• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.3
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• pp.111-118
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• 2002

In this paper, FEM analysis is performed in order to estimate the behavior of RC columns retrofitted with Carbon Fiber Sheet(CFS). Two node truss element and four node isometric plate bond element are used for modeling the CFS and the adhesion between concrete and CFS, respectively. Five specimens with different quantity of CFS are analyzed and compared with experimental results. From the comparison, analytical results show a good agreement with the test results. Therefore, it is advisable to use the FEM used in this paper to predict the behavior of columns with CFS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.129-132
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• 2001

The ad hoc network was composed of Mobile hosts. Due to the limited transmission range of each mobile node hosts, in such an environment, it is essential for other hosts to coorperate to transfer packet to destination. Moreover, the existing routing protocol algorithms are not efficient on the ad hoc network because a mobile host operates router without fixed router. In this paper, we will compare and analysis for the performance of existing ad hoc network routing protocols through simulation.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.28.3-28
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• 2001

This paper proposes a new algorithm that detects and separates the occluding and occluded objects in a 2D image. An input image is represented by the attributed graph where a node corresponds to a surface and an arc connecting two nodes describes the adjacency of the nodes in the image. Each end of arc is weighted by relation value which tells the number of edges connected to the surface represented by the node in the opposite side of the arc. In attributed graph homogeneous nodes pertained to the same object always construct one of three special patterns which can be simply classified by comparison of relation values of the arcs. The experimental results have shown that the proposed algorithm efficiently separates the objects ...

• Korean Journal of Bronchoesophagology
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• v.16 no.2
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• pp.109-114
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• 2010

Background: The aim of this study was to compare a novel mannose receptor-binding agent(Technetium-99m human serum albumin, $^{99m}Tc$-MSA) with $^{99m}Tc$-phytate for sentinel node mapping in patients with esophageal cancer. Material and Method: Twenty patients with clinical stage T1N0m0 or T2N0M0 esophageal cancer that were candidates for esophagectomy were enrolled. Endoscopic injection of $^{99m}Tc$-MSA or $^{99m}Tc$-phytate was administered at the peri-tumor region before surgery in 10 patients. The radioactive lymph nodes were identified with a handheld gamma probe after lymph node dissection. Results: The patient's age and the sex ratio of both groups were similar. The clinical stage, tumor location, and operative technique did not differ. The total number of dissected lymph nodes did not differ ($28.5{\pm}9.12$ in MSA group, $32.2{\pm}11.24$ in phytate group, p=0.430). The sentinel node was identified in all cases in both groups. The number of sentinel nodes per patient was $2.7{\pm}1.57$ in the MSA group, which was significantly greater than the $1.7{\pm}0.88$ in the phytate group (p=0.036). Five out of 20 patients whose sentinel nodes could be identified had metastases; however, neither group had any false-negative results for sentinel node identification. Conclusion: Sentinel nodes were detected more frequently with MSA than with phytate.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.9
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• pp.751-764
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• 2013

In cognitive radio ad-hoc networks, common control channel overload and packet collisions are occured due to indiscriminate broadcasting of control packets. So that the path reliability is reduced and control channel is easily saturated. In this paper, we propose a new routing algorithm considering the probability of appearance of primary user and channel status of neighbor nodes. When the source node needs to transmit a data packet to the destination, it performs route discovery process by exchanging control messages using a control channel in ADOV CR Ad-hoc networks. If any intermediate node doesn't have common data channel with previous node to transmit data, it doesn't rebroadcast control packet. And if it has common data channels with previous node, each node determines channel contribution factor with the number of common channels. Based on the channel contribution factor, each node performs different back-off broadcasting. In addition, each node controls control packet flooding by applying to proposed advanced mode using such as number of available channels and channel stability. With the proposed method, the number of control packets to find the data transmission path and the probability of collision among control packets can be decreased. While the path reliability can be increased. Through simulation, we show that our proposed algorithm reduces packet collisions in comparison with the traditional algorithm.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.6
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• pp.2889-2909
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• 2017

Wireless sensor networks (WSNs) have attracted lots of attention in recent years due to their potential for various applications. In this paper, we seek how to efficiently deploy relay nodes into traditional static WSNs with constrained locations, aiming to satisfy specific requirements of the industry, such as average energy consumption and average network reliability. This constrained relay node deployment problem (CRNDP) is known as NP-hard optimization problem in the literature. We consider addressing this multi-objective (MO) optimization problem with an improved Artificial Bee Colony (ABC) algorithm with a linear local search (MOABCLLS), which is an extension of an improved ABC and applies two strategies of MO optimization. In order to verify the effectiveness of the MOABCLLS, two versions of MO ABC, two additional standard genetic algorithms, NSGA-II and SPEA2, and two different MO trajectory algorithms are included for comparison. We employ these metaheuristics on a test data set obtained from the literature. For an in-depth analysis of the behavior of the MOABCLLS compared to traditional methodologies, a statistical procedure is utilized to analyze the results. After studying the results, it is concluded that constrained relay node deployment using the MOABCLLS outperforms the performance of the other algorithms, based on two MO quality metrics: hypervolume and coverage of two sets.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11B
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• pp.1269-1276
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• 2011

