• 대한조선학회논문집
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• 제49권1호
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• pp.68-78
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• 2012

A layout of an LNG FPSO should be elaborately determined as compared with that of an onshore plant because many topside process systems are installed on the limited area; the deck of the LNG FPSO. Especially, the layout should be made as multi-deck, not single-deck and have a minimum area. In this study, a multi-floor layout for the liquefaction process, the dual mixed refrigerant(DMR) cycle, of LNG FPSO was determined by using the optimization technique. For this, an optimization problem for the multi-floor layout was mathematically formulated. The problem consists of 589 design variables representing the positions of topside process systems, 125 equality constraints and 2,315 inequality constraints representing limitations on the layout of them, and an objective function representing the total layout cost. To solve the problem, a hybrid optimization method that consists of the genetic algorithm(GA) and sequential quadratic programming(SQP) was used in this study. As a result, we can obtain a multi-floor layout for the liquefaction process of the LNG FPSO which satisfies all constraints related to limitations on the layout.

• 한국정보과학회논문지:소프트웨어및응용
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• 제31권1호
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• pp.20-28
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• 2004

소프트웨어 개발 초기에 개발비용, 소묘인력과 기간을 추정하는 것은 소프트웨어공학 분야의 중요하면서도 어려운 문제이다. 기존 모델은 개발업체의 생산성 수준을 고려하지 않고 단순히 기능점수와 노력, 노력과 개발기간 관계에 대한 회귀분석을 통해 개발노력과 기간을 추정하는 모델을 제시하였다. 그러나 동일한 규모의 소프트웨어라도 개발업체의 생산성 수준에 따라 다른 노력의 양이 투입되며, 동일한 노력이 투입되더라도 생산성에 따라 개발기간이 달라진다. 생산성 수준을 고려하지 않은 제안된 모델들은 실제 개발될 프로젝트 적용에 제한점을 갖고 있다. 본 논문은 기존 모텔의 단점을 보완하기 위해 생산성을 고려하여 개발기간을 추정할 수 있는 모델들을 제안한다. 생산성에 기반 하여 다양한 방법으로 개발기간을 추정할 수 있는 모델을 제안하고 모델들의 성능을 비교하였다. 모델 성능 비교 결과 생산성에 기반 하여 소프트웨어 규모로부터 개발기간을 추정하는 모델이 단순하면서도 가장 좋은 결과를 얻었다. 본 모델은 사업 초기에 프로젝트 관리자에게 소프트웨어 개발 기간 의사결정 정보를 제공한다.

• Industrial Engineering and Management Systems
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• 제10권3호
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• pp.197-202
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• 2011

In traditional production lines, such as assembly lines, each worker is usually assigned to a particular fixed work, and decreasing the task to master the assigned work is valuated. However, when an imbalance exists between workers' speeds, if a worker delays the overall work in the production line, the production rate of the particular line will also decrease. To avoid this problem, the "Self-Balancing Production Line" was introduced. In this type of production line, each worker is assigned work dynamically, and when specific conditions are satisfied, production remains balanced. Characteristics of these lines that can be preempted at any place have already been analyzed by some researchers. A previous paper examined the situation in which only a single worker can process one machine and cannot preempt processing, and the improved policy of an ordinary selfbalancing production line, which specifies which stations workers can process and how workers can behave. This policy achieveda high production rate with only four stations and two workers (Buzacott, 2002). In that paper, worker processing stations and the behavior of a specific worker were limited, andthe paper focused only on specific stations and workers. Therefore, it is not applicable to any worker sequence. In this paper, we focus on other ways to decrease cycle time. In this kind of line, a worker processes at his or her speed. Therefore, if a worker is assigned stations according to his or her speed, the line can decrease cycle time. To do so, we relax the assumptions of this type of line and set a new condition. Under these conditions, we compare our results to the results of previous papers.

