• The KIPS Transactions:PartD
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• v.14D no.3 s.113
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• pp.355-362
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• 2007

With development of mobile communications terminal and expansion of mobile Internet, a large number of users can use mobile web contents at anytime and anywhere and will demand service of greater contents. Due to such demand, many studies are being carried out on transcoding contents so that wired web contents can be used in mobile web. However, transcoding and creation of mobile web contents involve difficulties because specifications available from telecommunications companies and mobile terminals have not been standardized. Especially, in order for serving dynamic object of wired web page contents to dynamically change according to time or user, it is required not only to program scripts to suit each terminal, but also to transcode the resources used in advance. for solution to this problem, this study uses the hierarchy structure of DOM (document object model) to display structural characteristics of wired web page. In other words, this study proposes the following technique. Wired web pages are analyzed and the results are established as data structure. Then, dynamic object is extracted and the domain is indexed so that, when serving mobile web page, information can be extracted at the indexed position to create mobile web contents for service on real-time basis. Also, this study aims at developing an editing device to edit mobile web contents and mobile web service server to service the edited contents by applying the above technique.

• The Journal of Society for e-Business Studies
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• v.18 no.4
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• pp.45-65
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• 2013

A design file can get larger in size as the complexity of the target object increases. A large design file may reside in a large parallel computing system, such as cloud computing systems, and many designers may work concurrently on the same design file. In such a case, it is obvious that we need some kind of protection mechanism so that each user can access only the area of the file he or she is entitled to. Two approaches can be taken for this problem: one is the traditional access control mechanisms and the other encryption techniques. We take the latter approach to ensure the safety of the file even in public domain such as clouding systems, and in this paper, we suggest an encryption scheme for a file where the file is encrypted in multi-layer so that each user is allowed to access the file only at the layer for which the user has the proper access right. Each layer of the file is encrypted with different keys and these keys are exposed only to those who have the right access permit. The paper explains the necessary file format to achieve this goal and discusses the file manipulation functions to handle this new file format.

• Journal of the Korean earth science society
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• v.32 no.6
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• pp.613-628
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• 2011

Restoration, prediction and noise analysis of geomagnetic data measured in the Korean Peninsula were performed. Restoration methods based on an optimized principal component analysis (PCA) and the geostatistical kriging approach were proposed, and its effectiveness was also interpreted. The PCA-based method seemed to be effective to restore the periodical signals and the geostatistical approach was stable to fill the gaps of measurements. To analyze the noise level for each observatory, the geomagnetic time-series was plotted by scattergram which reflects the spatial variation, using data observed during same period. The scattergram showed that the observation made at Cheongyang seemed to have better quality in spatial continuity and stability, and the restoration result was also better than that of Icheon site. For the restoration, both of the methods, geostatistical and optimizaed PCA, showed stable result when the missing of observation was within 20 points. However, in case of more missing observations than 20 points and prediction problem, the optimized PCA seemed to be closer to the real observation considering the frequency-domain characteristics. The prediction using the optimized PCA seems to be plausible for one day of period for interpretation.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.9
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• pp.1028-1036
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• 2008

In the OFDM system, IQ imbalance problem happens at the RF front-end of transceiver, which degrades the BER(bit error rate) performance because it affects the constellation in the received signal. Also, phase noise is generated in the local oscillator of transceivers and it destroys the orthogonality between the subcarriers. Conventional PNS algorithm is effective for phase noise suppression, but it is not useful anymore when there are jointly IQ(In-phase and Quadrature) imbalance and phase noise. Therefore, in this paper, we analyze the effect of IQ imbalance and phase noise generated in the down-conversion of the receiver. Then, we estimate and compensate the IQ imbalance and phase noise at the same time. Compared with the conventional method that IQ imbalance after IFFT is estimated and compensated in front of FFT via the feedback, this proposed method extracts and compensates effect of IQ imbalance after FFT stage. In case IQ imbalance and phase noise exist at the same time, we can decrease complexity because it is needless to use elimination of IQ imbalance in time domain and training sequences and preambles. Also, this method shows that it reduces the ICI and CPE component using adaptive forgetting factor of MMSE after FFT.

