• The KIPS Transactions:PartA
• /
• v.12A no.5 s.95
• /
• pp.433-440
• /
• 2005

The sharing of objects for authoring frequently occurs among participating users in a cooperative authoring system where many users can collaborate. Floor control is therefore needed not only for minimizing the race condition during object accesses but also for ensuring the exclusive use of objects. h floor is a temporary access right that is given to a participating user who wants to use a shared object. Although the floor control methods for a single session environment can be found in various literature, those methods for a multi-session environment can hardly be found. In a multi-session environment, an object can be shared by multiple sessions. As a solution to the problems due to object sharing in such an environment, this paper presents a floor control method based on the chair-of-chair guidance. This method is an extension of those based on traditional chair guidance; the chair-of-chair elected among session chairs exists in this method.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.3
• /
• pp.1263-1279
• /
• 2020

Activating appropriate roles for a session in the role-based access control (RBAC) model has become challenging because of the so-called role explosion. In this paper, factors and issues related to user-driven role management are analysed, and a session role activation (SRA) problem based on reasonable assumptions is proposed to describe the problem of such role management. To solve the SRA problem, we propose an extended RBAC model with context-based role filtering. When a session is created, context conditions are used to filter roles that do not need to be activated for the session. This significantly reduces the candidate roles that need to be reviewed by the user, and aids the user in rapidly activating the appropriate roles. Simulations are carried out, and the results show that the extended RBAC model is effective in filtering the roles that are unnecessary for a session by using predefined context conditions. The extended RBAC model is also implemented in the Apache Shiro framework, and the modifications to Shiro are described in detail.

• Korean Journal of Human Ecology
• /
• v.14 no.1
• /
• pp.59-68
• /
• 2005

The purposes of this study were to investigate the relationship between children's private speech during the individual session and maternal scaffolding during mother-child session. Subjects were twenty 3-year-old children and twenty 5-year-old children and their mothers recruited from day-care centers in Seoul. Mother-child interaction was videotaped for 15 minutes and maternal utterances were transcribed for analysis maternal scaffolding. Individual session of child after 3-5days was videotaped for 15 minutes and children's utterance was transcribed. Subcategories of maternal scaffolding were significantly related with children's private speech during individual session. There did appear to be an age difference in this relationship. In verbal strategy for scaffolding that 3-year-old's mother used, other-regulation and control, praise strategy was significantly related with children's private speech. In verbal strategy for scaffolding that 5-year-old's mother used, other-regulation and control, teaching strategy was significantly related with children's private speech. In maternal physical control strategy, withdrawal of mother physical control the maze task over time was significantly related with children's private speech. Withdrawal of mother physical control 5-year-old's physical performance was significantly related with children's private speech.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.12 no.1
• /
• pp.35-41
• /
• 2016

Internet of Things (IoT) services are widely used in appliances of daily life and industries. IoT services also provide various conveniences to users and are expected to affect value added of all industries and national competitiveness. However, a variety of security threats are increased in IoT environments and lowers reliability of IoT devices and services that make some obstacles for commercialization. The attacks arising in IoT environments are making industrial and normal life accidents unlike existing information leak and monetary damages, and can expand damage scale of leakage of personal information and privacy more than existing them. To solve these problems, we design a session key based access control scheme for secure communications in IoT environments. The proposed scheme reinforces message security by generating session key between device and access control network system. We analyzed the stability of the proposed access scheme in terms of data forgery and corruption, unauthorized access, information disclosure, privacy violations, and denial of service attacks. And we also evaluated the proposed scheme in terms of permission settings, privacy indemnity, data confidentiality and integrity, authentication, and access control.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.45 no.5
• /
• pp.117-124
• /
• 2008

In this paper, the call setup performance of the CSCF(Call Session Control function) that manages the session control in providing the IMS(IP Multimedia subsystem)-based multimedia service in the BcN(Broadband convergence Network) is analyzed. While the performance related with the call/session of the SIP-Based voice service is analysed, the study for the call recessing performance of the IMS-based multimedia service is insufficient. In this paper, as, the processing capacity and subscriber number of CSCF were changed, the call setup delay time according to the session setup procedure of IMS was measured using the M/M/1 queuing model and OPNET simulation. The experimental results show that the sudden increased delay showed up in case the session establishment requirement ratio of total users over 13% of the CSCF processing capacity. Therefore, the user number and capacity of CSCF suitable for the session establishment delay threshold can be calculated or estimated.

