• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4A
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• pp.581-590
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• 2008

The panels are used as a composite part of the completed deck. They replace the main bottom transverse deck reinforcement and also serve as a form surface for the cast-in-place concrete upper layer that contains the top of deck reinforcement. In this paper, three types of the detail for joints was selected and their structural performance in terms of strength and crack contral was investigated through static tests on composite beams. Form the results, the validity of loop joints for continuity of half-depth precast deck was observed and especially an overlapping length of loop joint and transverse reinforcement were checked. The results suggest that increasing the loop overlapping length increases the flexural strength of half-depth precast deck with loop joints. In terms of crack contral, the loop joint with transverse reinforcement showed better performance.

• The International Journal of Costume Culture
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• v.7 no.2
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• pp.77-86
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• 2004

The purpose of this study is to characterize physical and tensile properties according to a knitting method as basic materials for solving the difficulties that occur due to the fact that the crosswise elongation is most different among knit stitch at the time of measuring elongation of knitwear. The sample used for this study was wool $100\%$ and was knitted into two, that is, controlled loop length controlled to properties of structure and fixed loop length by using Shimaseiki SES-124S 12G computer automatic flat knitting machine with DSCS device. Also, the density of rib fabric was 12gauge and its quantity was a total of seven of $0{\times}0,\;1{\times}1,\;2{\times}1,\;2{\times}2,\;3{\times}3,\;4{\times}4$ and including plain fabric, and knitted 2 pieces of sample of 300 wale${\times}400$ course. In conclusion, rib stitch has the much higher stretch rate in the direction of the course than other stitches.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.7 no.2
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• pp.10-15
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• 2011

A ground loop heat exchanger for the ground source heat pump system is the core equipment determining the thermal performance and initial cost of the system The length and performance of the heat exchanger is dependent on the ground thermal conductivity, the operation hours, the ground loop diameter, the grout, the ground loop arrangement, the pipe placement and the design temperature. The result of this simulation shows that higher thermal conductivity of grouting materials leads to the decrease length of geothermal heat exchanger from 100.0 to 84.4%.

• Journal of Korean Port Research
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• v.11 no.2
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• pp.145-156
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• 1997

The purpose in this study is development of model for the Container Terminals of Pusan Port, First of all, Quantitive and Qualititve factors are characterized which effects on Physical Distribution System in Container Terminals. The System Dynamics method is used to develope the model by using these factor. This model is able to present the timinig of investment in Container Terminals of Pusan Port. Six models are showed by change of parameters in System Dynamics, in this paper. In the model, Five feedback loop were found. Loop 1 : Number of Liners$\rightarrow$Number of Congested ships$\rightarrow$Port's Charges$\rightarrow$Export & Import Cargo Volumes$\rightarrow$Number of Liners$\rightarrow$The will to investment of government$\rightarrow$Length of berth→Number of Liners. Negative loop was acquired. Loop 2 : Port's Charge$\rightarrow$Economic of Port$\rightarrow$The will to Private management$\rightarrow$Efficiency for Port's Operation$\rightarrow$Port's Charges. Positive loop was acquired. Loop 3 : Number of Congested ships$\rightarrow$Planning for future development$\rightarrow$Information Service$\rightarrow$Support service for port's user$\rightarrow$Number of Congested ships. Negative loop was acquired. Loop 4 : Number of Congested ships$\rightarrow$Planning for future development$\rightarrow$Extent of stacking area$\rightarrow$Number of handling equipmint$\rightarrow$Number of Congested ships. Negative loop was acquired. Loop 5 : Export & Import Cargo Volumes$\rightarrow$Number of Liners$\rightarrow$Econmic of Port$\rightarrow$Support service for port's user$\rightarrow$Export & Import Cargo Volumes. Positive loop was acquired. System's level variables were selected as followings ; Number of Liners, Number of Congested ships, Export & Import Carge Volumes, Length of berth, and Port's Charges. As result of simmulation of model, fluctuation of respective year was found in level variables. This fluctuation can be used properly to present timing of investment.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.9 no.4
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• pp.9-14
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• 2013

A ground loop heat exchanger for the ground source heat pump system is the important equipment determining the thermal performance and initial cost of the system. The length and performance of the underground heat exchanger is dependent on ground thermal conductivity, operation hours, ground loop diameter, grout, ground loop arrangement, pipe placement and design temperature. In this study we find out heat exchanger length with various design factor.

