• Journal of the Korean Society of Radiology
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• v.12 no.3
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• pp.343-349
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• 2018

Dose rate regulated tracking is known to be an efficient method which adaptively delivers tracking treatments when patient breathing is irregular. The Motion Management Interface (MMI, Varian Medical System, CA), which provides beam on/off switching during treatment is available for clinic. Study is to test if delivering the adaptive tumor tracking is feasible for irregular breathing using beam switching with MMI. 55 free breathing RPM traces acquired from lung cancer patients are used. The first day RPM traces of the patients are utilized to design preprogrammed tracking MLC patterns, of which periods are intentionally reduced by 20% in order to catch up the variation of patient breathing irregularity in the treatment day. Eligibility criteria for this technique are the variation of amplitude and period less than 20%. An algorithm which determines beam on/off every 100 ms by considering the preprogrammed (MLC) positions and current breathing positions is developed. Tracking error and delivery efficacy are calculated by simulating the beam-switching adaptive tracking from the RPM traces. Breathing patterns of 38 patients (70%) met the eligibility criteria. Tracking errors of all of the cases who meet the criteria are less than 2 mm (average 1.4 mm) and the average delivery efficacy was 71%. Those of rest of the cases are 1.9 mm and 48%. Adaptive tracking with beam switching is feasible if patient selection is based on the eligibility criteria.

• Journal of Gastric Cancer
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• v.7 no.4
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• pp.254-260
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• 2007

Purpose: The purpose of this study is to compare the clinicopathological characteristics of stomach and small bowel gastrointestinal stromal tumors and to determine the risk factors and treatment guidelines. Materials and Methods: Among 38 patients who were diagnosed with a gastrointestinal stromal tumor from August 1998 to May 2006, 29 patients at the Pundang Jesaeng General Hospital, Daejin Medical Center were evaluated. The clinicopathological characteristics of gastrointestinal stromal tumors arising from stomach and small bowel were compared. Immunohistochemical staining for CD117, CD34, smooth muscle actin, desmin, and S-100 protein was performed and classified according to NIH criteria. Prognosis between groups was analyzed according to NIH criteria. Results: There was no significant difference in the clinicopathological characteristics and prognosis between gastrointestinal stromal tumors arising from the stomach and small bowel. Recurrence of the disease occurred in four (13.8%) patients. Classification of gastrointestinal stromal tumors according to NIH criteria was predictive of recurrence (P=0.030). Conclusion: NIH criteria were predictive of recurrence, but the location of the primary site was not predictive of recurrence. A further study involving multi center data and a long-term follow-up will be needed for formulating diagnostic and therapeutic guidelines.

• Korean Journal of Construction Engineering and Management
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• v.9 no.5
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• pp.159-167
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• 2008

This study provides a effective approach to the construction management problem with the limited number or amount of available resources using the analytic hierarchy process. Construction management is a series of decision making processes for planning and controling of cost, time and quality as main objectives in construction works. When several activities need the limited same resource at the same time, it is very hard to decide the priority of the activities in the real situations. For that the scientific decision making method and procedure for resource allocation are required. This study solves the resource allocation problem by dealing with the decision making problem which the activities are distributed to multiple projects and under multiple criteria. The analytic hierarchy process is a method devised to solve complex multi-criteria decision problems. The result shows that this study can be effectively used to make decisions in situations involving multiple objectives by evaluating the prioritized ranking and degree of the activity alternatives based on the overall preferences.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.6
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• pp.1581-1585
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• 2007

To report Sensitivity and specificity about utility as diagnosis criteria for deficiency of Qi in stroke. Korean medicine doctor surveyed deficiency of Qi of the symptoms for the Stroke case report form in stroke patients within 1 month of onset. We analyzed 643 patients have diagnosed stroke, neurological deficit continued over twenty-four hours and within one month of onset, except traumatic cerebrovascular attack (EDH, SDH) using the result by medical specialist and residents diagnosed differentiation and written CRF(Case Report Forms) which based on 'Korean Standard Differentiation of the Symptoms and Signs II' in twenty multi centers. The sensitivity of "more 1/5 in major sings and 1/5 in helpful signs", "more 1/5 in major signs and 2/5 in helpful signs", "more 2/5 in major signs and 1/5 in helpful signs", "more 2/5 in major signs and 2/5 in helpful signs""more 3/5 in major signs and 1/5 in helpful signs""more 3/5 in major signs and 2/5 in helpful signs" are respectively 83%, 50%, 72%, 46%, 47%, 32%. The specificity are respectively 28%, 59%, 55%, 74%, 80%, 89%. The sensitivity(72%) and specificity(55%) of "more 2/5 in major signs and 1/5 in helpful signs" that to be implanted. Although this values are not high, after values of sensitivity and specificity should be more than current value, and then we should be able to suggest as objective diagnosing criteria.

