• Journal of Korea Multimedia Society
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• v.16 no.9
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• pp.1077-1088
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• 2013

As broadcasting is the process that a node sends a packet to all nodes in the network. it is basic process used for discovering of a routes to a node and disseminating of control information message in Mobile Ad hoc NETwork (MANET). In this paper, we propose dynamically adjusted probabilistic mechanism based on distance ratio and node density for broadcasting in MANETs. The distance ratio can be calculated as the ratio of the radio strength length to the distance from sender of a node, and node density can be get from 1-hop nodes of neighbours. A mobile node receiving broadcast packets determines the probability of rebroadcasting considering distance ratio and node density of itself. Rebroadcast probability will be set as low value to a node which is located in nearby area of sender and has high 1-hop node density, So it reduces packets transmission caused by the early die-out of rebroadcast packets. Compared with the simple flooding and fixed probabilistic flooding by simulation, our approach shows better performances results. Proposed algorithm can reduce the rebroadcast packet delivery more than 30% without scanting reachability, where as it shows up to 96% reachability compared with flooding.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.47-59
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• 2014

In this paper, I propose a new energy efficient clustering scheme to prolong the network lifetime by reducing energy consumption at the sensor node. It is possible that a node determines whether to participate in clustering with certain probability based on local density. This scheme is useful under the environment that sensor nodes are deployed unevenly within the sensing area. By adjusting the probability of participating in clustering dynamically with local density of nodes, the energy consumption of the network is reduced. So, the lifetime of the network is extended. In the region where nodes are densely deployed, it is possible to reduce the energy consumption of the network by limiting the number of node which is participated in clustering with probability which can be adjusted dynamically based on local density of the node. Through computer simulation, it is verified that the proposed scheme is more energy efficient than LEACH protocol under the environment where node are densely located in a specific area.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.583-587
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• 2013

This study aimed to investigate tumor microvessel density (MVD) and lymphatic vessel density (LVD) using the Chalkley method as predictive markers for the risk of axillary lymph node metastasis and their relationship to other clinicopathological parameters in primary breast cancer cases. Forty two node-positive and eighty node-negative breast cancers were immunostained for CD34 and D2-40. MVD and LVD were counted by the Chalkley method at x400 magnification. There was a positive significant correlation of the MVD with the tumor size, coexisting ductal carcinoma in situ (DCIS) and lymph node metastases (P<0.05). In multivariate analysis, the MVD (2.86-4: OR 5.87 95%CI 1.05-32; >4: OR 20.03 95%CI 3.47-115.55), lymphovascular invasion (OR 3.46, 95% CI 1.13-10.58), and associated DCIS (OR 3.1, 95%CI 1.04-9.23) independently predicted axillary lymph node metastasis. There was no significant relationship between LVD and axillary lymph node metastasis. However, D2-40 was a good lymphatic vessel marker to enhance the detection of lymphatic invasion compared to H and E staining. In conclusion, MVD by the Chalkley method, lymphovascular invasion and associated DCIS can be additional predictive factors for axillary lymph node metastases in breast cancer. No relationship was identified between LVD and clinicopathological variables, including axillary lymph node metastasis.

• The KIPS Transactions:PartC
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• v.12C no.4 s.100
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• pp.535-542
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• 2005

This paper proposes an on-demand ad hoc routing protocol, Node Density Based Routing (NDBR), which enhances the routing performance applying a new method to establish alternate patlis. It is important to reserve alternate paths for the route from source to destination in mobile ad hoc networks that are susceptible to failure due to the movement or the power exhaustion of mobile nodes. NDBR aims to establish a route that contains more alternate paths toward the destination by involving intermediate nodes with relatively more adjacent nodes in a possible route, and introduces a new routing criterion called 'node density.' This approach can localize the effects of route failures, and reduce control traffic overhead and route reconfiguration time by enhancing the reachability to the destination node without source-initiated route re-discoveries at route failures. This paper describes the route setup procedure using node density and the route re-configuration procedures employing alternate path information at the intermediate nodes. We show the performance of our routing schemes through a series of simulations using the Network Simulator 2 (ns-2).

