• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.11
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• pp.2091-2098
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• 2006

In this paper, it proposes a protocol of resource adaptive data dissemination for sensor nodes in a wireless sensor network. In general, each sensor node used in a wireless sensor network delivers the required information to the final destination by conducting cooperative works such as sensing, processing, and communicating each other using the battery power of a independent sensor node. So, a protocol used for transferring the acquired information to users through the wireless sensor network can minimize the power consumption of energy resource given to a sensor node. Especially, it is very important to minimize the total amount of power consumption with a method for handling the problems on implosion. data delivery overlapping, and excessive message transfer caused by message broadcasting. In this paper, for the maintaining of the shortest path between sensor nodes, maximizing of the life time of a sensor node and minimizing of communication cost, it presents a method for selecting the representative transfer node for an event arising area based on the negotiation scheme and maintaining optimal transfer path using hop and energy information. Finally, for the performance evaluation, we compare the proposed protocol to existing directed diffusion and SPIN protocol. And, with the simulation results, we show that the proposed protocol enhances the performance on the power consumption rate when the number of overall sensor nodes in a sensor network or neighbor sensor nodes in an event area are increased and on the number of messages disseminated from a sensor node.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.11-19
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• 2010

ZigBee is a standard for wireless personal area networks(WPANs) based on the IEEE 802.15.4 standard. It has been developed for low cost and low power consumption. There are two alternative routing schemes that have been proposed for the ZigBee standard: Ad-hoc On-Demand Distance Vector(AODV) and tree routing. The tree routing forwards packets from sensors to a sink node based on the parent-child relationships established by the IEEE 802.15.4 MAC topology formation procedure. In order to join the network, a sensor node chooses an existing node with the strongest RSSI(Received signal strength indicator) signal as a parent node. Therefore, some nodes carry a large amount of traffic load and exhaust their energy rapidly. To overcome this problem, we introduce a new metric based on link quality and traffic load for load balancing. Instead of the strength of RSSI, the proposed scheme uses the new metric to choose a parent node during the topology formation procedure. Extensive simulation results using TOSSIM(TinyOS mote SIMulator) show that the CFR scheme outperforms well in comparison to the conventional tree routing scheme.

• Journal of Gastric Cancer
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• v.4 no.4
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• pp.272-276
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• 2004

Purpose: The incidence of nodal metastases is as low as 2 to $20\%$ in early gastric cancer, so there is a trend to lessen the extent of surgery. In addition, the adequate range for a lymphadenectomy is controversial, especially in early gastric cancer. In this study, we tried to find the minimal range for a lymphadenectomy by analyzing sentinel-node and solitary lymph-node metastases in gastric cancer. Materials and Methods: The total of 78 patients who underwent a curative gastrectomy with a D2 lymphadenectomy for early gastric cancer between 2000 and 2002 in the Department of Surgery, Yonsei University, Seoul, Korea, were included for the evaluation of sentinel-node metastases.. After a laparotomy, 25 mg of indocyanine green was mixed in 5 ml of normal saline, and all the dye was injected into the subserosal layer around the primary tumor. All nodes stained within 5 minutes were marked. In addition, a total of 141 patients, who underwent a curative gastrectomy between 1997 and 2001 at the Department of Surgery, Yonsei University, Seoul, Korea, were analyzed for solitary lymph- node metastases. Results: Among the 78 patients, sentinel nodes were detected in 69 patients ($88.5\%$). The sentinel nodes in 60 cases ($87.0\%$) were located in the perigastric area. However, 9 cases ($13.0\%$) had sentinel nodes in the N2 group. In the 141 cases that had a solitary metastatic node, 125 cases ($88.6\%$) demonstrated the metastatic lymph node in the perigastric area, and 16 cases ($11.4\%$) showed that the metastatic node in the N2 group. Conclusion: Taken together, removal of a perigastric lymph node could miss early metastases in gastric cancer, so a D1 lymphadenectomy should not be the minimal range of dissection if a lymphadenectomy is necessary. (J Korean Gastric Cancer Assoc 2004;4:272-276)

• Journal of the Korean Institute of Gas
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• v.25 no.5
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• pp.78-87
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• 2021