• IMMUNE NETWORK
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• v.3 no.2
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• pp.103-109
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• 2003

Background: As all HLA class II genes, the DQ genes show their polymorphic variation mainly in the second exon, which encodes the first extracellular domain of the molecule. PCR-SSOP (Polymerase chain reaction-Sequence specific oligonucleotide probe) techniques were frequently used for HLA-DQA1 and DQB1 typing but certain alleles, $DQA1^*0101/0104/0105$, $^*302/0303$, $*0501/0505$ and $DQB1^*0201/^*0202$ which differ from each other in segment other than exon 2, could not be unequivocally assigned. Methods: To overcome this problem, we applied additional PCR-SSP (PCR-Sequence specific primer) method to analyze DQA1 exons 1, 3 and 4 and DQB1 exon 3. And we investigated the distributions and haplotypes of HLA-DRB1, DQA1 and DQB1 alleles in 406 unrelated Korean healthy individuals. Results: Using this method the indistinguishable alleles of DQA1 and DQB1 in PCR-SSOP were typed definitively. We also found several important associations between DQA1 and DQB1 alleles in the Korean population; $DQA1^*0101-DQB1^*0501$, $DQA1^*0104-DQB1^*0502$ or $-^*0503$, $DQA1^*0105-DQB1^*0501$, $DQA1^*0302-DQB1^*0303$, $DQA1^*0303-DQB1^*0401$ or $-^*0402$, $DQA1^*0501-DQB1^*0201$, $DQA1^*0505-DQB1^*0301$, and $DQA1^*0201-DQB1^*0202$. The haplotypes of DRB1-DQA1-DQB1 associated with $DQA1^*01$, $^*03$, $^*05$, and $DQB1^*02$ subtypes were investigated. Several haplotypes associated with these alleles were observed in the Korean population. Conclusion: Our results can be helpful to find potential unrelated donors for bone marrow registries and study the HLA-associated disease and anthropology at high-resolution allelic level.

• Asia pacific journal of information systems
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• v.18 no.2
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• pp.73-94
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• 2008

When individuals collaborated in virtual settings, communication is medicated through a variety of communication technologies, and is associated not only with communication effectiveness but also with socio-emotional interactions among group members. In this regards, scholars have examined how technology-mediated communication systems can be designed and used to facilitated communication interaction. However, the empirical results of the previous studies have revealed inconsistencies in the effects of communication media on users' behavioral or attitudinal responses, and on their viable effectiveness in organizations. Some studies claim that computer-mediated communication(CMC) is task-oriented but not suitable for emotional expression since it hinders close interpersonal interaction. On the other hand, some studies argue that individuals are able to develop interpersonal relationships more effectively in a CMC environment than in an FtF-environment. Due to the different perspectives, a theoretical gap exists, and it leads to the inconsistent research findings. The purpose of this paper is to combine the two different perspectives into single unified model, thereby providing a more realistic and comprehensive understanding about virtual collaboration. The present study here sought to answers the following questions with organizational communication perspective: What are the major components of virtual collaboration? What factors affect the performance of virtual collaboration? And what kind of managerial efforts should organization make in order to facilitate CMC media effectiveness in virtual collaboration? Although there is a certain belief that new media, namely technology-mediated communication support would create new opportunities, the problem of "how" or "why" has been an important question that is still not fully addressed. In this regards, we collectively reexamined previous literatures with major issues which are still controversial and integrated various theoretical activity within computer-mediated communication domain: task-oriented approach, socio-emotional approach, and evolutionary psychological approach. Our first contribution is to develop a framework for virtual collaboration by combining two different perspectives into a single unified model, providing a more realistic and comprehensive understanding. The second main contribution is the joint modeling of both social presence and cognitive effort, and the effects on two distinct but important communication outcomes(i.e., take performance and relational development). We tested the research hypotheses which were developed based on the various CMC theories using data gathered through a self-administered mail survey of 127 individuals of 69 virtual workgroups. The proposed model was supported, providing preliminary evidence that the tension between two opposite view should be integrated. The results show that the individual's psychological processes(social presence and cognitive effort) in a virtual environment significantly mediated the effect of CMC inputs (media richness, user adaptation, and shared contest) on the CMC outputs (task performance and relational development). Furthermore, this study shows that the lack of perceived media richness of CMC media can be complemented by user adaptation and shared context. Based on the results, we discuss how communication system should be designed and implemented so as to promote virtual interaction as well as how a virtual workgroup should be composed to complement the lack of media richness. A virtual collaboration using CMC media may create new value by overcoming the logistical constraints. On the other hand, it may also generate various managerial risks such as communicational depersonalization, process dissatisfaction, and low cohesion. Therefore, this study suggests that organization managers should carefully choose the CMC mediums and monitor individual member's cognitive and affective psychological processes during virtual collaboration to reduce potential risks in virtual collaboration.

