• 한국산업융합학회 논문집
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• 제5권4호
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• pp.329-337
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• 2002

It is the actual condition that the increasing traffic delay and accident caused by inefficient management on various construction by occupying the roadways. Since almost roadway improvements are for the public convenient, negative effects by them are ignored. But now due to the increase of traffics demand and limitation of road supply, the positive management scheme and treatment plan on the constructions must be considered. Thus, to the extent of this study divides uninterrupted flow into freeways and the Highway, yielding the time spread between under construction and not, that is delay time, we build capacity and delay model in the change of traffic volume and occupying length.

• Radiation Oncology Journal
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• 제13권2호
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• pp.121-128
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• 1995

Purpose: The enhanced cytotoxic effect of combined treatment of hyper-thermia and chemotherapy by increasing intracellular acidity with HMA was investigated. Materials and Methods: FSall tumor cells were injected on the hindlegs of female $C_3H$ mice. When the tumor volume reached about 200mm3, experiments were performed on the groups classified as follows: Group I :Control, Group II : Melphalan alone (2.5mg/kg, 5mg/kg, 10mg/kg, 15mg/kg), Group III : Heat alone $(42.5^{\cdot}C$ for 1 hour) Group IV : Melphalan + Heat $(42.5^{\cdot}C$ for 1 hour), Group V : HMA(10mg/kg) + Melphalan(5.0mg/kg) + Heat$(42.5^{\cdot}C$ for 1hour). Each group included 8-12 mice on each experiment HMA (3-amino-6-chloro-5-(1-homopiperidyl )-N-(diaminomethylene) -c-pyrazinecarboxamide), an analog of amiloride which increases intracellular pH(pHi) was dissolved in dimethyl sulfoxide (DMS) and injected into the tumor-bearing mice through the tail vein. 10mg/kg of HMA and each dose of melphalan were injected into peritoneum of the tumor-bearing mice 30 minutes before heating. Tumor growth delay was calculated when the tumor volme reached at $1500mm^3$ Excision assay was performed on each group and repeated 2-4 times. Results : Tumor growth delay of each experimental groups at $1500mm^3$ were 9, 10, 13 and 19 days respectively. In vivo-in vitro excision assay using FSall tumor cells, the cytotoxicity of each experimental groups was $1.2{\times}10^7,\;1{\times}10^7,\;6{\times}10^6,\;1.7{\times}10^6\;and\;1{\times}10^5$ clonogenic cells/gm respectively When HMA was added to the combined treatment of heat and .chemotherapy, the tumor growth was delayed more than combined treatment without HMA i.e., 6 days tumor growth delay at $1500mm^3$ of tumor volume. Conclusion: The combined effect of cytotoxicity by heat and chemotherapy can be much more enhanced by HMA.

• Journal of Information Technology Applications and Management
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• 제18권4호
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• pp.169-181
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• 2011

The study developed the ideas of innovation resistance attitude in view of innovation delay, rejection, and objection. Authors developed the idea of innovation resistance attitudes of customers in view of innovation diffusion process. The study categorized the idea of resistance such as delay, rejection, and objection. The study hired the structural equation modeling to evaluate the relationships among the consumers' subjective variables such as incongruence, uncertainty, perceived performance, peer usage, and tradition orientation those were factored out by the survey test. These measured variables were analyzed into the innovation resistance related latent variables. The study provides the basic treatment to introduce new technologies and products to the superficially resisting customers. Those resisting customers might be future late adopters. The research results provide the basic arguments for prerequisite treatment to introduce smart phone in the global market place.

