• 산업경영시스템학회지
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• 제26권4호
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• pp.63-71
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• 2003

This paper analyses a deterministic scheduling problem concerned with manufacturing multiple types of components at a pre-assembly stage composed of parallel fabrication machines. Each component part is machined on a fabrication machine specified in advance. The manufactured components are subsequently assembled into products. The completion time of a job(product) is measured by the latest completion time of its all components at the pre-assembly stage. The problem has the objective measure of minimizing the total weighted completion time of a finite number of jobs. Two lower bounds are derived and tested in a branch-and-bound scheme. Also, three constructive heuristic algorithms are developed based on the machine aggregation and greedy strategies. Some empirical evaluation of the performance of the proposed branch-and-bound and heuristic algorithms are also performed.

• 한국주거학회논문집
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• 제22권2호
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• pp.43-51
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• 2011

This study aims to analyze the on-site improvement area of residential environment improvement project based on research results derived from the on-site and questionnaire survey in case of Daegu. The main findings are as follows. First, residents complain about delay of project completion because a long time has been passed after on-site improvement area was designated. Experts and government officials agree that a new method of development is required. Second, future development should discriminate on-site improvement area according to its level of project completion. The area should be classified into project completion areas and on-going area, and new methods, such as redevelopment, apartment-housing construction method, should be allowed. Third, for better management of on-site improvement area, laws and regulations must be ready and government's will for improvement is crucial.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2015년도 추계학술대회
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• pp.4-7
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• 2015

In this paper, we propose a matrix completion algorithm for Internet of Things (IoT) localization. The proposed algorithm recovers the Gram matrix of sensors by performing optimization over the Riemannian manifold of fixed-rank positive semidefinite matrices. We compute and show the closed forms of all the differentially geometric components required for applying nonlinear conjugate gradients combined with Armijo line search method. The numerical experiments show that the performance of the proposed algorithm in solving IoT localization is outstanding compared with the state-of-the-art matrix completion algorithms both in noise and noiseless scenarios.

• 한국정보처리학회논문지
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• 제6권5호
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• pp.1203-1211
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• 1999

Checkpointing is the one of fault-tolerant techniques to restore faults and to restart job fast. Checkpointing algorithms in distributed systems have been studied for many years. These algorithms can be classified into synchronous Checkpointing algorithms and asynchronous Checkpoiting algorithms. In this paper, we propose an independent Checkpointing algorithm that has a minimum Checkpointing counts equal to periodic Checkpointing algorithm, and relatively short rollback distance at faulty situation. Checkpointing count is directly related to task completion time in a fault-free situation and short rollback distance is directly related to task completion time in a faulty situation. The proposed algorithm is compared with the previously proposed asynchronous Checkpointing algorithms using simulation. In the simulation, the proposed Checkpointing algorithm produces better results than other algorithms in terms of task completion time in fault-free as well as faulty situations.

• 한국안전학회지
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• 제22권6호
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• pp.55-62
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• 2007

The structural safety of long span bridges such as suspension bridges is smaller under the construction stage than in the completion. But the importance of construction sequences has been neglected in most of safety check programs. On this study is developed the structural analysis method of suspension bridges considering construction sequences and structural analyses are performed by step by step during construction. This can be used to determine the safest erection method. The results shows that the more critical structural behavior appears under construction than after completion.

• Kyungpook Mathematical Journal
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• 제45권4호
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• pp.481-489
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• 2005

We first show that any complete MV-algebra whose Boolean subalgebra of idempotent elements is atomic, called a complete MV-algebra with atomic center, is isomorphic to a product of unit interval MV-algebra 1's and finite linearly ordered MV-algebras of A(m)-type $(m{\in}{\mathbb{Z}}^+)$. Secondly, for a semi-simple MV-algebra A, we introduce a completion ${\delta}(A)$ of A which is a complete, MV-algebra with atomic center. Under their intrinsic topologies $(see\;{\S}3)$ A is densely embedded into ${\delta}(A)$. Moreover, ${\delta}(A)$ has the extension universal property so that complete MV-algebras with atomic centers are epireflective in semi-simple MV-algebras