This paper analyzes the range and attributes of the traffic information service between domestic public institutions and private companies, and suggests the possibility of joint application of node-link information for each company and the possibility of joint use of private traffic information. For this purpose, the present condition and attributes of domestic and foreign traffic information node-links (link length, node ID number, U-turn information, lane information, left turn information, right turn information, etc.) were analyzed. The analysis targets, the node-link of the national standard node and the two companies were analyzed. The area of the experiment was selected in Jongno-gu, Seoul, where standard-link information is complex, traffic volume is high, and various standard-links exist. The experiment was conducted by comparing and analyzing the traffic information attributes of three types of node-links and performing node-links overlapping matching (utilizing encoding_decoding method), and the possibility of matching node-links and attributes of different specifications was analyzed using Open LR technique.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.406-413
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• 2020

This study was conducted to find out optimum fruiting node order, pinching node order, and harvesting time in hydroponics using coir substrates to produce high quality melon (Cucumis melo L.) fruit. Three plants per coir slab (100 × 20 × 10 cm) were planted for each treatment. Yamazaki standard nutrient solutions for melon were supplied with 1.8, 2.0, and 2.3 dS·m^-1 at the early, middle (fruit enlargement step), and late growth stages, respectively. Two cultivars of 'PMR Dalgona' and 'Earl's Aibi' were used for fruiting node order and pinching node order experiments. Fruiting node treatments were conducted three replications (8-10 ^th, 11-13 ^th, and 14-15 ^th nodes) and pinching node treatments treated with three replications (18 ^th, 21 ^th, and 24 ^th nodes). Two cultivars of 'PMR Dalgona' and 'Earl's Crown' were used for fruit harvesting time experiment and treated with in four replications (45, 50, 55, and 60 days after fruiting). In growth characteristics, the leaf width and leaf area of 'PMR Dalgona' were the greatest 28.2 cm and 10,845 ㎠. Respectively, 11-13 ^th fruiting nodes or more. The node length of 'Earl's Aibi' was the longest by 147.6 cm at 11-13 ^th fruiting nodes. For fruit quality characteristics, the fruit weight of 'Earl's Aibi' at 11-13 ^th fruiting node fruiting was the greatest by 2.0 kg. The soluble solids content (SSC) of 'PMR Dalgona' was the highest by 14.5 °Brix at 8-10 ^th nodes in fruiting node orders and 14.5 °Brix at the 24 ^th pinching node order, respectively with significant difference. The SSC tends to increase in the same for both cultivars of 'PMR Dalgona' and 'Earl's Aibi' as the position of fruiting node was lower. The SSC and fruit weight of melon harvested at 55-60 days after fruiting was the best. From the results of this study, most of SSC tends to increase in the lower position of fruiting node order and the higher pinching node order, whereas the fruit weight shows a tendency of increasing with higher fruiting node. In addition, the SSC of fruit increased as the number of days after fruiting increased, and further research is needed for more various cultivars. In melon hydroponics using coir substrates, it is needed to figure out the characteristics of each cultivar to determine optimum fruiting node order, pinching node order, and fruit harvest time.

• Journal of Korea Multimedia Society
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• v.10 no.10
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• pp.1347-1355
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• 2007

A sensor network is composed of a large number of tiny devices, scattered and deployed in a specified regions. Each sensing device has processing and wireless communication capabilities, which enable it to gather information from the sensing area and to transfer report messages to a base station. The energy-efficient routing paths are established when the base station requests a query, since each node has several characteristics such as low-power, constrained energy, and limited capacity. The established paths are recovered while minimizing the total transmit energy and maximizing the network lifetime when the paths are broken. In this paper, we propose a routing algorithm that each sensor node reports its adjacent link information to the sink node when a sink node broadcasts a query. The sink node manages the total topology and establishes routing paths. This algorithm has a benefit to find an alternative path by reducing the negotiating messages for establishing paths when the established paths are broken. To reduce the overhead of collection information, each node has a link information before reporting to the sink. Because the node recognizes which nodes are adjacent. The proposed algorithm reduces the number of required messages, because sensor nodes receive and report routing messages for establishment at the beginning of configuring routing paths, since each node keeps topology information to establish a routing path, which is useful to report sensing tasks in monitoring environments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.4
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• pp.618-636
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• 1997

