon, and if this is due to the independence of 〈ttaemun〉, this should also occur in other cases where 〈ttaemun〉 is combined, but this is not the case. So, I think it is right to treat them as objects that need to be corrected rather than treated within language norms.

Synthetic membranes, based on polymers or inorganic membranes, are now used in a wide variety of gas separations. For gas separation membranes, during the 1980’s, permeability data on six common gases were complied, and the tradeoff relationship was analyzed. The upper bound relationship was established empirically. Recognizing the exquisite permeability and selectivity of biological membranes and the deleterious nature of broad pore size distributions and flexibility of polymer chains on permeability/selectivity combinations, a number of approaches have been pursued to develop membranes with better transport and separation properties. There has been an evolution in design of materials for both gas and liquid separation membranes, brought about by advances in structural control of materials and by better understanding of natural membranes.

We focus on the fire scheduling problem (FSP), the problem of determining the sequence of targets to be fired at, for the objective of minimizing makespan to achieve tactical goals. In this paper, we assume that there are m available weapons to fire at n targets (> m) and the weapons are already allocated to targets. One weapon or multiple weapons can fire at one target and these fire operations should start simultaneously while the finish time of them may be different. We develop several dominance properties and a lower bound for the problem, and suggest a branch and bound algorithm implementing them. Also, In addition, heuristic algorithms that can be used for obtaining an initial upper bound in the B&B algorithm and for obtaining good solutions in a short time were developed. Computational experiments are performed on randomly generated test problems and results show that the suggested algorithm solves problems of a medium size in a reasonable amount of computation time. The proposed lower bound, the dominance properties, and the heuristics for upper bound are tested in B&B respectively, and the result showed that lower bound is effective to fathoming nodes and the dominance properties and heuristics also worked well. Also, it is showed that the CPU time required by this algorithm increases rapidly as the problem size increases. Therefore, the suggested B&B algorithm would be limited to solve large size problems. However, the employed heuristic algorithms can be effectively used in the B&B algorithm and can give good solutions for large problems within a few seconds.

PURPOSES : The noise, which is typically generated by fast moving vehicles, can be intercepted by installing a noise barrier with a soundproof panel. However, reflections from the panels cause secondary noise, and hence lower the effectiveness of the panels. In this study, the reduction of reflection noise by considering the shape, especially zigzag one, of the soundproof panel have been evaluated. METHODS : The simulation model used in this study was Nord2000, which simulates real-road situations effectively. Based on the simulation results, the joining angle of 133。with the pattern width (a) equal to 2 m and the projection height (b) equal to 0.5 m was adapted in the zigzag shape as the best profit designing factors. RESULTS: The measuring results at middle height, 15 m showed reduction at all points except the point with average -1.6 dB. At a greater height of 30 m, 2 points showed reduction. A real-sized facility was constructed to investigate the reflected sound from a zigzag shaped panel up to the height of 5 m. CONCLUSIONS: The reduction effects were detected in all the receive points in the range of 2-6 m distances and 1-5 m heights comparing the plane panel. Compared to plane panel, the noises are reduced at an average of 2.4 dBA.

본 연구는 N2/NF3 분리를 위해 다양한 상업용 고분자를 이용하여 최초로 실증적 N2/NF3 분리상한선을 정의하였고, 6FDA–DAM:DABA(3:2), Teflons AF 2400, PTMSP가 가장 우수한 분리성능을 보여주었다. 또한, Freeman이론에 기반한 이론적 N2/NF3 상한선을 결정하였고, 이를 통해 실증적 상한선의 타당성을 증명하였다. 마지막으로, N2/NF3 분리성능 향상을 위해, Matrimid® 5218에 ZIF-8을 혼합한 하이브리드 분리막을 개발하였다. 용매, 입자크기 및 리간드가 하이브리드 분리막의 N2/NF3 분리성능에 미치는 영향을 연구하였다.

