• KIEAE Journal
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• v.9 no.5
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• pp.21-28
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• 2009

In apartment buildings, casualties, especially fatalities have occurred in balcony areas in fires if residents fail to escape to the main entrance. Potential consequences of a particular infrequent event should be considered. In attempting to design apartment buildings for fire safety, alternative escape methods such as vertical penetration could be considered. The purpose of this study is to investigate present building regulations regarding apartment buildings and examine pros and cons of the current escape method and alternative escape methods. Focus group interview was conducted to discuss problems of fire escape methods. In addition, questionnaires were distributed to field professionals working in architecture, construction and related industries. Among 500 questionnaires distributed, 192 questionnaires were collected. Usable 162 questionnaires were analyzed using SPSS 15. Regarding alternative fire escape methods, several concerns were mentioned. Safety, privacy, security, effectiveness of escape, water proof problems were raised. Based on the opinions, vertical penetration between apartment unit appeared more safe, secure, effective than horizontal penetration. However, both methods have its own pros and cons under specific contexts. Alternative escape methods need be considered for a selective options for residents in case of fire.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.9
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• pp.2385-2401
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• 1996

In this paper, a management model and a path trace algorithm are proposed for the end-to-end path tracing management in ATM network. Proposedmodel is based on the TINA(Telecommunication Information Networking Architecture) and computational object(CO) of ODP(Open Distributed Processing).We related computational object for the path trace to another computational object which covers the ATM routing and established operational procedure according to this relationship. This procedure identifies the end-to-end by way of tracing the ATM connections then collect identification information on the that path. End-to-end trace is performed on the network management level. Broadcasting-with-synchronized-control and GTM(Global Ticket Method) are proposed as path trace algorithm considering the real time properties and data ingetrity. Computer simulations are also performed to evaluate the performance of the proposed algorithm and its resuls are shown in this paper.

• Journal of the Korea Society of Computer and Information
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• v.15 no.5
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• pp.93-101
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• 2010

Although various network management architectures such as centralized, distributed, and hybrid have been presented, any one is not always efficient in all the environment. In this paper, we propose a hierarchical and split network management architecture based on MA+SNMP in order to manage a network of many small NEs distributed over the wide area. Our hierarchical architecture has MA-based proxy management nodes for the flexibility and overhead reduction in NMS as well as SNMP-based NEs considering NE's capacity. Through the analysis with real experiments, we show that our proposal improves some drawbacks and the processing delay of the existing architectures in the given environment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.2
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• pp.31-48
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• 2019

The purpose of this study is to present the basic data for establishing the plan of usage and management of healing forest by surveying and analysing the vascular plants distributed in Jangseong Healing Forest. The numbers of vascular plants were summarized as 338 taxa including 85 families, 211 genera, 294 species, 3 subspecies, 33 varieties and 8 forms. In the result of life form, hemicryptophytes and geophytes were the most common and hydrophytes were the least. The rare plants were 5 taxa including Abies koreana Wilson(planted), Thuja orientalis L.(planted), Scutellaria insignis Nakai, Tricyrtis macropoda Miq. and Arisaema heterophyllum Blume. The Korean endemic plants were 12 taxa including Philadelphus schrenkii Rupr., Indigofera koreana Ohwi, Lycoris flavescens M.Y.Kim ＆ S.T.Lee and so forth. The specific plants by floristic region were 28 taxa including 2 taxa of grade IV, 3 taxa of grade III, 7 taxa of grade II and 16 taxa of grade I. The naturalized plants were 20 taxa including Fallopia convolvulus (L.) $A.L{\ddot{o}}ve$, Ailanthus altissima (Mill.) Swingle, Veronica arvensis L., Poa pratensis L. and so forth. The invasive alien plants were Rumex acetocella L. and Ambrosia artemisiifolia L..

• International Journal of Computer Science & Network Security
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• v.21 no.7
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• pp.331-340
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• 2021

The Internet of Things (IoT) is a rapidly growing physical network that depends on objects, vehicles, sensors, and smart devices. IoT has recently become an important research topic as it autonomously acquires, integrates, communicates, and shares data directly across each other. The centralized architecture of IoT makes it complex to concurrently access control them and presents a new set of technological limitations when trying to manage them globally. This paper proposes a new decentralized access control architecture to manage IoT devices using blockchain, that proposes a solution to concurrency management problems and enhances resource locking to reduce the transaction conflict and avoids deadlock problems. In addition, the proposed algorithm improves performance using a fully distributed access control system for IoT based on blockchain technology. Finally, a performance comparison is provided between the proposed solution and the existing access management solutions in IoT. Deadlock detection is evaluated with the latency of requesting in order to examine various configurations of our solution for increasing scalability. The main goal of the proposed solution is concurrency problem avoidance in decentralized access control management for IoT devices.

