• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3D
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• pp.355-361
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• 2011

In order to properly evaluate ITS services exposed in SMART Highway project, a confident dynamic origin-destination (OD) is inevitably needed. This paper used WAVE communication information as a part of call and response (C&R) communication which constitutes core part of the technology for constructing OD. This information includes node information and vehicle information (e.g., latitude and longitude) as well as trajectory data and sample path volume date calculated using node information and vehicle information. A procedure developed to construct a dynamic OD and to validate OD is consist of 1) making toy network and one-hour 00 (random distribution), 2) collecting link information and vehicle information, 3) constructing five-minute OD, and 4) validating estimated OD result using traffic volume and travel time simultaneously. The constructed OD is about 84.79% correct within less than 20% error range for 15min traffic volume, and about 85.42%, within less than 20% error rate of 15 min travel time. Some limitations and future research agenda have also been discussed.

• Journal of the Korean Geographical Society
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• v.34 no.1
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• pp.99-118
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• 1999

This paper aim to grasp the order region distribution of the goods, which are the sobaeksan ganodenma lucldum on the mail-order through post office and the poum jujube on the mail-order through agncultural Co- operalive and the regional connection made by distributing the goods between production region and sale region The amount of sales for sobaeksan ganodenma lucidum, with little regional difference in the producing volume, is not affected by the basic fare of a long-distance call in the spaual sale. It also shows that the amounl of poun jujude with regional difference of production volume is restricted by distance.

• Journal of the Korea Computer Graphics Society
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• v.4 no.1
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• pp.55-66
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• 1998

This paper presents a simple method for relieving the ambiguity problems within the sub-voxel based surface-fitting approach for the surface construction. ECB algorithm is proposed to avoid the ambiguity problem which is the root of the holes within the resulting polygon based approximation. The basic idea of our disambiguation strategy is the use of a set of predefined modeling primitives (we call SMP) which guarantees the topological consistency of resulted surface polygons. 20 SMPs are derived from the extension of the concept of the elementary modeling primitives in the CB algorithm [3], and fit one to five faces of them to the iso-surface crossing a cell with no further processing. A look-up table which has a surface triangle list is pre-calculated using these 20 SMPs. All of surface triangles in the table are from the faces of SMPs and are stored in the form of edge list on which vertices of each surface triangle are located. The resulted polygon based approximation is unique at every threshold value and its validity is guaranteed without considering the complicated problems such as average of density and postprocessing. ECB algorithm could be free from the need for the time consuming post-processing, which eliminates holes by revisiting every boundary cell. Through three experiments of surface construction from volume data, its capability of hole avoidance is showed.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1991.10a
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• pp.174-178
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• 1991

ATM, the core technology of BISDN, provides a high degree of flexibility with regard to varying bandwidth requirements for different services. In ATM networks, since users may exceed the traffic volume negotiated at the call setup, traffic from users may need to be monitored and enforced to comply with traffic parameters. The leakybucket mechanism is one of the typical traffic enforcement methods based on the use of transmission tokens for each cell. In this mechanism the major system parameters are size of input buffer, size of token pool, and token generation ratio. In order to represent ATM cell arrivals we assume a Poisson process. In this paper, a state transition analysis technique is used to study the cell loss rates for various values of system parameters.

• Journal of the Korean Society for Library and Information Science
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• v.3
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• pp.1-24
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• 1973

This paper is intended as a basic study in which the purpose is to provide understanding of the workings of man in relation to his information resources. Such understanding would prove of value in formulating the policies of an inoformation center serving the fields of science and technology. The information problem of the scientific community was assessed in the lights of the characteristics of the information (cumulativeness, currency versus obsolescence, volume versus redundancy, interrelationships, and foreign literature)and the flow of information and communication patterns covering the use of the variety of media and the information gathering habits of scientists. What can be done to ease the problem was sought in the improvements and innovations which call the attentions of the scientists and the technologists as producers and users of the information, of the professional organizations of various disciplines and of government.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.6
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• pp.123-129
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• 2013

Android file system is vulnerable to the external access of system resources via its arbitrary access mode and need user's control for SD and UMS medias due to its open architecture. In response to the device control, there is a drawback that its controlability is valid only in the case of embedded linux kernel with VDC function. Hence the solution is to directly implement VDC through system call, with another security module for device storage than system module being added to android system. In this paper the new method of android storage access control for personal information is proposed via VDC for mount system of storage. The access method for SD and UMS were implemented using VDC and mount mechanism. This access control system has been designed to control the granted users in kernel level if files are flowed out by copying. As a result, it was proved through testing that the access control system has exactly detected the write access operation.

