• Journal of Korean Neurosurgical Society
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• v.60 no.1
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• pp.75-81
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• 2017

Objective : Spinal deformity surgery has the potential risk of massive blood loss. To reduce surgical bleeding, the use of tranexamic acid (TXA) became popular in spinal surgery, recently. The purpose of this study was to determine the effectiveness of intra-operative TXA use to reduce surgical bleeding and transfusion requirements in spinal deformity surgery. Methods : A total of 132 consecutive patients undergoing multi-level posterior spinal segmental instrumented fusion (${\geq}5$ levels) were analyzed retrospectively. Primary outcome measures included intraoperative estimated blood loss (EBL), transfusion amount and rate of transfusion. Secondary outcome measures included postoperative transfusion amount, rate of transfusion, and complications associated with TXA or allogeneic blood transfusions. Results : The number of patients was 89 in TXA group and 43 in non-TXA group. There were no significant differences in demographic or surgical traits between the groups except hypertension. The EBL was significantly lower in TXA group than non-TXA group (841 vs. 1336 mL, p=0.002). TXA group also showed less intra-operative and postoperative transfusion requirements (544 vs. 812 mL, p=0.012; 193 vs. 359 mL, p=0.034). Based on multiple regression analysis, TXA use could reduce surgical bleeding by 371 mL (37 % of mean EBL). Complication rate was not different between the groups. Conclusion : TXA use can effectively reduce the amount of intra-operative bleeding and transfusion requirements in spinal deformity surgery. Future randomized controlled study could confirm the routine use of TXA in major spinal surgery.

• Journal of the Korea Computer Industry Society
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• v.6 no.3
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• pp.539-550
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• 2005

The spanning tree, which is being used the most widely in indoor wiring network, is chosen for the network topology of the optimal LAN design. To apply a spanning tree to GA, the concept of $Pr\ddot{u}fer$ numbers is used. $Pr\ddot{u}fer$ numbers can express he spanning tree in an efficient and brief way, and also can properly represent the characteristics of spanning trees. This paper uses Pareto Stratum-Niche Cubicle(PS-NC) GA by complementing the defect of the same priority allowance in non-dominated solutions of pareto genetic algorithm(PGA). By applying the PS-NC GA to the LAN design areas, the optimal LAN topology design in terms of minimizing both message delay time and connection-cost could be accomplished in a relatively short time. Numerical analysis has been done for a hypothetical data set. The results show that the proposed algorithm could provide better or good solutions for the multi-objective LAN design problem in a fairly short time.

• The Journal of Industrial Distribution & Business
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• v.5 no.4
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• pp.31-42
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• 2014

Purpose - According to the applied studies knowledge, management implementation can improve organizational performance. The main objective of this study is to develop an understanding of critical success factors that enhance the successful implementation of knowledge management. Research design, data, and methodology - This study used Analytical Hierarchy Procedure (AHP), which is a multi-criteria decision making model that works on fuzzy logic. Using this method, researchers can find the proportion of success due to the contribution of the critical success factors (CSFs). Results - The results show that more than 70% of respondents indicate the possibility of success in knowledge management implementation. Further, the results show that top management support has the greatest relationship with the success of knowledge management implementation. This was followed by information technology, performance measurement, and culture, which had a high relation with knowledge management success. Process and activities have a moderate positive relation, while education and training has a low relation with success. Because of an inappropriate p-value, knowledge management strategies show no relation to the success of knowledge management in the Iranian health Industry. Conclusions - This study was conducted because of a critical issue in the Iranian health industry that indicated that a significant portion of the workforce would retire in 5 to 10 years. Most highly experienced and knowledge oriented employees would become eligible for retirement. Therefore, knowledge management is presented as a complete solution in the Iranian health sector.

