• The Transactions of the Korea Information Processing Society
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• v.7 no.4
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• pp.1184-1192
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• 2000

Multicast has communication mechanism that is able to transfer voice, video for only the specific user group. As compared to unicast, multicast is more susceptive to attack such as masquerading, malicious replay, denial of service, repudiation and traffic observation, because of the multicast has much more communication links than unicast communication. Multicast-specific security threats can affect not only a group's receivers, but a potentially large proportion of the internet. In this paper, we proposed the multicast security model that is able to secure multi-group communication in CBT(Core Based Tree), which is multicast routing. And designed the multicast key distribution protocol that can offer authentication, user privacy using core (be does as Authentication Server) in the proposed model.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.09a
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• pp.13-16
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• 2005

For mass production, usually injection mold has multi-cavity which is filled through geometrical balanced runner system. Despite geometrical balanced runner system, filling imbalances between cavity to cavity have always been observed. These filing imbalances are one of the most significant factors to affect quality of plastic parts when molding plastic parts in multi-cavity injection mold. Filling imbalances are results from non-symmetrical shear rate distribution within melt as it flows through the runner system. It has been possible to decrease filling imbalance by optimizing processing conditions, but it has not completely eliminated this phenomenon during injection molding processing. This paper presents a solution of these filling imbalances through using 'runner core pin'. The runner core pin which is developed in this study creates a symmetrical shear distribution within runner. As a result of using runner core pin, a remarkable improvement in reducing filling imbalance was confirmed.

• Science of Emotion and Sensibility
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• v.26 no.3
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• pp.15-28
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• 2023

This study examined the affective representation and response consistency among individuals using affective videos, a naturalistic stimulus inducing emotional experiences most similar to those in daily life. In this study, multidimensional scaling was conducted to investigate whether the various affective representations induced through video stimuli are located in the core affect dimensions. A cross-participant classification analysis was also performed to verify whether the video stimuli are well classified. Additionally, the newly developed intersubject correlation analysis was conducted to assess the consistency of affective representations across participant responses. Multidimensional scaling revealed that the video stimuli are represented well in the valence dimension, partially supporting Russell (1980)'s core affect theory. The classification results showed that affective conditions were successfully classified across participant responses. Moreover, the intersubject correlation analysis showed that the consistency of affective representations to video stimuli differed with respect to the condition. This study suggests that the affective representations and consistency of individual responses to affective videos varied across different affective conditions.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.1
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• pp.10-19
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• 2006

Statement of problem : The various kinds of properties of post and core may affect the stress distribution to the root of endodontically treated teeth Purpose: To evaluate the influence of various kinds of properties of post and core to the stress distribution to the root of endodontically treated teeth. Material and methods: Mandibular first premolar, prepared by general shape of post and core with gold crown, was used to two dimensional axisymmetric modeling for finite element analysis. Then property values of 8 different kinds of post and core was substituted for each. Finally, stress distribution shown areas around the root of post and core was analysed after applying 50N of vortical and oblique load. Results: 1. Stress value of oblique load was much higher than the maximum stress value of vertical load. 2. Under oblique load, very concentrated stress was located on post periapical area and variations in stress were very severe. Contrary to this, stress distribution was relatively uniform in vertical load. 3. Post materials with higher elastic modulus showed relatively more apically focused stress, and post materials with lower elastic modulus showed stress focused on cervical area on the axial wall of post. 4. Stress change according to the properties of core was shown only in the cervical area of post and below core as the higher elastic modulus, then increased in stress. 5. Post and core with medium value of elastic modulus showed relatively uniform stress distribution. Conclusions: Post materials with higher elastic modulus showed relatively more apically focused stress, and post materials with lower elastic modulus showed stress focused on cervical area on the axial wall of post. Stress change according to the properties of core was shown only in the cervical area of post and below core.

• Steel and Composite Structures
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• v.30 no.2
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• pp.81-96
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• 2019

The behavior of a new Three-Tube Buckling-Restrained Brace (TTBRB) with circumference pre-stress (${\sigma}_{{\theta},pre}$) in core tube are investigated through a verified finite element model. The TTBRB is composed of one core tube and two restraining tubes. The core tube is in the middle to provide the axial stiffness, to carry the axial load and to dissipate the earthquake energy. The two restraining tubes are at inside and outside of the core tube, respectively, to restrain the global and local buckling of the core tube. Based on the yield criteria of fringe fiber, a design method for restraining tubes is proposed. The applicability of the proposed design equations are verified by TTBRBs with different radius-thickness ratios, with different gap widths between core tube and restraining tubs, and with different levels of ${\sigma}_{{\theta},pre}$. The outer and inner tubes will restrain the deformation of the core tube in radius direction, which causes circumference stress (${\sigma}_{\theta}$) in the core tube. Together with the ${\sigma}_{{\theta},pre}$ in the core tube that is applied through interference fit of the three tubes, the yield strength of the core tube in the axial direction is improved from 160 MPa to 235 MPa. Effects of gap width between the core tube and restraining tubes, and ${\sigma}_{{\theta},pre}$ on hysteretic behavior of TTBRBs are presented. Analysis results showed that the gap width and the ${\sigma}_{{\theta},pre}$ can significantly affect the hysteretic behavior of a TTBRB.

