• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.1
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• pp.48-59
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• 2009

Next generation mobile communication system will have various access networks and provide seamless multimedia data service to mobile nodes. The WiNGS system, one of these access network, has superior RAT(Radio Access Technology) and network connectivity other than previous ones. In this paper, we propose link-layer SR-ARQ between mobile node and WAGW to solve packet re-ordering problem during handover. In the proposed scheme, we apply the adaptive timer at the SR-ARQ sender to reduce unnecessary packet retransmission during handoff and delayed NAK algorithm at the SR-ARQ receiver for delaying NAK response due to temporary out-of-sequenced frames. We evaluate the performance of the proposed scheme by implementing the new SR-ARQ protocol at the link-layer using ns-2 simulator, and show the handover performance is improved greatly by preventing unnecessary retransmission.

• Journal of Digital Convergence
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• v.12 no.4
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• pp.51-68
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• 2014

Today's public sector information is considered an important national asset that has social and economic value. Hence, developed countries are competitively promoting various policies to actively promote access to public sector information and the use of such information for private purposes. The Korean government is also boosting the Government 3.0 policy as a new governmental management paradigm that supports the creative economy. Despite these governmental efforts, since open public sector information is only classified from the supplier's perspective, it is difficult to have access to information for private application from the consumer's perspective and expand private applications because of the problems in identifying the information source. In this study, the concept of data from the user's perspective for the activation of private applications was defined by focusing on public sector information obtained by affiliated organizations of the Ministry of Science, ICT and Future Planning(MSIP). The new classification system was designed by analyzing the classification system of conventional open services of public sector information through investigation.

• The Journal of Society for e-Business Studies
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• v.13 no.3
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• pp.121-135
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• 2008

Railroad logistics transporting freight by train takes charge of 10 or 20 percent of domestic cargos. Railroad logistics users such as transport companies including shippers or Inland Container Depot(ICD) use electronic document(EDI or XML) or input data through WEB to process railroad logistics business. However, as business environments evolving into e-business, it is required to upgrade the legacy railroad logistics process. As the increase of using ebXML-based schema format, it is also needed to improve the electronic documents based on DTD format into those of XML schema format. This study deals with information standard for railroad logistics to improve the railroad logistics business. To this purpose railroad business processes were re-defined through the standard business process modeling methodology. Information model was also derived by defining railroad logistics activities from business process model. And Business Information Entities(BIEs) were defined to design new electronic documents according to the extracted information model. An improved system architecture for railroad logistics was proposed as well. The results of this study will provide an effective and flexible business flow to railroad logistics business.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.3
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• pp.295-305
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• 2011

In this study, a seismic behavior of electrical cabinet system in Nuclear Power Plants(NPPs) was evaluated by the shaking table test. A 480V Motor Control Centers(MCCs) was selected for the shaking table test, and a real MCC cabinet for the Korea Nuclear Power Plant site was rented by manufactured company. For the shaking table tests, three kinds of seismic input motions were used, which were a US NRC Reg. guide 1.60 design spectrum, a UHS spectrum and PAB 165' floor response spectrum(FRS). Especially, the UHS input motion was selected for an evaluation of structural seismic amplification effects, three directional accelerations were measured at three points outside on the cabinet system and also that of the incabinet response amplification, accelerations were measure at two points which were mounted in electrical equipment such as relay. Seismic amplification effect is determined at the outside and inside of a cabinet as input seismic motion, and compared to the results which are calculated by analytical method based on NUREG/CR-5203.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.3
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• pp.1-10
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• 2011

Social network service is defined as an online service or communication service based on social relations among people applied the concept of social network. Social collaborative service included in social network service is characterized by the new value of modified content or recreated content made through collaborative creation process between members of the group. It has the remarkable merits such as sharing and collaboration. But, at the same time, it has the latent problems such as content reuse or copy that is not allowed for members to use. It has been emerged that UCC which is a typical example of recreated or modified content has the copyright issues in both creation and publishing step. To resolve this matter, we don't have many appropriate methods except CCL so far. So, in this paper, we define the problem and implement the UCC metadata manager to control metadata reflecting the feature of UCC. We draw the reference metadata element to identify original content utilized re-creation process. After that we define the R.Metadata Loader module based on the use case. Finally, the proposed UCC metadata manager provides the information of referenced content and lets us to identify the relationship between reference contents. So as to implement prototype, we use Kaltura which is CMS using open source and obtain functional extensibility of metadata manager by using open API.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.240-244
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• 2013

Although forward osmosis desalination technology has drawn substantial attention as a next-generation desalination method, the energy efficiency of its draw solution treatment process should be improved for its commercialization. When ammonium bicarbonate is used as the draw solute, the system consists of forward-osmosis membrane modules, draw solution separation and recovery processes. Mixed gases of ammonia and carbon dioxide generated during the draws solution separation, need to be recovered to re-concentrate ammonium bicarbonate solution, for continuous operation as well as for the economic feasibility. The diluted ammonium bicarbonate solution has been proposed as the absorbent for the draw solution regeneration. In this study, experiments are conducted to investigate performance and features of the absorption corresponding to absorbent concentration. It is concluded that ammonium bicarbonate solution can be used to recover the generated ammonia and carbon dioxide. The results will be applied to design and operation of pilot-scale forward-osmosis desalination system.