• Advances in environmental research
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• v.6 no.1
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• pp.67-81
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• 2017

Mining activities play a significant role in environmental pollution by producing large amounts of tailings which comprise heavy metals. The impressive increase in mining activities in recent decades, due to their high influence on the industry of developing countries, duplicates the need for a substantial effort to develop and apply efficient measures of pollution control, mitigation, and abatement. In this study, our objective was to investigate the effect of simulation of the leachate, pH and inflow intensity of transport of $Pb^{2+}$, $Zn^{2+}$, and $Cd^{2+}$ through Lakan lead and zinc plant tailings, in Iran, and to evaluate the modeling efficiency by comparing the modeling results and the results obtained from previous column studies. We used the HP1 model and the PHREEQC database to simulate metals transport through a saturated soil column during a 15 day time period. The simulations assumed local equilibrium. As expected, a lower pH and inflow intensity increased metal transport. The retardation of heavy metals followed the order $Zn^{2+}$ > $Pb^{2+}$ > $Cd^{2+}$ and the removal concentrations of Cd, Pb, and Zn at the inflow intensity critical scenario, and Cd and Pb at inflow acidity critical scenario exceeded the allowable EPA and Iranian's 1053 standard thresholds. However, although the simulation results generally agreed well with the results of the column study, improvements are expected by using multi-dimensional models and a kinetic modeling approach for the reactions involved. The results of such investigations will be highly useful for designing preventative strategies to control reactive transport of hazardous metals and minimize their environmental effects.

• Anxiety and mood
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• v.14 no.2
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• pp.80-87
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• 2018

Objective : The purpose of this study was to investigate prevalence and clinical characteristics of Post-traumatic Stress Disorder (PTSD) in North Korean defectors (NKD). Methods : The study population consisted of 300 NKDs registered in the multi-regional adaptation center (Hana Center), within three years of settling in South Korea. We conducted in-person interviews and a survey with each subject, based on the North Korean version of the WHO-Composite International Diagnostic Interview (NK-CIDI) and various clinical scales. Results : Lifetime prevalence of PTSD in NKDs was 15.3%, approximately nine times higher than South Koreans (1.7%). Although experiencing broader type of traumas with higher rate than South Koreans, NKDs revealed lower odds of PTSD in most type of trauma (p<0.05). Conclusion : NKDs are at higher risk of experiencing different types of trauma than the general population in South Korea, and it is further validated that prevalence of PTSD is also higher. Careful evaluation for comorbid psychiatric symptoms and type of traumas prior to PTSD treatment for NKDs is necessary to facilitate more appropriate intervention for each subject, according to personal experience.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.5
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• pp.897-905
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• 2007

In this paper, we present a new framework and synchronization mechanism to effectively support developing real-time communication service by using a real-time object model named TMO (Time-Triggered Message-Triggered Object). Also, we describes the application environment as the DHS(distributed high-precision simulation) to guarantee real-time service message with TMO structure in distributed network systems. The TMO scheme is aimed for enabling a great reduction of the designer's effort in guaranteeing timely real-time communication service capabilities of among distributed multi-nodes systems. Our real-time framework provide the consistent construction and configuration of tine-triggered processing components across heterogeneous distributed object environment more easily. It has been formulated from the beginning with the objective of enabling design-time guaranteeing of timely action. In the real time simulation techniques based on TMO object modeling, we have observed several advantages to the TMO structuring scheme. TMO object modeling has a strong traceability between requirement specification and design.

• Journal of Lipid and Atherosclerosis
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• v.3 no.2
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• pp.97-104
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• 2014

Objective: The aim of this study is to compare the clinical benefits between high-intensity and low-to moderate-intensity statin therapy in patients with acute myocardial infarction (AMI). Methods: A total of 1,230 patients in the Korea AMI Registry (KAMIR) were enrolled. Patients were divided into two groups according to the dosage of statin for the secondary prevention after AMI. The primary endpoint was composite of major adverse cardiac events (MACEs) including cardiac death, non-fatal MI, repeat revascularization during the 12 months of clinical follow-up. Result: The primary endpoint occurred in 101 patients (11.3%) from the low-to moderate-intensity statin group and 45 patients (13.4%) from the high-intensity statin group. The cumulative incidence of MACEs during 12-month follow-up was not significantly different between the two groups (p=0.323). After multi-variate analysis, MACEs-free survival rate was not significantly different between the two groups. Conclusion: High-intensity statin therapy did not show additional clinical benefit over low-to moderate-intensity statin therapy after AMI.