• Spatial Information Research
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• v.18 no.1
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• pp.19-26
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• 2010

It is important to manage the underground facilities efficiently because they are directly related to the convenience and safety of citizens. But the fact that the different agencies take on a role of managing the underground facilities respectively makes it impossible. So Korean government has exerted great efforts to solve this problem through several projects. Korean government expects that the ubiquitous technologies such as sensor and wireless communication in the domain of the underground facilities management will be useful. It is main duty of u-City Management Center to monitor several situations about the underground facilities using ubiquitous technologies. But there is no consensus about what concrete situations it has to monitor even though u-cities under construction. Because local governments or related companies are in charge of carrying out these roles yet, there is no legal basis on which to do these tasks by the center. And it is needed to develop new technologies for u-services efficiently. Because technologies for u-service are vast, various and converged, so it necessary to develop them according to priority or in cooperation with other developers. In this paper, we classify the monitoring items for each facility which were investigated by a recent research. It is expected to make use of defining the role of the center and developing technologies with u-service.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.25-38
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• 1996

To investigate the stability problem of irrigation-drainage channel excavation slope on soft ground, analyzed the behavior of the soft ground with excavation slope by the limit equilibrium method and the finite element method, and compared with field tests. The results of this study were summarized as follows; 1. When rapid drawdown the water level, the crack was occurred by the effect of the excess pore water pressure, and the pore water pressure was decreased slowly. 2. As the width of excavation was larger, the crack width was larger. And, excavated depth was deeper, the progressive failure was appeared. 3. When the soft ground excavation was small-scale, the minimum safety factor was more effected by cohesion(1.0, 1.5, 2.0, 2.5, 3.0) than excavated slope inclination(1:l, 1:1.5, 1:2). 4. As excavation was progressed, the settlement occurred on the top-slope due to plastic domain, and heaving was occurred at the bottom of excavation. 5. The maximum shear stress was appeared greatly as the base part of slope went down. Because of the increase of the maximum shear stress, tension area occurred and local failure possibility was increased. 6. As the excavation depth was increased, the maximum shear strain was appeared greatly at the base of slope and distribution pattern was concentrated beneath the middle of slope.

• Journal of Digital Convergence
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• v.15 no.8
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• pp.455-463
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• 2017

Background/Objectives: The purpose of the study is to derive a goal usable in the field by exploring the case management success experiences of case managers. Civil case managers state that what is still important in case management practice is qualitative change made in the practice process. Therefore, the study will deal with detailed contents about case management that civil domain case managers consider to be important. Methods/Statistical analysis: For data collection, the study used focus group interview on 20 professional case management social workers and used Grounded theory method by Glaser for data analysis. The analysis of collected data consisted of a process of finding the categories and characteristics of the research problem. Findings: As a result of analysis, 4 categories, 10 subcategories, and 25 elements were derived for success experiences of case management practice. The categories were divided into satisfaction and ability improvement of client, case manager ability improvement, establishment of organization and environment function, and multilateral trust relationship strengthening. Improvements/Applications: The results of this study further clarified the goal of field case management practice and it was suggested as a plan to reflect on future case management related institutions evaluation.

• Geophysics and Geophysical Exploration
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• v.7 no.2
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• pp.136-147
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• 2004

In this study, the characteristics of magnetotelluric (MT) responses due to a three-dimensional (3-D) body are analyzed with 3-D numerical modeling. The first model for the analysis consists of a single isolated conductive body embedded in a resistive homogeneous half-space. The second model has an additional conductive overburden while the other conditions remain the same as the first one. The analysis of apparent resistivities shows well that the 3-D effects are dominant over some frequency range for the first model. Two mechanisms, current channeling and induction, for secondary electric fields due to the conductive body are analyzed at various frequencies: at high frequencies induction is more dominant than channeling, while at low frequencies channeling is more dominant than induction. Tippers have a strong relation to the position of anomalous body and the real and imaginary parts of induction vector also indicate the position of anomalous body. off-line conductive anomaly sometimes causes severe problem in 2-D interpretation. In such case, induction vector analysis can give information on the existence and location of the anomalous body. Each parameter of the second model shows similar responses as those of the first model. The only difference is that the magnitude of all parameters is decreased and that the domain showing the 3-D effects becomes narrower. As shown in this study, the analysis of 3-D effects provides a useful and effective means to understand the 3-D subsurface structure and to interpret MT survey data.