• Journal of the military operations research society of Korea
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• v.32 no.1
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• pp.113-132
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• 2006

This study suggested a readily applicable model to estimate the proper purchasing amount and the optimal CSP(Concurrent Spare Parts) inventory level based on a supporting echelon. For this model to be implemented, it is determined for studies about Multi-echelon Inventory Model to be divided by issues and utilized in the system Moreover, the model also includes the factors that are to be excluded for a reasearch purpose and to be simply assumed. Compared to previous studies, this model is to be considered the most possible factors, realistically designed, and practically used. It is claimed that the results of this model would raise an issue of improving traditional approaches in CSP acquisition and inventory management.

• Journal of the military operations research society of Korea
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• v.23 no.1
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• pp.63-75
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• 1997

This study is concerned with a few models for optimal requirement level of CSP by improving and adjusting the existing models to determine CSP items and quantity as follows. First, by building a model with a objective function of the operating level and constrains of budget, quantity and items of CSP are simultaneously determined. Second, we removed some steps to improve initial solution by using a constraint of usable budget level. Third, we demonstrated a model to be applied with real operating situation by combining two models of Lee(1994) and above. Lastly, by assuming a failure probability distribution is a binomial distribution, the better solution can be obtained. Some facts with necessity of policy improvement were raised as follows: (1) necessity of improvement of the CSP acquisition system, (2) in case of the same kind, permission of diversion in order to execute budget effectively, (3) getting accurate failure rate.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.1
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• pp.87-94
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• 2007

Many researchers have modeled complicated problems with distributed AI technologies in distributed environment. Especially, intelligent agent technology we often proposed among researchers as efficient method to solve the complicated problems because agent technology makes possibile to share different problem solving abilities among processors in distributed processing environment. In this paper, we propose multiagent system model to solve distributed scheduling problem. At this point we apple CSP techniques to the multiagent model as individual problem solving ability of member agents. Scheduling problem is divided into subproblems according to constraints by distributed resources, then each agent solves its subproblem using CSP solver in the proposed model. This method improves scheduling efficiency. For meeting scheduling problem of case study, we show CSP modeling process and suggest problem solving procedure by multiagent system model.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.11
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• pp.1022-1028
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• 2013

It is well knowns that based on the CSP (Common Spatial Pattern) algorithm, the linear projection of an EEG (Electroencephalography) signal can be made to spaces that optimize the discriminant between two patterns. Sharing disadvantages from linear time invariant systems, CSP suffers from the non-stationary nature of EEGs causing the performance of the classification in a BCI (Brain-Computer Interface) system to drop significantly when comparing the training data and test data. The author has suggested a simple idea based on the parallel model of CSP filters to improve the performance of BCI systems. The model was tested with a simple CSP algorithm (without any elaborate regularizing methods) and a perceptron learning algorithm as a classifier to determine the improvement of the system. The simulation showed that the parallel model could improve classification performance by over 10% compared to conventional CSP methods.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.1
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• pp.51-58
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• 2006

The objective of this research work is to investigate into heat transfer characteristics of the laser cutting of CSP 1N sheet using high power CW Nd:YAG laser. In order to investigate the heat transfer characteristics, three dimensional quasi stationary and steady-state heat transfer analysis has been carried out. The laser heat source is assumed as a volumetric heat source with a gaussian heat distribution in a plane. Through the comparison of the results of analyses with those of experiments, the proper finite element model has been obtained. In addition, characteristics of the three-dimensional heat transfer and temperature distribution have been estimated by the finite element model. Finally, the minimum temperature at the center for cutting of the material has been estimated.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.41
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• pp.123-134
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• 1997

In this paper we consider the CSP requirements determination problem of new equipment system. The CSP we deal with in the paper are restricted to the demand-based spare parts. For the newly procured equipment systems, mathematical analyses are made for the system which is constructed with the repairable items to derive the associated CSP requirement determination model in mathematical expression, respectively. Based on these analyses, a mathematical model is derived for making an optimal CSP requirement determination subject to the constraint of satisfying any given funds limitation. We assume that the failure of a part follows a Poisson process. Firstly, the operational availability concept in CSP is defined and the relation between the general system availability and the operational availability is established. Secondly, the problem is formulated as the operational availability maximization problem that should satisfy the funds limitation, and then, using the generalized Lagrange multipliers method, the optimal solution procedure is derived.

