• Journal of the Korean Physical Society
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• v.73 no.10
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• pp.1589-1595
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• 2018

Similarity index measures the topological proximity of node pairs in a complex network. Numerous similarity indices have been defined and investigated, but the dependency of structure on the performance of similarity indices has not been sufficiently investigated. In this study, we investigated the relationship between the performance of similarity indices and structural properties of a network by employing a two-state random network. A node in a two-state network has binary types that are initially given, and a connection probability is determined from the state of the node pair. The performances of similarity indices are affected by the number of links and the ratio of intra-connections to inter-connections. Similarity indices have different characteristics depending on their type. Local indices perform well in small-size networks and do not depend on whether the structure is intra-dominant or inter-dominant. In contrast, global indices perform better in large-size networks, and some such indices do not perform well in an inter-dominant structure. We also found that link prediction performance and the performance of similarity are correlated in both model networks and empirical networks. This relationship implies that link prediction performance can be used as an approximation for the performance of the similarity index when information about node type is unavailable. This relationship may help to find the appropriate index for given networks.

• Journal of Broadcast Engineering
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• v.15 no.6
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• pp.749-756
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• 2010

The signal space diversity is one of the promising transmission techniques in next generation mobile TV service. However, DVB-T2 does not consider the multiple antennas (MIMO) so that the cyclic Q-delay method, a component interleaver in DVB-T2, causes a critical issue in detecting symbols at the receiver side by increasing the inter-symbol dependency. To solve this problem, the component-swapping technique is proposed, which limits the inter-symbol dependency in order to reduce detection complexity. In this paper, the achievable gain of a component-swapping technique combined with 16K LDPC code defined in DVB-T2 is evaluated by computer simulations. From the results, the gain is confirmed in terms of BER and receive complexity compared to legacy component interleaver methods.

• Journal of KIISE
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• v.41 no.9
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• pp.707-714
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• 2014

In general, the benign apps transmit privacy information to the external to provide service to users as the malicious app does. In other words, the behavior of benign apps is similar to the one of malicious apps. Thus, the benign app can be easily manipulated for malicious purposes. Therefore, the malicious apps as well as the benign apps should notify the users of the possibility of privacy information leakage before installation to prevent the potential malicious behavior. In this paper, We propose the method to detect leakage of privacy information on the android app by analyzing API inter-dependency and shortest distance. Also, we present LeakDroid which detects leakage of privacy information on Android with the above method. Unlike dynamic approaches, LeakDroid analyzes Android apps on market site. To verify the privacy information leakage detection of LeakDroid, we experimented the well-known 250 malicious apps and the 1700 benign apps collected from Android Third party market. Our evaluation result shows that LeakDroid reached detection rate of 96.4% in the malicious apps and detected 68 true privacy information leakages inside the 1700 benign apps.

• Journal of Science and Technology Studies
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• v.3 no.2 s.6
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• pp.29-60
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• 2003

Inter-Korean Cooperation in Science and Technology will contribute to building the trust between S.K and N.K as a leading factor and cut down the cost of unification by diminishing the technology lag and the gap of economic level. This study has shown that we can increase the productivity of unified Korea Innovation system if we systematically analyse the present condition of the Inter-Korean Cooperation and promote Inter-Korean Cooperation. In this study, the author analyses the present condition of the Inter-Korean Cooperation with integrated framework of three aspects to clear up the policy of Inter-Korean Cooperation. First, in the national aspect, we make use of the notion of international cooperation and multilateral mechanism of an international organization. Thereafter, we make out the alternatives in the aspects of international relationship and legal and institutional view Second, in the unification aspect, we consider the Inter-Korean Cooperation by the notion of national innovation system. Thereafter, we make out the alternative in the aspect of a phase-dependent approach. Finally, in technology aspect, we consider the Inter-Korean Cooperation by the notion of technology gap, the framework of technology transfer, and technology dependency theory. As a conclusion, through this study, the author have tried to integrate the various theoretical backgrounds. As a result, the author could analyse the present condition of ter-Korean Cooperation in Science and Technology and team a good lesson from it; Therefore, we can use it as a means of evaluation on a cooperation program and prediction for the future status of cooperation.

• Geomechanics and Engineering
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• v.12 no.5
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• pp.831-847
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• 2017

Conventional geotechnical engineering soil binders such as ordinary cement or lime have environmental issues in terms of sustainable development. Thus, environmentally friendly materials have attracted considerable interest in modern geotechnical engineering. Microbial biopolymers are being actively developed in order to improve geotechnical engineering properties such as aggregate stability, strength, and hydraulic conductivity of various soil types. This study evaluates the geotechnical engineering shear behavior of sand treated with xanthan gum biopolymer through laboratory direct shear testing. Xanthan gum-sand mixtures with various xanthan gum content (percent to the mass of sand) and gel phases (initial, dried, and re-submerged) were considered. Xanthan gum content of 1.0% sufficiently improves the inter-particle cohesion of cohesionless sands 3.8 times and more (up to 14 times for dried state) than in the untreated (natural) condition, regardless of the xanthan gum gel condition. In general, the strength of xanthan gum-treated sand shows dependency with the rheology and phase of xanthan gum gels in inter-granular pores, which decreases in order as dried (biofilm state), initial (uniform hydrogel), and re-submerged (swollen hydrogel after drying) states. As xanthan gum hydrogels are pseudo-plastic, both inter-particle friction angle and cohesion of xanthan gum-treated sand decrease with water adsorbed swelling at large strain levels. However, for 2% xanthan gum-treated sands, the re-submerged state shows a higher strength than the initial state due to the gradual and non-uniform swelling behavior of highly concentrated biofilms.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.2
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• pp.188-199
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• 2000

