• Title/Summary/Keyword: sigmoid

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신경망기법을 이용한 기업부실예측에 관한 연구

  • Jeong, Gi-Ung;Hong, Gwan-Su
    • The Korean Journal of Financial Management
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    • v.12 no.2
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    • pp.1-23
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    • 1995
  • 본 연구의 목적은 특정 금융기관의 주거래기업들에 대한 부실예측을 위해 주거래기업들을 잠식, 도산, 그리고 건전기업과 같이 세집단으로 구분하여 예측하고자 하며, 기업부실 예측력에 영향을 미치는 세 가지 요인으로서 표본구성, 투입 변수, 분석 기법의 관점에서 다음을 살펴보는 것이다. 첫째, 기업부실예측에서 전통적인 delta learning rule과 sigmoid함수를 사용한 역전파학습(신경망 I)과 이들의 변형형태인 normalized cumulative delta learning rule과 hyperbolic tangent함수를 사용한 역전파 학습(신경망 II)과의 예측력의 차이를 살펴보고 또한 이러한 두가지 신경망기법의 예측력을 MDA(다변량판별분석) 결과와 비교하여 신경망기법에 대한 예측력의 유용성을 살펴보고자 한다. 둘째, 세집단분류문제에서는 잠식, 도산, 건전기업의 구성비율이 위의 세가지 예측기법의 결과에 어떠한 영향을 미치는지를 살펴보고자 한다. 세째, 투입 변수선정은 기존연구 또는 이론을 바탕으로 연구자의 판단에 의해 선택하는 방법과 다수의 변수를 가지고 통계적기법에 의해 좋은 판별변수의 집합을 찾는 것이다. 본 연구에서는 이러한 방법들에 의해 선정된 투입변수들이 세가지 예측기법의 결과에 어떠한 영향을 미치는지를 살펴보고자 한다. 이러한 관점에서 본 연구의 실증분석 결과를 요약하면 다음과 같다. 1) 신경망기법이 두집단에서와 같이 세집단 분류문제에서도 MDA보다는 더 높은 예측력을 보였다. 2) 잠식과 도산기업의 수는 비슷하게 그리고 건전기업의 수는 잠식과 도산기업을 합한 수와 비슷하게 표본을 구성하는 것이 예측력을 향상하는데 도움이 된다고 할 수 있다. 3) 속성별로 고르게 투입변수로 선정한 경우가 그렇지 않은 경우보다 더 높은 예측력을 보였다. 4) 전통적인 delta learning rule과 sigmoid함수를 사용한 역전파학습 보다는 normalized cumulative delta learning rule과 hyperbolic tangent함수를 사용한 역전파 학습이 더 높은 예측력을 보였다. 이러한 현상은 두집단문제에서 보다 세집단문제에서 더 큰 차이를 나타내고 있다.

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A Case of Mucinous Adenocarcinoma of the Sigmoid Colon in a Child (소아의 결장에서 발생한 원발성 선암종 1예)

  • Jung, Jae-Youl;Seo, Yu-Koyng;Kim, Ae-Suk;Lee, Sun-Ju;Cho, Sung-Min;Lee, Dong-Seok;Kim, Doo-Kwun;Choi, Sung-Min;Kim, Dong-Hoon
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.10 no.1
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    • pp.81-85
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    • 2007
  • Colorectal carcinomas occur primarily in elderly people and are rare in children. Unlike adult colorectal carcinomas, the overall prognosis is very poor because of the usual delay in diagnosis and advanced stages at presentation or initial diagnosis, and a high incidence of aggressive tumor pathology such as mucinous adenocarcinoma. Colon cancer should not be excluded in children only based on age or barium enema results. Therefore, colonoscopy should be performed in pediatric patients with unexplained rectal bleeding and abdominal pain. We report a rare case of a child with a mucinous adenocarcinoma of the sigmoid colon in a 12-year-old boy, who presented with an abdominal mass and abdominal pain and review the medical literature.