• 대한치과보철학회지
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• 제44권4호
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• pp.383-393
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• 2006

Statement of problem : Limited research on flowable resin has been undertaken on its application directly on dentin associated with the adhesive systems. Purpose : This study was to evaluate the shear bond strengh and fracture aspect of flowable resin on human dentin with various types of dentin bonding adhesives with thermo cycling effect. Materials and methods: Filtek-Flow(3M ESPE, USA) was used as flowable resin and Eighty human molars were randomly divided into 4 groups : three dentin bonding adhesives (Scotchbond-Multipurpose : 3-step contentional system, One-Step : One-bottle system. Prompt L-Pop : All-in-one, self-etching primer) and 32% etching treatment without bonding adhesive as a control group. For evaluating their durability of bonding, each group was subdivided : storaging in the water at 37$^{\circ}C$(24 hours) and thermocycling (0$^{\circ}C$-55$^{\circ}C$, 30 seconds intervals, 1000 cycle). Shear bond strength tests were performed and resin-dentin interface and fracture mode were observed. Results were analysed by one-way ANOVA and Scheffe's multiple range test. Results and Conclusion : 1. At 0 cycle, the mean shear bond strength of One-Step exhibited the highest value of all groups(p<0.05), and there were no significant differences between Prompt L-Pop and Scotchbond-Multipurpose, Scotchbond-Multipurpose and control(p>0.05). After 1000 thermocycling, One-Step exhibited higher value than other groups(p<0.05), and there were no significant differences among other groups (p>0.05). 2. The shear bond strength of each group was significantly decreased after thermocycling except Scotchbond-Multipurpose (p>0.05). 3. The most common failure mode was adhesive type and mixed type, next in order.

• Asian-Australasian Journal of Animal Sciences
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• 제16권7호
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• pp.1071-1086
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• 2003

Reproductive biotechnologies continue to be developed for genetic improvement of both river and swamp buffalo. Although artificial insemination using frozen semen emerged some decades back, there are still considerable limitations. The major problem appears to be the lack of efficient methods for estrus detection and timely insemination. Controlled breeding experiments in the buffalo had been limited and similar to those applied in cattle. Studies on multiple ovulation and embryo transfer are essentially a replica of those in cattle, however with inherent problems such as lower number of primordial follicles on the buffalo ovary, poor fertility and seasonality of reproduction, lower population of antral follicles at all stages of the estrous cycle, poor endocrine status and a high incidence of deep atresia in ovarian follicles, the response in terms of transferable embryo recovery has remained low with 0.51 to 3.0 per donor and pregnancy rates between 15 to 30%. In vitro production of buffalo embryos is a valid alternative to recovery of embryos by superovulation. This aspect received considerable attention during the past decade, however the proportion of embryos that develops to the blastocyst stage is still around 25-30% and hence the in vitro culture procedures need substantial improvement. Embryo cryopreservation procedures for direct transfer post thaw need to be developed for bubaline embryos. Nuclear transfer and embryo cloning is a technique that has received attention in various species during recent years and can be of immense value in buffaloes as they have a low rate of embryo recoveries by both in vitro and in vivo procedures. Gender pre-selection, genome analysis, gene mapping and gene transfer are a few of the techniques that have been studied to a limited extent during recent years and are likely to be included in future studies on buffaloes. Very recently, reproductive biotechnologies have been applied to feral buffaloes as well, but the results obtained so far are modest. When fully exploited they can play an important role in the preservation of endangered species.

• International Journal of CAD/CAM
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• 제5권1호
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• pp.99-109
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• 2005

This paper introduces an approach to an ontology-based multi-level knowledge framework for a knowledge management system for discrete-product development. Participants in a product life cycle want to share comprehensive product knowledge without any ambiguity and heterogeneity. However, previous knowledge management approaches are limited in providing those aspects: therefore, we suggest an ontology-based multi-level knowledge framework (OBMKF). The bottom level, the axiom, specifies the semantics of concepts and relations of knowledge so ambiguity can be alleviated. The middle level is a product development knowledge map; it defines the concepts and the relations of the product domain knowledge and guides the engineer to process their engineering decisions. The middle level is then classified further into more detailed levels, such as generic product level, specific product level, product version level, and manufactured item level, according to the various viewpoints. The top level is specialized knowledge for a specific domain that gives the solution of a specific task or problem. It is classified into three knowledge types: expert knowledge, engineering function knowledge, and data-analysis-based knowledge. This proposed framework is based on ontology to accommodate a comprehensive range of knowledge and is represented with first-order logic to maintain a uniform representation.

