• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.343-346
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• 2000

In most inverter/converter applications SVPWM method is the preferred approach for it shows good characteristics in linear modulation range and waveform quality. in this paper we propose a new carrier based SVPWM method for multi-level system. First we survey the conventional carrier based SVPWM method and investigate the problem of the conventional one for the multi-level system with the focus on the switching frequency harmonic flux trajectories. Finally we propose a new carrier based SVPWM method that can reduce harmonic distortion. Simulation and experimental results are given for the verification of the proposed SVPWM method.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1998.10a
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• pp.133-136
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• 1998

Supporting decision-makers involves not only functions of conventional DSS such as problem identification, alternative generation and selection but also education and business processing. The purpose of this paper is to propose Decision-Maker Support System (DMSS) that comprehensively supports decision-makers who should enhance their decision quality. The DMSS consists of three core subsystem: distance learning system, conventional DSS and ERP system.

• Journal of the Korea Society for Simulation
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• v.3 no.1
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• pp.1-16
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• 1994

In this paper, the modeling capabilities of an object-oriented simulator, AgvTalk is demonstrated by designing and simulating a conceptually configuration of AGV systems, known as the tandem configuration. The characteristics and design methodology in AgvTalk are described between the tandem configuration for AGV systems and conventional AGV systems. Also, simulation between the conventional AGV system and its corresponding tandem AGV system are compared with AgvTalk in the job shop environment. From the simulation results, the characteristics of each system observed are discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.10
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• pp.1469-1474
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• 2003

Twenty four weaner lambs, eight each of Marwari, Patanwadi and Merino${\times}$Patanwadi breeds (9.9 to 10.8 kg) were randomly divided into two dietary treatments on body weight basis Viz. $T_1$-conventional (Maize-38%, GN Cake-25%, Rice Polish-24%, Jaggery solution-10%, Mineral mixture-3%) and $T_2$-supplemented non conventional group (GN Cake-25%, Rice Polish-14%, Mango seed kernel-25%, Babul Pods chuni-23%, Jaggery solution-10%, Mineral mixture-3%). The Jaggery solution was prepared by mixing 6.5 kg Jaggery and 3.5 kg water. The average final body weight at the end of the experiment was recorded to be $19.33{\pm}0.76$ and $19.72{\pm}0.8kg$ in conventional and non-conventional groups, respectively. The total dry matter intake (DMI) during the entire experiment period was recorded to be $89.56{\pm}5.19$ and $95.08{\pm}1.06$ (kg/head) and $532.83{\pm}9.94$ and $566.75{\pm}10.49g/d$ in conventional and nonconventional groups, respectively. The body weight gain and body measurements did not influenced by diet. The ration effect was found to be significant when the DMI was expressed in terms of g/d. The crude protein (CP) and digestible crude protein (DCP) intake/head and per kg gain observed during experiment under conventional and non-conventional treatment group did not differ from each other. However, the total digestible nutrients (TDN) intake per kg gain was significantly (p<0.05) higher in supplemented non-conventional group. The intake values of DCP and TDN were more or less in agreement with Indian Council Agricultural Research (1985) recommendations. The estimated total feed cost (Rs./animal) for experimental lambs was $274.16{\pm}8.57$ and $242.67{\pm}5.10$ in conventional and non- group, respectively. The non-conventional group had significantly (p<0.05) lower feed cost (11.6%). The return as percent of feed cost and feed cost/kg dressed weight were $92.89{\pm}5.58$ (%) and Rs. $35.40{\pm}1.11$ and $122.61{\pm}5.06$ (%) and Rs.$30.47{\pm}1.71$ in conventional and non-conventional group (p<0.05), respectively which is the reflection of significantly lower total feed cost incurred during feeding in non-conventional group. Lambs fed non-conventional based diet had similar live weights as those fed conventional diets but costed less money to achieve those weights.

• Journal of the Korea Society of Computer and Information
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• v.14 no.7
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• pp.123-132
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• 2009

The perforrnance and portability of mobile applications can be greatly increased by adopting proxy modiles which exists between the conventional system and the device. When mobile devices collaborate with the conventional computers, there are problems to address: a battery life problem, limited input and output methods, and intermittent wireless connection. Those issues are magnified in the multimedia collaboration environment since it works in a real-time condition and the size of the message in the system is big in many cases. Additionally, because multimedia collaboration system softwares are too heavy and complex for mobile devices, it is veη hard to integrate them with conventional systems. In this paper, we describe our design and its implementation of a novel approach to map events (i.e. messages) using a proxy for mobile applications. We adopt a proxy to provide a content adaptation (i.e. transcoding) where the message contents are customized. Also, we design a mobile version publish/subscribe system to provide communication service for mobile device in loosely coupled and flexible manner. We present our empirical results which show that our design can be efficiently implemented and integrated with a conventional multimedia collaboration system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.4 no.1
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• pp.38-42
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• 1979

