• Journal of the Korea Society for Simulation
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• v.20 no.4
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• pp.21-29
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• 2011

Wireless sensor nodes operate in open environments. The deployed sensor nodes are very vulnerable to physical attacks from outside. Attackers compromise some sensor nodes. The compromised nodes by attackers can lead to false data injection into sensor networks. These attacks deplete the limited energy of sensor nodes. Ye et al. proposed the Statistical En-Route Filtering (SEF) as a countermeasure of the attacks. The sensor node in SEF examines the event reports based on certain uniform probability. Thus, the same energies are consumed in both legitimate reports and false reports. In this paper, we propose a method that each node controls the probability of attempts to verify a report to reduce energy consumption of sensor nodes. The probability is determined in consideration of the remaining energy of the node, the number of hops from the node to SINK node, the ratio of false reports. the proposed method can have security which is similar with SEF and consumes lower energy than SEF.

• Steel and Composite Structures
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• v.23 no.6
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• pp.737-746
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• 2017

In this paper the influence of aspect ratio, height ratio and material angle on static and free vibration behaviour of orthotropic elliptic paraboloid shells is studied by using a four-node hybrid stress finite element. The formulation of the element is based on Hellinger-Reissner variational principle. The element is developed by combining a hybrid plane stress element and a hybrid plate element. A parametric study is carried out for static and free vibration response of orthotropic elliptic paraboloid shells with respect to displacements, internal forces, fundamental frequencies and mode shapes by varying the aspect and height ratios, and material angle.

• Structural Engineering and Mechanics
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• v.37 no.6
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• pp.633-648
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• 2011

This paper investigates the aspect-ratio locking of the isoparametric 8-node quadrilateral (QUAD8) element. An important finding is that, if finite element solution is carried out with in exact arithmetic (i.e., with no truncation and round off errors), the locking tendency of the element is completely avoided even for aspect-ratios as high as 100000. The current finite element codes mostly use floating point arithmetic. Thus, they can only avoid this locking for aspect-ratios up to 100 or 1000. A novel method is proposed in the paper to avoid aspect-ratio locking in floating point computations. In this method, the offending terms of the strain-displacement matrix (i.e., $\mathbf{B}$-matrix) are multiplied by suitable scaling factors to avoid ill-conditioning of stiffness matrix. Numerical examples are presented to demonstrate the efficacy of the method. The examples reveal that aspect-ratio locking is avoided even for aspect-ratios as high as 100000.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1997.10a
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• pp.254-261
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• 1997

In desingin plate bridges, the width-thickness ratio of flanges and webs are proportioned in such that the premature local buckling of flanges and webs prior to achievement of the full strength of plate-girders must be prevented. It is the common practive in most design codes that the flange local buckling strength and the web bend buckling strength are separately computed. In most practical plate girders, however, the flange buckles simultaneously when web bend-buckling occurs, vice versa. The primary purpose of the present study is to investigate the phenomenon, which may be called flange-web interactive buckling. Using the eight-node shell element available in the commercial multi-purpose program ABAQUS, the phenomenon was quantitatively investigated. Also presented are the effects of various factors such as the ratio of flange slenderness ratio to the web slenderness ratio, the ratio of flange width to the web depth, and the longitudinal stiffeners. A series of comparative studies with various design codes show that the present study provides more accurate and effective design basis in proportioning the flanges and webs.

• Korean Journal of Medicinal Crop Science
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• v.11 no.2
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• pp.97-101
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• 2003

The purpose of this experiment is to improve the ratio of female flower in Schizandra chinensis Baillon. The experiment was carried out in two purposes. One was to understand the development stages on bud formation and determining sex after bud formation by stage. The other was to investigate characteristics of flowers forming on spring when summer pruning was taken place in different cutting part and timing in S. chinensis Baillon. The outcome was that on 7th of June the flower bud was found next to leaf primordium in branch of this year and no changes were found in shape for two weeks by 26th July. On 26th of June, an ovule that forms organ was observed and then, an ovule was found after sex was determined on 6th of July. Second experiment was carried out to find out when the sex was determined by adapting different pruning methods; cutting the branch at 6th node on June 1, June 15, and July 1; cutting the branch at 10th node on June 15, and July 1. The result was that the re-growth ratio on the branch 6th node was cut on June 1 and June 15. July 1 was 34-56% and, however, the number of setting flowers and mail flowers were fewer than the normal branches. More over, even though the re-growth ratio of branches were 34-25% when the cutting was taken place at 10th node on June 15 and July 1, the number of setting flowers and mail flowers were the same as the non treated branch. As a result, it is assumed that cutting controlling in this plant to increase the number of female flowers has no effect.

• Journal of the Korea Society of Computer and Information
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• v.12 no.3
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• pp.165-175
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• 2007

The mobile agent executes a given task by which the agent code moves to the server directly. Therefore, node migration method becomes an important factor which impact on the whole performance of distributed system. In this paper, we propose an adaptive migration path technique of mobile agent using the metadata of naming agent. In this proposed technique, node selection for migration depends on the content of referenced metadata, and the reliability of migrated information is determined by the metadata updating method and cooperative operations of individual agents in multi-agents system. For these, we design the metadata using by the number of hit documents, hit ratio, node processing time and network delay time, and describe the methods for creating, using and updating metadata for which determine the adaptive node migration path of mobile agent according to the cooperation of individual agents and number of hit documents using by designed metadata. And results of evaluated performance for proposed adaptive migration path technique through the proper experiment and analysis gain rate of high effective information earning, because of high hit ratio(72%) about of fathered documents by case of applying metadata move to the 13 nodes. But, in case of non-applying metadata is hit ratio(46%) of gathered documents and rate of effective information earning about of 26 nodes is 36.8%.

