• The KIPS Transactions:PartC
• /
• v.9C no.1
• /
• pp.79-88
• /
• 2002

Transcoding proxy strategy has been widely used as a means to reduce the delay in retrieving Web pages over wireless mobile data service networks. However, this strategy has the serious drawbacks of being a potential point of failure or a bottleneck of the service. We developed a distributed proxy server system in which multiple proxy servers are installed at geographically dispersed locations and share the workloads among them by serving mobile hosts only within assigned regions. A new handoff message protocol to enable handoffs between proxies as the mobile hosts move between regions is proposed. According to the proxy server handoff protocol, a client agent at the mobile horst requests a proxy server to start handoff processing by which two proxy servers synchronize distilled data belonging to a HTTP session that must be maintained across the handoff. Also, we introduce the architecture of the proxy server and the client agent that handles the proxy server handoff. Finally, we evaluate the proposed system through performance test.

• The KIPS Transactions:PartC
• /
• v.12C no.2 s.98
• /
• pp.157-168
• /
• 2005

Group key agreement protocols are designed to provide a group of parties securely communicating over a public network with a session key. The mobile computing architecture is asymmetric in the sense of computational capabilities of participants. That is, the protocol participants consist of the stationary server(application servers) with sufficient computational Power and a cluster of mobile devices(clients) with limited computational resources. It is desirable to minimize the amount of computation performed by each group member in a group involving low-power mobile devices such as smart cards or personal digital assistants(PDAs). Furthermore we are required to update the group key with low computational costs when the members need to be excluded from the group or multiple new members need to be brought into an existing group. In this paper, we propose a dynamic group key protocol which offers computational efficiency to the clients with low-power mobile devices. We compare the total communicative and computational costs of our protocol with others and prove its suity against a passive adversary in the random oracle model.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.23 no.9
• /
• pp.1160-1172
• /
• 2019

Federated authentication is a user authentication and authorization infrastructure that spans multiple security domains. Many overseas Web applications have been adopting SAML-based federated authentication. However, in Korea, it is difficult to apply the authentication because of the high market share of a specific Web (application) server, which is hard to use open-source SAML software and the high adoption of Java-based standard framework which is not easy to integrate with SAML library. This paper proposes the SAML4J, which is developed in order to have Web applications easily and safely integrated with the Java-based framework. SAML4J has a developer-friendly advantage of using a session storage independent of the framework and processing Web SSO flows through simple API. We evaluate the functionality, performance, and security of the SAML4J to demonstrate the high feasibility of it.

• The Journal of Korean Society for School & Community Health Education
• /
• v.22 no.1
• /
• pp.37-53
• /
• 2021

Background and objectives: Human papillomavirus (HPV) is the most common sexually transmitted infection globally and is responsible for multiple clinical outcomes, including genital warts and cervical, anal, and oropharyngeal cancers. Despite the well established burden of HPV on both men and women, vaccine uptake among men is critically low in Korea. A preliminary step to combat this issue is to target parents of male adolescents. In the present study, we aimed to assess any change observed in parents' HPV knowledge and attitudes towards male HPV and subsequent willingness to vaccinate their sons following an HPV educational intervention. Methods: On November 14, 2020, a one-time HPV educational session was conducted and parents (n=136) completed self-administered pre-/post-test questionnaires that included previously validated survey items. Paired t-tests were used to evaluate change in HPV-related knowledge, attitudes and intent for HPV vaccination. Results: Following the intervention, participants reported increased scores in HPV and vaccine related knowledge by approximately 4 and 1.5 points, respectively (p<.001). Parents scored higher on perceived benefits of the vaccine, perceived social influence on vaccination decision and perceived severity of diseases caused by HPV infections, whereas lower scores were observed for perceived harm of the vaccine, and difficulties communicating with their sons about sex and HPV vaccination. Following the intervention, those without the intent to vaccinate their sons significantly decreased and those who intended to vaccinate their sons though not in the next six months significantly increased (χ2=33.045, p<.001) Conclusion: Our educational intervention resulted in an increase in HPV-related knowledge with a positive impact on parents' attitudes toward male HPV vaccination. We expect that this study can serve as a pivotal reference to promote the unexplored issue of HPV vaccination among male adolescents in Korea.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.31 no.6
• /
• pp.1247-1260
• /
• 2021