• 대한수학회지
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• 제58권6호
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• pp.1311-1325
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• 2021

One says that a ring homomorphism R → S is Ohm-Rush if extension commutes with arbitrary intersection of ideals, or equivalently if for any element f ∈ S, there is a unique smallest ideal of R whose extension to S contains f, called the content of f. For Noetherian local rings, we analyze whether the completion map is Ohm-Rush. We show that the answer is typically 'yes' in dimension one, but 'no' in higher dimension, and in any case it coincides with the content map having good algebraic properties. We then analyze the question of when the Ohm-Rush property globalizes in faithfully flat modules and algebras over a 1-dimensional Noetherian domain, culminating both in a positive result and a counterexample. Finally, we introduce a notion that we show is strictly between the Ohm-Rush property and the weak content algebra property.

• 대한임베디드공학회논문지
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• 제14권2호
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• pp.63-69
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• 2019

Recently, ultra-low latency flash storage devices such as Z-SSD and Optane SSD were introduced with the significant technological improvement in the storage devices which provide much faster response time than today's other NVMe SSDs. With such ultra-low latency, $10{\mu}s$, storage devices the cost of context switch could be an overhead during interrupt-driven I/O completion process. As an interrupt-driven I/O completion process could bring an interrupt handling overhead, polling or hybrid-polling for the I/O completion is known to perform better. In this paper, we analyze tail latency problem in a polling process caused by process scheduling in data center environment where multiple applications run simultaneously under one system and we introduce our adaptive polling selection technique which dynamically selects efficient processing method between two techniques according to the system's conditions.

• Kyungpook Mathematical Journal
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• 제58권4호
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• pp.711-732
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• 2018

In this paper, we give a new approach to solving the 2-variable subnormal completion problem (SCP for short). To this aim, we extend the notion of recursively generated weighted shifts, introduced by R. Curto and L. Fialkow, to 2-variable case. We next provide "concrete" necessary and sufficient conditions for the existence of solutions to the 2-variable SCP with minimal Berger measure. Furthermore, a short alternative proof to the propagation phenomena, for the subnormal weighted shifts in 2-variable, is given.

• 대한지리학회지
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• 제42권4호
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• pp.648-665
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• 2007

현재의 공통사회(지리)교육전공 및 지리교육전공 학과의 교육과정은 교육부가 발행한 교원자격 실무편람 상의 기본이수과목만 제시하고 있고, 기본이수과목별 주요주제는 설정하고 있지 않다는 문제점을 지니고 있다. 이러한 기본이수과목별 주요주제의 미 설정 상태는 공통사회(지리)교육전공 및 지리교육전공 학과의 표준교육과정의 부재상태로 연결되고 있고, 급기야 해당 중등교사 임용시험의 출제와 응시에 많은 애로를 야기하고 있다. 이에, 본 연구에서는 우선 공통사회(지리) 및 지리의 21개 기본이수과목들을 대상으로 주요주제를 설정하였다. 이러한 '공통사회(지리) 및 지리의 기본이수과목별 주요주제'는 '공통사회(지리)교육전공 및 지리교육전공 학과의 표준교육과정의 내용요소'와 '공통사회(지리) 및 지리의 중등교사 임용시험의 평가요소'를 설정하는데 기반이 될 것이다. 특히, 기본이수과목별 주요주제 설정'과 '표준교육과정 작성'은 교육부가 2009년 동시시행 예정으로 추진하고 있는 '사범대학 교육과정 개편'과 '중등교사 임용시험 제도 개편'을 감안하면, 시의적절한 일이다. 그러나, 본 연구에서 설정된 '공통사회(지리) 및 지리의 기본이수과목별 주요주제'는 사정상 짧은 시간에 이루어진 것이므로 재 연구되어야 한다. 기타, 표시과목 지리의 기본이수과목은 구성 자체에 많은 문제점들을 내포하고 있으므로 반드시 개정되어야 한다.