• Journal of the Korean Society for Railway
• /
• v.2 no.3
• /
• pp.36-45
• /
• 1999

The basic idea of cable-stayed girder bridges is the utilization of high strength cables to provide intermediate supports for the bridge girder so that the girder can span a much longer distance. In the cable-stayed bridge, the cables exhibit nonlinear behavior because of the change in sag, due to the dead weight of the cable, which occurs with changing tension in the cable resulting from the movement of the end points of the cable as the bridge is loaded. Techniques required for the static analysis of cable-stayed bridges has been developed by many researchers. However, little work has been done on the dynamic analysis of such structures. To investigate the characteristics of the dynamic response of long-span cable-stayed bridges due to various dynamic loadings likes moving traffic loads. two different 3-D cable-stayed bridge models are considered in this study. Two models are exactly the same in structural configurations but different in finite element discretization. Modal analysis is conducted using the deformed dead-load tangent stiffness matrix. A new concept was presented by using divided a cable into several elements in order to study the effect of the cable vibration (both in-plane and swinging) on the overall bridge dynamics. The result of this study demonstrates the importance of cable vibration on the overall bridge dynamics.

• Fibers and Polymers
• /
• v.6 no.1
• /
• pp.55-65
• /
• 2005

Extensible elastica solutions of two-dimensional deflection of crimped fiber cantilever of circular wavy crimp were obtained for one end clamped boundary under concentrated, inclined and dead tip load Fiber was also regarded as a linear elastic material. Crimp was described as a combination of semicircular arcs smoothly connected with each other having con­stant curvature of all the same magnitude and alternative sign. Also the inclined load direction was taken into account. The solutions were expressed as the recursive forms of integrals in two different cases, which can also be transformed to elliptic integrals respectively. Comparing the data with inextensible ones was carried out. Consequently in the solution, the normal strain of neutral axis is expressed in terms of cross-sectional area, second moment of area and normalized load parameter. Examples of the circular cross-sectioned fiber are presented. As a result, the differences of normalized load between inexten­sible and extensible elastica solutions when the radius ratio becomes 0.1 were maximum $\Lambda$ = 0.1.

• Membrane Journal
• /
• v.8 no.3
• /
• pp.170-176
• /
• 1998

A study on the bioconversion of soluble starch to cyclodextrin(CD) homologue by CGTase was performed in the membrane-enzyme reactor equipped with a dead-end type membrane module. in the batch reactor, the total conversion of soluble starch to CD homologue was decreased rapidly from a maximum value of 45 % with increasing reaction time due to the product inhibition and breakdown of CD homologue to the reducing sugars. However, in the membrane-enzyme reactor, the total conversion of soluble starch was maintained at a constant value of 35 % throughout the reaction, since the membrane(MWCO = 10,000) promptly separated CD homologue from the reaction mixture. After the macdon for 24 hr in the membrane-enzyme reactor using a 10 % soluble starch solution, the cumulative production amount of CD homologue was about 3.7 kg/m$^2$ at the operating pressure of 2 atm.

• Journal of Navigation and Port Research
• /
• v.27 no.4
• /
• pp.383-388
• /
• 2003

.Ports are usually designed as a dead en port. With an increasing tendency of ship size, the problems such as maneuvering difficulty, turning basin, tugboat fee, etc. are getting to be pointed out. For solving such problem, the conversion of the idea fro dead end port to one-way through port is encourage. To examine the advantage of one-way through port, a quantitative and systematic analyzing procedure is needed. For this, this paper evaluated the preference on the three way of departture using the fuzzy measure and integral model.

• Journal of the Korea Society of Computer and Information
• /
• v.19 no.1
• /
• pp.119-130
• /
• 2014

This paper proposes GAPS, a practical genetic algorithm based pathfinding system for conveniently analyzing various networks. To this end, the GAPS is developed through integration of the intuitive graphic user interface for network modeling, the database management system for managing the data generated in modeling and exploring procedures, and a simple genetic algorithm for analyzing a wide range of networks. Especially, previous genetic algorithms are not appropriate for analyzing the networks with many dead-ends where there are few feasible paths between the given two nodes, however, GAPS is based on the genetic algorithm with the fitness function appropriate for evaluating both feasible and infeasible paths, which enables GAPS to analyze a wide range of networks while maintaining the diversity of the population. The experiment results reveal that GAPS can be used to analyze both networks with many dead-ends and networks with few dead-ends conveniently, and GAPS has several advantages over the previous genetic algorithms for pathfinding problems.

