Introduction to Home Networking and Its Programming Environment as a Pervasive Computing Model

Hong, Gunho,Song, Hayoon Research Institute for Science & Technology HONG-I 2002 Hongik Journal of Science and Technology Vol.6 No.-

The traditional home appliances which were not considered as computing platform become smart devices with the advance of microprocessor technology. And the proliferation of Internet made the home as a major information consuming place. These phenomenon have converged into home networking. Home network can be defined as network of smart devices with access to broadband network. Smart devices with networking capabilities can provide various applications and service model. In this paper, the core characteristics of home network are described as a pervasive computing model. Then the standards and the problems addressed by the standard technologies are examined. By viewing the home network as software development environment, the programming environment of smart device for home network is presented in depth. The evolution of home networking and realization of pervasive computing environment are discussed at the end of this paper.

Synthesis of Several Organometallic Compounds as Electroluminescent Materials

Ha,Yun-kyoung Research Institute for Science & Technology HONG-I 1998 Hongik Journal of Science and Technology Vol.2 No.-

To develop practical electroluminescent devices, a lot of efforts such as finding a good candidate for emitter materials, employing a variety of hole transporting layers, and incorporating electron transporting materials to the devices have been made by many researchers. As one of there efforts, synthesis of eight organometallic complexes for the use as emitter materials in electroluminescent devices was performed here in. The compounds synthesized in this study include Be(bq)₂, Zn(bq)₂, Be(mq)₂, Zn(mq)₂, Be(box)₂, Zn(box)₂, Tb(MeOBB)₃, and Eu(MeOBB)₃[where bq = the anion of 10-hydroxybenzo[h]quinoline; mq = the anion of 8-hydroxyquinaldine; box = the anion of 20)20hydroxyphenyl)benzoxazole; MeOBB = 4-methoxy benzoylbenzoate] As a ligand for the lanthanide ions(Tb and Eu), MeOBB was also synthesized in this study. The luminescence colors of solid compounds listed above were reviewed through the 365nm light irradiation. These compounds will be applied to electroluminescence devices as emitter materials and/or electron transporting layers, and their applicability for the efficient electroluminescent devices will be shortly evaluated.

High-Speed IP Routing Lookups with Fast Updates

Kim, Byung-Yeob,Kim, Kyung-Duk,Choi, Yoon-Hwa Research Institute for Science & Technology, Hong- 2001 Hongik Journal of Science and Technology Vol.5 No.-

Most of the existing IP address lookup schemes emphasize the table lookups with little attention to table updates. Updating the routing table often requires a considerable time overhead, especially for gigabit backbone routers. This paper presents a high-speed lookup scheme with a small bounded update time for IP forwarding engines in IP routers. It performs one IP address lookup per memory access by employing memory access pipelining and updates the table in the time bounded by the IP packet interarrival time on a gigabit link, regardless of the size of the database. The resulting design requires manageably small memories to be implemented using current SRAM technology.

Representative Strain Value Based Adaptive Mesh Generation for Plane Stress Problems

Jeong, Yochan,Yoon, Chongyul Research Institute for Science & Technology HONG-I 2003 Hongik Journal of Science and Technology Vol.7 No.-

The finite element method is one of the most widely used method of structural analysis that has wide applications in diverse fields of engineering and science. The method has been proven effective and reliable in many practical problems. One of the reasons for the methods' popularity is its ease of use, but still the user has to input a finite element mesh which affects the accuracy of the results. The knowledge required to form an effective mesh for a given problem is somewhat complex and for sometime there has been research effort to automate the generation of the mesh and this is called the adaptive mesh generation scheme. A good adaptive mesh scheme seemed to require an accurate assessment of error and generally this requires some additional computation. This paper looks into the possibility of generating adaptive meshes based on representative strain values in each finite element. The proposed adaptive scheme does not require additional computations other than that used for looking up the data values already computed as finite element analysis results and simple manipulations of these data. Two plane stress problems, a plate with a hole and a deep beam with a concentrated load at the end, are considered to show the progress of the improved generation of adaptive meshes using the scheme.

A Framework for an Implementation of a Software RAID file System on Workstation Clusters

Byun, Seok-Gyu,Noh, Sam H Research Institute for Science & Technology HONG-I 1997 Hongik Journal of Science and Technology Vol.1 No.-

A software RAID file system is defined as a system that distributes data redundantly across an array of disks attached to each of the workstations connected on a high-speed network. This configuration provides higher throughput and availability compared to conventional file systems. In this paper, we present a framework for an implementation of the HiS-RAID(Hong-Ik University Software RAID) file systems for a workstation cluster. To implement such a system, various practical issues must be considered. This paper does this on two specific issues, namely, the distribution of data among the cluster and efficient catching for such an environment. Through simulation studies we investigate various data distribution methods as well as anew catching scheme that may be implementable on HiS-RAID.

