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The Prediction of Currency Crises through Artificial Neural Network (인공신경망을 이용한 경제 위기 예측)

  • Lee, Hyoung Yong;Park, Jung Min
    • Journal of Intelligence and Information Systems
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    • v.22 no.4
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    • pp.19-43
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    • 2016
  • This study examines the causes of the Asian exchange rate crisis and compares it to the European Monetary System crisis. In 1997, emerging countries in Asia experienced financial crises. Previously in 1992, currencies in the European Monetary System had undergone the same experience. This was followed by Mexico in 1994. The objective of this paper lies in the generation of useful insights from these crises. This research presents a comparison of South Korea, United Kingdom and Mexico, and then compares three different models for prediction. Previous studies of economic crisis focused largely on the manual construction of causal models using linear techniques. However, the weakness of such models stems from the prevalence of nonlinear factors in reality. This paper uses a structural equation model to analyze the causes, followed by a neural network model to circumvent the linear model's weaknesses. The models are examined in the context of predicting exchange rates In this paper, data were quarterly ones, and Consumer Price Index, Gross Domestic Product, Interest Rate, Stock Index, Current Account, Foreign Reserves were independent variables for the prediction. However, time periods of each country's data are different. Lisrel is an emerging method and as such requires a fresh approach to financial crisis prediction model design, along with the flexibility to accommodate unexpected change. This paper indicates the neural network model has the greater prediction performance in Korea, Mexico, and United Kingdom. However, in Korea, the multiple regression shows the better performance. In Mexico, the multiple regression is almost indifferent to the Lisrel. Although Lisrel doesn't show the significant performance, the refined model is expected to show the better result. The structural model in this paper should contain the psychological factor and other invisible areas in the future work. The reason of the low hit ratio is that the alternative model in this paper uses only the financial market data. Thus, we cannot consider the other important part. Korea's hit ratio is lower than that of United Kingdom. So, there must be the other construct that affects the financial market. So does Mexico. However, the United Kingdom's financial market is more influenced and explained by the financial factors than Korea and Mexico.

The usefulness of diagnostic tests in children with language delay (언어 발달지연 환아에서 진단적 검사의 유용성)

  • Oh, Seung Taek;Lee, Eun Sil;Moon, Han Ku
    • Clinical and Experimental Pediatrics
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    • v.52 no.3
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    • pp.289-294
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    • 2009
  • Purpose : To assess the usefulness of magnetic resonance imaging (MRI), karyotyping, brainstem auditory evoked potential (BAEP), electroencephalogram (EEG), tandem mass screening test, and newborn metabolic screening test in children with language delay for diagnosing underlying diseases. Methods : From January 2000 to June 2007, a retrospective chart review was performed for 122 children with language delay who visited the Child Neurology Clinic at Yeungnam University Hospital and who underwent neuropsychologic tests and other diagnostic evaluations for underlying diseases. They were grouped into phenomenological diagnostic categories, and test results were analyzed according to the underlying diseases. Results : Of 122 patients, 47 (38.5%) had mental retardation, 40 (32.8%) had developmental language disorders, 23 (18.9 %) had borderline IQ, and 12 (9.8%) had autism spectrum disorder. In 26 (21.3%) cases, the causes or relevant clinical findings to explain language delay were found. Eight (10.4%) of 77 MRIs, 6 (8.0%) of 75 EEGs, and 4 (5%) of 80 BAEPs showed abnormal results. Results directly attributed to diagnosing underlying diseases were 2 hearing defects in BAEPs and 1 bilateral perisylvian cortical dysplasia in MRIs. No abnormal results were found in karyotyping, tandem mass screening tests, and new-born screening tests. Conclusion : Commonly used tests to diagnose the cause of language delay are not very effective and should only be used selectively, according to patient characteristics. However, despite the low diagnostic yields from these tests, because many patients show abnormal results, these tests are useful when conducted in complete evaluation.

A Methodology for Predicting Overall Tank Dimension (전차 Dimension 예측에 관한 방법론)

  • Yang, Dong-Soon
    • Journal of the military operations research society of Korea
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    • v.4 no.1
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    • pp.80-90
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    • 1978
  • 전차의 Dimension은 다음과 같은 전차의 기능에 영향을 미친다. 즉 Firepower, Mobility, Armorthickness and Target detection Instrument등, 이들은 서로 상관성을 가지고 있다. 승무원(crew)을 보호한다고 하며 지나치게 장갑(thickness)에 중점을 두면 전차의 속도가 감소되여 적의 대전차포에 취약해지며 기습적인 기동력을 발휘하지 못한바. 반면에 공격적인 기동력을 중요시하며 속도에 치중한다면 Engine의 크기가 커지며 그 원인은 전차의 크기를 더하여 좋은 Target의 대상이 된다. 여기에서 한가지 예를 들었지만 이러한 상관관계는 많이 존재하며 이러한 약점을 제거하고서도 좋은 전차를 설계하는 것이 목적이다. 좋은 Horse Power를 내면서도 재래식 Engine 보다 Engine의 크기를 작게하는 방법은 없을까? 하는 점을 여기서 엿볼 수 있다. 시간과 예산을 절약하려면 생산전에 충분한 Disign과 연구가 필요함을 강조하고 있다.

