• Title/Summary/Keyword: Risk function

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A Study on the Introduction of the ETV for Disaster Prevention - Focusing on the Role of the Korea Coast Guard for the Prevention of Radioactive Waste Accidents and Marine Accidents - (재난 예방을 위한 ETV 도입에 관한 연구 - 방사성폐기물 사고 및 해양사고 예방을 위한 해양경찰의 역할을 중심으로 -)

  • Jin, Ho-hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.6
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    • pp.694-700
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    • 2018
  • Korea has disposed of medium and low level radioactive waste generated by operating nuclear power plants permanently through the radioactive waste repository located in Gyeongju. However, the maritime transport of radioactive waste is exposed to the risk of marine accidents, and it will be necessary to introduce a system to secure safety from the viewpoint of the function and role of the Korea Coast Guard. Especially, Korea is affected by large-scale marine accidents, such as the Hebei Spirit or Sewol accidents. From this point of view, we analyzed the current status of Korea radioactive waste shipping and examined the response systems of major foreign countries. As a result of examining major cases of accidents, we have operated an Emergency Towing Vessel (ETV) fleet centering on European countries in order to respond urgently to marine casualties that may have social, regional and international effects, such as accidents of similar nuclear material carriers and dangerous cargo ships. It proves a partial effect. Based on this, we propose the introduction of the Korean ETV System. In other words, it is necessary to respond to large-scale marine accidents that could lead to enormous environmental, property, and personal damage, such as marine accidents involving nuclear material ships, large oil tankers, and large passenger ships. For this, it seems necessary to introduce Korea ETV, which can carry out emergency towing, oil pollution control function, large - scale rescue equipment and manpower. This will lead to the enhancement of the Korea Coast Guard response to marine accidents, and will not miss the golden time of the initial response to the national disaster, which will help protect precious people, property and the environment.

Internal Atmosphere of Individual Sweet Persimmon Package as Function of Fruit Size and Package Film Area (과일 크기와 포장 표면적에 따른 낱개 단감 포장의 기체조성)

  • Kim, Hae-Jin;Ahn, Gwang-Hwan;Jeong, Mi-Jin;An, Duck-Soon;Lee, Dong-Sun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.16 no.2_3
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    • pp.53-58
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    • 2010
  • Internal gas composition of single unit persimmon package was evaluated at $-1^{\circ}C$ as function of package film area and fruit weight in order to find packaging conditions to achieve the optimal modified atmosphere beneficial for keeping the freshness. With large fruit size(${\approx}230\;g$), low permeable films (LLDPE/PP in 35 or $40\;{\mu}m$ thickness and $30\;{\mu}m$ OPP) with an exact fitness to the fruit (surface area of $0.040\;m^2$) resulted in anaerobic atmosphere with occurrence of browning in long term storage. With medium (${\approx}210\;g$) and medium small (${\approx}190g$) sizes, larger surface area of low permeable $35\;{\mu}m$ LLDPE/PP film provided higher $O_2$ and lower $CO_2$ concentrations causing higher occurrence of softening and blackening discoloration. On the other hand, smaller surface area of lower $O_2$ and higher $CO_2$ concentrations had a high risk of browning. Wise combination of fruit size, packaging film and surface area is required for attaining the beneficial modified atmosphere to prevent the physiological injuries.

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VRIFA: A Prediction and Nonlinear SVM Visualization Tool using LRBF kernel and Nomogram (VRIFA: LRBF 커널과 Nomogram을 이용한 예측 및 비선형 SVM 시각화도구)

  • Kim, Sung-Chul;Yu, Hwan-Jo
    • Journal of Korea Multimedia Society
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    • v.13 no.5
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    • pp.722-729
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    • 2010
  • Prediction problems are widely used in medical domains. For example, computer aided diagnosis or prognosis is a key component in a CDSS (Clinical Decision Support System). SVMs with nonlinear kernels like RBF kernels, have shown superior accuracy in prediction problems. However, they are not preferred by physicians for medical prediction problems because nonlinear SVMs are difficult to visualize, thus it is hard to provide intuitive interpretation of prediction results to physicians. Nomogram was proposed to visualize SVM classification models. However, it cannot visualize nonlinear SVM models. Localized Radial Basis Function (LRBF) was proposed which shows comparable accuracy as the RBF kernel while the LRBF kernel is easier to interpret since it can be linearly decomposed. This paper presents a new tool named VRIFA, which integrates the nomogram and LRBF kernel to provide users with an interactive visualization of nonlinear SVM models, VRIFA visualizes the internal structure of nonlinear SVM models showing the effect of each feature, the magnitude of the effect, and the change at the prediction output. VRIFA also performs nomogram-based feature selection while training a model in order to remove noise or redundant features and improve the prediction accuracy. The area under the ROC curve (AUC) can be used to evaluate the prediction result when the data set is highly imbalanced. The tool can be used by biomedical researchers for computer-aided diagnosis and risk factor analysis for diseases.