• 한국농촌건축학회논문집
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• 제15권4호
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• pp.9-16
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• 2013

The purpose of this study is presented playground space for early childhood facilities. Describes whether any development of children, and how to respond in accordance with each of the activities. The infants and toddlers life cycle is a continuation of play. Toddlers to play is the essence of life itself, through play, the world embracing and digestive, raising ideas and emotions expressed through play. It is time that paves the growth of infants age children. And equipped with personality, values, emotions, attitudes, play a very important role in this process. Play it delivers, it can not learning education. Sympathetic and experience through play, and be equipped to allow the personality, social, physical. So, we have an obligation required to provide adequate facilities and play so that children can grow properly. In this paper, from the limited play space and is listed on the importance alive to give the children a sense of space to get the sympathetic. And, analysis shown about affect for children each play, and space. In this paper, we performed a study is Performed a case studies of and domestic kindergarten and foreign kindergarten where the differences between the various lists and how to derive a plan for solving the problem by comparison and analysis were performed.

• 한국멀티미디어학회논문지
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• 제21권6호
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• pp.667-677
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• 2018

Since sensor networks consist of sensor nodes with limited energy resources, so efficient energy use of sensor nodes is very important in the design of sensor networks. Sensor nodes consume a lot of energy for data transmission. Clustering technique is used to efficiently use energy in data transmission. Recently, mobile sink techniques have been proposed to reduce the energy load concentrated on the cluster header near a sink node. The CMS(Cluster-based Mobile sink) technique minimizes the generation of control messages by creating a data transmission path while creating clusters, and supports the inter-cluster one-hop transmission. But, there is a case where there is no connectivity between neighbor clusters, it causes a problem of having a long hop data transmission path regardless of local distance. In this paper, we propose a SCBC(Strong connection balancing cluster) to support the path of the minimum number of hops. The proposed scheme minimizes the number of hops in the data transmission path and supports efficient use of energy in the cluster header. This also minimizes a number of hops in data transmission paths even when the sink moves and establishes a new path, and it supports the effect of extending the life cycle of the entire sensor network.

• IEIE Transactions on Smart Processing and Computing
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• 제6권1호
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• pp.27-38
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• 2017

Packet classification is one of the essential functionalities of Internet routers in providing quality of service. Since the arrival rate of input packets can be tens-of-millions per second, wire-speed packet classification has become one of the most challenging tasks. While traditional packet classification only reports a single matching result, new network applications require multiple matching results. Ternary content-addressable memory (TCAM) has been adopted to solve the multi-match classification problem due to its ability to perform fast parallel matching. However, TCAM has a fundamental issue: high power dissipation. Since TCAM is designed for a single match, the applicability of TCAM to multi-match classification is limited. In this paper, we propose a cost- and energy-efficient multi-match classification architecture that combines TCAM with a tuple space search algorithm. The proposed solution uses two small TCAM modules and requires a single-cycle TCAM lookup, two SRAM accesses, and several Bloom filter query cycles for multi-match classifications.

• International Journal of Computer Science & Network Security
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• 제23권8호
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• pp.199-203
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• 2023

Influential trend that widely reflected the software engineering industry is service oriented architecture. Vendors are migrating towards cloud environment to benefit their organization. Companies usually offer products and services with a goal to solve problems at customer end. Because customers are more interested in solution of their problem rather than focusing on products or services. In software industry the approach in which customers' problems are solved by providing services is known as software as a service. However, software development life cycle encounters enormous changes when migrating software from product model to service model. Enough research has been done on the overall development process but a limited work has been done on the factors that influence requirements elicitation process. This paper focuses on those changes that influence requirement elicitation process and proposes a systematic methodology for transformation of software from product to service model in a successful manner. The paper then elaborates the benefits that inherently come along with elicitation process in cloud environment. The paper also describes the problems during transformation. The paper concludes that requirement engineering process turn out to be more profitable after transformation of traditional software from product to service model.