• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.6
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• pp.68-76
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• 2008

It is difficult to maintain mutes in the mobile ad hoc network (MANET) due to the high probability of disconnected routes break by frequent change of topology. The links can have the different reliability about data transmission due to these characteristics. Hence a measure which can evaluate this reliability and a algorithm which reflects this are required. In this paper, we propose routing algorithm based on reliability about transmission. First the bayesian inference which infers the hypothesis by past information is considered to obtain the link's transmission reliability. The other is that the link-based reliability estimation model which considers each link's reliability additionally is proposed while the standard uses only Dijkstra's shortest path algorithm. the simulation results using NS-2 show that the performance of proposed algorithm is superior to the standard OLSR in terms of throughput and stability.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.5
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• pp.1-11
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• 2008

Wireless Sensor Networks is applied to improvement of life convenience or service like U-City as well as environment pollution, tunnel and structural health monitoring, storm, and earthquake diagnostic system. To increase the usability of sensor data and applicability, mobile devices and their facilities allow the applications of sensor networks to give mobile users and actuators the results of event detection at anytime and anywhere. In this paper, we present MUSNEMO(Multi-sensor centric Ubiquitous Smart sensor NEtwork using Mobile devices) developed system for providing more efficient and valuable information services with a variety of mobile devices and network camera integrated to WSN. Our system is performed based on IEEE 802.15.4 protocol stack. To validate system usability, we built sensor network environments where were equipped with five application sensors such magnetic, photodiode, microphone, motion and vibration. We also built and tested proposed MUSNEMO to provide a novel model for event detection systems with mobile framework.

• Steel and Composite Structures
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• v.23 no.2
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• pp.143-152
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• 2017

This paper focuses on the seismic performance of pallet-type steel storage rack structures in their down aisle direction. As evidenced by experimental research, the seismic response of storage racks in the down-aisle direction is strongly affected by the nonlinear moment-rotation response of the beam-to-column connections. In their down-aisle direction, rack structures are designed to resist lateral seismic loads with typical moment frames utilizing proprietary beam-to-column moment-resisting connections. These connections are mostly boltless hooked type connections and they exhibit significantly large rotations resulting in large lateral frame displacements when subjected to strong ground motions. In this paper, typical hooked boltless beam-to-column connections are studied experimentally to obtain their non-linear reversed cyclic moment-rotation response. Additionally, a compound type connection involving the standard hooks and additional bolts were also tested under similar conditions. The simple introduction of the additional bolts within the hooked connection is considered to be a practical way of structural upgrade in the connection. The experimentally evaluated characteristics of the connections are compared in terms of some important performance indicators such as maximum moment and rotation capacity, change in stiffness and accumulated energy levels within the cyclic loading protocol. Finally, the obtained characteristics were used to carry out seismic performance assessment of rack frames incorporating the tested beam-to-column connections. The assessment involves a displacement based approach that utilizes a simple analytical model that captures the seismic behavior of racks in their down-aisle direction. The results of the study indicate that the proposed method of upgrading appears to be a very practical and effective way of increasing the seismic performance of hooked connections and hence the rack frames in their down-aisle direction.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2739-2742
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• 2013

Background: This survey aim was to evaluate the epidemiology and outcomes of neuroblastoma patients in one the most important children referral hospitals in Iran as a model from developing countries. Materials and Methods: This retrospective, non-randomized analytic study was conducted on 219 newly diagnosed neuroblastoma cases. Results: The age of patients ranged from 1-156 months with the average of $40.5{\pm}2.44$, with a male/female ratio of 1.9/1. Of the total, 172 (78.5%) were children and 47 (21.5%) were infants The adrenals were the most common primary site (60%). Stage 4 at diagnosis accounted for about 54% of all enrolled patients. Infants had significantly better cumulative survival ($85{\pm}8%$) than children ($33{\pm}7%$) during the follow up period and the survival rate improved from $33{\pm}7%$ in 1974-1994 to $58{\pm}9%$ in 1995-2005. Conclusions: This study indicates that our patient population with neuroblastomas tends to have more advanced disease, perhaps with poor biologic markers, but our analysis shows that the outcomes have improved over 32 years although the overall survival of Iranian neuroblastoma patients is still lower than developed countries. Late diagnosis, inability to determine risk group during the years of study and using single protocol for all enrolled patients can be the reasons of lower survival rate.

