• Journal of the Korea Society for Simulation
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• v.18 no.3
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• pp.13-21
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• 2009

The sensor nodes that form a wireless sensor network must perform both routing and sensing roles, since each sensor node always has a regular energy drain. The majority of sensors being used in wireless sensor networks are either unmanned or operated in environments that make them difficult for humans to approach. Furthermore, since many wireless sensor networks contain large numbers of sensors, thus requiring the sensor nodes to be small in size and cheap in price, the amount of power that can be supplied to the nodes and their data processing capacity are both limited. In this paper, we proposes the WSN(Wireless Sensor Network) algorithm which is applied sensor node that has low power consumption and efficiency measurement. Moreover, the efficiency routing protocol is proposed in this paper. The proposed algorithm reduces power consumption of sensor node data communication. It has not researched in LEACH(Low-Energy Adaptive Clustering Hierarchy) routing protocol. As controlling the active/sleep mode based on the measured data by sensor node, the energy consumption is able to be managed. In the event, the data is transferred to the local cluster head already set. The other side, this algorithm send the data as dependent on the information such as initial and present energy, and the number of rounds that are transformed into cluster header and then transferred. In this situation, the assignment of each node to cluster head evenly is very important. We selected cluster head efficiently and uniformly distributed the energy to each cluster node through the proposed algorithm. Consequently, this caused the extension of the WSN life time.

• Fashion & Textile Research Journal
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• v.10 no.5
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• pp.660-667
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• 2008

The purpose of this study was to modify a Flared Skirt for women according to the somatotype of lower body. The subjects for the wear test were 3 students, who were in $mean{\pm}1{\sigma}$ each somatotype. The results of this study are as follows: First, the Flared Skirt pattern was modified according to each type. The front waist line rising measurement proposed for type 1 and type 2 were 0.5cm, because of lower front silhouette with waist shape. The back waist line rising measurement proposed for type 2 was 1cm and type 3 was 0.5cm, because of lower back shape with hip. Second, the wave-height of nodes were regular at front and back in type 1. Also, the wave-height of nodes were evenly distributed side and center. The variation ratio of wave-height of back nodes were lower than existing pattern in type 2 and type 3. It means the variation ratio of wave-height of back nodes were regular in modification pattern. Altogether, modification patterns were more regular and lower than existing pattern in the number of nodes, the distribution ratio of nodes, the wave-height of node, the variation ratio of wave height of nodes.

• Journal of Chest Surgery
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• v.31 no.1
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• pp.59-65
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• 1998

Atrial fibrillation is the most common of all cardiac arrhythmias. It is associated with significant morbidity and mortality and is frequently resistant to medical therapy. On the experimental and clinical study, the presence of macroreentrant circuits and the absence of either microreentrant circuits or evidence of atrial automaticity suggests that atrial fibrillation should be amenable to surgical ablation. The results of the maze III procedure are associated with a higher incidence of postoperative sinus rhythm, improved long-term sinus node function, fewer pacemaker requirements, less arrhythmia recurrence, and improved long-term atrial transport function. We had experienced 4 patients with chronic atrial fibrillation. For the first time, Hioki procedure had been performed in the first patient with ASD and atrial fibrillation, regular sinus rhythm showed on postoperative EKG, but junctional rhythm and bradycardia developed postoperative 3 years. The maze III procedure for the rest with mitral valvular disease and atrial fibrillation had been done, followed by regular sinus rhythm for 2 patients and atrial fibrillation for 1 patient, managed with amiodarone, on immediate postoperative state. Echocardiogram documented good contraction of right atrium and hardly contraction of left atrium for 2 patients with regular sinus rhythm postoperative 3 months.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.9
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• pp.3138-3151
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• 2022

Traffic safety and congestion are becoming more and more serious, especially the frequent occurrence of traffic accidents, which have caused great casualties and economic losses. Cellular Vehicle to Everything (C-V2X) can assist in safe driving and improve traffic efficiency through real-time information sharing and communication between vehicles. All vehicles communicate directly with Base Stations (BS), which will increase the base station load. And when the communicating vehicles are too far apart, too fast or there are obstacles in the communication path, the communication link can be unstable or even interrupted. Therefore, choosing an effective and reliable multi-hop relay-assisted Vehicle to Vehicle (V2V) communication can not only reduce the base station load and improve the system throughput but also expand the base station coverage and improve the communication quality of edge vehicles. Therefore, a communication area division scheme based on regular hexagon segmentation technology is proposed, a relay-assisted V2V communication mechanism is designed for the divided communication areas, and an efficient communication link is constructed by selecting the best relay node. Simulation results show that the scheme can improve the throughput of the system by nearly 55% and enhance the robustness of the V2V communication link.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.1
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• pp.41-48
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• 2013

