• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.349-355
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• 1992

In order to explore feeding practices of large ruminants and methods followed in the rural areas, an exploratory survey was made during the period from January 1988 to January 1989 in eight different agro-ecological areas of Bangladesh in relation to the existing seasons and farmers' categories. The study shows what feeding practices varied (p<0.01) from area to area and season to season but not with the farmers' category. Considering the overall picture of feeding practices existing in the country, it can be observed that bigger proportion of farmers practiced stall feeding and tethering ($38.4{\pm}35.1$) followed by stall fed ($34.3{\pm}35.2$) and grazing or tethering ($17.3{\pm}26.7$). The figure with wider deviations indicates that farmers in the rural areas did not follow a smooth feeding practice, the system is rather a complex, heterogenous and a mere consequence of existing land use system. The results of feeding methods of by-product concentrates indicate that it also varied (p<0.01) from area to area but however, not with seasons and farmers' category. It is observed that bigger proportion of farmers fed concentrates to their animals mixed with water ($74.1{\pm}30.3$) followed by mixed with roughage and water ($10.3{\pm}13.3$) or fed alone ($5.6{\pm}14.2$). The method like feeding practice is also complex and heterogenous in the rural areas of Bangladesh. Hence, it is needed to develop a strategic feeding system and method identifying the problems associated with those.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.10 s.175
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• pp.174-185
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• 2005

This paper presents the design, fabrication, and testing results of a dual stage actuator system for a fine positioning of magnetic heads in magnetic disk drives. A novel rotary microactuator which is electrostatically driven and utilized as a secondary actuator was designed. The stator and rotor electrodes in the microactuator was revised to have the optimal shapes and hence produces much higher rotational torque compared with the conventional comb-shape electrodes. The microactuators were successfully fabricated using SoG(silicon on glass) processing technology, which is known as being cost-effective. The fabricated microactuator has the structural thickness of $45{\mu}m$ with the gap width of approximately $3{\mu}m$. The dynamic characteristic of microactuator/slider assembly was investigated, and its natural frequency and DC gain were measured to be 3.4kHz and 32nm/V, respectively. The microactuator/slider assembly was integrated into a HDD model V10 of Samsung Electronics Co. and a dual servo algorithm was tested to explore the tracking performance of dual stage actuator system where the LDV signals instead of magnetic head signals were used. Experimental results indicate that this system achieves the tracking accuracy of 30nm. This value corresponds to a track density of 85,000 track per inch(TPI), which is about 3 times greater than that of current hard disk drives.

• Journal of Information Management
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• v.37 no.2
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• pp.109-136
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• 2006

The development of Semantic Web basically requires knowledge which is induced by the formalization and semantization of information, and thus ontology should be introduced as a knowledgization tool. URI(Uniform Resource Identifier) is an indispensible scheme to uniquely indicate individuals on ontology. However, it is difficult to find the use cases of identifiers or URIs in real data sets including science & technology publications. This paper describes the method to construct, manage, and serve reference information based on URI which is a crucial component on establishing national R&D reference information ontology. We expect the reference information which was acquired from about 7,000 proceeding papers would be adopted to Semantic Web applications such as researcher network analysis and outcome statistics.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.4 s.316
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• pp.1-9
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• 2007

An embedded system is implemented in this work by removing PCMCIA dedicate controller chip from ARM processor based embedded Linux system. In this paper, we propose PCMCIA interface architecture by using Ad hoc methods for wireless network. The proposed system is developed based on S3C2410A processor and it is interfaced with PCMCIA socket by using combinational digital logic circuits. It is interesting to observe that Ad hoc interface provides $97.9%{\sim}102.49%$ performance when compared with dedicate controller systems. The results indicate that the proposed method simplifies the system without loss of performance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.113-113
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• 2008

Cu CMP (Chemical Mechanical Planarization) has been used to remove copper film and obtain a planar surface which is essential for the semiconductor devices. Generally, it is known that chemical reaction is a dominant factor in Cu CMP comparing to Silicon dioxide CMP. Therefore, Cu CMP slurry has been regarded as an important factor in the entire process. This investigation focused on understanding the effect of corrosion inhibitor on copper surface and CMP results. Benzotriazole (BTA) was used as a corrosion inhibitor in this experiment. For the surface analysis, electrochemical characteristics of Cu was measured by a potentiostat and surface modification was investigated by X-ray photoelectron spectroscopy (XPS). As a result, corrosion potential (Ecorr) increased and nitrogen concentration ratio on the copper surface also increased with BTA concentration. These results indicate that BTA prevents Cu surface from corrosion and forms Cu-BTA layer on Cu surface. CMP results are also well matched with these results. Material removal rate (MRR) decreased with BTA concentration and static etch rate also showed same trend. Consequently, adjustment of BTA concentration can give us control of step height variation and furthermore, this can be applicable for Cu pattern CMP.