For more efficient energy management of nodes in wireless sensor networks, research has been conducted on mobile sink nodes that deliver data from sensor nodes to server recently. UAV (Unmanned Aerial vehicle) is used as a representative mobile sink node. Also, most studies on UAV propose algorithms for calculating optimal paths and have produced rapid advances in the IoD (Internet of Drones) environment. At the same time, some papers proposed mutual authentication and secure key exchange considering nature of the IoD, which requires efficient creation of multiple nodes and session keys in security perspective. However, most papers that proposed secure communication in mobile sink nodes did not protect end-to-end data privacy. Therefore, in this paper, we propose integrated security model that authentication between mobile sink nodes and sensor nodes to securely relay sensor data to base stations. Also, we show informal security analysis that our scheme is secure from various known attacks. Finally, we compare communication overhead with other key exchange schemes previously proposed.

• Medical Lasers
• /
• v.8 no.1
• /
• pp.24-27
• /
• 2019

Seborrheic keratoses (SKs) have been treated with non-ablative longpulsed (LP) lasers, including LP 532-nm neodymium (Nd): yttrium aluminum garnet (YAG), LP 695-nm ruby, LP 755-nm alexandrite (Alex), and LP 1,064-nm Nd:YAG lasers, with a pulse durations of 1-300 msec. Dual-wavelength LP 755-nm Alex/1,064-nm Nd:YAG laser systems have been used to remove hair follicles and treat various vascular and pigmented disorders by sequentially delivering two pulses of different wavelengths with interpulse intervals in the millisecond range. This paper reports the case of a female patient with multiple, discrete, light brown SKs on the dorsum of both hands that were treated effectively with one session of dual-wavelength LP 1,064-nm Nd:YAG/755-nm Alex laser treatment. The treatment settings for the LP Nd:YAG laser were comprised of a wavelength of 1,064 nm, fluence of 50 J/cm², pulse duration of 5 msec, and beam size of 3 mm. The settings for the LP Alex laser were comprised of a wavelength of 755 nm, fluence of 50 J/cm², pulse duration of 5 msec, and beam size of 3 mm. A hybrid mode was used to automatically deliver LP Nd:YAG and LP Alex laser pulses in succession at interpulse intervals of 20 msec. Six weeks after treatment, the patient exhibited remarkable improvement of the light brown seborrheic keratoses and was satisfied with the results.

• The Journal of Korean Academy of Sensory Integration
• /
• v.21 no.2
• /
• pp.1-11
• /
• 2023

Objective : The purpose of this study was to investigate the effects of computerized cognitive rehabilitation on the attention of children with autism spectrum disorder (ASD). Methods : A multiple-baseline design was used in combination with a single-subject experimental research design. A total of 15 sessions were conducted three times a week, each lasting for 30 minutes. The maintenance and selective attention tests in the attention area of the computerized cognitive rehabilitation program were evaluated in random order after each session was completed. To evaluate the participants' selective attention, star cancellation tests was performed as pre- and post-tests. Results : After the computerized cognitive rehabilitation intervention, the accuracy of the participants' attention improved in terms of the maintenance and selective attention tests. In the analysis involving the two standard deviation bands, participants 1 and 2 showed a significant improvement, whereas participant 3 did not show a significant improvement, although the average value improved. Conclusion : The results of this study confirmed that cognitive rehabilitation involving a computerized cognitive rehabilitation program had a positive effect on the attention of three children with ASD.

