• Korean Journal of Optics and Photonics
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• v.26 no.5
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• pp.269-274
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• 2015

In this paper we design the optical system for an integrated two-channel TO-type optical transmitter to apply the HDMI interface using the code V simulator. The proposed integrated two-channel optical transmitter has two VCSELs attached in parallel on an 8-pin TO-CAN package, on top of which is a lens filter block ($1mm{\times}2mm{\times}4mm$) composed of hemispherical lenses and WDM filters. Considering two-channel transmitters manufactured with wavelength combinations of 1060nm/1270nm and 1330nm/1550nm, we obtain the optimum value of the diameter of the hemispherical lens as 0.6 mm for both combinations, and the distances L between the lens filter block and ball lens as 1.7 mm and 2.0 mm for the 1060nm/1270nm and 1330nm/1550nm wavelength combinations, respectively. At this time, the focal length f0 of the lens filter blocks for wavelengths of 1060, 1270, 1330, and 1550 nm are 0.351, 0.354, 0.355, and 0.359 mm, respectively, and the focal lengths F of light passing through the lens filter block and ball lens are 0.62 mm for 1060nm/1270nm and 0.60-0.66 mm for 1330nm/1550nm wavelength combinations.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.77-83
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• 2014

Prestressed concrete girder bridge has been one of the most widely used bridges in the world because of its excellent construction feasibility, economic efficiency, serviceability, and safety. In certain situations, the prestressing tendon is supposed to be bent by the construction error and the radius of curvature at the continuous joint of PSC girders, and this leads to the loss of prestressing force. However, this kind of prestress loss is not considered in the design and construction processes. This study proves that the prestress loss occurs at the continuous joint due to the local bending of tendon by the construction error or the radius of curvature. Also, a method that can reduce this type of prestress loss is proposed, and proved by the experiment. The result shows that maximum 10% of prestress loss occurs at the continuous joint and the proposed block-out method can reduce the prestress loss ratio by maximum 5%, approximately. This means that the block-out method can enhance the prestressing efficiency of continuous PSC girder bridges.

• Journal of the Korean Institute of Navigation
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• v.10 no.2
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• pp.83-96
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• 1986

In the restricted sea way such as fair way in harbor, narrow channel etc, the safe ship-handling is a very important problem, which is greatly related with turning ability of ships. It is of great importance that ship-handlers can grasp the position of pivoting point varying with time increase at any moment for relevant steering activities. Mean while, in advanced ship-building countries they study and investigated pivoting point related with turning characteristics, hut their main interest lies in ship design, not in safe ship controlling and maneuvering. In this regards it is the purpose of this paper to provide ship-handlers better under standing of pivoting point location together with turning characteristics and then to help them in safe ship-handling by presenting fact that pivoting points vary according to configuration of ships. The author calculated the variation of pivoting point as per time increase for various type of vessels, based on the hydrodynamic derivatives obtained at test of Davidson Laboratory of Stevens Institutes of Technology , New Jersey, U.S.A. The results were classified and investigated according to the magnitude of block coefficient , length-beam ratio, length-draft ratio, rudder area ratio ete, and undermentioned results were obtained. (1) The trajectory of pivoting point due to variation of rudder angle are all the same at any time, though the magenitude of turning circle are changed variously. (2) The moving of pivoting point is affected by the magnitude of block coefficient, length-beam ratio, length-draft ratio, however the effect by rudder area ratio might be disregarded. (3) In controlling and maneuvering of vessels in harbor, ship-handlers might regard that the pivoting point would be placed on 0.2~0.3L forward from center of gravity at initial stage. (4) The pivoting point of VLCC or container feeder vessels which have block coefficient more than 0.8 and length-beam ratio less than 6.5 are located on or over bow in the steady turning. (5) When a vessel intends to avoid some floating obstruction such as buoy forward around her eourse, the ship-handler might consider that the pivoting point would be close by bow in ballast condition and cloase by center of gravity in full-loaded condition.

• Computers and Concrete
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• v.6 no.1
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• pp.41-57
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• 2009

This paper presents the details of a novel external prestressing technique for strengthening of concrete members. In the proposed technique, transfer of external force is in shear mode on the end block thus creating a complex stress distribution and the required transverse prestressing force is lesser compared to conventional techniques. Steel brackets are provided on either side of the end block for transferring external prestressing force and these are connected to the anchor blocks by expansion type anchor bolts. In order to validate the technique, an experimental investigation has been carried out on post-tensioned end blocks. Performance of the end blocks have been studied for design, cracking and ultimate loads. Slip and slope of steel bracket have been recorded at various stages during the experiment. Finite element analysis has been carried out by simulating the test conditions and the responses have been compared. From the analysis, it has been observed that the computed slope and slip of the steel bracket are in good agreement with the corresponding experimental observations. A simplified analytical model has been proposed to compute load-deformation of the loaded steel bracket with respect to the end block. Yield and ultimate loads have been arrived at based on force/moment equilibrium equations at critical sections. Deformation analysis has been carried out based on the assumption that the ratio of axial deformation to vertical deformation of anchor bolt would follow the same ratio at the corresponding forces such as yield and ultimate. It is observed that the computed forces, slip and slopes are in good agreement with the corresponding experimental observations.