On the Requirements and Risk Management using QFD Methods for ACTD Programs (신개념기술시범(ACTD) 사업에서 QFD 기법을 이용한 요구사항 및 위험관리 방안에 관한 연구)

  • Lee, Tae-Hyung;Lee, Jae-Chon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.12B
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    • pp.1744-1751
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    • 2011
  • The concept of the advanced concept technology demonstration (ACTD) has previously been introduced in USA in order to make it possible to rapidly transfer advanced technologies developed in commercial sectors to develop weapon systems in the defense area. Since then in Korea several ACTD programs have been developed and being carried out However, there are few program management methods suitable for the characteristics of the ACTD programs, which requires stringent management of the program requirements and risks due to the radically shortened development time. In this paper such a problem has been addressed and as a solution approach the quality function deployment (QFD) method has been adopted, which is being served as a successful model in various areas such as manufacturing. The QFD method is used in our study to improve communication between various stakeholders involved in the ACTD programs and also to reduce risks related to requirements. Specifically we have developed the ACTD standard templates based on the QFD method and discussed how to use the developed templates. Finally, the application of the study result is demonstrated through the ACTD program of flight information demonstration system and also specific ways are suggested to use the standard templates, to manage requirements, and to reduce risks.

Influence of Sleep-Related Breathing Disorders on Changes of Cardiovascular Function (수면과 관련된 호흡장애가 심혈관계의 기능 변화에 미치는 영향)

  • Moon, Hwa-Sik
    • Sleep Medicine and Psychophysiology
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    • v.4 no.2
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    • pp.129-139
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    • 1997
  • The data collected to date indicate that sleep-related breathing disorders, including sleep-disordered breathing(sleep apnea) and underlying respiratory system diseases, are one of the important risk factors for cardiovascular dysfunction. Sleep-disordered breathing(sleep apnea) is now recognized as one of the leading causes of systemic hypertension, cardiac arrhythmias, coronary heart disease, pulmonary hypertension, right heart failure, and stroke. Sleep may exert a profound effect on breathing in patients with underlying respiratory system disease including bronchopumonary diseases, chest wall abnormalities, central alveolar hypoventilation syndromes or respiratory neuromuscular disorders. Chronic hypoxia and hypercapnia in these patients may accelerate the development of long term cardiovascular complications such as cardiac arrhythmias, pulmonary hypertension, and right heart failure(cor pulmonale). Several recent studies reported that sleep-related breathing disorders are associated with long-term cardiovascular morbidity and mortality. Careful assessment of respiratory and cardiovascular function in these patients is critical. Aggressive and highly effective treatment of sleep-related breathing disorders using tracheostomy, mechanical ventilation, nasal continuous positive airway pressure therapy(nCPAP), intercurrent oxygen therapy or other interventions can reduce the prevalence of cardiovascular dysfunction and the long-term mortality.

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Optimal Seismic Rehabilitation of Structures Using Probabilistic Seismic Demand Model (확률적 지진요구모델을 이용한 구조물의 최적 내진보강)

  • Park, Joo-Nam;Choi, Eun-Soo
    • Journal of the Earthquake Engineering Society of Korea
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    • v.12 no.3
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    • pp.1-10
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    • 2008
  • The seismic performance of a structure designed without consideration of seismic loading can be effectively enhanced through seismic rehabilitation. The appropriate level of rehabilitation should be determined based on the decision criteria that minimize the anticipated earthquake-related losses. To estimate the anticipated losses, seismic risk analysis should be performed considering the probabilistic characteristics of the hazard and the structural damage. This study presents the decision procedure in which the probabilistic seismic demand model is utilized for the effective estimation and minimization of the total seismic losses through seismic rehabilitation. The probability density function and the cumulative distribution function of the structural damage for a specified time period are established in a closed form, and are combined with the loss functions to derive the expected seismic loss. The procedure presented in this study could be effectively used for making decisions on the seismic rehabilitation of structural systems.