• International Journal of Computer Science & Network Security
• /
• v.24 no.3
• /
• pp.23-28
• /
• 2024

The multi-tenancy and high scalability of the cloud have inspired businesses and organizations across various sectors to adopt and deploy cloud computing. Cloud computing provides cost-effective, reliable, and convenient access to pooled resources, including storage, servers, and networking. Cloud service models, SaaS, PaaS, and IaaS, enable organizations, developers, and end users to access resources, develop and deploy applications, and provide access to pooled computing infrastructure. Despite the benefits, cloud service models are vulnerable to multiple security and privacy attacks and threats. The SaaS layer is on top of the PaaS, and the IaaS is the bottom layer of the model. The software is hosted by a platform offered as a service through an infrastructure provided by a cloud computing provider. The Hypertext Transfer Protocol (HTTP) delivers cloud-based apps through a web browser. The stateless nature of HTTP facilitates session hijacking and related attacks. The Open Web Applications Security Project identifies web apps' most critical security risks as SQL injections, cross-site scripting, sensitive data leakage, lack of functional access control, and broken authentication. The systematic literature review reveals that data security, application-level security, and authentication are the primary security threats in the SaaS model. The recommended solutions to enhance security in SaaS include Elliptic-curve cryptography and Identity-based encryption. Integration and security challenges in PaaS and IaaS can be effectively addressed using well-defined APIs, implementing Service Level Agreements (SLAs), and standard syntax for cloud provisioning.

• Journal of Music and Human Behavior
• /
• v.3 no.2
• /
• pp.29-44
• /
• 2006

Trust and understanding relationship promoted between a therapist and a client is the basic building block to successful recovery. Its importance is not only pertaining to the music therapy but also to counseling and psychological therapy. Because of its gnificance, broad spectrum of research has been conducted for quite a long time. Historically, researches have been focused on therapists or client's chological variables rather than emotional effects on each other that occur during the therapy session. Recently researchers turned their attention to emotional relationship between a therapist and a client. With recent advances in the field of music and psychological therapy, subsequent study has been conducted to investigate the role that music plays in the therapeutic relationship. For this research, eleven music therapy sessions were conducted for the adult females who are alcoholics. The first three sessions were of group therapy. Fourth to eleventh therapy session was done individually. Throughout the research case-by-case study has been conducted on the basis of the analysis of video and audio taped materials. Analysis depends heavily on its reference from the Amir's music research of 1990, which used Ferrara's seven phases of phenomenological study. Especially, verbal and nonverbal communications were closely analyzed in musical perspective. Research revealed that music and musical instruments act as a mediator between a therapist and a client. By doing so, it protects a therapist from unnecessary negative emotional displacements of a client and creates mutual reliability between a therapist and a client. Here, research suggests that music and musical instrument play a central role in building relationship between a therapist and a client, and it indicates that it has positive effect on treatment.

• Journal of KIISE:Information Networking
• /
• v.35 no.5
• /
• pp.409-414
• /
• 2008

In mobile ad hoc networks, most of on demand routing protocols such as DSR and AODV do not deal with traffic load during the route discovery procedure. To solve the congestion and achieve load balancing, many protocols have been proposed. However, the existing load balancing schemes has only considered avoiding the congested route in the route discovery procedure or finding an alternative route path during a communication session. To mitigate this problem, we have proposed a new scheme which considers the packet bursting mechanism in congested nodes. The proposed packet bursting scheme, which is originally introduced in IEEE 802.11e QoS specification, is to transmit multiple packets right after channel acquisition. Thus, congested nodes can forward buffered packets promptly and minimize bottleneck situation. Each node begins to transmit packets in normal mode whenever its congested status is dissolved. We also propose two threshold values to define exact overloaded status adaptively; one is interface queue length and the other is buffer occupancy time. Through an experimental simulation study, we have compared and contrasted our protocol with normal on demand routing protocols and showed that the proposed scheme is more efficient and effective especially when network traffic is heavily loaded.