• ETRI Journal
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• v.44 no.6
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• pp.1020-1033
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• 2022

In this paper, we propose novel disaggregated memory module (dMM) architecture and memory access control schemes to solve the collision and contention problems of memory disaggregation, reducing the average memory access time to less than 1 ㎲. In the schemes, the distributed scheduler in each dMM determines the order of memory read/write access based on delay-sensitive priority requests in the disaggregated memory access frame (dMAF). We used the memory-intensive first (MIF) algorithm and priority-based MIF (p-MIF) algorithm that prioritize delay-sensitive and/or memory-intensive (MI) traffic over CPU-intensive (CI) traffic. We evaluated the performance of the proposed schemes through simulation using OPNET and hardware implementation. Our results showed that when the offered load was below 0.7 and the payload of dMAF was 256 bytes, the average round trip time (RTT) was the lowest, ~0.676 ㎲. The dMM scheduling algorithms, MIF and p-MIF, achieved delay less than 1 ㎲ for all MI traffic with less than 10% of transmission overhead.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.3975-3984
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• 2022

Distributed control system architecture is adopted for I&C systems of Prototype Fast Breeder Reactor, where the geographically distributed control systems are connected to centralized servers & display stations via switched Ethernet networks. TCP/IP communication plays a significant role in the successful operations of this architecture. The communication tasks at control nodes are taken care by TCP/IP offload modules; local area switched network is realized using layer-2/3 switches, which are finally connected to network interfaces of centralized servers & display stations. Safety, security, reliability, and fault tolerance of control systems used for safety-related applications of nuclear power plants is ensured by indigenous design and qualification as per guidelines laid down by regulatory authorities. In the case of commercially available components, appropriate suitability analysis is required for getting the operation clearances from regulatory authorities. This paper details the proposed approach for the suitability analysis of TCP/IP communication nodes, including control systems at the field, network switches, and servers/display stations. Development of test platform using commercially available tools and diagnostics software engineered for control nodes/display stations are described. Each TCP link behavior with impaired packets and multiple traffic loads is described, followed by benchmarking of the network switch's routing characteristics and security features.

• IE interfaces
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• v.17 no.1
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• pp.128-141
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• 2004

Although a number of container terminal simulators have been developed for various purposes, none of the existing simulators allow the system structure to reuse the system structure depending on application. Our goal is to develop highly reusable, highly inter-operable and flexible container terminal simulation system. The High Level Architecture(HLA) is an architecture for reuse and inter-operation of simulation. It is based on premise that no simulation can satisfy all use and users. An individual simulation or set of simulations developed for one purpose can be applied to another application under the HLA concept of the federation : a composable set of interacting simulations. The intent of the HLA is a structure which will support reuse of capabilities available in different simulations, ultimately reducing the cost and time required to create a synthetic environment for a new purpose, and the possibility of distributed collaborative development of complex simulation applications. In this paper, we discuss the design of a HLA-based port container terminal simulation system. Furthermore, we describe various technical motivations for HLA, the key elements of the architecture and how they are minimum and essential to the goal of reuse and interoperability.

• Journal of Computing Science and Engineering
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• v.9 no.4
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• pp.163-176
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• 2015

Self-organization of distributed wireless sensor nodes is a critical issue in wireless sensor networks (WSNs), since each sensor node has limited energy, bandwidth, and scalability. These issues prevent sensor nodes from actively collaborating with the other types of sensor nodes deployed in a typical heterogeneous and somewhat hostile environment. The automated self-organization of a WSN becomes more challenging as the number of sensor nodes increases in the network. In this paper, we propose a dynamic self-organized architecture that combines tree topology with a drawn-grid algorithm to automate the self-organization process for WSNs. In order to make our proposed architecture scalable, we assume that all participating active sensor nodes are unaware of their primary locations. In particular, this paper presents two algorithms called active-tree and drawn-grid. The proposed active-tree algorithm uses a tree topology to assign node IDs and define different roles to each participating sensor node. On the other hand, the drawn-grid algorithm divides the sensor nodes into cells with respect to the radio coverage area and the specific roles assigned by the active-tree algorithm. Thus, both proposed algorithms collaborate with each other to automate the self-organizing process for WSNs. The numerical and simulation results demonstrate that the proposed dynamic architecture performs much better than a static architecture in terms of the self-organization of wireless sensor nodes and energy consumption.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.2
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• pp.182-194
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• 1995

The major objective of this study was to develop recommendations for improving the design of pergola facilities located in neighborhood parks. The study employed the following methods : Physical measures and questionnaires. Physical treasures were taken of certain environmental attributes such as pergola sizes, structures, materials, etc. Questionnaires were randomly distributed to pergola users on the same day on which physical measures were scheduled. All data were collected in 1994 during the season of pergola use, September 3 to October 9. The major findings are as follows; 1. Of the 508 respondents to the question about use motivations, approximately 32% were a shady place, 18% seating arrangements suitable for conversation, 15% unconsciously, 13% a lack of bench in the park, 9% good view, and 13% other. 2. Regression analysis indicated that the best predictors of pergola user' satisfaction were : harmony with surroundings, accessibility, aesthetics of pergolas and benches, function of benches, and climbing plants. 3. Pergola design needs to be developed because pergola users were less satisfied with their pergola than with the park.