Toxicity of 3-MCPD that comes from food manufacture and processing is well-known. Recent studies reported that 3-MCPD fatty acid ester which is formed by metabolic material was 10~2000 times as much as 3-MCPD in food. This study made analysis method of 3-MCPD fatty acid esters by recent research and laboratory work, and determined the content of 3-MCPD and 3-MCPD fatty acid esters in sources and meat processing products. 3-MCPD fatty acid esters were analysed by GC/MS, which were hydrolyzed from fatty acid and then transferred 3-MCPD was extracted and reacted with derivative subject. As a result of analysis method validation, LOD was 5.4ppb,LOQ was 9.0ppb.

3-MCPD created in manufacture process was regulated in our country about soy sauce and HVP. The latest paper reported that Bound 3-MCPD is created as intermediate. Germany common risk assesment reported that Bound 3-MCPD must be reduced because Bound 3-MCPD can be created in estimation circle when this is hydrolyzed in human body, but the data about the toxity of Bound 3-MCPD is lack. Therefore, We analysis about 209 items food such as soy sauce, seasoning food and meat-eating manufactured goods using bound 3-MCPD analysis method developed recently. As result of survey, bound 3-MCPD detected in 8 items among 44 traditional sauce (0.02~0.28ppm), 8 of soup 12 items (0.01~0.96ppm), in 22 items of sauce 60 items (0.01~0.55ppm), in 16 items of meateating manufactured foods 30 items (0.04~0.18ppm), in 20 items of snack cookies 28 items (0.09~1.43ppm), in 8 in roasted oil foods 10 items (0.04~1.22ppm), in 6 items of peanut processed food 10 items (0.06~0.25ppm), in 1 of vegetable cream 15 items (0.05ppm). Detected level was lower than the result of monitored by other countries.

In this paper, we consider a two-machine re-entrant permutation flowshop scheduling problem with the objective of minimizing total flowtime, and suggest branch and bound algorithms for the scheduling problem. In this scheduling problem, each job must be p

This paper considers the simultaneously firing model for the artillery operations. The objective of this paper is to find the optimal fire sequence minimizing the final completion time of the firing missions of multiple artillery units for multiple target

이 논문에서는 모바일 통신망에서 호 손실율의 가능성 분포에 기초하여 최대 손실률을 추정하는 방법을 제안한다. 호 손실률 가능성 분포는 관측된 호 손실률을 이용하여 퍼지추론으로 추정한다. 퍼지규칙의 소속 함수는 신경망의 EBP(error backpropagation ) 알고리즘으로 튜닝하고, 퍼지추론은 퍼지집합의 가중치 평균에 기초하여 호 손실율의 상한계를 추정한다. 이 방법은 과도한 CDR(Call Dropping Ratio)의 추정을 방지할 수 있고, 추정된 CDR 이 관측된 CDR보다 작을 때는 실시간적으로 자기보상을 실시하여 관측된 CDR이 추정된 CDR을 초과하는 경우가 없게 한다. 시뮬레이션을 통하여 제안된 방법이 관측된 호 손실률에 기초하여 상한계값을 잘 추정해냄을 보인다.

In this paper, a best-first branch and bound algorithm based upon the bottom-up approach for the unweighted unconstrained two-dimensional cutting problem is proposed to find the optimal solution to the problem. The algorithm uses simple and effective meth

The purpose of this study was to evaluate the diet quality of the menus delivered by 17 free meal service centers for the low-income home-bound elderly in Chung- cheong buk-Do. Statistical data analysis was compleleted using the SPSS package program for descriptive analysis, T-test, and ANOVA. The meals offered by free meal service centers were not met the 1/3 recommended dietary allowances in calcium and vitamin B2. There were significant differences between dependent variables(nutrient content, nutrient density, nutrient deficiency, NAR, MAR, food group intake patterns) and independent variables (operation type, operation status, operation period, nutritionist, food cost).