• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.11
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• pp.1584-1589
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• 2013

A new and significantly small guided and resonant structure is suggested to take over bulky metallic hollow waveguides used in military satellite transceivers. Below Ku-band, the conventional waveguides resulting in quite heavy transceivers will be replaced by the low profile SIW(substrate integrated waveguide) structures that are distinguished from the others in that the suggested ones have much lower cut-off frequencies by the circuital configuration of DNG(dobule negative) constitutive parameters and become even smaller than the other SIWs. The design scheme is validated by the circuit and full-wave simulations from the guided, resonant, and coupled structures. Besides, a bandpass filter as the suggested coupled structure is fabricated with a cheap substrate in a low-budget fabrication process and its frequency response is measured as verification of the purpose of the design.

• Journal of the Korea Society of Computer and Information
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• v.6 no.1
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• pp.45-50
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• 2001

Congestion may take place in the ATM network because of high-speed cell transmission features, and cell delay and loss also can be caused by unexpected traffic variation. Thus. traffic control mechanisms are needed. One of them to decrease congestion is the cell shaping. This paper proposes a hybrid type cell shaper composed of a Leaky Bucket with token pool, EWMA with time window, and a spacing control buffer. The simulator BONeS with the ON/OFF traffic source model evaluates the performance of the proposed cell shaping method. Simulation results show that the cell shaping concerning the respective source traffics is adapted to and then controlled on the mean bit rate.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.7
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• pp.655-663
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• 2010

DUP (direct underside pressurization) is a device that can considerably increase lift, reduce take-off speed and minimize hump drag when a WIG effect vehicle takes off on the water surface. A 3-dimensional numerical investigation of a WIG effect vehicle with DUP is performed to analyze aerodynamic characteristics and the static height stability. The model vehicle, named Aircat, consists of a propeller in the middle of a fuselage, an air chamber under the fuselage, Lippisch-type wings and a large horizontal T-tail. The lift is mainly increased by the stagnation of the accelerated air coming into the air chamber through the channel in the middle of the fuselage. However, the accelerated air increases drag as well as reduces static height stability.

• Journal of the Korean Society of Costume
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• v.32
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• pp.243-259
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• 1997

The object of this research is to inform readers of the chronikal change of Military Uniform in wars how the features and colors of uniforms have been changed along with the innovations of firearms. Military uniforms can be put into two differ-ent categories which are 'Battle wear' and 'Rank wear' A battle wear features of protec-tion and user fiendliness, These features of a battle wear can possibly minimize injuries and help increase the level of battling perform-ance. On the other hand a rank wear help dis-tinguish soldiers from their ranks and posi-tions. A rank wear symbolizs the pride that soldiers take n their unit and by wearing a rank wear soldiers feel more attached to their collegues and unit. Concrete process of military uniforms is as follows. 1. As firearms were innovated corres-pondant innovation of military uniforms were also needed this innovation were in the formstructure design color etc. 2. In the beginning features of military uniforms changed toward protection and then after social status of solders rised features changed forward show-off Finally as firearms became more fortal camouflage became the most significant feature of the military uniforms. 3. During war colors of military uniforms tended to be a means of show -off and camou- flage and while not in war they functioned as symbol which represent froops and the unit is tradition. 4. Other accessaries support the perforance and the symbolical function of uniforms.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.700-707
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• 2005

The human being continued the processing of improvement for well being life according to scientific results The other hand, All the seaman life take the rest and sleep in ship's office and living room. In this case, many crew took the pain of back spain or deposit the his fatigue, This will be decrease the productivity owing to crew's back spain or fatigue etc. In this study researched the problem of ship's bed mattress and the principle of Well being air mattress in technical standard etc. Specially decreased some kinds of bacillus, germ and many kinds of bacteria by using of tourmaline which emitted the far red light and negative ion from surface of the mattress. We developed and applied the ship's Well being air mattress to off shore and various kind of ship by International Labour Organization convention 192.