• Journal of Chest Surgery
• /
• v.20 no.1
• /
• pp.71-80
• /
• 1987

Twenty six patients were operated a total correction of tetralogy of Fallot between Jan., 1984 and July, 1985 at the Dept. of thoracic and cardiovascular surgery, Chonnam University Medical School, and a comparison between the survived group [n = 18] and the dead group [n = B was performed to detect factors influencing laboratory data, cineangiographic findings, operative findings and methods, and pump time. Following results were obtained, 1. There was no significant difference between two groups in the preoperative P.O2 and hematocrit level. 2. The size of the interventricular defect was not related to the operative mortality. 3. There was a significant difference in mortality rate between combined type of stenosis of pulmonary artery, valve and infundibulum and other types of right ventricular outflow tract stenosis. 4. There was a significant difference in mortality rate between the transannular patch reconstruction and other types of operative procedure. 5. There was no significant difference between two groups in total bypass time and aortic time. 6. There was no significant difference between two groups in left ventricular end diastolic volume and right ventricular end diastolic volume. 7. The operative mortality was related to the ratio of the diameter of the pulmonary valve annulus or each pulmonary artery to the ascending or descending aorta in cineangiographic findings, but there was no statistical significance of which probably is due to the lack of the total number of patients.

• Journal of Chest Surgery
• /
• v.33 no.7
• /
• pp.585-589
• /
• 2000

Lung transplantation has been successfully employed for variety of obstructive lung disease. Single lung transplantation has become a therapeutic option for end-stage obstructive lung disease. The patient, a 57 year old man with emphysema, suffered from severe dyspnea, which progressively aggravated him for the last three years. A single lung transplantation was performed from a young brain-dead donor on April 7th, 1999 in the department of thoracic surgery, Respiratory Center, Yongdong Severance hospital, yonsei University. The immunosuppressive regimen was based on cyclosporine A and azathioprine from beginning, adding steroid. Single lung transplantation was feasible and beneficial in patients with end-stage emphysema.

• Membrane and Water Treatment
• /
• v.1 no.1
• /
• pp.61-74
• /
• 2010

This paper will integrate models at different levels (from filtration, backwashing to chemical cleaning and membrane lifetime) that can be used to minimize overall operating costs of a dead-end ultra filtration process that is used for the purification of surface water. Integration of the models leads to a multi-level optimization problem (at different levels different objectives should be reached). This problem is solved as a MINLP. Systematic modelling and optimization of membrane systems is not extensively discussed in the scientific literature. In this paper the first steps are taken in the formulation of proper models and the use of systems engineering tools to come to real optimal operating conditions. The optimized variables are used to calculate fouling profiles which can subsequently be used as inputs for a control system that actually enforces the profiles to a real pilot plant.

• Journal of Energy Engineering
• /
• v.23 no.3
• /
• pp.1-6
• /
• 2014

The more or less homogeneous fuel-air mixture that exists at the end of the compression process is ignited by an electric ignition spark from a spark plug shortly before top dead center. The actual moment of ignition is an optimization parameter; it is adapted to the engine operation so that an optimum combustion process is obtained. Brake mean effective pressure (BMEP) of the spark ignition energy control device (IECD) than conventional spark system at the stoichiometric mixture is increased about 9%. For lean burn engine, the lean limit is extended about 25% by using the IECD. It was considered the stability of combustion by the increase of flame kernel according to the high ignition energy supplies in initial period and discharge energy period lengthen by using the IECD.

• Proceedings of the KSME Conference
• /
• 2004.11a
• /
• pp.545-550
• /
• 2004

KSTAR cryostat is a 8.8 m diameter vacuum vessel that provides the necessary thermal barrier between the ambient temperature test cell and the supercritical helium cooled superconducting magnet providing the base pressure of 1 ${\times}$ $10^{-3}Pa$. The cryostat is a single walled vessel consisting of central cylindrical section and two end closures, a flat base structure with external reinforcements and a dome-shaped lid structure. The base structure has 8 equally spaced support legs anchored on the concrete base. The cryostat vessel design was executed to satisfy the performance and operation requirements. The major loads considered in the structural analysis were vacuum pressure, dead weight, electromagnetic load driven by plasma disruption, and seismic load. Based on the fabrication and inspection procedures for the vessel, cryostat vessel was fabricated and inspected. It was confirmed that the inspection results were acceptable.