• Industrial Engineering and Management Systems
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• v.16 no.1
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• pp.52-63
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• 2017

The inventory level of concurrent spare parts (CSP) has a significant impact on the availability of a weapon system. A failure rate function might be of particular importance in deciding the CSP inventory level. We developed a CSP optimization model which provides a compromise between purchase costs and shortage costs on the basis of the Weibull and the exponential failure rate functions, assuming that a failure occurs according to the (non-) homogeneous Poisson process. Computational experiments using the data obtained from the Korean Navy identified that, throughout the initial provisioning period, the optimization model using the exponential failure rate tended to overestimate the optimal CSP level, leading to higher purchase costs than the one using the Weibull failure rate. A Pareto optimality was conducted to find an optimal combination of these two failure rate functions as input parameters to the model, and this provides a practical solution for logistics managers.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.299-306
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• 2001

Crushed Stone Pile(CSP) is one of the ground improvement methods available to loose sand and clayey ground by forming compacted CSP in the weak soil layer. The effects of this method are enhancement of ground bearing capacity, reduction of settlement and prevention of lateral ground movement in cohesive layer, reduction of liquefaction potential in sandy ground. This study performs model tests in 1.0m${\times}$1.0m${\times}$1.0m and 1.5m${\times}$1.5m${\times}$l.2m model tank to observe bearing capacity of CSP treated ground. The area replacement ratio of CSP composite ground varies 20%, 30% and 40% with square grid pattern. After the composite ground was consolidated under pressure of 0.5kg/$\textrm{cm}^2$ and 1.0kg/$\textrm{cm}^2$, load tests were carried out. The results show that ultimate bearing capacity increases with area replacement ratio and the preconsolidation pressure of ground.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2508-2512
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• 2012

Cold shock proteins (CSPs) are a family of proteins induced at low temperatures. CSPs bind to single-stranded nucleic acids through the ribonucleoprotein 1 and 2 (RNP 1 and 2) binding motifs. CSPs play an essential role in cold adaptation by regulating transcription and translation via molecular chaperones. The solution nuclear magnetic resonance (NMR) or X-ray crystal structures of several CSPs from various microorganisms have been determined, but structural characteristics of psychrophilic CSPs have not been studied. Therefore, we optimized the purification process to obtain highly pure Lm-Csp and determined the three-dimensional structure model of Lm-Csp by comparative homology modeling using MODELLER on the basis of the solution NMR structure of Bs-CspB. Lm-Csp consists of a ${\beta}$-barrel structure, which includes antiparallel ${\beta}$ strands (G4-N10, F15-I18, V26-H29, A46-D50, and P58-Q64). The template protein, Bs-CspB, shares a similar ${\beta}$ sheet structure and an identical chain fold to Lm-Csp. However, the sheets in Lm-Csp were much shorter than those of Bs-CspB. The Lm-Csp side chains, E2 and R20 form a salt bridge, thus, stabilizing the Lm-Csp structure. To evaluate the contribution of this ionic interaction as well as that of the hydrophobic patch on protein stability, we investigated the secondary structures of wild type and mutant protein (W8, F15, and R20) of Lm-Csp using circular dichroism (CD) spectroscopy. The results showed that solvent-exposed aromatic side chains as well as residues participating in ionic interactions are very important for structural stability. Further studies on the three-dimensional structure and dynamics of Lm-Csp using NMR spectroscopy are required.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.48
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• pp.113-122
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• 1998

In this paper we consider the CSP requirements determination problem of new equipment(machine) system. For the newly procured equipment systems, mathematical analyses are made for the system which is constructed with the consumable parts to derive the associated CSP requirement determination model in mathematical expression. Based on these analyses, a mathematical model is derived for making an optimal CSP requirement determination subject to tile constraint of satisfying any given operational availability limitation. We assume that the failure of a part follows a Poisson process. Firstly, the operational availability concept in CSP is defined and the relation between the general system availability and the operational availability is established. Secondly, the problem is formulated as the cost minimization problem that should satisfy the operational availability limitation, and then, using the generalized Lagrange multipliers method, the optimal solution procedure is derived.