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A Study on the Storage of Fresh Fruits and Vegetables(III) -Effects of the Storage of Tomato fruits by controlled atmospheric pressure- (청과물 저장에 관한 연구(제3보) -환경압력변화가 Tomato 과실의 저장에 미치는 영향에 대하여-)

  • Kim, Sung-Dal;Choi, Jong-Uck;Sohn, Tae-Hwa
    • Applied Biological Chemistry
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    • v.16 no.2
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    • pp.94-98
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    • 1973
  • 1. Tomato variety used was Bogsu No. 2 and it was grown in field. Experiments were conducted in 1971 and 1972 to examine the changes of $CO_2$ product on in each growth-period and the contents of acid, sugar and vitamine C during storage. 2. By controlled atmospheric pressure the effects of respirationreduction in tomato fruits were the most effective at 660 Torr. part. 3. $CO_2$ production of tomato fruits harvested at each growth-period was differently changed at each growth-period and $CO_2$ production in tomato fruit at the same maturity from the plant showed Sigmoid type. 4. $CO_2$ production of tomato fruits harvested at the same ripeness score was in influenced by controlled atmospheric pressure during growth period and $CO_2$ production was reduced at SAP part compared with NAP part during the full growth-period. 5. The change of weight in tomato fruits was decreased in NAP part than in SAP part during storage and contents of acid, sugar, and vitamine C showed the same tendency.

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Adsorption Characteristics and Moisture Content Prediction Model of Coffee with Water Activity and Temperature (수분활성과 온도변화에 따른 커피의 흡착특성 및 흡착량 예측모델)

  • Youn, Kwang-Seop;Choi, Yong-Hee
    • Korean Journal of Food Science and Technology
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    • v.22 no.6
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    • pp.690-695
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    • 1990
  • The adsorption characteristics of coffee were mvestigated at $5, 15, 25, and 35^{\circ}C$ under various water activities such as 11, 32, 57, 75 and 90% and prediction models were developed by optimization program. The moisture adsorption isotherm curves were similar to the typical sigmoid type. The values of equilibrium moisture content and the monolayer moisture content were highest in the Freeze Dried, which was due to porous structure by the drying method. In the result of adjusting the isotherm models in this paper, Halsey model generally gave the best fit for isotherms of coffee. Prediction model for equilibrium moisture content was established with water activity and temperature. Adsorption prediction models were also developed with water activity, with water activity and time, and with water activity, time and temperature, respectively.

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Stomal Complications in Children (소아 장루의 합병증)

  • Park, Joong-Jai;Lee, Joo-Hong;Jung, Jong-Do;Choi, Young-Cheol;Chung, Woo-Shik;Jun, Si-Youl
    • Advances in pediatric surgery
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    • v.8 no.1
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    • pp.11-15
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    • 2002
  • This is a 20 year analysis of the problems associated with enterostomy formation, and closure. Forty-three stomas were established in 43 patients: 23 for anorectal malformations, 11 for Hirschsprung's diseases, 4 for necrotizing enterocolitis, 3 for multiple ileal atresias, 1 for volvulus neonatorum with perforation, and 1 for diaphragmatic hernia with colon perforation. Thirty boys and 13 girls were included (mean age 4.8 months). Stoma complications were encountered in 13 patients (30.2 %): stomal prolapse, stenosis, obstruction, paracolic hernia, retraction, dysfunction, and skin excoriation, Four patients (9.3 %) required stomal revision. Occurrence of complications was not related to age and primary disease, but sigmoid colostomy showed lower complication rate than transverse colostomy (20.0 % vs 42.9 %, p<0.05). There were five deaths but, only one (2.3 %) was directly related to the enterostomy complication. Twenty-one stomas were closed in our hospital and complications occurred in seven patients (33.3 %). The most common complication was wound sepsis in 5 children. In conclusion, because the significant morbidity of stomal formation still exists, refinements of the surgical technique seem to be required, Sigmoid loop colostomy is preferred whenever possible.

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Design and Implementation of the Digital Neuron Processor for the real time object recognition in the making Automatic system (생산자동화 시스템에서 실시간 물체인식을 위한 디지털 뉴런프로세서의 설계 및 구현)

  • Hong, Bong-Wha;Joo, Hae-Jong
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.3
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    • pp.37-50
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    • 2007
  • In this paper, we designed and implementation of the high speed neuron processor for real time object recognition in the making automatic system. and we designed of the PE(Processing Element) used residue number system without carry propagation for the high speed operation. Consisting of MAC(Multiplication and Accumulation) operator using residue number system and sigmoid function operator unit using MAC(Mixed Radix conversion) is designed. The designed circuits are descript by C language and VHDL(Very High Speed Integrated Circuit Hardware Description Language) and synthesized by compass tools and finally, the designed processor is fabricated in $0.8{\mu}m$ CMOS process. we designed of MAC operation unit and sigmoid proceeding unit are proved that it could run time 0.6nsec on the simulation and improved to the speed of the three times and decreased to hardware size about 50%, each order. The designed neuron processor can be implemented of the object recognition in making automatic system with desired real time processing.