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Effects of Substrate-Grounding and the Sputtering Current on $YBa_2Cu_3O_{7-y}$ Thin-Film Growth by Sputtering in High Gas Pressures (고압 스터터링 방법으로 $YBa_2Cu_3O_{7-y}$박막을 제조할 때 기판의 접지 여부와 인가전류의 양이 박막 성장에 미치는 영향)

  • 한재원;조광행;최무용
    • Journal of the Korean Vacuum Society
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    • v.4 no.1
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    • pp.40-45
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    • 1995
  • 직경 2인치의 YBa2Cu3O7-y 타겟을 사용하여 높은 스퍼터링 기체 압력 하에서 off-axis DC-마그네트론 스퍼터링 방법으로 MgO(100) 단결정 기판 위에 YBa2Cu3O7-y 박막을 c축 방향으로 in-냐셔 성장시킬 때 기판의 접지 여부와 인가전류의 양이 박막 성장에 미치는 여향을 연구하였다. 그 결과 접지 여부는 박막의 초전도 변환온도, 전기수송 특성, 결정 구조적 특성에는 영향을 거의 주지 않는 반면 표면상태에는 상당한 영향을 미치며, 인가전류의 양은 초전도 특성에 많은 영향을 미침을 발견하였다. 기판온도 $670^{\circ}C$, 스퍼터링 기체압력 300mTorr, 아르곤 대 산소 분압비 5:1의 조건에서 인가전류의 최적량은 300-500 mA이었으며 평균 박막 성장속도는 $0.11-0.14AA$/s로 매우 낮았다. 기판의 접지 효과와 낮은 성장속도의 원인에 대해 고찰해 본다.

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A Meta-Analysis of Recent Korean Studies on Consumer Trust in Internet Shopping Mall (인터넷 쇼핑몰 고객의 신뢰 형성에 관한 최근 국내연구의 메타 분석적 고찰)

  • Min Dong-Kwon
    • Journal of Korea Society of Industrial Information Systems
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    • v.10 no.4
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    • pp.97-109
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    • 2005
  • Through a meta-analytic methodology, this research analyzes and integrates recently published studies in Korea on customer trust in Internet shopping malls. To this end, the trend in the relevant research area is surveyed, and the meta-analytic procedures are applied accordingly. As results of statistical tests, most preceding and following variables of trust are found significant from the integrative point of view. In addition, a necessity for more reliable empirical studies in the area is identified.

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A Study on the Interpolation of Missing Rainfall : 1. Methodologies and Weighting Factors (결측 강우량 보정방법에 관한 연구: 1. 방법론 및 가중치 산정)

  • Kim Eung-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.4
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    • pp.684-689
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    • 2006
  • Rainfall is the most basic input data to analyze the hydrologic system. When we measure the rainfall data, the rainfall data can be missing due to various reasons. Therefore, various interpolation methods are available for compensating the missing data. However, the interpolation methods were used without considering their applicability and accuracy. This study compares the interpolation methods such as the arithmetic mean method, normal ratio method, modified normal ratio method, inverse distance method, linear programming, Kriging method to estimate the existing rainfall correction method.

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A case study on the diagnostic framework in order to verify and solve a system issue (시스템 이슈 식별과 해결을 위한 진단 Framework 구축 사례 연구)

  • Shin, Hyun-Jong;Park, Dong-Hyun
    • 한국IT서비스학회:학술대회논문집
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    • 2009.05a
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    • pp.247-250
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    • 2009
  • 본 연구는 SI 프로젝트 현장에서 시스템의 주요 이슈를 최소화하기 위한 진단 Framework를 구축하는 방안에 대해 고찰한 것이다. SI 프로젝트에서 심각한 Risk로 발전할 가능성이 있는 시스템 이슈들을 효과적으로 관리하기 위해서는, 사전에 (1) 시스템 이슈 점검을 위한 조직에서 이슈 식별을 위한 방법과 절차를 확립해야 하고, (2) 프로젝트 수행 조직의 구성원이 담당 업무 별로 이슈 식별을 할 수 있도록 역할을 설정해야 한다. 더불어 (3) 식별된 이슈들은 올바른 절차에 따라 시정 조치가 취해져야 하고, (4) 시정 조치가 합당한지에 대한 영향 분석 및 평가를 거쳐 시스템 오픈 여부를 결정할 수 있어야 한다. 뿐만 아니라 (5) 유사한 SI 프로젝트에서 발생 가능한 시스템 이슈들은 발생 원인과 해결 방법이 정리되어 시행착오를 줄일 수 있도록 진단 방법론이 지속적으로 보강되어야 한다.