• Journal of Advanced Navigation Technology
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• v.18 no.4
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• pp.393-400
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• 2014

With developed countries, nationally the supply and development of electric vehicle(EV) has been going at a rapid pace. Now, the charger specifications, charging methods and standardization of communication protocols is going in each country and a lot of company are involved in the business about those. To popularize it as existing car, it is required to build the network and infrastructure which is proper for domestic environment. It should also need to be able to develop standardized protocols can be beyond the construction of the protocol of the upper stage server and charger, and is used in a residential environment actually applied to related industries. Therefore, in this paper, we propose a home network model of EV that raised the need for a study of the charging system for EV, using M2M technology and multi-charging system tailored to the residential environment of our country.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.709-712
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• 2007

There have been researches into digital Watermarking technology or Fingerprinting vigorously to safeguard Protective rights for knowledge and poverty for digital contents. DRM(Digital Rights Management) is not only Protective rights for knowledge and poverty, but also management and systems that are necessary to put out, circulate and use for contents. This paper proposes two kinds of ideas. One is protecting contents from illegal acts such as illegal copies when the contents are in the process of circulation. The other is the protocol that can give users convenience. Hidden Agents are used so that contents are protected from illegal copies and illegal use in the contents and cuts off those illegal acts. The Agent will be installed without any special setup. In addition, it can replace roles of Watermarking as a protection. Therefore, this paper shows the solution of illegal copies that happens frequently.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.11A
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• pp.1051-1058
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• 2010

Mobile IP (MIP) and SIP are considered as important technologies to provide the macro mobility in the next generation mobile convergence networks which have heterogeneous access networks. Typically, MIP and SIP are more suitable for the non-real-time TCP connections and the real-time RTP/UDP sessions respectively, hence a handset which uses both of these sessions should simultaneously apply MIP and SIP to perform the efficient mobility management. Existing multi-layered mobility management schemes focus on the signalling order of each protocol. However, simple combining of two protocols cannot provide the performance enhancement of the mobility management. In this paper, a novel multi-layered mobility management algorithm using the combination of SIP and fast MIPv6 (FMIPv6) is proposed. FMIPv6 and SIP mobility is simultaneously performed to reduce the service interrupt time and to guarantee QoS requirement. The delay model is defined to analysis the performance of the algorithm and the simulation results show the performance of the proposed algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11B
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• pp.1142-1150
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• 2009

In this paper, we propose an novel bandwidth scheduling algorithm for the MAC protocol employed by the Data Over Cable Service Interface Specifications (DOCSIS) 3.0 compliant cable networks. The proposed algorithm statistically improves the chances of request piggybacking to minimize the access delay. It utilizes the piggyback request feature of the segment packets that has been newly specified in DCOSIS 3.0. In DOCSIS 3.0, a bandwidth request can be granted to several upstream channels within an upstream bonding group. The grant on each individual channel is treated as a segment packet. We find the optimal segment placement to minimize the access delay in the proposed algorithm. We also use a self-similar traffic model for simulation and analysis to evaluate the performance of the proposed algorithm.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.3
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• pp.301-305
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• 2008

Races must be detected for debugging OpenMP programs with directives, because they may cause unintended nondeterministic results of programs. Intel Thread Checker, an existing tool that can detects races, can not verify the existence of races and is often time-consuming and tends to require large space. To solve these problems, we developed a tool that verifies the existence of races using user requirements and analyzed model of programs. However, the tool does not have optimal performance in programs which have no synchronization for interthread coordination. This paper presents an optimal tool that applies the optimum labeling and protocol for program models without interthread coordination. For synthetic programs without interthread synchronization, the tool verifies races over 250 times faster than the previous tool on the average, even if the maximum parallelism increases in every case of which the number of total accesses are identical.

• Composites Research
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• v.31 no.1
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• pp.37-41
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• 2018

The aim of the current work is to characterise a piecewisely-integrated composite bumper beam based on the IIHS bumper crash protocol. IIHS bumper crash FE analysis for an aluminium type bumper beam was carried out to get the information about the dominant loading types at several regions in the bumper beam during crash. In the meantime, robust stacking sequences against tension and compression have been searched for using FE analysis of a coupon type model. After determining most effective stacking sequences for tension and compression, three-point bending simulation was preliminarily carried out to investigate the combination performance of them. Finally, IIHS bumper crash FE analysis for the piecewisely-integrated composite bumper beam, which consisted of the combination of tension effective stacking sequence and compression efficacious stacking sequence, was conducted and the result was compared with other types of composite bumper beams. It was found that the newly suggested piecewisely-integrated composite bumper beam showed superior crashworthy behaviour to those of uni-modal stacking sequence composite bumper beams.