• Journal of Korea Multimedia Society
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• v.22 no.6
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• pp.676-683
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• 2019

Wireless Sensor Networks (WSNs) consist of multiple tiny and power constrained sensors which use radio frequencies to carry out sensing in a designated sensor area. To effectively design and implement reliable WSN, it is critical to consider models, protocols, and algorithms that can optimize energy consumption of all the sensor nodes with optimal amount of packet delivery. It has been observed that deploying a single sink node comes with numerous challenges especially in a situation with high node density and congestion. Sensor nodes close to a single sink node receive more transmission traffic load compared to other sensors, thus causing quick depletion of energy which finally leads to an energy hole and sink hole problems. In this paper, we proposed the use of multiple energy efficient sink nodes with brute force technique under optimized parameters to improve on the number of packets delivered within a given time. Simulation results not only depict that, deploying N sink nodes in a sensor area has a maximum limit to offer a justifiable improvement in terms of packet delivery ratio but also offers a reduction in End to End delay and reliability in case of failure of a single sink node, and an improvement in the network lifetime rather than deploying a single static sink node.

• Korean Journal of Veterinary Service
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• v.23 no.3
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• pp.263-269
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• 2000

This study was carried out to set a standard of damage compensation by researching state of damage due to noises in laying and prelaying hens. Recently, there are many damage cases in chicken farms near construction site that were caused by noises of construction. Therefore disputes and complaints about economical loss have increased ceaselessly. But we have few research and report such a thing. The result have shown that the weight loss rate was ranged from 9.48% to 23.2% and mortality of laying period of hens was higher than prelaying period. Pathological findings were fatty liver, congestion and hemorrhage of intestine, erosion of proventriculus and gizzard in order of case frequency. And these signs in hens of laying period was more serious than prelaying period. Half-life rate of antibody titers against Newcastle disease and infectious bronchitis in sound stressed hens was no different compared with non-stressed hens. Egg production rate dropped from 38% to 45% according to strength of noises. Before being stressed, hens produced special, large, middle, small-size eggs in the order. But after being stressed, their egg Production rate of middle, small-size Increased while egg production rate of special, large-size decreased. Production rate of soft and broken shell eggs was 0.015% in the stressed flocks higher than 0.005% in the non-stressed flocks.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.493-501
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• 2016

In-network storage is an effective technique for avoiding network congestion and reducing power consumption in continuous data collection in wireless sensor networks. In recent years, network coding based storage design has been proposed as a means to achieving ubiquitous access that permits any query to be satisfied by a few random (nearby) storage nodes. To maintain data consistency in continuous data collection applications, the readings of a sensor over time must be sent to the same set of storage nodes. In this paper, we present an efficient approach to updating data at storage nodes to maintain data consistency at the storage nodes without decoding out the old data and re-encoding with new data. We studied a transmission strategy that identifies a set of storage nodes for each source sensor that minimizes the transmission cost and achieves ubiquitous access by transmitting sparsely using the sparse matrix theory. We demonstrate that the problem of minimizing the cost of transmission with coding is NP-hard. We present an approximation algorithm based on regarding every storage node with memory size B as B tiny nodes that can store only one packet. We analyzed the approximation ratio of the proposed approximation solution, and compared the performance of the proposed coding approach with other coding schemes presented in the literature. The simulation results confirm that significant performance improvement can be achieved with the proposed transmission strategy.

• Radiation Oncology Journal
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• v.7 no.2
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• pp.157-169
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• 1989

Radiological and clinical evidences indicate that hyperthermia combined with irradiation produce a significant improvement in therapeutic effect of cancer The experiences obtained from 90 rats' kidney A single dose of irradiation ranged from 6Gy, 8Gy and 10Gy was delivered on the rat's kidney. The combined therapy group had the same irradiation after hyperthermia at $42\~44^{\circ}C$ for 30 minutes. Microscopic examination and calculation of thermal enhancement ratio were carried out, and the results were as follows: 1. In the group of hyperthermia alone, there were moderate glomerular congestion and mild tubular degeneration on light microscopic examination. 2. In the group of irradiation alone, tubular degeneration was noted in 6Gy irradiation and its severity was increased along with radiation dose. 3. In the group of hyperthermia combined with irradiation, tubular degeneration and necrosis were appeared in 6Gy and 10Gy irradiation, respectively. 4. On electron microscopic examination, proximal convoluted tubular and glomerular changes in irradiation group were similar to that of combined with hyperthermia, and its severity was increased along with observation periods. 5. Thermal enhancement ratio (TER) was 1.0 after evaluation of histipathologic changes in rat's kidney, with combination therapy.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.329-343
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• 2019

In order to simulate the evacuation simulation of a ship during a sinking, the slope angle change of the ship must be reflected during the simulation. In this study, the passenger evacuation simulation is implemented by continuously applying the heeling angle change during sinking. To reflect crowd behavior, the human density and the congestion algorithm were developed in this research and the walking speed experiment in the special situation occurring in the inclined ship was conducted. Evacuation simulation was carried out by applying the experimental results and the change of the walking speed according to the heeling angle of the ship. In order to verify the evacuation simulation, test items suggested by International Maritime Organization (IMO) and SAFEGUARD Validation Data Set conducted on a large Ro-PAX ferry (SGVDS 1) which performed real evacuation trial in full-scale ships were performed and the results of simulation were analyzed. Based on hypothetical scenario of when a normal evacuation command is delivered to the passengers of MV SEWOL in time, we predicted and analyzed the evacuation process and the number of casualties.