• Structural Engineering and Mechanics
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• v.51 no.5
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• pp.793-808
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• 2014

The goal of this study is to evaluate and design steel plates with optimal material distributions achieved through a specific material topology optimization by using a CCARAT (Computer Aided Research Analysis Tool) as an optimizer, topologically optimally updating node densities as design variables. In typical material topology optimization, optimal topology and layouts are described by distributing element densities (from almost 0 to 1), which are arithmetic means of node densities. The average element densities are employed as material properties of each element in finite element analysis. CCARAT may deal with material topology optimization to address the mean compliance problem of structural mechanical problems. This consists of three computational steps: finite element analysis, sensitivity analysis, and optimality criteria optimizer updating node densities. The present node density based design via CCARAT using node densities as design variables removes jagged optimal layouts and checkerboard patterns, which are disadvantages of classical material topology optimization using element densities as design variables. Numerical applications that topologically optimize reinforcement material distribution of steel plates of a cantilever type are studied to verify the numerical superiority of the present node density based design via CCARAT.

• IEMEK Journal of Embedded Systems and Applications
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• v.10 no.6
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• pp.381-390
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• 2015

The efficient design of a transport protocol contributes to energy conservation as well as performance improvement in wireless sensor networks (WSNs). In this paper, a node-density-aware transport protocol (NDTP) for intra-cluster transmissions in WSNs for monitoring physical attributes is proposed, which takes node density into account to mitigate congestion in intra-cluster transmissions. In the proposed NDTP, the maximum active time and queue length of cluster heads are restricted to reduce energy consumption. This is mainly because cluster heads do more works and consume more energy than normal sensor nodes. According to the performance evaluation results, the proposed NDTP outperforms the conventional protocol remarkably in terms of network lifetime, congestion frequency, and packet error rate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.2
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• pp.155-160
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• 2002

Oral squamous cell carcinoma (OSCC), the most common head and neck cancer, shows poor prognosis as a result of frequent local invasion and lymph node metastasis that is mediated by multiple proteolytic enzymes and angiogenesis. In recent reports, angiogenesis is known to play an important role in tumor invasion and metastasis. The purpose of this study was to determine the role of angiogenesis in OSCCs, particularly with respect to the invasive and the metastatic potential. The microvessel density (CD31) in 34 human OSCC cases were investigated by immunohistochemistry, and reviewed with respect to the invasiveness and the presence of lymph node metastasis and following results were obtained. The blood vessel density $(28.8{\pm}7.9)$ in the strong invasive cases were significantly higher than those $(23.3{\pm}6.9)$ in the weak invasive cases. (p<0.05) In the 14 cases with lymph node metastasis, the average blood vessel density was $28.5{\pm}9.6$. On the other hand, in the 20 cases without lymph node metastasis, the blood vessel density was $25.2{\pm}6.4$. The blood vessel density was not statistically related to lymph node metastasis. (p>0.05) These results suggest that angiogenesis may be related to the local invasion of OSCC and further research will be needed to investigate the possibility that antiangiogenic agent can be used as an anticancer agent for OSCC.

• Journal of Computing Science and Engineering
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• v.11 no.2
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• pp.39-48
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• 2017

Main content extraction of web pages is widely used in search engines, web content aggregation and mobile Internet browsing. However, a mass of irrelevant information such as advertisement, irrelevant navigation and trash information is included in web pages. Such irrelevant information reduces the efficiency of web content processing in content-based applications. The purpose of this paper is to propose an automatic main content extraction method of web pages. In this method, we use two indicators to describe characteristics of web pages: text density and hyperlink density. According to continuous distribution of similar content on a page, we use an estimation algorithm to judge if a node is a content node or a noisy node based on characteristics of the node and neighboring nodes. This algorithm enables us to filter advertisement nodes and irrelevant navigation. Experimental results on 10 news websites revealed that our algorithm could achieve a 96.34% average acceptable rate.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.105-107
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• 2015

In this paper, we proposed LTD(Load Tolerance Density-distribution) algorithm using dynamic density for analyzing distribute routing path. MANET(Mobile Ad-hoc Networks) consists of the node that has a mobility. By the Mobility, the topology is exchanged frequently. To reduce the exchange of topology, the hierarchy network is studied. However, if the load is concentrated at the cluster head node, the communication is disconnected. the proposed algorithm measure the dynamic density of the node using poisson distribution. And this algorithm provides distribute routing path using dynamic density. The simulation results, the proposed algorithm shows improved packet delivery ratio than the compared algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.11
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• pp.2196-2204
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• 2015

Location-based density information of mobile node could be used well in various, new and expanding areas such as location-based services, internet of things, smart grid technologies, and intelligent building. In general, receiving mobile nodes of a wireless mobile node depend on the maximum communication range of transmitting mobile node. In this paper, efficient computing method for mobile node using Delaunay triangulation is proposed, which is irrespective of mobile node's maximum communication range and reflect relative location in a given situation. Proposed method may be good used to find out the density of network constructed by various max communication range devices as Internet of Things. This method suggested in this paper could work well for location-based services, internet of things, smart grid technologies, and intelligent building.