• Journal of Distribution Science
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• v.12 no.4
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• pp.73-83
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• 2014

Purpose - This study aims to classify and extend the consumer value of movie theaters into various values such as functional value, emotional value, social value, epistemic value, and conditional value based on the theory of consumption value by Sheth, Newman and Gross (1991). It also aims to verify the path structure of consumption value→customer satisfaction→behavior intention of movie theaters to confirm its generalization. Research design, data, and methodology - This study was conducted by collecting data on Kimpo university students from various areas in Incheon, Northern Seoul, Ilsan, Kyonggi Province, and Kimpo City. The survey was conducted by distributing 280 survey papers from Oct. 5 to 15, 2013 and collecting 238 of them. The final analysis used 208 questionnaires, after excluding 30 invalid responses. The statistical analysis of this study used the SPSS 19.0 statistics package. Results - The results of the survey are as follows: First, consumption values of movie theaters are classified into the following five groups: functional value, emotional value, social value, epistemic value, and conditional value. This study verified that consumption values play a role as a previous variable of customer satisfaction. Second, functional value, emotional value, and epistemic value have positive effects on customer satisfaction. On the other hand, social value and conditional value do not affect customer satisfaction. Finally, customer satisfaction has a positive impact on behavior intention. Theater users have an intention to re-use or recommend the movie theater they used when they are satisfied with a movie theater's physical environment and services. Conclusions - This study can provide academic and practical implications as follows based on the results mentioned above. First, academic implications can be found in that consumption values of movie theater users are classified into five values based on the theory of consumption value by Sheth et al. (1991). In the previous study, the service quality of a movie theater was studied based on the service quality of service encounters and a physical environment→customer satisfaction→behavior intention path structure. However, this study was verified by a consumption value→customer satisfaction→behavior intention path structure to classify consumption value, but not service quality or perceived value of quality, to confirm this generalization. Second, practical implications can be found in that the relative impact of consumption value of movie theaters on consumer satisfaction showed that functional value was followed by epistemic value and emotional value. In the previous study on movie theaters, previous variables of customer satisfaction were separated only by functional service quality including service encounters and physical environment; in some other studies, quality of service encounter had a direct effect on customer satisfaction. Accordingly, a marketing manager of a movie theater should develop various differentiated services by reflecting not only functional value such as service encounters and physical environment but also epistemic value and emotional value.

• Management & Information Systems Review
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• v.34 no.1
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• pp.1-20
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• 2015

This study analyses the relationship with the feature of the web usability and Social commerce. Therefore, this research tries to investigate the relationship about in which the characteristic of the web-site usability is connected through the confidence about the Social commerce site to the re-purchase. The existing research that the information system and Electronic commerce relates is considered and the usability factor about the Social commerce site tries to be drawn and these try to verify on the relationship with the trust building of the user about the Social commerce site and purchasing intention through the positive research. The result is follows. First, the visual property of the Social commerce site was confirmed to have the descriptive ability noted to the confidence. Second, it was confirmed to have the descriptive ability that information characteristic about the Social commerce site notes to the confidence. Third, it was confirmed to have the descriptive ability that relative characteristic about the Social commerce site notes to the confidence. The importance of the web-site usuability has preferentially to be considered in being put through this research and building the confidence of the social commerce user could be known. When running with the social commerce site design, this is determined because it can become the useful standard.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.147-155
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• 2012

Aboriginal and Torres Strait Islander people comprise about 2.5% of the Australian population. Cancer registry data indicate that their breast cancer survivals are lower than for other women but the completeness and accuracy of Indigenous descriptors on registries are uncertain. We followed women receiving mammography screening in BreastScreen to determine differences in screening experiences and survivals from breast cancer by Aboriginal and Torres Strait Islander status, as recorded by BreastScreen. This status is self-reported and used in BreastScreen accreditation, and is considered to be more accurate. The study included breast cancers diagnosed during the period of screening and after leaving the screening program. Design: Least square regression models were used to compare screening experiences and outcomes adjusted for age, geographic remoteness, socio-economic disadvantage, screening period and round during 1996-2005. Survival of breast cancer patients from all causes and from breast cancer specifically was compared for the 1991-2006 diagnostic period using linked cancer-registry data. Cox proportional hazards regression was used to adjust for socio-demographic differences, screening period, and where available, tumour size, nodal status and proximity of diagnosis to time of screen. Results: After adjustment for socio-demographic differences and screening period, Aboriginal and Torres Strait Islander women participated less frequently than other women in screening and re-screening although this difference appeared to be diminishing; were less likely to attend post-screening assessment within the recommended 28 days if recalled for assessment; had an elevated ductal carcinoma in situ but not invasive cancer detection rate; had larger breast cancers; and were more likely than other women to be treated by mastectomy than complete local excision. Linked cancer registry data indicated that five-year year survivals of breast cancer cases from all causes of death were 81% for Aboriginal and Torres Strait Islander women, compared with 90% for other women, and that the former had larger breast cancers that were more likely to have nodal spread at diagnosis. After adjusting for socio-demographic factors, tumour size, nodal spread and time from last screen to diagnosis, Aboriginal and Torres Strait Islander women had approximately twice the risk of death from breast cancer as other women. Conclusions: Aboriginal and Torres Strait Islander women have less favourable screening experiences and those diagnosed with breast cancer (either during the screening period or after leaving the screening program) have lower survivals that persist after adjustment for socio-demographic differences, tumour size and nodal status.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.3
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• pp.214-224
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• 2018

Continuous space development increases the occurrence probability of space hazards such as collapse of a satellite and collision between a satellite and space debris. In Korea, a space surveillance network with optical system has been developed; however, the radar technology for an independent space surveillance needs to be secured. Herein, an L-band phased array radar system for the detection and tracking of space objects is proposed to provide a number of services including collision avoidance and the prediction of re-entry events. With the mission analysis of space surveillance and the case analysis of foreign advanced radar systems, the radar parameters are defined and designed. The proposed radar system is able to detect a debris having a diameter of 10 cm at a maximum distance of 1,576 km. In addition, we confirmed the possibility of using the space surveillance mission for domestic satellites through the analysis of the detection area.