• Journal of Fashion Business
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• v.25 no.3
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• pp.144-158
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• 2021

The purpose of this study is to develop a bodice block suitable for women in their 20s with turtle neck syndrome. The problem of turtle neck syndrome body type was derived through the evaluation of bodice blocks. First, the length of the front bodice was longer and the length of the back bodice was shorter. Second, the front neck point, back neck point, and the shoulder line were not in place. Third, the side neck was pushed up. Fourth, the length of armhole was long and it floated. Fifth, the front hem was attached to the body and the back hem was away from the body. A finally developed pattern was designed by developing four test patterns to solve the problem that appeared in a selected bodice pattern, and a t-test was conducted to determine the difference in the appearance evaluation by virtual clothing between the two patterns, bodice block and the development pattern. According to the result, the fit was not good from the side body because the position of the side neck point was not in a place due to the characteristics of the body shape of turtle neck syndrome, but the problems of the anterior neck position, the position of the back neck point, the shoulder line position, and the armhole shape were improved in the developed pattern.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.1
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• pp.29-36
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• 2016

Lifting lugs are frequently used to transport and to turn over blocks of ship and offshore structures in a shipyard. As the shipbuilding technology has been developed, blocks has become bigger and bigger, and block management technology takes a more important role in shipbuilding to enhance the productivity. For the sake of economy as well as safety in design of lug structure, needed is a more rational design procedure based on the ultimate strength derived through the rigorous non-linear structural analysis considering both the material and geometric non-linearity. This study is aimed at deriving the optimum design of T type lug structure which is frequently used in a shipyard. The optimum thickness of lug's main body is to be determined based on the results of non-linear strength analysis. As far as the present results for T type lugs having various capacity are concerned, it can be said that the present optimum design result can guarantee both safety and economy. From the fact that any regular trend cannot be found in weight reduction to the capacity of lugs, it seems to be necessary to review the current design procedure of lug structure. The present design procedure can be extensively used in design of various types of lug structures used in shipyard.

• Korean Journal of Computational Design and Engineering
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• v.20 no.4
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• pp.420-430
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• 2015

Operator Training Simulators (OTSs) provide macroscopic training environment for plant operation. They are equipped with simulation systems for the emulation of remote monitoring and controlling operations. OTSs typically provide 2D block diagram-based graphic user interface (GUI) and connect to process simulation tools. However, process modeling for OTSs is a difficult task. Furthermore, conventional OTSs do not provide real plant field information since they are based on 2D human machine interface (HMI). In order to overcome the limitation of OTSs, we propose a new type of plant training system. This system has the capability required for collaborative training between operators and field workers. In addition, the system provides 3D virtual training environment such that field workers feel like they are in real plant site. For this, we designed system architecture and developed essential functions for the system. For the verification of the proposed system design, we implemented a prototype training system and performed experiments of collaborative training between one operator and two field workers with the prototype system.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.6
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• pp.75-84
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• 2014

This study aims to develop the program for design of a reinforced earth retaining wall. For this purpose, the external stability such as overturning, sliding and bearing capacity and the internal stability such as pull-out failure and tensile rupture of the reinforced earth retaining wall with the reinforcement spacing and the backfill inclination were examined. In addition, the calculated results from the developed program were verified by comparing with the simulated results based on the three-dimensional finite element analysis. It is expected that this program contributes to effective design of the reinforced earth retaining wall.

• Journal of the Korea Society of Computer and Information
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• v.23 no.1
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• pp.33-39
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• 2018

In this paper, We studied the possibility of SoC(System On Chip) design using infrared image processing IP(Intellectual Property). And, we studied NUC(Non Uniformity Correction), BPR(Bad Pixel Recovery), and CEM(Contrast Enhancement) processing, the infrared image processing algorithm implemented by IP. We showed the logic and timing diagram implemented through the hardware block designed based on each algorithm. Each algorithm was coded as RTL(Register Transfer Level) using Verilog HDL(Hardware Description Language), ALTERA QUARTUS synthesis, and programed in FPGA(Field Programmable Gated Array). In addition, we have verified that the image data is processed at each algorithm without any problems by integrating the infrared image processing algorithm. Particularly, using the directly manufactured electronic board, Processor, SRAM, and FLASH are interconnected and tested and the verification result is presented so that the SoC type can be realized later. The infrared image processing IP proposed and verified in this study is expected to be of high value in the future SoC semiconductor fabrication. In addition, we have laid the basis for future application in the camera SoC industry.

• Korean Institute of Interior Design Journal
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• v.19 no.2
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• pp.197-205
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• 2010

This study examines for the processes of making a architectural significant issue of 20 cases form of Beijjng's hotel through analyzing the space composition from early the 1950's to 1992 in China. In the methods of analyzing process, We study the literatures, research reports and architectural drawings including the site survey. We hope to establish the principle in morphological characteristics and space composition of Beijing's high-rise hotels through analyzing the plan of these hotels. Finally, We find out the principles after researching. Firstly, Beijing's hotels in China faced on the being difficulties through the process of national development especially in political and economical conditions of country and peoples. Consequently, size of the Beijing's hotel developed with the fact that is complicated from that is single styles focused on the medium-sized one, modernizing popularity and the high-rise hotel buildings appeared plentifully and the form appeared with tall building putting first. Secondly, there are many immanent and interlocking styles in hotel's architectural block plans, many composition styles in big sized hotels, in opposition immanent styles in small sized ones and there are many trend of concourse style in medium sized hotels. To the layout of hotel's room inside of the linear styles are many in big and medium sized hotels.