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The Performance Improvement of Backpropagation Algorithm using the Gain Variable of Activation Function (활성화 함수의 이득 가변화를 이용한 역전파 알고리즘의 성능개선)

  • Chung, Sung-Boo;Lee, Hyun-Kwan;Eom, Ki-Hwan
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.38 no.6
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    • pp.26-37
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    • 2001
  • In order to improve the several problems of the general backpropagation, we propose a method using a fuzzy logic system for automatic tuning of the activation function gain in the backpropagation. First, we researched that the changing of the gain of sigmoid function is equivalent to changing the learning rate, the weights, and the biases. The inputs of the fuzzy logic system were the sensitivity of error respect to the last layer and the mean sensitivity of error respect to the hidden layer, and the output was the gain of the sigmoid function. In order to verify the effectiveness of the proposed method, we performed simulations on the parity problem, function approximation, and pattern recognition. The results show that the proposed method has considerably improved the performance compared to the general backpropagation.

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Development of New Collaborative Key Performance Indicators in Manufacturing Collaboration Based on the SCOR Model (SCOR 모형에 기반한 새로운 제조협업의 협력적 성과지표 개발 및 측정)

  • Jung, Ji-Whan;Jung, Jae-Yoon;Shin, Dong-Min;Kim, Sang-Kuk
    • The Journal of Society for e-Business Studies
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    • v.15 no.1
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    • pp.157-171
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    • 2010
  • To effectively maintain manufacturing collaboration, the development of effective performance measurements for the collaboration is required. Most existing key performance indicators however were developed to measure the performances of internal activities or outsourcing of a company. For that reason, it is necessary to devise new key performance indicators that the partners participating in the collaboration can arrange and compromise with each other to reflect their common goals. In this paper, we propose collaborative Key Performance Indicators(cKPIs), which is used to measure the collaboration work of multiple manufacturing partners on the basis of the Supply Chain Operations Reference(SCOR) model. Also, a modified Sigmoid function is devised as a desirability function to reflect the characteristics of Service Level Agreement(SLA) between two partners. The proposed indicators and the desirability functions can be utilized to perform and maintain the successful collaboration by providing a way to the quantitative measurement.

Absorption Characteristics and Prediction Model of Ginger Powder by Different Drying Methods (건조방법에 따른 생강분말의 흡습특성과 예측모델에 관한 연구)

  • Shin, Hae-Kyoung;Hwang, Sung-Hee;Youn, Kwang-Sup
    • Korean Journal of Food Science and Technology
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    • v.35 no.2
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    • pp.211-216
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    • 2003
  • Absorption characteristics of hot air-. vacuum-, and freeze-dried ginger powder were investigated. Monolayer moisture content as determined by GAB equation was $0.257{\sim}0.540\;H_2O/g$, showing higher significance than BET equation. Absorption enthalpy was calculated based on different drying methods and water activities. Absorption energy decreased with increasing water activity but was not affected by drying method. Isotherm curves showed a typical sigmoid form. Among models applied for predicting equilibrium moisture content, Caurie model was the best fit model for ginger powder, showing the lowest prediction deviation of $1.2{\sim}5.4%$, followed by Henderson then Bradley models. The prediction model equations for the moisture content were established by in(time), water activity, and temperature.

Rule-based Hybrid Discretization of Discrete Particle Swarm Optimization for Optimal PV System Allocation (PV 시스템의 최적 배치 문제를 위한 이산 PSO에서의 규칙 기반 하이브리드 이산화)

  • Song, Hwa-Chang;Ko, Jae-Hwan;Choi, Byoung-Wook
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.6
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    • pp.792-797
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    • 2011
  • This paper discusses the application of a hybrid discretiziation method for the discretization procedure that needs to be included in discrete particle swarm optimization (DPSO) for the problem of allocating PV (photovoltaic) systems onto distribution power systems. For this purpose, this paper proposes a rule-based expert system considering the objective function value and its optimizing speed as the input parameters and applied it to the PV allocation problem including discrete decision variables. For multi-level discretization, this paper adopts a hybrid method combined with a simple rounding and sigmoid funtion based 3-step and 5-step quantization methods, and the application of the rule based expert system proposing the adequate discretization method at each PSO iteration so that the DPSO with the hybrid discretization can provide better performance than the previous DPSO.