• Korean Journal of Oriental Medicine
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• v.8 no.2 s.9
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• pp.37-46
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• 2002

Clinical trials are experimental studies with human subjects in which various limitations and variables exist by their nature. As a preparatory stage for designing clinical trials in Oriental medicine, this study considers a virtual protocol to show guideline regarding tasks necessary when writing a trials protocol. Clinical trials have many difficulties in planning, procedure, and interpretation of results, and these may be influenced by various biases that are difficult to predict and eliminate. To deal with these issues, clinical trials need a collaboration between medical experts and biostatisticians from the beginning, through the entire trial, until the final analysis. Therefore, the first stage of clinical trials is to write out a trial plan among the experts in each field to derive the best design for the trial.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8A
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• pp.1141-1148
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• 1999

In this paper, an RRA_CDMA protocol is proposed for the integrated voice and data services in the cellular packet CDMA systems. The proposed protocol employs the RRA scheme. In the cellular CDMA systems, the backward logical channels are composed of time slots with multiple spreading codes per slot based on WB-TD-CDMA concept. When a voice terminal begins a talkspurt, it reserves one of the available spreading codes in the next slot and uses the reserved channel exclusively untill it ends the talkspurt. On th other hand, whenever a data terminal generates a packet, it selects an avaliable spreading code and transmits its packet. Throughout the results, it is shown that the system capacity increases in proportion to the number of spreading codes.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.6 s.336
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• pp.33-40
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• 2005

In this paper, we analyzed the DRMA(Dynamic Reservation Multiple Access) protocol with Rayleigh fading, shadowing, and capture effect for the Broadband fireless Access System. We consider the TDMA-based protocols, since these are based on the standard for IEEE 802.16 WMAN, IEEE 802.20 MBWA, and ETSI HIPERLAN//2. The results of analytical model will be apply the development of collision resolution algorithm, scheduling algorithm and the dynamic change of system parameters.

• Journal of the Korea Society of Computer and Information
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• v.15 no.11
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• pp.117-124
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• 2010

Appling centralized network management architecture SNMP(Simple Network Management Protocol) to wireless networks causes the network overhead, NAT(Network Address Translation) problem on AP, and performance degradation of mobile nodes. In this paper, we propose an integrated management scheme for wired and wireless networks using mobile agents in order to solve above problems. In our proposed scheme, SNMP is applied to manage wired networks and MAs of SNMP are implemented in APs or wireless nodes to manage wireless networks. In addition, we propose a method to reduce the redundant OID information within SNMP response messages. Through the analysis, we show that our proposal resolves the given problems and reduces the processing delay of the wireless nodes.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.3
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• pp.1052-1070
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• 2016

Wireless Body Area Networks (WBANs) have received a lot of attention as a promising technology for medical and healthcare applications. A WBAN should guarantee energy efficiency, data reliability, and low data latency because it uses tiny sensors that have limited energy and deals with medical data that needs to be timely and correctly transferred. To satisfy this requirement, many multi-radio multi-channel MAC protocols have been proposed, but these cannot be implemented on current off-the-shelf sensor nodes because they do not support multi-radio transceivers. Thus, recently single-radio multi-channel MAC protocols have been proposed; however, these methods are energy inefficient due to data duplication. This paper proposes a TDMA-based single-radio, multi-channel MAC protocol that uses the Unbalanced Star+Mesh topology to satisfy the requirements of WBANs. Our analytical analysis together experiments using real sensor nodes show that the proposed protocol outperforms existing methods in terms of energy efficiency, reliability, and low data latency.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.12
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• pp.1-9
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• 1999

In this paper, the performance of HIPERLAN(HIgh PErformance Radio Local Area Networks) CAC(Channel Access Control) of ETSI(European Telecommunication StandaTds Institute) in Europe, as High speed wireless LAN, is analyzed and estimated by mathematical approaches. The CAC protocol of HIPERLAN is the EY-NPMA(Elimination Yield-Nonpreemptive Priority Multiple Access) which is transmitted after prioritization, elimination and yield phase. We analyzed channel contention phase composed of elimination and yield phase and then throughput is inspected by simulation. This result is useful to design and implement of HIPERLAN protocol.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.3
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• pp.271-276
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• 2016

Cooperative networks enhance the overall communication performance by combining signals from relay nodes and direct signal. In this paper, we analyze the performance of cooperative communication systems which use mixed relaying protocols. By assuming several relay nodes exist between the source node and destination node, we consider the systems use not a single relaying protocol but both decode-and-forward and amplify-and-forward protocols randomly. We analyze the effect of each relying protocol for the overall system performance, and also consider the performance depending on the relay location. Differential modulation scheme which demodulates signal without channel state information is adopted where it can be applicable fast varying channel such as railway environments.

• Advances in Automotive Engineering
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• v.1 no.1
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• pp.61-77
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• 2018

In this study, the effects of sitting position of the driver on the whiplash neck injury have been analyzed experimentally by using hybrid III series 50 percentile male crash test dummy. A testing platform consisting of vehicle ground, driver foot rest, driver seat and a 3-point seatbelt has been prepared. This testing platform and the instrumented crash test dummy are prepared for tests according to the Euro NCAP whiplash testing protocol. The prepared test set-up has been exposed to 3 different acceleration-time loading curves defined in the Euro NCAP whiplash testing protocol by performing sled tests. 9 different sled tests have been performed with the combinations of 3 different seating positions of the crash test dummy and 3 different acceleration-time loading curves. The sensor data obtained from the crash test dummy and high-speed videos taken are analyzed according to the injury assessments criteria defined in the Euro NCAP whiplash testing protocol and the criticality of the whiplash injury is defined. It is seen that the backset distance of the driver head with the headrest and the height difference of the top of the head of the driver with the headrest have a great importance on whiplash injuries.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.4
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• pp.772-776
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• 2005

To support abruptly increasing data traffic in these days, network management is needed. And also to maintain the steady infra, there is MPLS need which can support traffic engineering. It's necessary that MPLS doesn't only manage network to support recently booming data traffic, but has capacity to support traffic engineering to keep static infrastructure. Traffic engineering, method that a large-scale user shifts traffic to the beforehand designated routes that pass through specific nodes on network, is operation that is mapping traffic flow to the physical network topology. In this paper, we supplement the defect of the traditional RSVP traffic engineering and to construct far more steady infra, we suggest the way of its development of ERSVP signaling protocol.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.6
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• pp.1077-1082
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• 2009

Wireless Mesh Network(WMN) is wireless backbone networks technique which has ease of network configuration and cost of advantage. Recently, WNM released a new product, but most of existing research and technology analysis the performance through the simulation. This paper build the wireless mesh network testbed for actual situation. Testbed supports multi-channel multi-interface using bridge, the Wireless Distribution System and dynamic location-based routing protocol. This routing protocol strongly design against wireless interference using metric for link channel change and real distance. Then, the address of mesh clients assigned by the centralized address management server. Mesh clients is designed and implemented to manage network through Simple Network Management Protocol.