• Journal of KIISE:Computing Practices and Letters
• /
• v.11 no.4
• /
• pp.312-333
• /
• 2005

SIP(Session Initiation Protocol) has been proposed for session control protocol of Internet multimedia communication system like VoIP(Voice over IP). SIP has complicated session control steps to support various kinds of audio and video formats and to assure service quality of real time data communication. Up until now, existing protocol analyzers can not provide such detailed information of SIP based communication system. In this paper, therefore, we propose a new protocol analyzer as a tool that can analyze and diagnose SIP based multimedia communication system throughout the session initiation, data exchange and session change steps. The propose traffic analyzer, which is called STAT(SIP based Traffic Analysis Tool), Is implemented on Winder's environment so that it is generally usable and extensible. Since STAT analyze low level packets captured via Ethernet broadcasting property, it is able to provide session status and real time traffic monitoring information without any affection to the communication system. The STAT which is implemented in this paper. therefore, is expected to be a useful tool for developing and managing of a SIP based multimedia communication system.

• The KIPS Transactions:PartC
• /
• v.16C no.3
• /
• pp.383-392
• /
• 2009

Next generation network (NGN) is a packet-based converged network to support session and non-session services in QoS-enabled broadband transport network. QoS based resource control must be defined to support differentiated services for various network users in NGN. This paper defined parallel control schemes for NGN resource control interfaces to minimize session and resource control delays. We simulated the existing and proposed NGN control schemes to measure and analyze control delays and completion ratios. By arrival rate of 120 in two-phase resource control, we checked out that completion ratios of sequential and parallel schemes achieved 100%, and the control delay of parallel scheme was improved by about 21.5% compared to that of sequential scheme.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.17
• /
• pp.7287-7290
• /
• 2014

Background: Brief physician counselling has been shown to be effective in improving smokers' behaviour. If the counselling sessions can be given at the workplace, this would benefit a larger number of smokers. This study aimed to determine the effectiveness of a ten-minute physician counseling session at the workplace in improving smoking behaviour. Materials and Methods: This prospective randomised control trial was conducted on smokers in a factory. A total of 163 participants were recruited and randomised into control and intervention groups using a table of random numbers. The intervention group received a ten-minute brief physician counselling session to quit smoking. Stages of smoking behaviour were measured in both groups using a translated and validated questionnaire at baseline, one month and three months post intervention. Results: There was a significant improvement in smoking behaviour at one-month post intervention (p=0.024, intention to treat analysis; OR=2.525; CI=1.109-5.747). This was not significant at three-month post intervention (p=0.946, intention to treat analysis; OR=1.026; 95% CI=0.486-2.168). Conclusions: A session of brief physician counselling was effective in improving smokers' behaviour at workplace, but the effect was not sustained.

• Journal of Korean Academy of Nursing
• /
• v.42 no.4
• /
• pp.599-607
• /
• 2012

Purpose: This study was conducted to evaluate the effect of a one-session spouse-support enhancement childbirth education on childbirth selfcefficacy and perception of childbirth experience. Methods: The design of this study was a nonequivalent control group pretest-posttest experiment. The participants in the study were 31 couples in the experimental group and 30 in the control group. The experimental couples were provided with one session on spouse-support enhancement childbirth education the night before delivery. Data were collected at two hours after delivery using the Childbirth Self-Efficacy Inventory (CBSEI) and perception of childbirth experience scale. Data were analyzed using PASW statistics 18 program. Frequencies, percentage, mean, $x^2test$, t-test were used for data analysis. Results: Childbirth self-efficacy significantly increased in the experimental group as compared to the control group, but there was no significant difference in perception of childbirth experience in the experimental group compared to the control group. Conclusion: The results suggest that a one-session childbirth education has beneficial effects on enhancing childbirth self-efficacy in pregnant couples. A one-session spouse-support enhancement childbirth education is recommended as an effective nursing intervention to promote couple's childbirth self-efficacy and it is also recommended that modifications of program to promote women's childbirth experience should be considered.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.12
• /
• pp.109-117
• /
• 2020

In this paper, we analyze LADN(Local Area Data Network) that provides high throughput, low latency and service localization for 5G wireless networks and propose an enhanced control protocol design for LADN in 5G wireless networks. The concept of LADN is newly introduced in 3GPP 5G communication system and the LADN is a data network to which the UE(User Equipment) can connect with a specific LADN session only when the UE is located in a certain service area. If the LADN information between the UE and core network is not identical, the LADN session cannot be properly established. The proposed approach promplty synchronizes the LADN information between the UE and core network by using the specific registration procedure and appropriately establishes the LADN session, when the establishment of the LADN session is failed. Consequently, the proposed enhanced control protocol design(ECP) can prevent unnecessary signalling overhead and communication delay for LADN in 5G wireless networks.