• Title/Summary/Keyword: Operations and States

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Structural effects on stock price forecasting

  • Kim, Steven H.;Kang, Dae-Suk
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 1996년도 추계학술대회발표논문집; 고려대학교, 서울; 26 Oct. 1996
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    • pp.207-210
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    • 1996
  • Learning methodologies such as neural networks or genetic algorithms usually require long training times. Case based reasoning, however, attains peak performance swiftly and is often appropriate for learning even with small data sets. Previous work has shown that an extended case reasoning methodology can yield superior performance in the task of predicting financial data series. This paper examines the impact of reasoning procedures on stock price prediction. The following characteristics are evaluated: size of input vector, multiplicity of neighboring states, and a scaling factor for growth. The concepts are illustrated in the context of predicting the price of an individual price.

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성과기반군수(PBL)를 활용한 군수지원 발전방안 연구 (A Study on the Improvement of Logistic Support by Performance Based Logistics)

  • 최석철
    • 한국국방경영분석학회지
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    • 제34권2호
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    • pp.43-61
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    • 2008
  • 성과기반군수는 전투준비태세를 향상시키고 무기체계의 수법주기비용을 절감하기 위하여 연구되었다. 최근 미국 국방부는 성과기반군수를 연구하고 발전시켜서 이것을 미국 군수분야에 적용하고 있다. 따라서 본 연구논문에서는 미국의 군수기원 분야의 발전동향을 살펴보고 우리나라의 군수지원 분야의 실태를 분석한 후, 효율적인 군수지원을 위하여 성과기반군수를 활용한 군수지원 발전방안을 제시하였다.

Dynamic Load Balancing and Network Adaptive Virtual Storage Service for Mobile Appliances

  • Ong, Ivy;Lim, Hyo-Taek
    • Journal of Information Processing Systems
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    • 제7권1호
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    • pp.53-62
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    • 2011
  • With the steady growth of mobile technology and applications, demand for more storage in mobile devices has also increased. A lightweight block-level protocol, Internet Advanced Technology Attachment (iATA), has been developed to deliver a cost-effective storage network solution for mobile devices to obtain more storage. This paper seeks to contribute to designing and implementing Load Balancing (LB), Network Monitoring (NM) and Write Replication (WR) modules to improve the protocol's scalability and data availability. LB and NM modules are invoked to collect system resources states and current network status at each associate node (server machine). A dynamic weight factor is calculated based on the collected information and sent to a referral server. The referral server is responsible to analyze and allocate the most ideal node with the least weight to serve the client. With this approach, the client can avoid connecting to a heavily loaded node that may cause delays in subsequent in-band I/O operations. Write replication is applied to the remaining nodes through a WR module by utilizing the Unison file synchronization program. A client initially connected to node IP A for write operations will have no hindrances in executing the relevant read operations at node IP B in new connections. In the worst case scenario of a node crashing, data remain recoverable from other functioning nodes. We have conducted several benchmark tests and our results are evaluated and verified in a later section.

ACHIEVING CONSISTENCY IN LIGHTING SCHEMES FOR CONSTRUCTION WORK ZONES THROUGH LIGHTING SIMULATION

  • Khaled Nassar;Soo-Young Kim
    • 국제학술발표논문집
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    • The 2th International Conference on Construction Engineering and Project Management
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    • pp.269-278
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    • 2007
  • Nighttime construction is being adopted by many state DOT's as a way to mitigate the impact of construction operations on the traveling public. Although a number of states have developed standard specifications for nighttime lighting, these standards are usually in the form of generic requirement statements that only specify minimum illuminance levels. The lighting standards do not include specific ways to achieve this illuminance level such as lighting arrangements and configurations for various work zone plans and construction operations. This leaves confusion between the traffic engineers and the contractors and does not guarantee consistency in those plans, thus affecting productivity and safety (lighting conditions account for 18% to 28% of work zone accidents). The main objective of this study is to utilize three dimensional animation and lighting analysis software to study and model lighting conditions of a construction site. This is expected to increase the safety and productivity of construction operations by achieving consistency in work zone lighting schemes. A computerized model was developed, called Nitelite. Various lighting schemes can be studied using the software to provide for typical applications including lighting fixture's locations, luminance, mounting height, tilt angle, and fixture type. The results from the developed software tool were validated through comparisons with previous research conducted using field measurements.

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Using Reliability Tools to Characterize Wood Strand Thickness of Oriented Strand Board Panels

  • Chastain, J.S.;Young, T.M.;Guess, F.M.;Leo, R.V.
    • International Journal of Reliability and Applications
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    • 제10권2호
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    • pp.89-99
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    • 2009
  • Oriented Strand Board (OSB) is an important engineered wood product used in housing construction which has a lower environmental impact or "carbon footprint." In this paper, reliability and statistical tools are applied to gain insights on the strand thickness of OSB panels. An OSB panel consists of several hundred wood strands that are resinated and pressed. The variability of OSB strand thickness for six manufacturers in the Eastern United States is examined as a whole, as well as individually. Little research exists on OSB strand thickness across mills even though strand thickness variability has been documented in laboratory experiments to greatly influence the dimensional stability of OSB panels. Our aims are to quantify and characterize strand thickness, plus apply reliability techniques, such as Kaplan-Meier curves, to characterize the probability of strand thickness. We further explore graphically and statistically the thickness of the strands.

