• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.750-752
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• 2010

MANET has some interest as a wireless mobile network supporting node mobility and having no additional infrastructure. Speed of mobile node on MANET is various from just slow speed of human's walk to vehicle's moving speed. In this study, VoIP performance of MANET is evaluated in the view of speed of mobile node. VoIP performance is studied on walking speed, vehicle speed and higher speed on MANET. PDR(Packet Delivery Ratio), MOS(Mean Opinion Score) are used as performance parameters.

• Journal of Sensor Science and Technology
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• v.21 no.5
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• pp.379-384
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• 2012

This paper presents the power source of wireless sensor node (WSN) using supercapacitors and a solar cell. Supercapacitors have high lifetime cycling compared to that of batteries. Supercapacitors are connected in series to achieve higher voltage and a voltage balancing circuit is required to ensure that no individual cell goes overvoltage. We employ an active balancing circuit that draws minimal current by using transistors. A diode is connected in series with each supercapacitor. A new balancing circuit that equalize the cells-voltage reduces energy consumption of supercapacitors. Voltage of operating WSN is applied 2.2-3.3V by DC/DC converter and supercapacitor voltage 2.2-5.1V. Maximum operating time of wireless sensor node is about 16 hours in full charging.

• Fashion & Textile Research Journal
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• v.1 no.1
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• pp.50-55
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• 1999

The repeatability of fabric drape was studied. Two methods for draping were used and the relation between node distributions was investigated using statistical analysis. With this, the relationship between node distribution and fabric mechanical properties was studied. The repeated measurements showed that there was no evidence that fabric has intrinsic node number and the mechanical properties influence on the number of nodes.

• The KIPS Transactions:PartC
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• v.19C no.2
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• pp.83-90
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• 2012

MANET(Mobile Ad-Hoc Network) has a weakness from a security aspect because it operates where no wired network is built, which causes the exposed media, dynamic topology, and the lack of both central monitoring and management. It is especially difficult to detect and mitigate a malicious node because there is not a mediator which controls the network. This kind of malicious node is closely connected to the routing in the field of study of Ad-Hoc security. Accordingly this paper proposes the method on how to enhance the security for the safe and effective routing by detecting the malicious node. We propose MBC(Identification technition of Malicious Behavior node based on Collaboration in MANET) that can effectively cope with malicious behavior though double detecting the node executing the malicious behavior by the collaboration between individual node and the neighbor, and also managing the individual nodes in accordance with the trust level obtained. The simulation test results show that MBC can find the malicious nodes more accurately and promptly that leads to the more effectively secure routing than the existing method.

• Fashion & Textile Research Journal
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• v.11 no.3
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• pp.453-459
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• 2009

The purpose of this study was to provide the basic knowledge to determine the proper seam finish according to the design of sewing products. Four seam finishes(no seam finishes, over-edged seam finishes, turned-and-stitched seam finishes, and bias-bound seam finishes) were constructed with seams in warp, weft and bias directions of the fabric. Using a drape measurement system involving two 18cm diameter supporting disks and a digital camera, the images of draped specimens were captured and processed. Drape behavior was evaluated in terms of drape coefficient, node number, and drape profile. Drape coefficients of the fabrics increased with seam formation and varied by the seam finishes, however no significant differences in drape coefficients by the seam finishes were observed on the heavier fabric. Node numbers of heavier fabric were more deeply affected by the seam finishes than those of lighter fabric. The specimens with turned-and-stitched seam finishes and bias-bound seam finishes showed significantly smaller node numbers compared to the specimens with no seam finishes and over-edged seam finishes on heavier fabric. The length of the seamed part showed positive correlation with the weight of the specimens and negative correlation with the number of nodes in each seam direction. The maximum length of all draped specimens was found in the same direction as the seam direction. In the case of the lighter fabric, the seam and the seam finish had a great influence on the shape of the draped profile.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.3
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• pp.133-138
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• 2016

Objectives: To assess the association between muscle invasion by oral squamous cell carcinoma of the posterior mandibular alveolar ridge and cervical lymph node metastasis on the basis of preoperative magnetic resonance imaging (MRI). Materials and Methods: Twenty-six patients with oral squamous cell carcinoma of the posterior mandibular alveolar ridge were evaluated by MRI. The associations between cervical lymph node metastasis and independent factors evaluated by MRI were analyzed. Overall survival was also analyzed in this manner. Representative biopsy specimens were stained with anti-podoplanin and anti-CD34 antibodies. Results: Mylohyoid muscle invasion was associated with cervical lymph node metastasis. A combinational factor of mylohyoid and/or buccinator muscle invasion was also associated with cervical lymph node metastasis. Cervical lymph node metastasis and masticator space invasion had a negative effect on overall survival. No lymphatic vessels were identified near the tumor invasion front within the mandible. In contrast, lymphatic vessels were identified near the front of tumor invasion in the muscles. Conclusion: This study demonstrates an association between muscular invasion by oral squamous cell carcinoma of the posterior mandibular alveolar ridge and cervical lymph node metastasis.