This paper reports that a DDD system controlled by Stored Program Control(SPC) method was constructed and performance testresults were presented using a microprocessor instead of using conventional Wired Program Control(WPC) method. It is shown that the system was designed using a STD O/G unit which has only Point to Point(PTP) access function due to selector driving method as a O/G repeater of this system without any modification. When the system is adopted to a toll exchange system for medium and / or small city, it is expected that the system can be made with small size, high reliability and no use of conventional selector switches. It is also predicted that variation of communication route can be easily realized by simple program modification.

• Korean Journal of Poultry Science
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• v.26 no.3
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• pp.189-193
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• 1999

This experiment was conducted to investigate the effect of floor heating system on housing environment and performance in broiler production. PVC heating pipes(in 25cm spacing) were covered with concrete under the litter. Floor heating system was compared with conventional direct heating system. Each treatment had two replicates of 110 birds each. Litter moisture content was significantly reduced in floor heating system than conventional direct heating system(P〈0.05). Dust concentration was higher in floor heating system because of low litter moisture content. CO$_2$concentration was 2,900ppm and 1,500ppm on the direct heating system and floor heating system, respectively at the age of 1 week. Body weight was significantly higher in floor heating system at 7 weeks of age(P〈0.05). The results of the trial show that floor heating was useful heating system for broiler production.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.3
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• pp.281-288
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• 2008

Cake resistance is influenced by floc size deposited on membrane surface. Enlarging floc size can reduce cake resistance. The small particles are enlarged by coagulation and flocculation process in conventional mixing tank at membrane filtration system. Fully-grown flocs for reducing the cake resistance, however, are ruptured while passing through a pump. In light of this fact, this study aims to experimentally look at the reaggregation phenomenon of mixing system. In addition, reaggregation phenomenon of mixing system is compared with first-aggregation of in-line injection system in which coagulant is injected just before a pump. These results suggest that first-aggregation of in-line injection system is better than reaggregation of mixing system for G-value above $3100sec^{-1}$. Since G-value in pipe of actual membrane filtration system are usually larger than $3100sec^{-1}$. The performance of in-line injection system is expected to be better than the conventional mixing tank system.

• Progress in Superconductivity and Cryogenics
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• v.7 no.1
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• pp.37-41
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• 2005

This paper describes the construction scheme of new distribution system using HTS(High Temperature Superconducting) power equipments such as cable, transformer and FCL(fault current limiter). At present, one of the most serious problems in distribution power system, especially for metropolitan complex city, is to obtain the ROW for cable line routes, space for downtown substations and satisfy the environmental protection caused by NIMBY phenomena. Unfortunately, it is expected that this situation will get more and more worse. As the HTS technology to apply in power system Is developed, HTS cable utilizing mass-capacity characteristic can be a useful countermeasure to overcome this problem. This paper describes the application methodology of 22.9kV HTS cable with low-voltage, mass-capacity characteristics replacing the 154kV conventional cable. By applying 22.9kV HTS cable, the HTS transformer with higher capacity for the reduction of space and transformer numbers of downtown substation is necessary. Also, if the leakage Impedance of HTS transformer is same as or lower than that of conventional transformer, the fault current of 22.9kV bus will increase because the HTS transformer capacity is larger than that of the conventional transformer. This means the parallel application of HTS-FCL to reduce the fault current in addition to the HTS cable and transformer can be necessary. With the basic construction scheme of new distribution system, this paper describes the future study points to realize this new distribution system using HTS equipments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.8
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• pp.3054-3067
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• 2015

The phenomena of higher channel cross polarization discrimination (XPD) is mainly observed for future wireless technologies such as small cell network and massive multiple-input multiple-output (MIMO) system. Therefore, utilization of high XPD is very important and space-polarization division multiple access (SPDMA) with dual-polarized MIMO system could be a suitable solution to high-speed transmission in high XPD environment as well as reduction of array size at base station (BS). By SPDMA with dual-polarized MIMO system, two parallel data signals can be transmitted by both vertically and horizontally polarized antennas to serve different mobile stations (MSs) simultaneously compare to conventional space division multiple access (SDMA) with single-polarized MIMO system. This paper analyzes the performance of SPDMA for maximum ratio transmission (MRT) in time division duplexing (TDD) system by proposed dual-polarized MIMO spatial channel model (SCM) compare to conventional SDMA. Simulation results indicate that how SPDMA utilizes the high XPD as the number of MS increases and SPDMA performs very close to conventional SDMA for same number of antenna elements but half size of the array at BS.