• Journal of Trauma and Injury
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• 제23권2호
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• pp.113-118
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• 2010

Purpose: Prolonged stay in the emergency department (ED), which is closely related with the time interval from the ED visit to a decision to admit, might be associated with poor outcomes for trauma patients and with overcrowding of the ED. Therefore, we examined the factors affecting the delay in the decision to admit severe trauma patients. Also, a multidisciplinary department system was preliminarily evaluated to see if it could reduce the time from triage to the admission decision. Methods: A retrospective observational study was conducted at a tertiary care university hospital without a specialized trauma team or specialized trauma surgeons from January 2009 to March 2010. Severe trauma patients with an International Classification of Disease Based Injury Severity Score (ICISS) below 0.9 were included. A multivariable logistic regression analysis was used to find independent variables associated with a delay in the decision for admission which was defined as the time interval between ED arrival and admission decision exceeded 4 hours. We also simulated the time from triage to the decision for admission by a multidisciplinary department system. Results: A total of 89 patients were enrolled. The average time from triage to the admission decision was $5.2{\pm}7.1$ hours and the average length of the ED stay was $9.0{\pm}11.5$ hours. The rate of decision delay for admission was 31.5%. A multivariable regression analysis revealed that multiple trauma (odds ratio [OR]: 30.6, 95%; confidence interval [CI]: 3.18-294.71), emergency operation (OR: 0.55, 95%; CI: 0.01-0.96), and treatment in the Department of Neurosurgery (OR: 0.07, 95%; CI: 0.01-0.78) were significantly associated with the decision delay. In a simulation based on a multidisciplinary department system, the virtual time from triage to admission decision was $2.1{\pm}1.5$ hours. Conclusion: In the ED, patients with severe trauma, multiple trauma was a significant factor causing a delay in the admission decision. On the other hand, emergency operation and treatment in Department of Neurosurgery were negatively associated with the delay. The simulated time from triage to the decision for admission by a multidisciplinary department system was 3 hours shorter than the real one.

• 한국화재소방학회논문지
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• 제24권3호
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• pp.52-57
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• 2010

본 논문에서는 방염에 의한 초가지붕과 목재구조에 대한 화재 예방대책을 고찰하였다. 초가지붕 재료인 볏짚에 함침시간을 달리하여 방염처리를 한 후 물에 침수시켜 세척한 후에도 방염성능을 유지하는지 확인하였다. 목재는 방염처리 방법에 따른 방염효과를 비교분석하기 위하여 상압함침법과 진공가압법, 붓칠 등의 방법으로 방염처리 하였다. 볏짚의 방염성능은 콘 히터를 이용하여 착화지연시간을 측정하였으며 목재의 방염성능은 45도 연소시험과 콘 히터 실험을 통해 실험하였다. 실험 결과 특수 가연물인 볏짚의 경우 방염처리한 볏짚의 착화지연시간이 처리되지 않은 것보다 훨씬 길게 나타났으며 방염처리 후 물에 침수시켜 세척한 경우에도 처리되지 않은 시료에 비하여 착화지연시간이 길게 나타나 방염성능을 유지하는 것으로 나타났다. 목재의 경우 진공가압법으로 방염처리한 시료의 방염효과가 가장 우수하였고 붓칠이나 상압함침한 경우에도 처리하지 않은 것보다 착화지연시간이 길게 나타나 화재 확산 예방에 효과가 있음을 알 수 있었다.

• Journal of applied mathematics & informatics
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• 제29권3_4호
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• pp.955-967
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• 2011

In this paper we have considered a nonautonomous predator-prey model with discrete time delay due to gestation, in which there are two prey habitats linked by isotropic migration. One prey habitat contains a predator and the other (a refuge) does not. Here, we have established some sufficient conditions on the permanence of the system by using in-equality analytical technique. By Lyapunov functional method, we have also obtained some sufficient conditions for global asymptotic stability of this model. We have observed that the per capita migration rate among two prey habitats and the time delay has no effect on the permanence of the system but it has an effect on the global asymptotic stability of this model. The aim of the analysis of this model is to identify the parameters of interest for further study, with a view to informing and assisting policy-maker in targeting prevention and treatment resources for maximum effectiveness.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.85-89
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• 1998

