• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.294-298
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• 2003

In this paper, the modeling and design of high-Q multilayer passives have been investigated, and multilayer diplexer for GSM/DCS applications has been designed and fabricated using the passives. To minimize the system, the configuration of a multilayer inductor has involved a square spiral structure. Modeling of a multilayer inductor was performed by the subsystems of distributed components, and using the modeling the optimal structures of the high-Q multilayer inductor could be designed by analyzing parasitics and couplings which affect their frequency characteristics. Multilayer diplexer for GSM/DCS application has been designed and fabricated using LTCC technology. LPF for GSM band had the passband insertion loss of less than 0.55 dB, the return loss of more than 12 dB, and the isolation level of more than 26 dB by locating attenuation pole at 1800 MHz. HPF for DCS band had the passband insertion loss of less than 0.82 dB, the return loss of more than 11 dB, and the isolation level of more than 38 dB by locating attenuation pole at 930 MHz.

• 대한가정학회지
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• 제46권9호
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• pp.125-135
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• 2008

The purpose of this study was to examine the effects of young children's age and information processing style in understanding spatial coordinates. For sampling the subjects of this study, Korean version K-ABC Intelligence Test(Moon, Soo-Back, 1997)was conducted with 165 children aged 5-6 who were attending I and G kindergarten in D city. From this pool 30 children who possessed sequential processing style and 30 children who possessed simultaneous processing style were sampled. In order to analyze the understanding of spatial coordinates, a test tool was formulated according to methodology of Blades & Spencer(1989) which was modified. Acquired data was subjected to descriptive and comparative statistical analysis. The following conclusions were arrived at: Firstly, there was significant difference between 5-year-olds and 6-year-olds in understanding spatial coordinates. The 6-year-old group got statistically higher grades than the 5-year-old group in locating a point on the coordinate plane and reading the coordinate numbers. Secondly, there was significant difference between children's information processing style in understanding spatial coordinate. Children with high simultaneous-low sequential processing showed higher performance in locating a point on the coordinate plane and reading coordinate numbers than children with high sequential-low simultaneous processing. Thirdly, after verifying statistical significance of interactivity between young children's age and children's processing strength, there was significant interactive effects in both tasks.

• 한국경영과학회지
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• 제37권4호
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• pp.95-109
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• 2012

Being able to quickly locate valuable medical equipment is critical inside hospitals. In order to utilize limited budget and resources efficiently, accurate locating or tracking is required in many fields. In this research, we focus on how to find the location of missing assets by using RFID in real time indoors to track equipment. When equipment needs to be searched, the purpose of a RFID device is to minimize the time, investment cost and effort spent searching for the equipment. Thus, this research presents a mathematical model of using RFID (both handheld reader and stationary reader) for efficient asset location. We derive the expected time of locating RFID-tagged objects in a multi-area environment where hand-held RF readers are used. We then discuss where to deploy stationary RF readers in order to maximize the efficiency of the search process.

• Asian-Australasian Journal of Animal Sciences
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• 제15권6호
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• pp.900-904
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• 2002

The duration of spatial memory in cattle is potentially important for grazing management. The ability of livestock to remember the location of food patches may lead to uneven range use. In this experiment, how long cattle are able to remember food locations was determined. Six steers were used to conduct this study in a pasture with an 8 row by 8 column grid of 64 plastic containers 5 meters apart. Four randomly chosen containers were loaded with feed pellets. All steers were trained to find the loaded locations until a minimum of empty containers were visited. After this initial training, each steer was tested at 5, 10, 20 and 48 days post-training. Total number of visits (TV), number of containers visited (NC), the ratio of loaded containers (LC) to NC were recorded. Once the steers learned the locations of loaded containers NC did not increase with time since last training up to 48 days (p>0.05). Logarithmic transformation of NC (LNC) was 0.70 and 0.80 for the control and 48 day treatments, respectively. Steers were equally efficient in locating containers with feed. The steers also showed that their ability in locating food was much better than expected by chance (Z>1.62). Findings of the present study do not suggest using spatial memory decay as a tool to promote better grazing distribution. Because steers remembered food locations accurately for at least 48 days.

• 한국소음진동공학회논문집
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• 제22권11호
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• pp.1144-1151
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• 2012

A damage in structure alters its dynamic characteristics. The change is characterized by changes in the modal parameter, i.e., modal frequencies, modal damping value and mode shape associated with each modal frequency. Changes also occur in some of the structural parameters; namely, the mass, damping, stiffness matrices of the structure. In this paper, evaluation of changes in stiffness matrix of a structure is presented as a method not only for identifying the presence of the damage but also locating the damage. It is shown that changed stiffness matrix can be accurately estimated a sensitivity coefficient matrix derived from modifying mode shapes, First, with 4 story shear structure models, the effect of presence of damage in a structure on its stiffness matrix is studied. By using these analytical model, the effectiveness of using change of stiffness matrix in detecting and locating damages is demonstrated. To validate the predicted changing stiffness and its location, the obtained results are compared to the reanalysis result which shows good agreement.