This paper presents an efficient stable logging scheme for the distributed shared memory system based on the lazy release consistent memory model. In the proposed scheme, inter-process dependency is traced and stable logging is performed when the dependency relation between processes actually happens. With the dependency tracking, the proposed scheme requires much less frequency of stable logging, comparing with the previous schemes in which stable logging is performed whenever any information transfer happens between processes. Also, in the proposed scheme, every data item accessed by a process is not logged, but only the access information is logged in the stable storage. For the recovery from a failure, the correct version of the accessed data items can be effectively traced by using the logged access information. As a result, the amount of logged information is also reduced.

• Journal of Korean Academy of Nursing
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• v.40 no.1
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• pp.110-118
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• 2010

Purpose: To develop outcome indicators of urinary incontinence to measure quality of care in long term care hospitals in Korea. Methods: The draft indicators of urinary incontinence were developed from a literature review and clinical expert panel. A survey of medical records of 280 patients in 20 hospitals was conducted to test inter-rater reliability. Statistical analysis was done to test risk adjustment criteria, variation between hospitals, and stability of indicators, using assessment data from 77,918 patients in 623 hospitals. Results: The inter-rater reliability of items was high (Kappa range: 0.66- 0.92). Severe cognitive impairment (odds ratio [OR]: 3.15, confidence interval [CI]: 3.03-3.26) and total mobility activities of daily living (ADLs) dependency (OR: 4.85, CI: 4.72-4.98) increased the prevalence of urinary incontinence, thus they proved to be significant criteria to stratify high and low risk groups. The prevalence for low risk showed more substantial variation than the high risk group. The indicators were stable over one month. Conclusion: This study demonstrated the feasibility of outcome indicators of urinary incontinence. Improving the reliability of the patient assessment tool and refining the indicators through validation study is a must for future study.

• Journal of Communications and Networks
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• v.10 no.3
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• pp.351-361
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• 2008

This paper presents a delay-margin based traffic engineering (TE) approach to provide end-to-end quality of service (QoS) in multi-protocol label switching (MPLS) networks using differentiated services (DiffServ) at the link level. The TE, including delay, class, and route assignments, is formulated as a nonlinear optimization problem reflecting the inter-class and inter-link dependency introduced by DiffServ and end-to-end QoS requirements. Three algorithms are used to provide a solution to the problem: The first two, centralized offline route configuration and link-class delay assignment, operate in the convex areas of the feasible region to consecutively reduce the objective function using a per-link per-class decomposition of the objective function gradient. The third one is a heuristic that promotes/demotes connections at different links in order to deal with concave areas that may be produced by a trunk route usage of more than one class on a given link. Approximations of the three algorithms suitable for on-line distributed TE operation are also derived. Simulation is used to show that proposed approach can increase the number of users while maintaining end-to-end QoS requirements.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.7 no.1
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• pp.42-59
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• 2000

This study was done to analyze and develop the concept of coping in patients receiving hemodialysis. The Hybrid Model of concept development was applied to develop a conceptual structure of coping in patients receiving hemodialysis, which included a field study carried out using an in-dept interview with 18 patients in the hemodialysis room of one general hospital in Seoul. Data-analysis was done in three phases as suggested by the Hybrid Model. Finally, by summarizing the results from each case, the attributes of coping, its dimensions, definition and structure were outlined. According to the results of the study, a conceptual structure of coping which centers around stressors, stress-appraisal, strategy of coping and new definitions of coping in patients receiving hemodialysis was suggested : The coping of patients receiving hemodialysis is a process that deals with physical, emotional, inter-personal, and role stress caused by hemodialysis due to renal failure. It has a series of phases which include a phase that appraises the stressful situation based on past experience of chronic disease management, one's remaining rears, the extent of family support, the extent of economic dependency, inter-personal support. education and uncertainty, and a phase of developing coping strategies that con be affected by social support and self esteem. As a result of coping, patients adapt or not to the life situation of receiving hemodialysis.

• 한국연소학회:학술대회논문집
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• 2007.05a
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• pp.47-53
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• 2007

The laminar combustion characteristics of interacting coal particles in a convective flow are numerically investigated at particle arrangement and size difference. The numerical simulations, which use the two-step global reaction model to account for the surrounding gas effect, show the detailed interaction among the inter-space particles, undergoing devolatilization and subsequent char burning. Several parametric studies, which include the effect of the gas temperature (1700 K), high pressure(10 atm) and variation in geometrical arrangement of the particle diameter on the volatile release rate and the char combustion rate, have been carried out. The comparison indicates that the shift to the multiple particle arrangement resulted in the substantial change of the combustion characteristics and that the volatile release rate of the interacting coal particles exhibits a strong dependency on the particle spacing and size difference.