• Korean Journal of Optics and Photonics
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• v.12 no.6
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• pp.507-510
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• 2001

A numerical analysis based on the nonlinear Schroedinger equation is presented to analyze the propagation stability of the average soliton in a simple nonlinear amplifying loop mirror. The ratio of amplification period to soliton period and the length fraction of the erbium-doped fiber in the loop are varied to investigate their effects on the soliton stability. It is observed that stable soliton propagation is obtained even when the amplification period is only slightly shorter than the soliton period when the length fraction of the erbium-doped fiber in the loop is small, which is different from the previously published condition for stable average soliton propagation.

• Nuclear Engineering and Technology
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• v.53 no.11
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• pp.3597-3611
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• 2021

The present paper studies the thermal-hydraulic behaviour of the rectangular supercritical natural circulation loop (SCNCL) using numerical model of one dimensional. Then the results of this model is confirmed with experimental and benchmark results. Variations with several geometric parameters like loop diameter, riser length, and heater length and operating conditions like heater inlet enthalpy, pressure, friction factor, and inlet and exit loss coefficient on steady-state performance are investigated for various orientations like HHHC, HHVC, VHVC and VHHC of the heater and cooler. The chances of existing static instability (Ledinegg excursion) has been investigated, which reveals that it can arise only in a low inlet enthalpy condition, far from the suggested various orientations of heater and cooler.

• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.4
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• pp.10-15
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• 1983

In this paper effective methods of demodulation and equalization in a 9600 bps modem have been studied. To reduce the number of multiplications required per symbol in demodula-tion, the method of using a decimation filter is presented. In the equalizer the optimum step size and the steady state mean-squared error (MSE) are obtained from computer simulation results. The performance of the first-order carrier phase tracking loop is compared with that of the second-order loop when carrier frequency offset exists. In addition, the finite word length effects in the equalizer are studied.

• Journal of the Korean Society of Industry Convergence
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• v.3 no.4
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• pp.337-343
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• 2000

Physical properties of matt georgette knitted fabrics, which has been developed recently, were investigated to provide fundamental information for the textile industry. Dimensional characteristics were examined with three different loop lengths, where the plain knitted fabrics were knitted with cotton yam and polyester yarn. The matt georgette plain knitted stitch was fully relaxed after wet relaxation treatment at $130^{\circ}C$ for 30minutes and subsequent tumble dry treatment at $70^{\circ}C$ for 90minutes. As the treatment temperature of wet relaxation became higher and the loop length did shorter, all of stitch density, course density and wale density were increased with 31 of $K_1$ 8.3 of $K_2$ and 3.8 of $K_3$. Also, The higher value of $K_4$ could be obtain with shorter loop length. When the loop length became longer, the $K_4$ value was varied in a wide range with the treatment of wet relaxation and subsequent tumble dry.

• Journal of Korea Multimedia Society
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• v.14 no.3
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• pp.414-422
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• 2011

The paper is for top and bottom symmetrical phase controlled loop antenna using for multi-media devices. We developed a top and bottom phase control loop pattern arrangement methods for loop antenna in mobile devices like as a cell phone and PCS, WCDMA. In the loop antenna pattern, arrange close adhesive the loop antenna pattern $180^{\circ}$ cycle in wave length, the radiated electro-magnetic wave from close adhesive loop pattern in $180^{\circ}$ become to coherent wave than the phase controlled loop antenna has high efficiency and high radiation gain. To acquire a wide band width on phase controlled loop antenna, we arrange a top and bottom symmetrical architecture loop pattern that bas a $180^{\circ}$ wave length in each layer. Top and bottom each layer bas a U form pattern separated $90^{\circ}$ wave length each other. This architecture cause a well balanced electro-magnetic flow control that acquired wide bandwidth resonance response in loop pattern antenna. In experiment, we designed a WCDMA mobile multi-media antenna in $40mm{\times}6mm$ area thickness 0.2mm, in that passive experiment the radiation efficiency is over 50% and over 0dBi radiation average gain was acquired, in the active experiment in real multi-media device we acquired -4dBi average gain and 43% transmit/receive efficiency.