• Asian Journal of Innovation and Policy
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• v.9 no.2
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• pp.223-239
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• 2020

It is important for urban planners and policy makers to understand complex, diverse urban demands and social structure, but this is not easy due to lack of data that represents the dynamics of residents at micro-geographical level. This paper explores how to create population data at at a micro-level by allocating population data to building. It attempted to allocate population data stored in a grid layer (100 meters by 100 meters) into a building footprint layer that represents the appearance of physical buildings. For the allocation, this paper describes a systemic approach that classifies grid cells into five prototypical patterns based on the composition of residential building types in a grid cell. This approach enhances allocation accuracy by accommodating heterogeneity of urban space rather than relying on the assumption of uniform spatial homogeneity of populations within an aerial unit. Unlike the methods that disaggregate population data to the parcel, this approach is more applicable to Asian cities where large multifamily residential parcels are common. However, it should be noted that this paper does not demonstrate the validity of the allocated population since there is a lack of the actual data available to be compared with the current estimated population. In the case of water and electricity, the data is already attached to an individual address, and hence, it can be considered to the purpose of the validation for the allocation. By doing so, it will be possible to identify innovative methods that create a population distribution dataset representing the comprehensive and dynamic nature of the population at the micro geographical level.

• Journal of Korean Society of Steel Construction
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• v.20 no.1
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• pp.1-8
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• 2008

This research carried out to optimize crossbeams and stringers of steel box girder bridges, which are parts of floor system and support loading from the bridge deck. In the current design practice, the crossbeam is densely deployed with a spacing of 6 meters, and the stringer is placed between the crossbeams. The crossbeams and stringer are connected to the deck through slab anchors but the allowable stress of the compression flange is determined by the lateral-torsional buckling. To increase economic efficiency of the steel box girder bridges. the increased spacing of the crossbeam was studied. The study shows that the spacing can be increased up to 10 meters. However, higher strength steel plates are necessary. Shear studs rather than slab anchors are also recommended to prevent lateral-torsional buckling strength of the crossbeams and stringer.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.12
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• pp.1844-1851
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• 2017

As the capacity of the wireless power transmission increases, a higher supply current which may induce current in nearby conductive parts requires. Induced current may affect electric shock to the human body and malfunction of the electrical equipment. In order to prevent such induced phenomena as a risk factor, shielding is required between the source of the wireless power transmission and the conductive parts. The resonance frequency for the large capacity wireless power transmission has the wavelength of several hundred meters, so most environments are included in the near-field area. By wave impedance, the electric field has higher density in the near-field area and needs to be analyze for protecting. For this purpose, it is necessary to select a substance having a larger electric conductivity and optimized shielding structure. In this paper, an aluminum base shielding structure was presented to conduct experiments on thickness, position, and heat dissipation. In the 35 kW, 60 kHz environments, the optimized 5T Al base shielding structure attenuates the induced current to 43 %.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.461-469
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• 2013

Even though a sewer rehabilitation BTL project has been executed throughout the nation with the input of a significant amount of budget, the overall review on effectiveness of the project is insufficient. And disputes over effectiveness of the project and of the employment of I/I indexes for evaluation of the project are continued due to reliable issues of flux data which has been measured after completion of certain projects and excessive amounts of I/I. Thus, this study has reviewed effectiveness of the project, current status and problems of the installation of fixed flow meters as well as countermeasures based on 15 projects subject to the operation performance evaluation after the completion of the project. The review on operation of the project has revealed that sewer rehabilitation BTL projects are significantly effective and highly effective on reducing a rate of infiltration water. The review on the employment of proper countermeasures for main issues revealed during the investigation on the installation and operation of fixed flow meters has shown that such countermeasures could result in securing more reliable flux data.