• Journal of Aquaculture
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• v.13 no.2
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• pp.137-145
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• 2000

Capacity of water treatment of the three phase fluidized bed reactor as a biofilter in the seawater recirculating system was evaluated. The water treatment system consists of fluidized bed reactor for ammonia removal, cartridge filter for solid removal and ozone contactor for disinfection. Mean concentration of water quality parameters: COD, TAN, $NO_2$-N, $NO_3$-N, SS and alkalinity were 9.0, 0.22, 0.05, 20.0, 9.5 and 70.0 mg/l, respectively; the relevant values were 7.6 for pH and 3.64 NTU for turbidity. These indicate the maintenance of good water quality by the treatment system. The influent TAN loading rate in to the fluidized bed reactor ranged from 4.3 to 32.9 g/$m^3$/day, and averaged to 20 g/$m^3$/day. TAN removal efficiency of each phase of the fluidized bed reactor was 47-60%, indicating the effective ammonia removal. During operation the effluent of fluidized bed reactors also maintained the unionized ammonia nitrogen level below 0.002 mg/l.

• Journal of the Korean Solar Energy Society
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• v.22 no.3
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• pp.47-56
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• 2002

The office is an excellent candidate for implementing daylighting techniques because of the relatively high electric lighting power densities and long daytime use pattern. The quantity of light available for a space can be translated in term of the amount of energy savings through a process of a building energy simulation. To get significant energy savings in general illumination, the electric lighting system must be incorporated with a daylight - activated dimmer control. A prototype configuration of an office interior has been established and the integration between the building envelope and lighting and HVAC systems is evaluated based on computer modeling of a lighting control facility. First of all, an energy-efficient luminaire system is designed for both a totally open-plan office interior and a partitioned office. A lighting design and analysis program, Lumen-Micro 2000 predicts the optimal layout of a conventional fluorescent lighting fixture to meet the designed lighting level and calculates unit power density, which translates the demanded amount of electric lighting energy. A dimming control system integrated with the contribution of daylighting has been applied to the operating of the artificial lighting. Annual cooling load due to lighting and the projecting saving amount of cooling load due to daylighting under overcast diffuse sky are evaluated by a computer software, ENER-Win. In brief, the results from building energy simulation with measured daylight illumination levels and the performance of lighting control system indicate that daylighting can save over 70 percent of the required energy for general illumination in the perimeter zones through the year. A 25 % of electric energy for cooling may be saved by dimming and turning off the luminaires in the perimeter zones.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.169-175
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• 2006

Potentiometric biosensor using flow injection analysis system was developed to determine citrate concentration in foods. Biosensor system consisted of sample injector, peristaltic pump, enzyme reactor, carbonate ion selective solid-state electrode, reference electrode, detector, and recorder. Enzyme reactor was prepared with immobilized citrate lyase and oxaloacetate decarboxylase. Carbonate ions produced through enzyme reactions of citrate were potentiometrically detected by ion selective electrode. Optimum conditions for biosensor system were investigated. Interference effect of major sugars and organic acids was less than 5% on citrate biosensor system. Citrate concentrations in fruit juices were determined by biosensor and gas chromatography. No significant difference was observed between two analytical methods. Results indicate citrate biosensor is useful in determining citrate concentration in foods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.2068-2077
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• 2009

While six sigma project management systems have been widely used as a knowledge management systems, no one has proposed an empirical explanation for impacts of project management systems on project performance. This study proposes a structural equation model of the project management system that relates learning/growth, internal growth, customer performance, and financial effects based on six sigma project performance. The relationships are investigated using data collected from a sample of green and black belts. The results indicate that there are a causal relationship with use of project management and learning/growth and internal process, internal process and customer performance, and customer and financial performance. However, there is no relationship between internal process and financial effects. The results suggest that six sigma project system could effectively be implemented as a knowledge management system to improve six sigma performance of green an black belts. This study also compares index of SEM's model fit of research model and that of alternative models for further analysis. The result shows that index of research model of index is better than that of alternative model.

• Journal of the Korean Institute of Gas
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• v.13 no.6
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• pp.9-14
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• 2009

In this study, the stress and deformation characteristics of corner protection in which is fabricated in an insulation area have been analyzed using a finite element method. The proposed corner protection may increase the strength and leakage safeties of conventional LNG storage system. The stress and deformation of LNG storage tank system are computed for an insulation panel box, membrane inner tank, and prestressed concrete outer tank. The FEM computed results indicate that the stress and displacement of new membrane LNG tank system with a corner protection between an inner tank and an outer tank are reduced in comparison to those of a conventional membrane LNG tank. This is explained that the strength safety of LNG membrane tank system may be increased due to a strength stiffness of a corner protection.