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A Study for Evaluation Method on Defense Information System (국방정보화 평가방안에 관한 연구)

  • Choi, Heon-Jun
    • 한국IT서비스학회:학술대회논문집
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    • 2003.05a
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    • pp.376-381
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    • 2003
  • 최근 국방정보화 투자 규모가 늘어남에 따라 정보화 평가에 대한 관심이 높아지고 있다. 특히 자원관리 분야와 C4I에 대한 투자가 확산됨과 동시에 정보기술의 다양성과 복잡도가 증가함에 따라 조직의 정보화 수준과 성과에 대한 평가 필요성이 확산되고 있다. 이러한 현상은 급속하게 변화된 정보기술 패러다임과 높아지는 정보화 실패율에서도 그 원인을 찾을 수 있다. 이러한 정보기술의 성과가 복합적, 간접적, 장기적, 무형적 형태로 나타나므로 그 평가가 더욱 어려워지고 있다. 본 연구에서는 현재 진행 중인 국방정보화의 추진 동향을 살펴보고, 국내 정보화평가방법론에 관하여 살펴보았다. 그리고 국방부에서 추진해야 할 국방정보화 평가의 방안을 제시하였다.

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An Experience of Therapeutic Plasma Exchange in 9 Pediatric Patients (소아에서 시행한 치료적 혈장교환술 9례의 임상적 고찰)

  • Lee Jee-Hyun;Jeon Ga-Won;Park Sung-Eun;Jin Dong-Kyu;Paik Kyung-Hoon
    • Childhood Kidney Diseases
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    • v.9 no.1
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    • pp.38-45
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    • 2005
  • Purpose : The purpose of this study was to analyze the therapeutic effect of plasmapheresis in various pediatric diseases. Methods : Therapeutic plasmapheresis was performed by COBE Spectra centrifugation. Nine cases were included in this study. The number an[;. method of plasmapheresis, together with the progress and prognosis of each case were retrospectively reviewed. Results : The patients' ages ranged from 26 mont]Is to 16 years of age, and the mean age was 9.9 years. There were S males and 4 females. The underlying diseases requiring plasmapheresis included 2 cases of hemolytic uremic svndrome(HUS), 1 case of lupus nephritis, 2 cases of rapidly Progressive glomerulonephritis(RPGN), 1 case of focal segmental glomorulosclerosis(FSGS), 1 case of systemic vasculitis after pulmonary hemorrhage, 1 case of acute renal failure associated with pulmonary hemoIThage, and 1 case of acute rejection after renal transplantation. The average number of plasmapheresis performed was 6.2 times with a range of 3 to 13 times. The patients with HUS, lupus nephritis, ANCA positive systemic vasculitis induced by pulmonary hemorrhage and ARF-associated pulmonary hemorrhage showed a good response to therapeutic plasmapheresis, but the patients with RPGN, refractory FSGS, and acute rejection after renal transplantation were not responsive to treatment. The most common side effect was hypocalcemia which was rarely symptomatic. Vital signs were not compromised. Conclusion : Although it is presumptuous to generalize the therapeutic effects of plasma pheresis in different diseases due to the small number of study subjects, this study shows that plasmapheresis may be an effective therapeutic modality in various pediatrics diseases and should be considered as a therapeutic option.

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Evaluation of the Underlying Etiology and Long-Term Prognostic Factors in Neonatal Cholestasis (신생아 담즙정체증의 원인질환 및 장기추적 예후인자에 관한 고찰)

  • Kim, Kyung-Mo;Seo, Jeong-Kee
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.2 no.1
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    • pp.46-58
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    • 1999
  • Purpose: The aim of the present study was to evaluate the long-term clinical profile including the underlying etioligy and the prognostic factors of the neonatal cholestasis. Method: We studied the 190 infants presented with neonatal cholestasis for the last 12 years (from 1981 to 1992). The underlying causes, clinical findings and long-term outcomes were evaluated. And the prognostic factors were also analyzed. Result: Underlying disease were neonatal hepatitis in 101 (idiopathic in 77 and infectious in 24), intrahepatic bile duct paucity in 5, biliary atresia in 79, choledochal cyst in 5. Metabolic disease was not observed in this study. The important clinical problems during follow-up were persistent high fever, gastrointestinal bleeding, hepatic encephalopathy and ascites. The main causes of the death were hepatic encephalopathy and gastrointestinal bleeding. While three fourth of infants with idiopathic and infectious neonatal hepatitis recovered usually within a year, five-year survival rate for biliary atresia was just 40%, the mortality observed usually within the first year after Kasai operation and prognostic factor was the time of operation. Underlying disease was the most important prognostic factor of neonatal cholestasis. Conclusion: This study showed that most common causes of neonatal cholestasis were biliary atresia and idiopathic neonatal hepatitis, infectious neonatal hepatitis, choledochal cyst and Alagille syndrome, but few neonatal cholestasis of genetic or metabolic liver disease was observed. The most important long-term prognostic factor of neonatal cholestasis was the underlying disease.

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