• Journal of Chest Surgery
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• v.17 no.1
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• pp.32-40
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• 1984

During the past six years from July 1977 to June 1983, fifteen adult patients of patent ductus arteriosus were surgically treated. The results were as follows: 1. Of the 15 patients, their age range was 17 to 34 years with a mean of 24 years, and sexual predominance was women [9. cf. 6 men]. 2. The most common symptom showed exertional dyspnea, and 10 patients were classed in NYHA class II, the rest were all class III. 3. On physical examination, all patients were auscultated continuous murmur, but concomitantly diastolic murmur was noted apical region in 2 patients. 4. On roentgenogram of chest, normal finding was 3 patients, and the other patients were revealed the evidence of pulmonary congestion. 5. The electrocardiogram was normal in 6 patients, but LVH was seen in 5, and 2 patients were LVH+ LAH. 6. Cardiac catheterization was performed in 12, and mean value of SO2[LPA-RV] was 6.3%, Q/Q 2.09, peak systolic pulmonary arterial pressure 45.3 mmHg, and Rp/Rs 0.365. 7. All operations were carried out by posterolateral thoracotomy. In 6 patients, division and suture of ductus were possible, the other patients were treated by division and ligation with heavy silk or Dacron patch. 8. Postoperative complications were hoarseness, persistent murmur, reoperation for bleeding, and atelectasis. Early and late mortality was 20% [3 patients], and cause of death was mainly aneurysmal rupture of previous operative site.

• Journal of Navigation and Port Research
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• v.27 no.5
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• pp.479-486
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• 2003

The concept of “Environmental Stress(ES)” can be used as a useful index when assessing the maritime traffic safety. It is composed of two parts, one due to geographical restriction and another one due to traffic congestion. In this paper, Environmental Stress due to geographical restriction is reviewed Its characteristics are surveyed from the sample calculation results for some hypothetical cases, such as approaching a breakwater, navigating in a long straight channel, and in a long bended channel. Sample calculations are also carried out for the approach channels in Busan and Kwangyang harbor. By using this ES concept, it is expected that objective ana quantitative assessment of safety is possible for various environmental conditions when navigating in a harbor or in a fairway.

• Journal of the Korea Society of Computer and Information
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• v.9 no.3
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• pp.195-200
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• 2004

The change of traffic by the CDV is entered in a condensed form in UUC/NPC, overflowing the buffer of the net and possibly causing its congestion. For this reason this paper proposes the Cell Spacing Scheme. As the Cell Shaping Scheme, two method is proposed ; RAT based on the time in which cells enter the spacer and RDT based on the time in which cells come out from the spacer. This paper proposes the improved spacing sheme in which the departure time of the present cell determines the departure time of the next one, by combining with Leaky Bucket and on the traffic characteristics of ATM network.

• Journal of Fashion Business
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• v.20 no.5
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• pp.30-44
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• 2016

In this study, we used the Q methodology, which is considered an effective way to identify and assess the characterization of the human subjective consciousness, and we intended to carry out a scientific approach to classify cosmetics consumers in a department store. The purpose of this study is to identify the dimension of recognition and the characterization of Korean women who use a department store, as well as to classify cosmetics consumers in a department store. The analyzed data was divided into the top 10 questions and 10 sub-items, and it was then classified into six consumer types, depending on typicality of three factors. The three factors were 'effectiveness', 'goal' and 'congestion of shopping'. We named and analyzed the features of each type through in-depth Q workshops in which 22 professionals participated. This study is meaningful as it used the Q-methodology instead of statistics which had been used before to classify the consumers, so that the 'subjective' estimation was analyzed into 'objective' types. The results of this study are expected to be useful for creating a marketing strategy for the cosmetics industry.

• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.161-166
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• 1997

From January of 1991 to December of 1992, 42 chickens collected from 21 poultry farms and also diagnosed as necrotic enteritis(NE) was examined clinical signs, gross and histopathological findings. Main clinical signs were characterized by decreased appetite, mild to severe depression, reductance to move, ruffled feathers, greenish to yellow-browinish diarrhea sometimes including blood. As progressed, diseased chickens showed feces mixed with necrotic debris which detached from the intestinal mucosa and mostly resulted in the death. In chronic cases, there were dirty feathers around cloaca due to diarrhea and notably retarded growth. Principle gross lesions were usually confined to the jejunum and ileum, especially toward the lower part of Meckel's diverticulum. The part of small intestine was frequently distended with gas, and also showed mucosal congestion and hemorrhages with varying degrees. Sometimes, the intestinal mucosa was thickened, and also covered with fibronecrotic psuedomembrane. In addition, there were focal necrosis and severely multifocal ulcreation in the mucosa of small intestine. Major histopathological findings included villous necrosis and erosion of the small intestine covering with lots of bacterial colonies, inflammatory cell infiltration in the lamina propria, and dilatation and hyperplasia of crypts. Luminal exudate contained bacterial colonies, fibrin, erythrocytes, and desquamated epithelium. Thirteen(61.9%) out of 21 NE-occurring farms were complicated with intestinal coccidiosis.