• 한국안전학회지
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• 제20권1호
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• pp.55-61
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• 2005

The purpose of this study is to investigate the effect of circumferential location of local wall thinning defect on the collapse behavior of an elbow. Thus, the present study conducts three-dimensional finite element analysis on the 90-degree elbow containing a local wall thinning at intrados, crown and extrados of bend region and evaluates the collapse moment of wall thinned elbow under various thinning shapes and loading conditions. Combined internal pressure and bending moment are considered as an applied load. The internal pressure of $0\~20MPa$ and both closing and opening mode bending are employed. The results of analysis show that the reduction in collapse moment of the elbow by local wall thinning is more significant for a defect locating at crown than for a defect locating at intrados or at extrados. Also, the effect of internal pressure on the collapse moment of wall thinned elbow depends on the circumferential location of thinning defect and applied bending mode.

• 한국통신학회논문지
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• 제35권4A호
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• pp.401-407
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• 2010

최근 모바일 장치가 널리 이용됨에 따라 사용자에게 더 나은 서비스를 제공하기 위해 실시간 위치 측정 시스템이 사용된다. 무선 신호의 통신을 토대로 위치 측정을 수행하는 RTLS에서 많은 장소에서 발견되는 무선 통신이 어려운 무선 신호의 음영지역은 위치 측정 성능을 저하시키기에 극복해야 한다. 음영지역의 문제를 해결하기 위해 보조 태그 기법과 방향성 안테나를 활용해 하나의 리더를 이용한 위치 측정 기법을 제안한다. 본 논문에서는 RTLS에서 음영지역의 문제를 위치 측정 성능을 유지하며 극복하는 방법을 제안하고 구현하여 실험하였다. 구현된 시스템에서 위치 측정 성공률은 38% 향상되었고 위치 측정 정밀도는 CEP 기준으로 1.13미터의 성능을 나타내었다.

• 한국태양에너지학회 논문집
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• 제34권5호
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• pp.11-22
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• 2014

It is usual to determine silver-town location by people's experienced knowledge or intuition considering many different type of thematic variables simultaneously. This paper is primarily intended to locate sunny silver-town according to catchment-wide solar radiation as single key variable. GIS based solar simulation realistically identified catchment-wide solar radiation in the study area using large scale spatial precision. More than 90% over the worst catchment were identified shadow surfaces while the optimal catchment was heavily covered by sunny radiation surfaces. It is confirmed that standard GIS technology can offers the viable method of measuring and comparing the catchment-wide solar radiation. Guidelines for a replicable methodology are presented to provide a strong theoretical basis for the standardization of factors involved in locating the sunny silver-town; delineation of catchment boundary, solar simulation, catchment-wide comparison etc. They could be used as an evidence to determine sunny catchment in comparison with other catchment, based solar simulation. It is anticipated that this research output could be used as a valuable reference to confirm the potential of introducing the new concept of "catchment specific solar radiation" to support more scientific and objective decision-making in the process of locating silver town.

• 지구물리와물리탐사
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• 제7권1호
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• pp.88-92
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• 2004

To improve the recovery rate of unlocated buried human remains in forensic investigations, there is scope to evaluate and develop techniques that are applicable to the Australian environment. I established controlled gravesites (comprising shallow buried kangaroos, pigs, and human cadavers) in South Australia, to allow the methodical testing of remote sensing equipment for the purpose of grave detection in forensic investigations. Eight-month-old pig graves are shown to provide more distinct identifying results using ground-penetrating radar when compared to four-year-old kangaroo graves. Two further aspects of this research are presented: information (obtained from a survey) relating to the police use of geophysical instruments for locating buried human remains, and the use of electrical resistivity for locating human remains buried in a coffin. The survey of Australian police jurisdictions, covering the period 1995-2000, showed that police searches for unlocated bodies have not successfully located human remains using any geophysical instruments (such as ground-penetrating radar, magnetometers, or electrical resistivity). Lower resistivity readings were found coincident with the 150-year-old single historical burial in a heavily excavated field, in a situation where its exact location was previously unknown.

• 치과방사선
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• 제25권2호
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• pp.535-544
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• 1995

The purpose of this study was comparision of conventional tomography with reformatted computed tomography for dental implant in locating the mandibular canal. Five dogs were used and after conventional tomographs and reformatted computed tomographs were taken, four dentist traced all films. Mandibles were sectioned with 2mm slice thickness and the sections were then radiographed(contact radiography). Each radiographic image was traced and linear measurements were made from mandibular canal to alveolar crest, buccal cortex, lingual cortex, and inferior border. Following results were acquired : 1. Reformatted computed tomographs were exacter than conventional tomography by alveolar crest to canal length of -0.6mm difference between real values and radiographs. 2. The average measurements of buccal cortex to mandibular canal width and lingual cortex to mandibular canal width of conventional tomographs were exacter than reformatted computed tomographs, but standard deviations were higher than reformatted computed tomographs. 3. Standard deviations of reformatted computed tomographs were lower than conventional tomographs at all comparing sites 4. At reformatted computed tomography 62.5％ of the measurements performed were within. : filmm of the true value, and at conventional tomography 24.1％ were. 5. Mandibular canal invisibiity was 0.8％ at reformatted computed tomography and 9.2％ at conventional tomography. Reformatted computed tomography has been shown to be more useful radiographic technique for assessment of the mandibular canal than conventional tomography.