Abrogation of the Circadian Nuclear Receptor REV-ERBα Exacerbates 6-Hydroxydopamine-Induced Dopaminergic Neurodegeneration

  • Kim, Jeongah;Jang, Sangwon;Choi, Mijung;Chung, Sooyoung;Choe, Youngshik;Choe, Han Kyoung;Son, Gi Hoon;Rhee, Kunsoo;Kim, Kyungjin
    • Molecules and Cells
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    • v.41 no.8
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    • pp.742-752
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    • 2018
  • Parkinson's disease (PD) is a neurodegenerative disease characterized by progressive degeneration of dopaminergic (DAergic) neurons, particularly in the substantia nigra (SN). Although circadian dysfunction has been suggested as one of the pathophysiological risk factors for PD, the exact molecular link between the circadian clock and PD remains largely unclear. We have recently demonstrated that $REV-ERB{\alpha}$, a circadian nuclear receptor, serves as a key molecular link between the circadian and DAergic systems. It competitively cooperates with NURR1, another nuclear receptor required for the optimal development and function of DA neurons, to control DAergic gene transcription. Considering our previous findings, we hypothesize that $REV-ERB{\alpha}$ may have a role in the onset and/or progression of PD. In the present study, we therefore aimed to elucidate whether genetic abrogation of $REV-ERB{\alpha}$ affects PD-related phenotypes in a mouse model of PD produced by a unilateral injection of 6-hydroxydopamine (6-OHDA) into the dorsal striatum. $REV-ERB{\alpha}$ deficiency significantly exacerbated 6-OHDA-induced motor deficits as well as DAergic neuronal loss in the vertebral midbrain including the SN and the ventral tegmental area. The exacerbated DAergic degeneration likely involves neuroinflammation-mediated neurotoxicity. The $REV-erb{\alpha}$ knockout mice showed prolonged microglial activation in the SN along with the over-production of interleukin $1{\beta}$, a pro-inflammatory cytokine, in response to 6-OHDA. In conclusion, the present study demonstrates for the first time that genetic abrogation of $REV-ERB{\alpha}$ can increase vulnerability of DAergic neurons to neurotoxic insults, such as 6-OHDA, thereby implying that its normal function may be beneficial for maintaining DAergic neuron populations during PD progression.

A Study on the Economic Efficiency of Capital Market (자본시장(資本市場)의 경제적(經濟的) 효율성(效率性)에 관한 연구(硏究))

  • Nam, Soo-Hyun
    • The Korean Journal of Financial Management
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    • v.2 no.1
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    • pp.55-75
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    • 1986
  • This article is to analyse the economic efficiency of capital market, which plays a role of resource allocation in terms of financial claims such as stock and bond. It provides various contributions to the welfare theoretical aspects of modern capital market theory. The key feature that distinguishes the theory described here from traditional welfare theory is the presence of uncertainty. Securities has time dimensions and the state and outcome of the future are really uncertain. This problem resulting from this uncertainty can be solved by complete market, but it has a weak power to explain real stock market. Capital Market is faced with the uncertainity because it is a kind of incomplete market. Individuals and firms in capital market made their consumption-investment decision by their own criteria, i. e. the maximization of expected utility form intertemporal consumption and the maximization of the market value of firm. We noted that allocative decisions that had to be made in the economy could be naturally subdivided into two groups. One set of decisions concerned the allocation of first-period resources among consumption $C_i$, investment in risky firms $I_j$, and riskless investment M. The other decisions concern the distribution among individuals of income available in the second period $Y_i(\theta)$. Corresponing to this grouping, the theoretical analysis of efficiency has also been dichotomized. The optimality of the distribution of output in the second period is distributive efficiency" and the optimality of the allocation of first-period resources is 'the efficiency of investment'. We have found in the distributive efficiency that the conditions for attainability is the same as the conditions for market optimality. The necessary and sufficient conditions for attainability or market optimality is that (1) all utility functions are such that -$\frac{{U_i}^'(Y_i)}{{U_i}^"(Y_i)}={\mu}_i+{\lambda}Y_i$-linear risk tolerance function where the coefficients ${\mu}_i$ and $\lambda$ are independent of $Y_i$, and (2) there are homogeneous expectations, i. e. ${\Large f}_i(\theta)={\Large f}(\theta)$ for every i. On the other hand, the efficiency of investment has disagreement about optimal investment level. The investment level for market rule will not generally lead to Pareto-optimal allocation of investment. This suboptimality is caused by (1)the difference of Diamond's decomposable production function and mean-variance valuation model and (2) the selection of exelusive investment or competitive investment. In conclusion, this article has made an analysis of conditions and processes of Pareto-optimal allocation of resources in capital marker and tried to connect with significant issues in modern finance.