• Smart Structures and Systems
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• v.4 no.2
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• pp.221-232
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• 2008

This paper represents the final results of a research program sponsored by the European Commission through project WIND-CHIME ($\underline{W}$ide Range Non-$\underline{IN}$trusive $\underline{D}$evices toward $\underline{C}$onservation of $\underline{HI}$storical Monuments in the $\underline{ME}$diterranean Area), in which the possibility of using advanced seismic protection technologies to preserve historical monuments in the Mediterranean area is investigated. In the current research, the dynamic characteristics of two outstanding Mamluk-Style minarets, which similar minarets were reported to experience extensive damage during Dahshur 1992 earthquake, are investigated. The first minaret is the Qusun minaret (1337 A.D, 736 Hijri Date (H.D)) located in El-Suyuti cemetery on the southern side of the Salah El-Din citadel. The minaret is currently separated from the surrounding building and is directly resting on the ground (no vaults underneath). The total height of the minaret is 40.28 meters with a base rectangular shaft of about 5.42 ${\times}$ 5.20 m. The second minaret is the southern minaret of Al-Sultaniya (1340 A.D, 739 H.D). It is located about 30.0 meters from Qusun minaret, and it is now standing alone but it seems that it used to be attached to a huge unidentified structure. The style of the minaret and its size attribute it to the first half of the fourteenth century. The minaret total height is 36.69 meters and has a 4.48 ${\times}$ 4.48 m rectangular base. Field investigations were conducted to obtain: (a) geometrical description of the minarets, (b) material properties of the minarets' stones, and (c) soil conditions at the minarets' location. Ambient vibration tests were performed to determine the modal parameters of the minarets such as natural frequencies and mode shapes. A $1/16^{th}$ scale model of Qusun minaret was constructed at Cairo University Concrete Research Laboratory and tested under free vibration with and without SMA wire dampers. The contribution of SMA wire dampers to the structural damping coefficient was evaluated under different vertical loads and vibration amplitudes. Experimental results were used along with the field investigation data to develop a realistic 3-D finite element model that can be used for seismic risk evaluation of the minarets. Examining the updated finite element models under different seismic excitations indicated the vulnerability of such structures to earthquakes with medium to high a/v ratio. The use of SMA wire dampers was found feasible for reducing the seismic risk for this type of structures.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.1
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• pp.140-151
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• 2001

This study based on the theoretical understanding of multi-layer planting which have engineering, ecological and landscape benefits, was conducted to find out the status of multi-layer planting in the apartment and neighborhood park in Seoul. This study was also aimed to seek for the problematic matters, and suggest a solution on the current multi-layer planting. The results of this study were as follows; 1) Since landscape woody plants have been classified just as tree and shrub in Korea, the classification for the multi-layer planting has been unreasonable, and landscape woody plants might have been classified as tree, sub-tree and shrub, or upper, middle, and lower-layer, It could be defined that upper layer is over eight meters in full growth, middle over 3-8 meters and lower under 3 meters. 2) In apartments, the upper layer consisted of eighteen species, the middle and lower layer seven species each. In neighborhood parks, the upper layer consisted of fifteen species, and the middle and lower layer five species each. 3) In terms of planting year of the surveyed areas, there were no differences in the number of species when planting year of the apartment was divided into two groups, the first half(1900-1995) and the second(1996-2000). But, in terms of individual occupation, the percentage was decreased in upper layer, while there was increasing in middle and lower layer. 4) As the result of survey of multi-layered area, it appeared that apartment was shown 0.65 percent and neighborhood park 0.61 percent of the planted area, which was less than 1 percentage of landscape architecturally planted area. 5) In apartment, the number of individual in middle layers has been increased in the first half and the second, but with respect to the correlation with multi-layered area, the apartments had the "$\rho$=0.208", saying that increasing middle layer was scattered planting instead of multi-layered planting. 6) In planting at the apartments in Korea, the planting density was limited, because the layer division was restricted to only tree and shrub. On the contrary, it was divided into upper, middle and lower tree in Japan. Therefore, in Korea, it should be classified as the planting density by dividing into tree, sub-tree, and shrubs, or upper, middle and lower tree by the law. And, it should be considered that the multi-layered planting has a proper organic relation as well as the planting density.g density.