• Journal of Korea Port Economic Association
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• v.38 no.3
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• pp.1-13
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• 2022

The Busan-Ulsan-Gyeongsangmando(BuUlGyeong) megacity aims to grow into the second metropolitan area by strengthening the growth and connectivity of the southeast region in Korea. In order to analyze the linkage between port logistics and regional economic development, this study focused on the economic community of BuUlGyeong. The findings are as follows. First, it was found that vessel entry and departure had a positive (+) significant effect on cargo volume. Second, the cargo volume was found to have a preemptive effect on the vessel entry and exit ports and the composite index. Third, the composite Index was found to have a significant positive (+) effect on cargo volume. From the results of the variance decomposition, it can be confirmed that the composite index has a weak impact on ship entry/exit and cargo volume. Based on the above findings, some policy implications are derived. First, regional governments in BuUlGyeong should provide incentives to revitalize the maritime economy such as the expansion of maritime port infrastructure and encouraging investment. Second, since an increase in cargo transport volume at major national ports linked to the BuUlGyeong region has a positive (+) effect on economy. Therefore it is necessary to expand actively port marketing and regular service for the country and ports. Third, investments should be made continuously to expand the marine port infrastructure such as the expansion of facilities so that global shipping companies can continue to call megacities in BuUlGyeong ports for super-large ships and cruises.

• Electrical & Electronic Materials
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• v.16 no.9
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• pp.64.2-65
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• 2003

A 4 nm layer of ZrOx (targeted x-2) was deposited on an interfacial layer(IL) of native oxide (SiO, t∼1.2 nm) surface on 200 mm Si wafers by a manufacturable atomic layer chemical vapor deposition technique at 30$0^{\circ}C$. Some as-deposited layers were subjected to a post-deposition, rapid thermal annealing at $700^{\circ}C$ for 5 min in flowing oxygen at atmospheric pressure. The experimental x-ray diffraction, x-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and high-resolution parallel electron energy loss spectroscopy results showed that a multiphase and heterogeneous structure evolved, which we call the Zr-O/IL/Si stack. The as-deposited Zr-O layer was amorphous $ZrO_2$-rich Zr silicate containing about 15% by volume of embedded $ZrO_2$ nanocrystals, which transformed to a glass nanoceramic (with over 90% by volume of predominantly tetragonal-$ZrO_2$(t-$ZrO_2$) and monoclinic-$ZrO_2$(m-$ZrO_2$) nanocrystals) upon annealing. The formation of disordered amorphous regions within some of the nanocrystals, as well as crystalline regions with defects, probably gave rise to lattice strains and deformations. The interfacial layer (IL) was partitioned into an upper Si $o_2$-rich Zr silicate and the lower $SiO_{x}$. The latter was sub-toichiometric and the average oxidation state increased from Si0.86$^{＋}$ in $SiO_{0.43}$ (as-deposited) to Si1.32$^{＋}$ in $SiO_{0.66}$ (annealed). This high oxygen deficiency in $SiO_{x}$ indicative of the low mobility of oxidizing specie in the Zr-O layer. The stacks were characterized for their dielectric properties in the Pt/{Zr-O/IL}/Si metal oxide-semiconductor capacitor(MOSCAP) configuration. The measured equivalent oxide thickness (EOT) was not consistent with the calculated EOT using a bilayer model of $ZrO_2$ and $SiO_2$, and the capacitance in accumulation (and therefore, EOT and kZr-O) was frequency dispersive, trends well documented in literature. This behavior is qualitatively explained in terms of the multi-layer nanostructure and nanochemistry that evolves.ves.ves.

• The Journal of the Acoustical Society of Korea
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• v.14 no.2
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• pp.113-122
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• 1995

This paper describes characteristics of a bone conduction telephone which was developed for conductive hearing impaired persons to call without additional devices and results of its performance test. Not only the hearing impaired but also normal hearing persons can use this telephone because we developed a bone conduction vibrator with which they can perceive speech signal using functions of air conductive hearing as well as bone conductive hearing. It also has tone control function compensating hearing losses for the hearing impaired originating from their hearing characteristics, and using this function together with received volume control it has received volume range of 20dB in loudness rating, which is similar effect as what a telephone set with built-in received amplifier has. From results of articulation and intelligibility tests for 19 hearing impaired persons, we can see that if their bone-conduction hearing loss is 61dB or less, they can understand words or sentences and response well with this telephone.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.1
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• pp.101-116
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• 2017

This Study estimates the actual night traffic using the smart card data used by most of the public transportation users, and compares it with the current night bus routes by KT Telecom based on the night time call volume. In order to compare the current night bus and night trips evaluated by smart card data, we presented indicators related to the degree of matching, and estimated the volume of service currently provided. The unique approach of the study is that we chose subway station instead of bus stop for the unit of the study. Bus stops has their complexity in a way that stops with same name could belong to different administrative area depending on its direction. For this reason, we decided to use subway station and defined its adjacent administrative district as the scope of influence. Since night bus is the primary means of transportation during the late night, it is anticipated that they will be able to provide better service by calculating the actual traffic and selecting the routes.