• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.12A
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• pp.1177-1184
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• 2008

Non-line-of-sight (NLOS) propagation can severely weaken the accuracy of ranging and localization in wireless location systems. NLOS bias mitigation techniques have recently been proposed to relieve the NLOS effects, but positively rely on the capability to accurately distinguish between LOS and NLOS propagation scenarios. This paper proposes an energy-capture-based NLOS identification method for LDR-UWB systems, based on the analysis of the characteristics of the channel impulse response (CIR). With this proposed energy capture method, the probability of successfully identifying NLOS is much improved than the existing methods, such as the kurtosis method, the strongest path compare method, etc. This NLOS identification method can be employed in adaptive modulation scheme to decrease bit error ratio (BER) level for certain signal-to-noise ratio (SNR). The BER performance with the adaptive modulation can be significantly enhanced by selecting proper modulation method with the knowledge of channel information from the proposed NLOS identification method.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.643-649
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• 2008

The purpose of this study is to establish a standard for unit cooling load in central control type apartment applied district cooling. The model of unit household was selected. And the standard of coefficient of overall heat transmission, location of unit household, indoor air temperature, solar radiation & thermal conduction at window and interior load was selected, and region, expansion or non-expansion of balcony, pyeong type, azimuth, rate of window area was applied as parameter. And then cooling load simulation was performed. Based on the result of simulation, the synthetic district cooling load was presented for selecting heat source of apartment applied district cooling, and unit cooling load was analyzed according to design parameter.

• Journal of Navigation and Port Research
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• v.30 no.4
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• pp.285-290
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• 2006

Shipping companies consider most of the ship turnaround time as a critical factor when selecting a rolling port for reducing costs. So, many researchers have been studying for the optimization of preplanning and high~performance of the Gantry Cranes (GCs) in container terminals for faster loading and unloading. Therefore, in this paper, we propose an RFID (Radio Frequency Identification) based RTLS (Real-Time Location System) for reducing the ship turnaround time in ubiquitous port environment. In addition, pre-planning based on ubiquitous computing environment will support the GC and Yard Tractors (YTs), and reduce ship turnaround time more effectively. Especially, the proposed method enormously enhances the productivity of loading for the twin-lift system It will reduce the whole lead-time in the process of port logistics.

• Journal of the Korean housing association
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• v.15 no.2
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• pp.43-54
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• 2004

The purpose of this study is to identify the elderly housing farcility design preference by comparing two groups, the present residents living in elderly housing facility and the middle aged. The latter has more housing experiences and more design oriented standard of selecting house for quality of living, while the aged are oriented more in economy and investment. It is identified that both group preferred living in elderly housing facility best to any other elderly housing type, including "aging in place." The aged are not yet very concerned about physically homelike design features, but when the middle aged need the elderly housing, it is recommended that more variety and amenity in its type, location, plan and design features. The idealistic facility planning and management system were suggested.

• IE interfaces
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• v.12 no.2
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• pp.266-273
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• 1999

This study is concerned with the selection of the main stadium for the World Cup football game to be held in Korea in 2002. Alternatives are (1) new construction of the main stadium at Sangam; (2) and remodeling Jamsil stadium constructed for Olympic in 1988; remodeling Munhak stadium in Inchon. For comparison purpose, we consider four decision attributes (environmental, economy. political and technical factors) under which several detailed sub-attributes are defined. Various multi-criteria decision-making tools such as AHP and TOPSIS are applied to find the best location. Our study results indicate that the best selection is remodeling Jamsil stadium. This appears due to heavy emphasis on economy factor in our analysis.

• IE interfaces
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• v.8 no.2
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• pp.171-183
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• 1995

A special purpose automated storage and retrieval system is developed in which information media such as compact disc or video tapes can be stored. Hardware system includes rack, stacker crane with robot arm, conveyor, and bar code reader. Software system includes database for address management, user interface for quick scanning of information media by displaying moving image, and algorithms for selecting the closest open location. Such system is widely applicable to CD library or broadcasting station in the forthcoming information age. In this paper we present detailed procedure and tools that are used in designing and implementing such a special AS/R system.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.161-162
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• 2007

This paper is analyzed the internal type UHF sensors that be able to monitor the condition of the distribution facilities and the location selecting of that sensors. It set the PD cell on the inside of 22.9kV load switchgear and then it executed Partial Discharge test. it introduced the result of the test.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.1
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• pp.26-32
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• 2000

Design load calculations which depend on the thermal characteristics of the building structure such as the wall, roof, and fenestration provide the basic data for selecting an HVAC system and its equipment. Most of domestic multi-family houses include a high thermal storage layer like massive concrete structure and a floor heating structure. This study is to compare the results of the design heating load between steady state and unsteady state calculation in order to comprehend the thermal storage effect in multi-family houses. The design heating load under the steady state calculation is estimated from 5.4% to 7.8% larger than that under the unsteady state in the typical floor of a multi-family house model. The design heating load considered the safety factors like a orientation and location factor also is 21.4% to 26.5% larger than that by the unsteady state calculation. So, the safety factors for use of the practicing engineer are analyzed as the main factor of a heating plant oversizing.

• ETRI Journal
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• v.41 no.3
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• pp.326-336
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• 2019

A wireless power transfer technique can solve the power capacity problem in wireless rechargeable sensor networks (WRSNs). The charging strategy is a wide-spread research problem. In this paper, we propose a demand-based charging strategy (DBCS) for WRSNs. We improved the charging programming in four ways: clustering method, selecting to-be-charged nodes, charging path, and charging schedule. First, we proposed a multipoint improved K-means (MIKmeans) clustering algorithm to balance the energy consumption, which can group nodes based on location, residual energy, and historical contribution. Second, the dynamic selection algorithm for charging nodes (DSACN) was proposed to select on-demand charging nodes. Third, we designed simulated annealing based on performance and efficiency (SABPE) to optimize the charging path for a mobile charging vehicle (MCV) and reduce the charging time. Last, we proposed the DBCS to enhance the efficiency of the MCV. Simulations reveal that the strategy can achieve better performance in terms of reducing the charging path, thus increasing communication effectiveness and residual energy utility.

• Journal of the Korean Society of Visualization
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• v.17 no.1
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• pp.26-33
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• 2019

The rapid increase in the usage of energy in the fast-changing industries has led to resource depletion and environmental conflicts. Many types of research are available on heat exchangers that undergo simple energy conversion processes. The impingement rods discussed in this study improves the durability of the heat exchanger and ensure the stability of the operation. However, it is uncertain about selecting the installation location of the impingement rods. The commercially available CFD code, ANSYS CFX, is used for the impingement rods installation.