• BMB Reports
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• v.30 no.4
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• pp.269-273
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• 1997

Heptocvte-specific expression induced by Hepatitis B virus (HBV) enhancer 2-core gene promoter was examined in various hepatocyte and non-hepatocyte cell lines. using non-viral and retroviral vector systems in which chloramphenicol acetyltransferase (CAT) is used as a reporter. The non-viral plasmid containing the HBV enhancer 2-core promoter exhibited 22 and 66% of CAT activities in hepatoma cell lines. HepG2 and Hep3B, respectively when compared with CAT activity expressed by CMV promoter. The CAT activities, however. were found to be marginal in other tested hepatoma cell lines as well as mouse primary hepatocytes and non-hepatocytes. The HBV enhancer 2 located upstream the CMV promoter did not affect the CMV promoter activity nor provided hepatocyte-specific expression. Transfection of retroviral plasmid DNA containing the HBV enhancer 2-core promoter as an internal promoter exhibited high and specific CAT expression in HepG2 and Hep3B cell lines but the activity value was 5 to 10 fold lower than the non-viral plasmid with identical promoter. These results suggest that the usage of HBV enhancer 2-core promoter for liver specific expression is limited to certain vectors and hepatocyte cell lines.

• Management & Information Systems Review
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• v.19
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• pp.145-170
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• 2006

The purpose of this study is to examine the relationship between core factor of Knowledge Management(KM) and organizational effectiveness. The objects of study are middle manager in hosing construction and civil engineering and construction industry, and the sample size is 228. The core factor of KM and indicator of organizational effectiveness are drawn by literature survey. The core factors are classified into human capital, organizational capital, structural capital, (to put it concretely), job capability, human relation, strategy, information technology, process, sharing culture, leadership, measurement. The indicator of organizational effectiveness are measured by job satisfaction, organization loyalty, competitiveness. The main results of this study can be summarized as the following. 1) The core factor of KM has a positive relationship to organizational effectiveness. Especially, the core factor of sharing culture and leadership are strongly relationship with organizational effectiveness. 2) There was a high positive correlation between job satisfaction and organization loyalty. 3) Human, structural, and structural capital had a different affect on organizational effectiveness. 4) The more job position and educational level high, the more they recognized that KM is necessary for their organization. 5) Among the success factor in KM, the factor of job capability was well perceived to respondent. According to this study, we can analyzed the relationship between success factor and organizational effectiveness, and drawn the most influence success factor on organizational effectiveness. Concurrently, the results of this study will be useful guidelines for shaping the KM operation framework in construction industry.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.68.4-69
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• 2016

We report preliminary results of KaVA observations of central galaxies in cool-core and non cool-core clusters. The main goal is to study how cooling environments of galaxy clusters affect the central AGN activities especially at its innermost region. For KaVA observations, 7 radio bright AGNs have been selected from the extended Highest Flux Galaxy Cluster Sample (eHIFLUGCS; the X-ray flux limited & all sky galaxy cluster catalog) with various cooling timescales. In our previous KVN study, we have found that most AGNs in the cool-core clusters show the hint of pc-scale jet-like features while the ones in the non cool-core clusters do not. Using the KaVA 22/43 GHz data of a much higher resolution than the KVN resolution, we have investigated detailed pc-scale jet properties such as physical size, morphology, and radiative age. Based on the KaVA data, we discuss the effect of cluster cooling environment on the evolution of AGNs in the cluster center.

• East Asian Economic Review
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• v.26 no.3
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• pp.205-225
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• 2022

Different types of corporate ownership may affect the environment among firms and could influence the decisions of new entities in the region. This study determines the role of state-owned enterprises (SOEs) in hindering new foreign manufacturing firms in the Yangtze River delta (YRD). The negative binomial regression is used for city-sector level data and the following points summarize the results: Firstly, the unique privileges that SOEs enjoy alongside governmental support create difficulties for foreign firms trying to establish themselves near existing SOEs. Secondly, although core cities are more attractive to foreign firms than peripheral cities, the role of core-periphery reveals that, in spite of all the regional advantages core cities could offer, whenever the share of SOEs is higher, the core-periphery system will have an adverse impact on new foreign firms. In other words, government preference for SOEs can suppress the attraction of foreign start-ups. However, after 2008, the governmental authorities finally succeeded in implementing their promising policy of fair treatment and competition in only the core cities.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1A
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• pp.90-95
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• 2000

In the Ordered Core Based Tree(OCBT) protocol, a core location is the most important feature to affect the performance. In this paper, the location placement of multiple level cores is studied. The proposed algorithm isthat each node in the network evaluates a sum of shortest path costs from all the other nodes and the entirenetwork is divided into a hierarchy region to have 3-logical level(Small, Medium, Large). The node to have thelowest cost in each S-Region is decided to be a core node. Then, the core nodes in the each S-Region evaluatea sum of shortest path costs from all the other core nodes in the same M-Region. The core node to have thelowest cost is decided to be the upper level core node. Similarly the highest level core node is decided in theL-Region. The proposed algoritthm is compared with conventional two methods to put the core nodes in thenetwork One is the random method to put the core nodes randomly. The other is the center method to locatethe core node at the nearest node from the center of each S-Region and then to locate the highest level corenode at the nearest core node from the center of the entire network. Extensive simulations are performed in theview of mean tree cost and join latency. Simulation results show that the proposed algorithm has betterperformance than random method or center method.