In the Proxy Mobile IPv6 (PMIPv6), the data transmission performance may be degraded when the two communicating hosts are located within the same mobile domain, since all the data packet shall be delivered by way of Local Mobility Anchor (LMA). In this paper we propose an extensional scheme of PMIPv6 using binding query. In the proposed Query-based PMIPv6 (Q-PMIPv6) scheme, the Mobile Access Gateway (NAG) of Correspondent Node (CN) sends a binding query to LMA to obtain the Proxy Care-of-Address of Mobile Node (MN). Since then, CN and MN can communicate with each other by using an optimized data path. For comparison, we performed the numerical analysis and the ns-2 simulations for the proposed Q-PMIPv6 scheme and the existing PMIPv6 and PMIPv6 Localized Routing (PMIPv6-LR). From the results, we can see that the proposed scheme outperforms the existing PMIPv6 and PMIPv6-LR schemes in terms of the signaling control and data delivery costs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.8A
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• pp.791-800
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• 2010

Recently wireless sensor networks as a field of ubiquitous computing technology was in the limelight. To use and collect the necessary information, Sink node mobility is essential. TTDD(Two-Tier Data Dissemination) proposed most common technique associated with Mobile sink node in wireless sensor networks, but issues exist that the use of many control packet falls into the energy efficiency. The technique for solving problems is Cluster-Based Energy-efficient Routing protocol (CBPER). But CBPER does not transmit the data correctly to sink node or source node. In this paper, we propose An Energy-Efficient Routing Protocol based on Static Grid using mobile sink nodes in order to solve the data transmission failure and reduce the energy consumption in Wireless Sensor Networks. We have evaluated it with the NS-2 simulator. Our results show that the proposed protocol saves the energy consumption up to 34% in comparison with CBPER. We also prove that the proposed protocol can transmit more accurate data to the sink de than CBPER.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3149-3152
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• 2012

Objective: The prognostic significance of perineural invasion (PNI) in gastric cancer has been previously investigated but not clearly clarified. The objective of our study was to investigate the role of PNI as prognostic factor in patients undergoing curative surgical resection and without distant metastasis in comparison with other clinicopathological factors. Methods: Between 2001 and 2010, 287 cases of gastric adenocarcinoma underwent radical gastrectomy recorded in hospital based registries. PNI was assessed as positive when cancer cells were seen in the perinerium or neural fascicles intramurally. Categorical and continuous variables were summarized using descriptive statistics and compared using chi-square and Mann-Whitney U tests, respectively. Cancer related survival rates were estimated by the Kaplan-Meier method. Results: PNI was positive in 211 of 287 cancers (73%), with a positive relation to lymph node metastases and advanced stage (p=0.0001, p=0.0001, respectively), mural invasion, and lymphatic and blood vessel invasion (p=0.0001, p=0.0001, respectively). The median survival of the PNI positive patients was significantly shorter than that of their PNI negative counterparts (24.1 versus 38.2 months, p=0.008). In the multivariate analysis, we detected PNI was an independent prognostic factor (p=0.025, HR=1.21, 95% CL 1.08-2.3) along with classical clinicopathological variables such as lymph node involvement (p=0.001), pT stage (p=0.03), and LVI (p=0.017), but not age, gender, tumour localization, stage, histologic type, and surgery procedure. Conclusions: PNI positivity in gastric cancers was related mural invasion, lymph node involvement, advanced stage and lymphatic and venous blood vessels. The presence of PNI appeared as an independent prognostic factor on survival on multivariate analysis, not influenced by tumor stage, lymph node metastases and other classical factors.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8595-8601
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• 2014

Background: miR-200a expression is frequently altered in numerous cancers. The aim of the present study was to determine the role of microRNA-200a in advanced ovarian carcinomas. Materials and Methods: We measured miR-200a expression in 72 matched normal ovarian tissues and advanced ovarian carcinomas, and also two ovarian carcinoma cell lines (SKOV3 and SKOV3.ip1 - the latter being more invasive and metastatic than the parental SKOV3) by stem-loop real-time RT-PCR based on TaqMan microRNA assay using U6 as a reference. Levels of miR-200a expression were compared by disease stage, tumor grade, histology, and lymph node involvement. To evaluate the role of microRNA-200a, cell proliferation and invasion of SKOV-3 and SKOV-3.ip1 were analyzed with miR-200a inhibitor/mimic transfected cells. Results: Of 72 paired samples, 65 cancer tissues overexpressed microRNA-200a greater than two fold in comparison with matched normal epithelium. Specifically, patients with lymph node metastasis showed significant elevation. The level correlated with clinicopathological features, including high tumor grade, late disease stage, most notably with lymph node metastasis, but not with tumor histology. In addition, SKOV-3.ip1 cells also overexpressed miR-200a compared with SKOV-3, and miR-200a inhibitor transfected SKOV-3.ip1 cells showed significant reduction in cellular proliferation and invasion, while a miR-200a mimic stimulated the opposite behavior. Conclusions: We provide definitive evidence that miR-200a is up-regulated in a significant proportion of advanced ovarian carcinomas, and that elevated miR-200a expression facilitates tumor progression. Our findings support the notion that miR-200a is an onco-microRNA for ovarian cancer, and elevation is a useful potential diagnostic indicator. This study also provides a solid basis for further functional analysis of miR-200a in advanced ovarian cancer.