Heuristic technology mapping system for complex FPGAs

Lee, Jun-yong Research Institute for Science & Technology HONG-I 1997 Hongik Journal of Science and Technology Vol.1 No.-

이 논문은 복잡한 logic block 구조를 가진 FPGA 를 위한 technology mapper 를 기술한 것이다. 지금까지 개발된 대다수의 technology mappers는 XILINX XC4000 series와 같은 complex logic block architectures 에는 효율적이지 않았다. 제안된 mapper 는 area, timing, routability 등의 특성을 균형 맞추기 위해 constructive mapping algorithm과 fuzzy logic rules을 적용하였다. Mapper 의 성능은 MCNC benchmarks 의 set으로 실험해 보았다.

A New Approach for Providing Security Services to Multicasting in a Large Scale Network

Shim, Young-Chul Research Institute for Science & Technology, Hong- 2000 Hongik Journal of Science and Technology Vol.4 No.-

In this paper an approach for providing security services for multicasting has been presented. We assume the use of IP-SM shared trees and BGMP for an intra-domain routing algorithm and an inter-domain routing algorithm. All the members and senders are authenticated and authorized by an authentication server. Members and senders use capabilities received from the authentication server when they join a multicast group so that illegal hosts or routers may not be able to expand the multicast delivery tree. Messages sent by members are encrypted with a group data key which is shared by all members and changed efficiently whenever a membership changes. Messages sent by a non-member sender are encrypted with a sender-specific key which is shared by that sender and all the members. The authenticity and freshness of a packet is checked by first the edge router of the sending host and all the core routers. Therefore, if a host attempts to inject a bogus packet or replay a packet are thwarted by an edge router. Similar attempts by a corrupt router are thwarted by core routers and the effects of such attempts are contained in a single domain. The proposed security mechanism for multicasting guard against both edge attacks and internal attacks. The approach tries to reduce the overhead on the border routers as much as possible and also provides mechanisms for securely evicting suspicious members or senders.

Design of a Memory Arbiter for Shared Multibuffer ATM Switches

Choi, Yoon-Hwa,Kang, Woon-Cheon,Kim, Byoung-Yeob Research Institute for Science & Technology, Hong- 2000 Hongik Journal of Science and Technology Vol.4 No.-

This paper presents a memory arbiter for shared multibuffer ATM switches. The arbiter plays a pivotal role in providing differentiated services to connections with widely varying requirements. It also has provisions to accommodate multicast traffic. The arbitration process selects a request to be acknowledged based on the service classes and assigned priorities. However, the memory arbiter additionally receives queue status information and takes it into account when there is an overloaded queue. The design employs extremely simple, identical circuits to make it practically useful for high-speed cell switching.

Simulation of Bi-layered PSA Processes

Shin, Heung-Soo Research Institute for Science & Technology, Hong- 2000 Hongik Journal of Science and Technology Vol.4 No.-

Numerical simulation of a 5-bed pressure swing adsorption (PSA) process with bi-layered beds for separation of a multi-component gas mixture was undertaken. An equilibrium model was used with the assumptions of extended Langmuir isotherms for components, isothermal operation, and no pressure drop through a bed. Hydrogen purification from a reformer off-gas using adsorbents of activated carbon and 5A zeolite was considered as a case study. Through intensive simulation study, optimum layering was identified and explained in a view of adsorber dynamics. One finding is that an optimum carbon fraction obtained from breakthrough study did not coincide with that for a PSA process. Thus, care must be taken in deciding optimum layering based only on breakthrough study.

The Development of Software for Adsorptive Oxygen Separation

Choi,Min-Ho Research Institute for Science & Technology HONG- 1999 Hongik Journal of Science and Technology Vol.3 No.-

We developed the software for adsorptive oxygen separation by pressure swing adsorption (PSA) process and investigated the effects of variable valve coefficients on the separation performance. For rapid pressure changing steps such as blow down step and pressurization step, the effect of flow resistance through the valve was considered by valve equation. Linear driving force (LDF) model was used to describe mass transfer between two phases (gas and adsobate solid phase). Coupled Langmuir isotherm was used for each component as a nonlinear adsorption isotherm. In order to consider influence of temperature, energy balance was set up along with mass balance equation. These equations yielded partial differential equations and were solved by numerical method. Several assumptions were made for convenience of simulation. By controlling input data file, separation performance could be obtained for various operating conditions.