• Journal of Korean Society of Transportation
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• v.30 no.2
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• pp.67-78
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• 2012

The current traffic regulations in Korea stipulate that traffic should keep to the right according to the Road Traffic Act; thus, customarily, the 'seat-on-the-left' system has been maintained. However, an increased number of 'seat-on-the-right' vehicles are being imported via a variety of routes from foreign countries, especially from Japan. According to the data from July 2004, 1,343 cargo vehicles and 593 passenger vehicles (for diplomats, etc.) were currently being driven on domestic road. As these 'seat-on-the-right' vehicles are not compatible with the domestic transportation system of driving on the right side of the road, there is a high risk of accidents. Experiments show that such system-driver mismatch causes longer operation time for directional signals, higher error frequency in yielding due to additional mental adjustments for 'seat-on-the-right' vehicle drivers. These are, therefore, influential factors which can lead to possible accidents. Furthermore, when the experiments test the visual range during overtaking maneuvers, the visual range of the drivers in the 'seat-on-the-left' vehicle was 2.95 meters as opposed to 1.7 meters for the drivers in the 'seat-on-the-right' vehicle. (In the experiment, the drivers were instructed to look at the paper cup 10 meters away from the back of drivers' seat.) The results demonstrate that it is necessary to have additional safety measures be implemented for the 'seat-on-the-right' vehicles.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.6
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• pp.40-44
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• 2014

In this paper, maximum power is the lowering device using the facility's energy use and peak load electricity through analyzing attitude should like to make it reduce its power base rate. Simulator to manage the demand for power, a maximum electric power base power from electronic watt-hour meters by a device's signal, predictive power, the current power by computing the goal of power for less than Maximum peak power and peak shift, so that you can manage, and peak York, which role you want a cut Metal heat treatment result which analyzes the data, demand for electricity company over the years of analyzing the characteristics of each load, and effects and Reducing power consumption device every month identified seven Sequence control to the load system and successful power control is about showing that the defined goals.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.12
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• pp.1730-1736
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• 2015

This paper presents a 16-channel transimpedance amplifier (TIA) array implemented in a standard $0.18-{\mu}m$ CMOS technology for the applications of panoramic scan LADAR (PSL) systems. Since this array is the front-end circuits of the PSL systems to recover three dimensional image for unmanned vehicles, low-noise and high-gain characteristics are necessary. Thus, we propose a voltage-mode inverter TIA (I-TIA) array in this paper, of which measured results demonstrate that each channel of the array achieves $82-dB{\Omega}$ transimpedance gain, 565-MHz bandwidth for 0.5-pF photodiode capacitance, 6.7-pA/sqrt(Hz) noise current spectral density, and 33.8-mW power dissipation from a single 1.8-V supply. The measured eye-diagrams of the array confirm wide and clear eye-openings up to 1.3-Gb/s operations. Also, the optical pulse measurements estimate that the proposed 16-channel TIA array chip can detect signals within 20 meters away from the laser source. The whole chip occupies the area of $5.0{\times}1.1mm^2$ including I/O pads. For comparison, a current-mode 16-channel TIA array is also realized in the same $0.18-{\mu}m$ CMOS technology, which exploits regulated-cascode (RGC) input configuration. Measurements reveal that the I-TIA array achieves superior performance in optical pulse measurements.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.2
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• pp.5-15
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• 2008

Cooperation between the GVWS within a few hundred meters has forced MWRs equipped to have service ranges in such a short ranges as well as the limited numbers of channels are available. This kind of situation often produces the frequency interferences between MWRs due to the easy uses of the common and adjacent frequencies between them. Current work provides the details of the frequency interferences and the possible degrees of detections. It is also described that the effective distances for the operation between the GVWS are investigated when they use the common and the adjacent frequencies each other with the factors as the frequency intervals and the antenna arrangement angles.