The aim of the present study is to design a memory-efficient octree for querying large 3D point cloud. The aim has been fulfilled by omitting variables for minimum bounding hexahedral (MBH) of each octree node expressed in C++ language and by passing the re-estimated MBH from parent nodes to child nodes. More efficiency has been reported by two-fold processes of generating pseudo and regular trees to declare an array for all anticipated nodes, instead of using new operator to declare each child node. Experiments were conducted by constructing tree structures and querying neighbor points out of real point cloud composed of more than 18 million points. Compared with conventional methods using MBH information defined in each node, the suggested methods have proved themselves, in spite of existing trade-off between speed and memory efficiency, to be more memory-efficient than the comparative ones and to be practical alternatives applicable to large 3D point cloud.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.6
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• pp.147-152
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• 2016

Wireless sensor networks that are easy to deploy and install are ideal for building a system that monitors the condition of the equipment in a factory environment where wiring is difficult. The ZigBee has characteristics of low price and low power compared with other wireless communication protocols and is suitable for a monitoring system requiring a plurality of nodes. ZigBee communication requires encryption security between devices because all protocol layers are based on OTM trusted by each other. In the communication between nodes, node authentication must be guaranteed and exposure of confidential information managed by each node should be minimized. The facilities of the factory are regular and stationary in distribution location. In order to protect the information gathered from the sensor in the factory environment and the actuator control information connected to the sensor node, we propose a cryptosystem based on the two - dimensional grid - based key distribution method similar to the distribution environment of the facility.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.1
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• pp.55-59
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• 2010

Most applications for solar-powered wireless sensor networks are usually deployed in remote areas without a continuous connection to the external networks and a regular maintenance by an administrator. In this case, sensory data has to be stored in the network as much as possible until it is uploaded by the data mule. For this purpose, a balanced data distribution over the network should be performed, and this can be achieved efficiently by taking the amount of available energy and storage into account, in the system layer of each node. In this paper, we introduce a simple but very efficient data distribution algorithm, by which each solar-powered node utilizes the harvested energy and the storage space maximally. This scheme running on each node determines the amount of energy which can be used for a data distribution as well as the amount of data which should be transferred to each neighbor, by using the local information of energy and storage status.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.6
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• pp.608-618
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• 2000

We consider the problem of placing resources in a distributed computing system so that certain performance requirements may be met while minimizing the number of required resource copies, irrespective of node or link failures. To meet the requirements for high performance and high availability, minimum number of resource copies should be placed in such a way that each node has at least two copies on the node or its neighbor nodes. This is called the fault-tolerant resource placement problem in this paper. The structure of a parallel or a distributed computing system is represented by a graph. The fault-tolerant placement problem is first transformed into the problem of finding the smallest fault-tolerant dominating set in a graph. The dominating set problem is known to be NP-complete. In this paper, searching for the smallest fault-tolerant dominating set is formulated as a state-space search problem, which is then solved optimally with the well-known A* algorithm. To speed up the search, we derive heuristic information by analyzing the properties of fault-tolerant dominating sets. Some experimental results on various regular and random graphs show that the search time can be reduced dramatically using the heuristic information.

• Archives of Craniofacial Surgery
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• v.21 no.6
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• pp.376-379
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• 2020

Supraclavicular lymph node (SCLN) flap is a common donor site for vascularized lymph node transfer for the treatment of lymphedema. Chyle leakage is a rare but serious complication after harvesting SCLN flap in the neck. We report a case of chyle leakage at the SCLN donor site and its successful management. A 52-year-old woman underwent SCLN transfer for treatment of lower extremity lymphedema. After starting a regular diet and wheelchair ambulation on the 3rd postoperative day, the amount of drainage at the donor site increased (8-62 mL/day) with the color becoming milky, which suggested a chyle leak. Despite starting a low-fat diet on the 4th postoperative day, the chyle leakage persisted (70 mL/day). The patient was started on fat-free diet on the 5th postoperative day. The amount of drainage started to decrease and the drain color became more clear within 24 hours. The drainage amount remained less than 10 mL/day from the 8th postoperative day, and we removed the drain on the 12th postoperative day. There was no seroma or other wound complications at follow-up 4 weeks after the operation. The current case demonstrates that a fat-free diet can be a first-line treatment for low output chyle leakage after a SCLN flap.

• Structural Engineering and Mechanics
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• v.11 no.3
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• pp.325-340
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• 2001

This paper addresses an efficient modification method that eliminates the undesirable effects of strains due to various non-conforming modes so that the non-conforming element can pass the patch test unconditionally. The scheme is incorporated in the element formulation to establish new types of non-conforming hexahedral elements designated as NHx and NVHx for the regular element and variable node element, respectively. Non-conforming displacement modes are selectively added to the ordinary (conforming) element displacement assumptions to improve the bending behavior of the distorted solid element. To verify the validation of proposed direct modification method and the improvement of element behavior, several numerical tests are carried out. Test results show that the proposed method is effective and its applications to non-conforming solid elements guarantee for the element to pass the patch test.