• Korean Journal of Radiology
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• v.21 no.7
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• pp.812-828
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• 2020

Objective: To provide an evidence-based guide for the MRI interpretation of complete tumor response after neoadjuvant chemoradiation therapy (CRT) for rectal cancer using visual assessment on T2-weighted imaging (T2) and diffusion-weighted imaging (DWI). Materials and Methods: PubMed MEDLINE, EMBASE, and Cochrane Library were searched on November 28, 2019 to identify articles on the following issues: 1) sensitivity and specificity of T2 or DWI for diagnosing pathologic complete response (pCR) and the criteria for MRI diagnosis; 2) MRI alone vs. MRI combined with other test(s) in sensitivity and specificity for pCR; and 3) tests to select patients for the watch-and-wait management. Eligible articles were selected according to meticulous criteria and were synthesized. Results: Of 1615 article candidates, 55 eligible articles (for all three issues combined) were identified. Combined T2 and DWI performed better than T2 alone, with a meta-analytic summary sensitivity of 0.62 (95% confidence interval [CI], 0.43-0.77; I² = 80.60) and summary specificity of 0.89 (95% CI, 0.80-0.94; I² = 92.61) for diagnosing pCR. The criteria for the complete response on T2 in most studies had the commonality of remarkable tumor decrease to the absence of mass-like or nodular intermediate signal, although somewhat varied, as follows: (near) normalization of the wall; regular, thin, hypointense scar in the luminal side with (near) normal-appearance or homogeneous intermediate signal in the underlying wall; and hypointense thickening of the wall. The criteria on DWI were the absence of a hyperintense signal at high b-value (≥ 800 sec/mm²) in most studies. The specific algorithm to combine T2 and DWI was obscure in half of the studies. MRI combined with endoscopy was the most utilized means to select patients for the watch-and-wait management despite a lack of strong evidence to guide and support a multi-test approach. Conclusion: This systematic review and meta-analysis provide an evidence-based practical guide for MRI assessment of complete tumor response after CRT for rectal cancer.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.3A
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• pp.375-382
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• 2000

Equalization of satellite communication using Complex-Bilinear Recurrent Neural Network(C-BLRNN) is proposed in this pater. Since the BLRNN is based on the bilinear polynomial and it has been more effectively used in modeling highly nonlinear systems with time-series characteristics than multi-layer perception type neural networks(MLPNN) , it can be applied to satellite equalizer. the proposed C-BLRNN based equalizer for M-PSK with a channel model is compared with Volterra filter Equalizer, DFE, and conventional Complex MLPNN Equlizer. The results show that the proposed C-BLRNN based equalizer gives very favorable results in both of MSE and BER criteria over other equalizers.

• Journal of the Korean housing association
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• v.17 no.4
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• pp.131-143
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• 2006

Nowadays, diverse mass media discovers and introduces outstanding management cases of apartment complexes to induce vital competitions of constructors and active participation of residents to apartment management. This study statistically analyzed the management issues of outstanding apartment complexes that have been introduced by mass media with lexical criteria to examine the characteristics of their exemplary management. The key issues of outstanding apartment management are summarized as: efficient management of convenient facilities for residents, community activities based on residents' participation, and maintenance of pleasant living environments through transparent management. Also, the result of the relation arrangement of co-occurrence word from a Social Network Analysis included three key concepts of multi-family housing management - Maintenance Management, Operating Management, and Community Life Management - with emphasis on 'residents' and 'apartment complexes.' However, Operating Management was relatively deemphasized.

• Journal of the Korea Institute of Building Construction
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• v.6 no.3 s.21
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• pp.67-73
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• 2006

This study aims to evaluate the feasibility of remodeling business by predicting the future price of apartment house after remodeling using Hedonic Price Model. The data concerning such 9 independent variables as location, unit size, unit plan, landscape, parking, the number of elapsed years after completion, number of units, mechanical performance, interior from 25 regions in Seoul metropolitan city were collected and evaluated by established evaluation criteria. The coefficients affecting the price of apartment unit were made by Ivay of linear multi-regression and put into Hedonic Price Model. The feasibility evaluation model for apartment was made and verified by data of remodelled apartment. The predicted results using suggested evaluation model coincide with actual apartment market situations.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.403-407
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• 2009

In this work, finite element investigations were carried out to manufacture a seamless aluminum liner without crack generation using four-stage deep drawing followed by two-stage ironing process. In order to predict the crack generation during the liner manufacturing process, the Normalize Cockroft-Latham(NCL) which is one of ductile fracture criteria was adopted. In addition, the tensile tests were carried out to obtain the critical value of NCL by comparing the experimental and FE simulation results. From this, various case studies based on FE simulation were carried to obtain the optimum die designs which can prevent the crack generation during ironing processes. Finally, the aluminum liner was successfully made using obtained die designs so that requirements were met in terms of thickness and height of the liner.

• Korean Journal of Computational Design and Engineering
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• v.15 no.2
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• pp.144-156
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• 2010

When existing parts are re-used for the development of a new product or business-to-business transactions, a method for searching parts from a part database that meets user's requirements is necessary. To this end, it is important to develop a part search method which is able to measure similarity between parts and user's input data with generality as well as robustness. In this paper, the authors suggest a method for measuring part similarity using ontology and multi-criteria decision making method and address its technical details. The proposed method ensures the interoperability with existing engineering information management systems, represents part specifications systematically, and has generality in the procedure for comparing part specifications. The case study for ejector pins having been conducted to demonstrate the proposed method is also discussed.