DQDB(Distributed Queue Dual Bus) protocol, the IEEE 802.6 standard protocol for metropolitan area networks, does not fully take advantage of the capabilities of dual bus architecture. Although fairness in bandwidth distribution among nodes is improved when using so called the bandwidth balancing mechanism, the protocol requires a considerable amount of time to adjust to changes in the network load. Additionally, the bandwidth balancing mechanism leaves a portion of the available bandwidth unused. In a high-speed backbone network, each node may act as a bridge/ router which connects several LANs as well as hosts. However, Because the existence of high speed LANs becomes commonplace, the congestionmay occur on a node because of the limitation on access rate to the backbone network and on available buffer spaces. to release the congestion, it is desirable to install some congestion control algorithm in the node. In this paper, we propose an efficient congestion control mechanism and fair and waster-free MAC protocol for dual bus network. In this protocol, all the buffers in the network can be shared in such a way that the transmission rate of each node can be set proportional to its load. In other words, a heavily loaded node obtains a larger bandwidth to send the sements so tht the congestion can be avoided while the uncongested nodes slow down their transmission rate and store the incoming segments into thier buffers. this implies that the buffers on the network can be shared dynamically. Simulation results show that the proposed probotol significantly reduces the segment queueing delay of a heavily loaded node and segment loss rate when compared with original DQDB. And it enables an attractive high throughput in the backbone network. Because in the proposed protocol, each node does not send a requet by the segment but send a request one time in the meaning of having segments, the frequency of sending requests is very low in the proposed protocol. so the proposed protocol signigificantly reduces the segment queuing dely. and In the proposed protocol, each node uses bandwidth in proportion to its load. so In case of limitation of available buffer spaces, the proposed protocol reduces segment loss rate of a heavily loaded node. Bandwidth balancing DQDB requires the wastage of bandwidth to be fair bandwidth allocation. But the proposed DQDB MAC protocol enables fair bandwidth without wasting bandwidth by using bandwidth one after another among active nodes.

• Journal of Plant Biotechnology
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• v.29 no.1
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• pp.37-40
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• 2002

Sweet potato is a crop vegetatively propagated by vine cuttings, an ineffective method for maintaining pathogene-free stock plants. As an alternative method, single-node cultures of virus-free plantlets derived from apical meristem in sweet potato (cv. Yulmi) was examined. Effective pH range, sugar concentration and nodal order were investigated to establish an in vitro mass propagation system with high quality virus-free stock plantlets to farmhouse. Although the plantlets grew at wide range of pH, the most effective pH of the medium was 4.8 in single-node cultures. High sugar concentration of 60∼80 g/L resulted in increased growth response in shoot length, root length, number of node, leaf area and fresh and dry weight of shoot and root, whereas reducing sugar contents below 6% was showed reduced growth response. The first node including meristem tip was the best for the rapid growth of plantlets and the other nodes also showed a very similar growth response. Uniform plantlet can be obtained massively at the same time by culture of single node except for the first node including meristem tip. In conclusion, the most effective pH range and sugar concentration of medium for the growth of plantlets via single-node cultures was 4.8, 60∼80 g/L respectively. The first node was the best for the rapid propagation of plantlets in nodal order.

• Korean Journal of Head & Neck Oncology
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• v.31 no.2
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• pp.39-42
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• 2015

Warthin's tumor is the second most common salivary gland benign tumor, typically occurring in the fifth to seventh decades of life which shows an indolent feature. It is usually found in the parotid gland but occasionally in extra-parotid locations such as peri-parotid lymph node. However, Report of solitary Warthin's tumor in cervical lymph node is unusual. We here report a case of 72-year-old male with simultaneous malignant melanoma on eyelid and cervical lymph node enlargement in cervical level II area thus mimicking malignancy metastasis. After excisional biopsy under the local anesthesia, pathology was reported as papillary cystadenoma lymphomatosum, which is a histologically pathognomic finding of Warthin's tumor. However, there was no suspicious tumorous lesion in major or minor salivary glands. This case suggests that Warthin's tumor should be considered as a possible pathology in solitary lymph node lesion of neck.

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.175-180
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• 1992

Giant lymph node hyperplasia(Castleman's disease) is a rare disease, which represents a peculiar form of lymph node hyperplasia. Generally, it has been considered as benign and localized disease but recently, revealed malignant transformation in some cases of multicenteric form. It usually occurs on the mediastinum and occasionaly neck, lung, axilla, mesentery, broad ligament, retroperitoneum or soft tissue of extremities. Histopathologically, it is divided into hyaline vascular or plasma cell type and the former is characterized with prominent vascular proliferation and hyalinization in the central portion and tight concenteric layering of lymphocytes at the periphery of the fillicles(mantle zone) and the latter is characterized by a diffuse plasma cell proliferation in the interfollicular area. From the point of view of clinical presentation, it has been divided into solitary form, which presents as a localized mass located most commonly in the mediastinum, and multicenteric form, which occurs multiple location and has systemic manifestation arid transformation into malignancy. Herein we report a case of Giant lymph node hyperplasia occuring in the left spermatic cord in a 58-year old male with brief review of literatures.