• Radiation Oncology Journal
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• v.32 no.3
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• pp.132-137
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• 2014

Purpose: To evaluate non-sentinel lymph node (LN) status after sentinel lymph node biopsy (SNB) in patients with breast cancer and to identify the predictive factors for disease failure. Materials and Methods: From January 2006 to December 2007, axillary lymph node (ALN) dissection after SNB was performed for patients with primary invasive breast cancer who had no clinical evidence of LN metastasis. A total of 320 patients were treated with breast-conserving surgery and radiotherapy. Results: The median age of patients was 48 years, and the median follow-up time was 72.8 months. Close resection margin (RM) was observed in 13 patients. The median number of dissected SNB was two, and that of total retrieved ALNs was 11. Sentinel node accuracy was 94.7%, and the overall false negative rate (FNR) was 5.3%. Eleven patients experienced treatment failure. Local recurrence, regional LN recurrence, and distant metastasis were identified in 0.9%, 1.9%, and 2.8% of these patients, respectively. Sentinel LN status were not associated with locoregional recurrence (p > 0.05). Close RM was the only significant factor for disease-free survival (DFS) in univariate and multivariate analysis. The 5-year overall survival, DFS, and locoregional DFS were 100%, 96.8%, and 98.1%, respectively. Conclusion: In this study, SNB was performed with high accuracy and low FNR and high locoregional control was achieved.

• Journal of Chest Surgery
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• v.31 no.11
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• pp.1081-1084
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• 1998

Background: Esophageal surgery in esophageal cancer has low curative resection rate and its resut has not improved even after the extended lymphnode dissection. To evaluate the effectiveness of cervical lymph node dissection, we compare the node of cervical lymph node metastasis in patients esophageal cancer. Materials and methods: We studied a series of 32 patients who underwent operation for thoracic esophageal carcinoma at our institution. The 25 patient who underwent curative surgery were divided into two groups. Both groups A and B underwent transthoracic esophagectomies with mediastinal and abdominal lymphadenectomies only, but group B also underwent bilateral lower neck node dissection. Results: The rate of operative complications did not differ significantly between two groups. No operative and hospital mortalities were noted in either group. However, the mean anesthetic time was significantly longer in group B(mean: 90 minutes). Neck node metastasis was revealed in 27% of group B. Conclusions: Therfore, neck node dissection is meaningful for surgical treatment of the thoracic esophageal carcinoma. The longterm survival rate should be compared later.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.6
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• pp.1251-1255
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• 2011

In this paper, we propose an optimal path search algorithm that contains all nodes using genetic algorithm. An object in this approach is formed as an equation related with the Euclidean distance between an intermediate node and the starting node and between an intermediate node and the goal node. Like other genetic algorithm structures, our algorithm defines a fitness function and selects a crossover spot node and a bitwise crossover point. A new node out of such operation survives only if it satisfies the fitness criteria and that node then becomes the starting node for the next generation. Repetition continues until no changes are made in the population. The efficiency of this proposed approach is verified in the experiment that it is better than two other contestants - sequential approach and the random approach.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.987-993
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• 2020

This study investigated the effective harvest of 'Kyoho' grapevines by examining their characteristics including bud development, necrosis types and flower primordium formation. The size of the axillary bud did not show any difference in the 5th node or more, but it was smaller because it was closer to the base in the 4th node or less. In the 1st node, the rates of main bud necrosis (MBN), accessory bud necrosis (ABN), and whole bud necrosis (WBN) were high, and the rate of flower primordium formation was low, but there was no significant difference in the other nodes. Therefore, it was expected that using other nodes than the 1st node would be advantageous to secure production. Because the growth progresses after sprouting, the main bud necrosis rate increases, showing a very low flower primordium formation rate in March of the following year. Therefore, a method is needed to increase the storage nutrients in the winter and the rate of flower primordium formation after March. This study found that the thickness of the shoots should be less than 8.5 mm between the 3rd and 4th nodes, and the length should be less than 60 cm for nodes up to the 10th node.