• Corrosion Science and Technology
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• v.19 no.2
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• pp.51-56
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• 2020

The objective of this study was to improve properties of plasma sprayed HAp layer to titanium substrate by introducing an intermediate layer with two different methods. Before applying Zn doped HAp coating on titanium substrate, an intermediate layer was introduced by titanium plasma spray or titanium anodization. Heat treatments were conducted for some samples after titanium intermediate layer was formed. Zn doped HAp top layer was applied by plasma spraying. Three-point bending test and pull-off adhesion test were performed to determine the adhesion of Zn doped HAp coatings to substrates. Long-term credibility of Zn doped HAp plasma sprayed coatings on titanium was assessed by electrochemical impedance measurements in Hanks' solution. It was found that both titanium plasma sprayed and titanium anodized intermediate layer had excellent credibility. Strong adhesion to the titanium substrate was confirmed after 12 weeks of immersion for coating samples with titanium plasma sprayed intermediate layer. Samples with titanium anodized intermediate layer showed good bending strength. However, they showed relatively poor resistance against pulling off. The thickness of titanium anodized intermediate layer can be controlled much more precisely than that of plasma sprayed one, which is important for practical application.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.4
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• pp.248-253
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• 2007

We studied the maturation and spawning of female Spanish mackerel (Scomberomorus niphonius) based on 445 specimens collected monthly from January to December 2004 in the coastal waters off Busan. The fork length (FL) of S. niphonius ranged from 26.1 to 105.4 cm, the gonadosomatic index (GSI) of the females was highest in May 2004, and the spawning season take place from April to July. A significant difference was detected in the sex ratio between females and males ($X^2$ test, p<0.01). The percentage of sexually mature females exceeded 50% in the 50-60 cm (FL) size group and reached 100% in the over 70 cm (FL) size group. Fecundity (F) varied between 201,156 and 836,426 egg per female. The relationship between F and FL of the fish was expressed as $F=5.8756FL^{3.8465}$. The relationship F and body weight (BW) was expressed as F=581.421 n (BW)-4108.5. The first spawning length was 41.8 cm (FL.)

• Journal of Families and Better Life
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• v.33 no.5
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• pp.25-35
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• 2015

The purpose of this study was to investigate how work-family spillover differed by employment status of married women and to identify factors related to the differences. This study drew a sample of 332 self-employers, 181 unpaid family workers, and 1,053 wage workers from the 2014 Korean Longitudinal Survey of Women and Families. It was found that negative work-family spillover did not differ by employment status of married women. However, positive work-family spillover was found the lowest in family workers. The regression analysis showed that the difference remained after controlling socio-demographic characteristics, average working hours, and the number of days off per week. The factors related to negative spillover were age, the presence of young children, working hours, and the number of days off. Findings from this study suggest that family workers are most disadvantaged in terms of work-family spillover. Yet there is no policy developed for them. Family policy needs to take them into account in planning and implementing services.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.5
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• pp.170-180
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• 2000

The surface-drainage system, which consists of bio-swale and detention-infiltration Basins and carries out the function of temporary detention-infiltration of runoff, is defined as the "natural drainage system". It is an environmentally sound and economically beneficial practice to reduce run-off by retaining it in swales as much as possible and letting run-off infiltrate into the ground. In order to estimate appropriate capacity of swales, it is necessary to know how long will it take for certain depths of water to infiltrate. The ponding times, or infiltration times, of various depths and of various soil textures, could be estimated with the Green-Ampt Infiltration Model. Included soil textures are loamy sand, sandy loam, loam, silty loam, sandy clay loam and clay loam. Ponding depths are from 10cm to 100cm intervals. Newton-Raphson method is used for the solution of the Green-Ampt equation by a computer program. The computer program was written with the FORTRAN Developer 4.0 v.. Selected ponding depth is acceptable when the sum of the ponding time and the breeding time of mosquitoes is less than the tolerance period of innundation of grasses and trees.and trees.

• ETRI Journal
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• v.37 no.4
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• pp.743-751
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• 2015

Cloud gaming services are heavily dependent on the efficiency of real-time video streaming technology owing to the limited bandwidths of wire or wireless networks through which consecutive frame images are delivered to gamers. Video compression algorithms typically take advantage of similarities among video frame images or in a single video frame image. This paper presents a method for computing and extracting both graphics information and an object's boundary from consecutive frame images of a game application. The method will allow video compression algorithms to determine the positions and sizes of similar image blocks, which in turn, will help achieve better video compression ratios. The proposed method can be easily implemented using function call interception, a programmable graphics pipeline, and off-screen rendering. It is implemented using the most widely used Direct3D API and applied to a well-known sample application to verify its feasibility and analyze its performance. The proposed method computes various kinds of graphics information with minimal overhead.