A switching power stage is a very nonlinear system because it has two or more operation modes in one switching cycle. To model a switching power stage, the state space averaging method has been developed. Though it allows a unified treatment of a large variety of switching power stages, the model it yields is always very nonlinear. So, it is required to linearize the averaged model. But it is well known that a controller for a nonlinear plant designed by the linearization frequently fails in showing satisfactory control performance. Hence it is very natural to try to design a nonlinear controller for a switching power stage. In design of a switching power system, nonlinear control approaches such as adaptive control and fuzzy control have been widely studied so far. In this research, a recently developed control method, time delay control is briefly studied and a design example for a ZVS PWM half bridge converter is given. The performance of the time delay controller is compared to its conventional counterpart, PI controller by computer simulations.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.58-58
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• 2001

This paper shows a practical approach that is robust to the errors causing path-delay in mobile wireless location, and analyzes its performance by comparing with other methods. NLOS(non-line-of-sight) error and multipath are two big sources of positioning error in wireless location. Contrary to GPS(global positioning system), they result from the terrestrial propagation of a signal. Especially, since LOS(line-of-sight) path between a transceiver and a receiver is blocked by intermediate buildings and topography, NLOS causes a signal to be reflected and diffracted. This path-delay error is very localized, and so, it is not easy to be estimated and mitigated. To treat such localized error, therefore ...

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권3호
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• pp.146-152
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• 2009

Traditional surgical method or injection using filler is performed for soft tissue augmentation. Surgical methods have disadvantage of surgical morbidity. Commercially available injectable materials have the disadvantages such as resorption, short-term effect. repeated application and hypersensitivity. Significant shortcoming of cell therapy using autologous fibroblasts is delay of treatment effect. Chitosan/${\beta}$-glycerol phosphate (GP) solution has thermosensitive property and allows sol-gel transition at physiologic pH and temperature. These properties may resolve the delay of treatment effect. The purposes of this study are to evaluate the viscosity and pH changes of chitosan/${\beta}$-GP solutions and to evaluate the effect of chitosan/${\beta}$-GP solution on fibroblast proliferation and production of collagen. We measured the viscosity and pH as function of temperature, of the solution containing 1:0.7, 1:0.75, 1:0.8 chitosan (1, 10, 100, 700 kDa) /${\beta}$-GP. Fibroblasts from ears of 5 rats were cultured in chitosan/${\beta}$-GP solutions for 3 weeks. Cell proliferation and collagen contents were measured every week with WST (water-soluble tetrazolium salt) assay and Collagen assay respectively. The Results are 1) Chitosan(100 kDa<)/${\beta}$-GP solution (1:0.75) showed sol-gel transition at physiologic pH and body temperature and injectable properties. It will enable to resolve the delay in treatment effect 2) Cell proliferation and total collagen contents of the control group were increased with time. However, these decreased after the 1st week in experimental group 3) Collagen contents in the experimental group are higher than that of control group. Chitosan/${\beta}$-GP solution may provide favorable conditions for cell function

• 한국화재소방학회논문지
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• 제25권2호
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• pp.33-38
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• 2011

본 연구는 초기 착화지연으로 화재예방에 중요한 역할을 담당하는 방염처리제도에 대한 실태 분석연구로서 현장에서 발생하는 여러 문제점들을 각 시도 소방공무원과 방염업자들과의 회의 및 시공현장 방문을 통해 분석하였다. 분석결과 첫 째, 수요가 작은 시장에서 너무 많은 업체들이 경쟁을 하고 있고 이로 인해 방염에 대한 전문성이 없는 일부 업자들은 원가절감을 위해 부실시공을 하는 등의 문제가 발생하고 있으며 둘 째, 현재 실시되고 있는 현장방염처리 검사제도는 검사자가 현장에서 직접 성능검사를 실시하지 못하고 시공자가 제출한 샘플로 방염성능검사를 실시하기 때문에 시료채취의 문제점과 제출된 시료의 신뢰성 및 현장의 방염성능 확보에 의문을 갖는 등의 문제가 발생하고 있다.