• Journal of Chest Surgery
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• v.50 no.5
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• pp.329-338
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• 2017

Background: The clinical value of 3-field lymph node dissection (3FLND) in esophageal squamous cell carcinoma (ESCC) remains controversial. This study aimed to identify the patterns and prognostic significance of cervical lymph node metastasis (CLNM) in ESCC. Methods: A retrospective review of 77 patients with E SCC who underwent esophagectomy and 3FLND between 2002 and 2016 was conducted. For each cervical node level, the efficacy index (EI), overall survival, recurrence rate, and complication rate were compared. Results: CLNM was identified in 34 patients (44.2%) who underwent 3FLND. Patients with CLNM had a significantly lower overall survival rate (22.7% vs. 58.2%) and a higher recurrence rate (45.9% vs. 16.3%) than patients without CLNM. CLNM was an independent predictor of recurrence in ESCC patients. Moreover, in patients with pathologic N3 tumors, the odds ratio of CLNM was 10.8 (95% confidence interval, 2.0 to 57.5; p=0.005). Level IV dissection had the highest EI, and level IV metastasis was significantly correlated with overall survival (p=0.012) and recurrence (p=0.001). Conclusion: CLNM was a significant prognostic factor for ESCC patients and was more common among patients with advanced nodal stages. Level IV exhibited the highest risk of metastasis, and dissection at level IV may be crucial when performing 3FLND, especially in advanced nodal stage disease.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.16-25
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• 1995

The effects of leaf removal time on variation of nodal sink components in determinated soybean ［Glycine max （L.） Merr.］ cultivar 'Danyeobkong' were measured at the experiment field of Chonbuk Provincial Rural Development Administration in 1991. Node order in this experiment was calculated from terminal node to bottom node to clarify the photosynthetic ability of canopy leaves. The upper 5 leaves from terminal node of main stem were removed at 5, 15, 25, 35 and 45 days after flowering(DAF) respectively. In spite of light-receiving increment in lower part of main stem and in branch by removing the upper part leaves of main stem, seed weight of that part was not increased in leaf removal treatment compared with control block. The node position reducing pod went down from terminal to bottom by delaying leaf removal time, and the influence of pod number reduction was bigger in DAF 25 than in DAF 15. But the seed number reduction per pod was the biggest in DAF 35. Cracked seed coat ratio ranged from 25% to 35% in control block, while that of leaf removal block had mostly 10% gap compared with the control block.rol block.

• Korean Journal of Head & Neck Oncology
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• v.11 no.2
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• pp.125-131
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• 1995

The authors present 15 cases in which the diagnosis of thyroid cancer was established pathologically among 300 cases of Graves' disease diagnosed clinically at Chosun University Hospital, from January 1982 to December 1994. These cases were analyzed in order to establish guidelines for prophylactic node dissection as part of the initial management of thyroid cancer in patients with Graves' disease. The analysis revealed the following: 1) The average age of the 15 patients was 34.5 years and the male: female ratio was 1 : 4.0. 2) In 8 of the 15 cases(53.5 %) the occult thyroid carcinoma measured less than 1.5cm. 3) The degree of invasivensess manifested in these fifteen cases may be summarized as follows: In Group 1(6 cases) there was absence of microscopic capsular invasion and of lymphnode metastasis. In Group 11(4 cases) threre was microscopic capsular invasion but absence of lymphnode metastasis: In Group III(4 cases) there was either extrathyrodal soft tissue invasion or regional lymph node metastasis: and in Group IV(1 case) there was lymphnode invasion and distant metastasis. 4) Thirteen patients underwent either subtotal or near total thyroidectomy, and 2 patients underwent total thyroidectomy. Seven patients underwent some type of neck dissection, as follows: anterior compartment dissection in one of the cases in Group I; functional neck dissection in two cases and jugular node dissection in one case in Group II; and anterior compartment dissection in one case and modified radical neck dissection in two cases in Group III. 5) The author propose the following guidelines for prophylactic initial node dissection when a unexpected coexisting thyroid carcinoma in encountered on the frozen section during the surgical management of Graves' disease; Group I cases do not require initial neck dissection in group II, anterior compartment dissection in sufficient. In Group III, either jugular node dissection or functional neck dissection should be performed, and followed by postoperative Ra$^{131}$I therapy, Group IV requires Ra$^{131}$I therapy with or without modified radical neck dissection depending in the patient's condition.

• The KIPS Transactions:PartC
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• v.17C no.3
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• pp.259-270
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• 2010

In this paper, a Location Information-based Gradient Routing (LIGR) algorithm is proposed for setting up routing path based on physical location information of sensor nodes in wireless ad-hoc networks. LIGR algorithm reduces the unnecessary data transmission time, route search time, and propagation delay time of packet by determining the transmission direction and search range through the gradient from the source node to sink node using the physical location information. In addition, the low battery nodes are supposed to have the second or third priority in case of forwarding node selection, which reduces the possibility of selecting the low battery nodes. As a result, the low battery node functions as host node rather than router in the wireless sensor networks. The LIGR protocol performed better than the Logical Grid Routing (LGR) protocol in the average receiving rate, delay time, the average residual energy, and the network processing ratio.