• Annals of dermatology
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• v.30 no.6
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• pp.676-687
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• 2018

Background: Rosacea is associated with chronic systemic disease. However, research is lacking in Asian countries. Objective: To evaluate the association between rosacea and cardiovascular diseases (CVDs) related systemic comorbidities, and the use of antihypertensive and antihyperlipidemic drugs in Korea. Methods: A five-year retrospective study, using hospital database, was conducted in five medical centers for five years. Totally 1,399,528 patients were evaluated. Results: The overall frequency for diagnosed rosacea was 0.18% over five years (2,536 rosacea patients). Patients with diabetes and patients with dyslipidemia were more likely to have rosacea (odd ratio [OR] 2.724, 95% confidence interval [CI] 1.295~5.730, p=0.016; OR 1.788, 95% CI 1.445~2.212, p<0.001). Patients with CVD were less likely to have rosacea (OR 0.431, 95% CI 0.244~0.760, p=0.003). Patients with ${\alpha}$-blocker prescriptions and patients with ${\beta}$-blocker prescriptions showed a tendency diagnosed with rosacea frequently (OR 1.963, 95% CI 1.200~3.212, p=0.006; OR 3.939, 95% CI 3.512~4.419, p<0.001). Patients with [beta]-hydroxy-[beta]-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, and those with fibrate, were prone to have rosacea (OR 1.599, 95% CI 1.390~1.839, p<0.001; OR 1.660, 95% CI 1.056~2.609, p=0.026). As adjusted results, among the patients who took HMG-CoA reductase inhibitor without dyslipidemia, rosacea was less likely to be diagnosed (OR 0.780, 95% CI 0.620~0.982, p=0.034). Conclusion: Rosacea is associated with chronic diseases and drugs.

• Korean Journal of Remote Sensing
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• v.16 no.1
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• pp.55-64
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• 2000

The Tropical Rainfall Measuring Mission(TRMM) Satellite was launched in November 1997, carving into orbit the first space-borne Precipitation Radar(PR). The main objective of the TRMM is to obtain and study multi-year science data sets of tropical and subtropical rainfall measurements. In the present investigation, the characteristics of heavy rainfall cases over Korea in 1998 and 1999 are analyzed using the TRMM/PR dat3. We compare the rainrate measured from TRMM/PR with the accumulated rainfall data for 10 minutes tv Automatic Weather System(AWS). Especially, horizontal cross-section of rainrate with height and longitude in the precipitating clouds are investigated. As a result of the comparison with GMS-5 IR1, the TRMM/PR data delineate well the rain type( i.e. convective, stratiform cloud and others), height of storm top and instantaneous rainrate in the precipitating clouds. The vertical structure with height and horizontal cross-section of rainrate along the longitude show the orographic effect on the rainfall. TRMM/PR instrument measures the rainrate below 6 ㎜/hr more than AWS rainguages and inclined to underestimate the rainrate than rainguages for the whole area.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.600-600
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• 2016

기후변화로 인한 가뭄 및 홍수 등의 이상 현상은 유역의 수자원에 미치는 영향이 크기 때문에 이에 대한 예측 및 적응방안을 마련하는 부분이 대두되고 있다. 따라서 본 연구에서는 유역의 수자원 관리를 위하여 단위유역에서의 수자원 취약성을 평가하고자 하였다. 평가 지표는 기후 및 사회 경제 환경적 측면을 고려하여 선정하였으며, 취약성 정의에 따라 수량 및 수질/수생태에 대하여 각각 노출, 민감도, 적응능력으로 구성하였다. 이후 다기준 의사결정기법(Multi-criteria Decision Making, MCDM) 중 TOPSIS(Technique for Order Performance by Similarity to Ideal Solution)를 적용하여 각각의 통합 취약성을 도출하였다. 지표 자료는 2010년을 기준으로 국가 통계 자료를 통해 수집하였으며, 유출량과 증발산량 자료는 준분포형 장기유출모형인 SWAT(Soil and Water Assessment Tool) 모형의 모의 자료(2005~2014)를 활용하였다. 또한, 지표에 대한 가중치는 전문가 설문조사를 통해 산정한 주관적 가중치(Subjective weight)와 수집된 자료를 통하여 산정한 객관적 가중치(Objective weight)로 구분하여 적용하였다. 인구 및 산업의 밀집도가 높은 한강권역에 대하여 표준단위유역(평균 $145km^2$)의 취약성을 평가하였으며, 각각의 취약성 우선 순위를 확인하였다. 수량 취약성의 경우에는 경기 강원북부와 충정도 일부 지역이 높은 것으로 나타났으며, 수질/수생태는 수도권 등 비교적 하류에 위치한 지역의 취약성 순위가 좀 더 높았다. 가중치 적용 방법에 따른 공간분포의 차이는 수질/수생태 취약성이 더 크게 나타나는 것을 확인할 수 있었다.