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Effects of herbal acupuncture(Atratylodes japonica, Coix lachrymajobi, Ephedra sinica, Atratylodes japonica mixed with Coix lachrymajobi and Ephedra sinica mixed with Green tea) at Pungnyung(ST40) and Umnungchon(SP9) in obese Rats induced by high fat diet (고지방식이(高脂肪食餌)로 유발(誘發)된 비만백서(肥滿白鼠)모델에서 창출(蒼朮), 의이인(薏苡仁), 마황(麻黃), 창출합의이인(蒼朮合薏苡仁) 마황합록차(麻黃合綠茶) 약침(藥鍼)이 혈청지질(血淸脂質) 및 간기능(肝機能)에 미치는 영향(影響))

  • Youn, Dae-Hwan;Kang, Ja-Don;Joo, Joon-Sung;Chae, Woo-Seok;Na, Chang-Su
    • Journal of Pharmacopuncture
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    • v.7 no.1 s.12
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    • pp.87-100
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    • 2004
  • Objective : This research was performed to investigate the effect of herbal acupuncture(Atratylodes japonica, Coix lachrymajobi, Ephedra sinica, Atratylodes japonica mixed with Coix lachrymajobi and Ephedra sinica mixed with Green tea) at Pungnyung(ST40) and Umnungchon(SP9) on weight gain, food intake, food efficiency, serum of lipid concentrations, liver function and HDL to total cholesterol ratio of rats fed high fat diet for 5weeks. Method : Experimental groups were divided into normal group(Normal), high fat diet group(Control), high fat diet and Atractylodes japonica-herbal acupuncture group(AJ), high fat diet and Coix lachrymajobi-herbal acupuncture group(CL), high fat diet and Ephedra sinica-herbaI acupuncture group(ES), high fat diet and Atractylodes japonica+Coix lachrymajobi-herbal acupuncture group(AJ+CL), Ephedra sinica+Green tea-herbal acupuncture group(ES+GT). Herbal acupuncture was bilaterally treated at the level of 132.5mg/kg body weight per 2day. Results : Body weight and food efficiency were decreased in AJ, ES, AJ+CL, ES+GT. The level of serum total cholesterol, triglyceride and free fatty acid were increased in AJ, ES, ES+GT. That of serum HDL-cholesterol was increased in AJ. The change of food intake, the level of serum phospholipid and ALP were not significant. The HDL to Total cholesterol ratio was increased in AJ and ES. Conclusion : Atractylodes japonica-herbal acupuncture in ST40 SP9 is effective on Body weight, food efficiency ratio, the level of serum lipid, protection of liver function and prevention cardiovascular risk by obesity induced by high fat diet. Herbal acupuncture mixed Ephedra sinica with Green tea can control the body weight, food efficiency ratio and the level of serum lipid.

Changes of Renal Function and Treatment after CABG in Patients with Elevated Serum Creatinine (크레아티닌치가 높은 환자에서 관상동맥우회술 후 신장기능의 변화와 처치)

  • Choi Jong Bum;Lee Mi Kyuong;Lee Sam Youn
    • Journal of Chest Surgery
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    • v.38 no.2 s.247
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    • pp.146-151
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    • 2005
  • Background: Preoperative elevated serum creatinine values are associated with increased risk for both morbidity and mortality in patients undergoing on-pump coronary artery bypass surgery (CABG). We investigated the postoperative changes of renal function and proper management in the patients. Material and Method: Among 74 consecutive patients who underwent isolated on-pump CABG, 17 patients with increased serum creatinine level $(creatinine\;\geqq\;1.5\;mg/dL)$ within preoperative one week wereincluded in the study. Seven patients showed pre­operative serum creatinine level of 2.0 mg/dL or higher, and 3 of them had been undergoing hemodialysis. Preoperative hemodialysis was performed in the 3 patients due to end-stage renal failure (ESRD) the day before the operation. We started peritoneal dialysis immediately after the cardiopulmonary bypass in patients with ESRD or postoperative acute renal failure if it was necessary to remove intravascular volume and lower serum creatinine level. Result In most of the patients with CABG, postoperative serum creatinine level increased and recovered to the preoperative level at the discharge. In 2 of the 4 patients with serum creatinine level of 2.0 mg/dL or higher and 3 patients with ESRD, intravascular volume, serum creatinine level and serum electrolyte were controlled with peritoneal dialysis. Conclusion: Postoperative serum creatinine level increased transiently in most of CABG patients, and intravascular volume and serum creatinine level were controlled by peritoneal dialysis only in the patients with acute renal failure postoperatively and those depending on hemodialysis.