• Journal of the Korean Society for Railway
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• v.5 no.2
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• pp.77-83
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• 2002

In this paper we present a nonlinear programming model for the train seat capacity distribution with a numerical example. The model finds the optimal capacity distribution methods which minimize the sum of the differences between the demands and the seat capacities. Also the model provides the information on the degree of the discrepancy between the demand and the seat capacities. One can use the model as a tool for planning train seat capacity planning.

• Journal of Korean Society of Transportation
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• v.22 no.2 s.73
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• pp.121-130
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• 2004

In these days, multiple-path generation method is highly demanded in practice and research areas, which can represents realistically travelers behavior in choosing possible alternative paths. The multiple-path generation algorithm is one of the key components for policy analysis related to ATIS, DRGS and ATMS in ITS. This study suggested a method to generate multiple Possible paths from an origin to a destination. The approach of the suggested method is different from an other existing methods(K-shortest path algorithm) such as link elimination approach, link penalty approach and simulation approach. The result of the multi-label vine-building shortest path algorithm(MVA) by Kim (1998) and Kim(2001) was used to generate multiple reasonable possible paths with the concept of the rational upper boundary. Because the MVA algorithm records the cost, back-node and back-back node of the minimum path from the origin to the concerned node(intersection) for each direction to the node, many potential possible paths can be generated by tracing back. Among such large number of the potential possible paths, the algorithm distinguishes reasonable alternative paths from the unrealistic potential possible paths by using the concept of the rational upper boundary. The study also shows the very simple network examples to help the concept of the suggested path generation algorithm.

• Journal of Korean Academy of Nursing
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• v.19 no.2
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• pp.173-190
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• 1989

This literature review was undertaken to explore theoretical models of depression for their potential usefulness in nursing research and practice. Depression has bean accounted for by numerous theories or models of causation ; 11 theories selected from psychology, medicine and psychoanalysis and supported by empirical or experimental research were reviewed. These theories identify a variety of precipitating and predisposing factors that may affect the individual's depression. Aggression - turned - inward theory, object loss theory, ego functioning theory, personality organization theory, behavioral theory, learned helplessness theory, cognitive theory, genetic factors, and biological theories conceptualize predisposing factors. Only life stressors theory identifies precipitating facotrs. Each of these theories contributes to an understanding of depression, but many of them use overlapping and interrelated factors. It is also evident from recent. research that there are multiple causes for depression involving an interactive effect among predisposing and precipitating factors that are both biological and psychological in origin. That is, a single theory is not useful, but perhaps a unified theory could be developed that would be helpful to nursing. This review points to the need for continuing development and testing of theories that would integrate the multiple conceptualizations of depression.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.1
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• pp.5-11
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• 2010

An adaptive formation control approach is proposed for nonhonolomic multiple mobile robots considering unknown slipping and skidding. It is assumed that unknown slipping and skidding effects are bounded by unknown constants. Under this assumption, the adaptive technique is employed to estimate the bounds of unknown slipping and skidding effects of each mobile robot. To deal with the skidding effect included in kinematics, the dynamic surface design approach is applied to design a local controller for each mobile robot. Using Lyapunov stability theorem, the adaptation laws for tuning bounds of slipping and skidding are induced and it is proved that all signals of the closed-loop system are bounded and the tracking errors and the synchronization errors of the path parameters converge to an adjustable neighborhood of the origin. Finally, simulation results are provided to verify the effectiveness of the proposed approach.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1352-1357
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• 2004

Thermal error compensation has been developed for CNC (Computer Numerical Control) machining center with moving heat sources. The thermal error in CNC machining center has an effect on machining accuracy more than the geometric error does. Thus, temperature distributions of a spindle unit have been analyzed numerically by a Finite Differential Method and experimentally by an infrared (IR) camera in this study. A multiple variable method has been derived to estimate the thermal deformation of the machine origin stably and effectively after measuring deformation and temperature data. The experimental results for a vertical machining center have shown that the thermal errors of the machine origins were reduced more than 30% by the developed method.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.144.1-144.1
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• 2012

A number of recent observations have established that many globular clusters have double or multiple stellar populations. In particular, recent Calcium and Stromgren b & photometry shows a split in the RGB of some of these globular clusters, including M22, NGC 1851, and NGC 288. However, the origin of this split in the RGB is still controversial. In order to confirm the real difference in Calcium abundance between the two RGBs, we have performed low resolution spectroscopy for RGB stars in these globular clusters. The spectral data were obtained from WFCCD/duPont 2.5m telescope in Las Campanas Observatory. We found a significant bimodality of both Calcium and CN abundances in M22 and NGC 1851. NGC 288, however, shows a clear bimodality only in CN abundance.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.299-319
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• 1997

Since a convergence strategy in interactive procedure is the origin of a lot of the restrictions and inconvenience of many methods, a new flexible convergence strategy is necessary for developing that is applicable for interactive MOLP as well as interactive multiple objective integer programming(MOIP). A method for computing the volume of the interval defined subsets of weighting vector space is developed using Sobol's LP$_{i}$, Generator. Since the interactive procedure requires a number of iterations, with a fixed number of solutions presented per iteration, a convergence strategy is needed to control the rate at which the interactive procedure converges to a final solution. Thus, in this paper, a new convergency strategy is developed.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.165-172
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• 1987

An expression vector in a mammalian cell was constructed using the origin of replication (OR) and the promoters of SV40. The plasmid pSVOE was constructed by inserting SV40 DNA fragment (1, 118bp) containing SV40 OR and promoters into pBR322-1, and then a multiple cloning sequence was inserted at the immediate downstream of the late promoter of SV40 in the pSVOE vector. The plasmid was named pSVML. As a selection marker, thymidine kinase gene of herpes simplex virus with its promoter was inserted into EcoRI site of pSVML and the recombinant was named pSVML-TKp. To test the expression capacity of foreigen gene inserted at the multiple cloning site of pSVML, the thymidine kinase gene without its own promoter was inserted at the BamHI site of pSVML. The recombinant was named pSVML-TK. These plasmids, pSVML-TKp and pSVML-TK, were transfected into COS cells with calcium phosphate precipitation method. The thymidine kinase activity was significantly increased in both transfected cells.

• Korean Journal of Head & Neck Oncology
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• v.13 no.1
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• pp.58-61
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• 1997

Multiple primary cancer is defined as the discrete primary cancers in an individual originating in different sites or tissues. Billroth, in 1869, first reported the occurrence of different primary malignant cancers in the same patient. Because early diagnosis and treatment are key to good survival and cure rates, clinicians should be more aware of the possibility of multiple primary cancers in an individual patient with malignant tumor. The authors recently experienced a case of fifth primary cancer, their sites of origin were lung, glottis, lymph node, supraglottis, common bile duct. We report this case with a brief review of literatures.

• Honam Mathematical Journal
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• v.40 no.4
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• pp.785-794
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• 2018

In [8] they introduced a new finite element method for accurate numerical solutions of Poisson equations with corner singularities. They consider the Poisson equations with homogeneous Dirichlet boundary condition with one corner singularity at the origin, and compute the finite element solution using standard FEM and use the extraction formula to compute the stress intensity factor, then pose a PDE with a regular solution by imposing the nonhomogeneous boundary condition using the computed stress intensity factor, which converges with optimal speed. From the solution they could get an accurate solution just by adding the singular part. This approach uses the polar coordinate and the cut-off function to control the singularity and the boundary condition. In this paper we consider Poisson equations with multiple singular points, which involves different cut-off functions which might overlaps together and shows the way of cording in FreeFEM++ to control the singular functions and cut-off functions with numerical experiments.