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수명의 불확실성을 반영한 추계학적 장비 대체시기 결정모형 (A Stochastic Optimization Model for Equipment Replacement Considering Life Uncertainty)

  • 박종인;김승권
    • 한국국방경영분석학회지
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    • 제29권2호
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    • pp.100-110
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    • 2003
  • Equipment replacement policy may not be defined with certainty, because physical states of any technological system may not be determined with foresight. This paper presents Markov Decision Process(MDP) model for army equipment which is subject to the uncertainty of deterioration and ultimately to failure. The components of the MDP model is defined as follows: ⅰ) state is identified as the age of the equipment, ⅱ) actions are classified as 'keep' and 'replace', ⅲ) cost is defined as the expected cost per unit time associated with 'keep' and 'replace' actions, ⅳ) transition probability is derived from Weibull distribution. Using the MDP model, we can determine the optimal replacement policy for an army equipment replacement problem.

다수의 동일한 입력원을 갖는 ATM Multiplexer의 정확한 셀 손실 확률 분석

  • Choi, Woo-Yong;Jun, Chi-Hyuck
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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    • pp.435-444
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    • 1995
  • We propose a new approach to the calculation of the exact cells loss probability in a shared buffer ATM multiplexer, which is loaded with homogeneous discrete-time ON-OFF sources. Renewal cycles are identified in regard to the state of input sources and the buffer state on each renewal circle is modelled as a K(shared buffer size)-state Markov chain. We also analyze the behavior of queue build-up at the shared buffer whose distribution together with the steady-state probabilities of the Markov chain leads to the exact cell loss probability. Our approach to obtaining the exact cell loss probability seems to be more efficient than most of other existing ones since our underlying Markov chain has less number of states.

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An Improving Method of Restructuring Parallel Programs for Data Race Detection

  • Ha, Keum-Sook;Lee, Sung woo;Yoo, Kee-Young
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -2
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    • pp.715-718
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    • 2000
  • Although shared memory parallel programs are designed to be deterministic both in their final results and intermediate states, the races that occur when different processes access a common memory location in an order not guaranteed by synchronization could result in unintended non-deterministic executions of the program. So, Detecting races, particularly first data races, is important for debugging explicit shared memory parallel programs. It is possible that all data races reported by other on-the-fly algorithms would disappear once the first races were removed. To detect races parallel programs with nested loops and inter-thread coordination, it must guarantee the order of synchronization operations in an execution instance. In this paper, we propose an improved restructuring method that guarantee ordering execution instance and preserve the semantics of original program. This method requires O(np) time and (s + up) space, where n is the number of total operations, s is the number of synchronization operations and p is the number of parallelism in the execution. Also, this method makes on-the-fly detection of parallel program with nested loops and inter-thread coordination more easily in space and time complexity.

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국내기업의 경영품질 평가사례 연구 (A CASE STUDY ON THE MANAGEMENT QUALITY KOREAN COMPANIES)

  • 서정일;이영훈;유명관
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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    • pp.494-499
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    • 2004
  • 본 연구는 경영품질의 일반적인 평가 기준인 리더십, 전략기획, 고객과 시장중시, 정보와 분석, 인적자원중시, 프로세스관리, 사업 성과들에 대한 국내 기업의 사례에 대한 연구이다. 국내의 대기업 및 중소기업들 중에서 임의로 선정한 78개 회사에 대하여 평가를 실시하고, 도출된 결과 데이터들을 크기 별로 A, B, C 3개의 그룹으로 구분하여 기업의 순이익과 한국생산성본부에서 주관하는 생산성대상의 경영생산성대상 심사기준에 근거하여 부여한 경영생산성 점수와의 상호 연관 관계 및 기업의 일반적인 성향을 분석하여 한국 기업들의 특성을 고찰한다.

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Existence of a nash equilibrium to differential games with nonlinear constraints

  • Kim, Yang-Yol
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 1989년도 추계학술발표회 발표논문초록집; 이화여자대학교, 서울; 23 Sep. 1989
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    • pp.45-50
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    • 1989
  • The above theorm states that much larger classes of differential games have an equilibrium. The most severe assumption is the second one. It requires that state dynamic equations be linear on his own control variables. But, the dynamic programming approach applied in the above is hardly implementable for the purpose of computation. It is very difficult to solve (SP$_{it}$) directly. Notice, however, the problem can be transformed into a Hamiltonian maximization problem which is easy to solve if initial conditions are given. In this way, it is possible to design a solution algorithm to problems with nonlinear constraints. The above two theorems probide a basis for such an algorithm.m.

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