• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.53-58
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• 2008

Purpose: To design and fabricate the small sputter coating system for the Ophthalmic lens. Methods: The design of sputter target was done using macleod program for AR coating and mirror coating of Ophthalmic lens with Si target and then the sputter system was fabricated. Results: The optimum condition of AR coating with Si target was [air|$SiO_2$(81.3)|$Si_3N_4$ (102)|$SiO_2$(19.21)|$Si_3N_4$(15.95)|$SiO_2$(102)|glass], for blue color mirror coating [air|$SiO_2$(56.61)|$Si_3N_4$(135.86)|$SiO_2$(67.64)|$Si_3N_4$(55.4)|$SiO_2$(53.53)|$Si_3N_4$(51.28)|glass], for green color coating [air|$SiO_2$(66.2)|$Si_3N_4$(22.76)|$SiO_2$(56.58)|$Si_3N_4$(140.35)|$SiO_2$(152.35)|$Si_3N_4$(70.16)|$SiO_2$(121.87)|glass], for gold color [air|$SiO_2$(83.59)|$Si_3N_4$(144.86)|$SiO_2$(11.82)|$Si_3N_4$(129.93)|$SiO_2$(90.01)|$Si_3N_4$(88.37)|glass]. Conclusions: In the fabrication of sputtering coating apparatus, Dual cathode with same Ti target were coated at the same time on both sides of Ophthalmic lens to lessen the time of coating on Ophthalmic Lens and save the cost of the lens. The distance of target-substrate of cathode was variable from 12.5 cm to 20 cm. Turbo pump was used to take the whole coating process about 15 min. instead of diffusion pump. The lens holder was made to coat 2 pairs lens every coating and was rotated to get the uniformity of thin film.

• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.23-45
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• 2020

Big data is creating in a wide variety of fields such as medical care, manufacturing, logistics, sales site, SNS, and the dataset characteristics are also diverse. In order to secure the competitiveness of companies, it is necessary to improve decision-making capacity using a classification algorithm. However, most of them do not have sufficient knowledge on what kind of classification algorithm is appropriate for a specific problem area. In other words, determining which classification algorithm is appropriate depending on the characteristics of the dataset was has been a task that required expertise and effort. This is because the relationship between the characteristics of datasets (called meta-features) and the performance of classification algorithms has not been fully understood. Moreover, there has been little research on meta-features reflecting the characteristics of multi-class. Therefore, the purpose of this study is to empirically analyze whether meta-features of multi-class datasets have a significant effect on the performance of classification algorithms. In this study, meta-features of multi-class datasets were identified into two factors, (the data structure and the data complexity,) and seven representative meta-features were selected. Among those, we included the Herfindahl-Hirschman Index (HHI), originally a market concentration measurement index, in the meta-features to replace IR(Imbalanced Ratio). Also, we developed a new index called Reverse ReLU Silhouette Score into the meta-feature set. Among the UCI Machine Learning Repository data, six representative datasets (Balance Scale, PageBlocks, Car Evaluation, User Knowledge-Modeling, Wine Quality(red), Contraceptive Method Choice) were selected. The class of each dataset was classified by using the classification algorithms (KNN, Logistic Regression, Nave Bayes, Random Forest, and SVM) selected in the study. For each dataset, we applied 10-fold cross validation method. 10% to 100% oversampling method is applied for each fold and meta-features of the dataset is measured. The meta-features selected are HHI, Number of Classes, Number of Features, Entropy, Reverse ReLU Silhouette Score, Nonlinearity of Linear Classifier, Hub Score. F1-score was selected as the dependent variable. As a result, the results of this study showed that the six meta-features including Reverse ReLU Silhouette Score and HHI proposed in this study have a significant effect on the classification performance. (1) The meta-features HHI proposed in this study was significant in the classification performance. (2) The number of variables has a significant effect on the classification performance, unlike the number of classes, but it has a positive effect. (3) The number of classes has a negative effect on the performance of classification. (4) Entropy has a significant effect on the performance of classification. (5) The Reverse ReLU Silhouette Score also significantly affects the classification performance at a significant level of 0.01. (6) The nonlinearity of linear classifiers has a significant negative effect on classification performance. In addition, the results of the analysis by the classification algorithms were also consistent. In the regression analysis by classification algorithm, Naïve Bayes algorithm does not have a significant effect on the number of variables unlike other classification algorithms. This study has two theoretical contributions: (1) two new meta-features (HHI, Reverse ReLU Silhouette score) was proved to be significant. (2) The effects of data characteristics on the performance of classification were investigated using meta-features. The practical contribution points (1) can be utilized in the development of classification algorithm recommendation system according to the characteristics of datasets. (2) Many data scientists are often testing by adjusting the parameters of the algorithm to find the optimal algorithm for the situation because the characteristics of the data are different. In this process, excessive waste of resources occurs due to hardware, cost, time, and manpower. This study is expected to be useful for machine learning, data mining researchers, practitioners, and machine learning-based system developers. The composition of this study consists of introduction, related research, research model, experiment, conclusion and discussion.

• KIPS Transactions on Software and Data Engineering
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• v.7 no.9
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• pp.351-360
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• 2018

The LWR (Locally Weighted Regression) model, which is traditionally a lazy learning model, is designed to obtain the solution of the prediction according to the input variable, the query point, and it is a kind of the regression equation in the short interval obtained as a result of the learning that gives a higher weight value closer to the query point. We study on an incremental ensemble learning approach for LWR, a form of lazy learning and memory-based learning. The proposed incremental ensemble learning method of LWR is to sequentially generate and integrate LWR models over time using a genetic algorithm to obtain a solution of a specific query point. The weaknesses of existing LWR models are that multiple LWR models can be generated based on the indicator function and data sample selection, and the quality of the predictions can also vary depending on this model. However, no research has been conducted to solve the problem of selection or combination of multiple LWR models. In this study, after generating the initial LWR model according to the indicator function and the sample data set, we iterate evolution learning process to obtain the proper indicator function and assess the LWR models applied to the other sample data sets to overcome the data set bias. We adopt Eager learning method to generate and store LWR model gradually when data is generated for all sections. In order to obtain a prediction solution at a specific point in time, an LWR model is generated based on newly generated data within a predetermined interval and then combined with existing LWR models in a section using a genetic algorithm. The proposed method shows better results than the method of selecting multiple LWR models using the simple average method. The results of this study are compared with the predicted results using multiple regression analysis by applying the real data such as the amount of traffic per hour in a specific area and hourly sales of a resting place of the highway, etc.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.340-347
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• 2001

Seasonal variation of the elemental and biochemical composition of the suspended particulate matter (SPM) was investigated in terms of quantity and quality of diets for suspension feeders from July 1999 to August 2000 in two coastal bay systems of Gosung and Kangjin Bays in Korea. No clear patterns in the seasonal variations of SPM concentration were found in these two bay systems. The results indicated that the seasonal variation of SPM could not be considered the variation of food available to suspension-feeders. The simultaneous peaks in chlorophyll a and biochemical components in summer indicated that the quantity of the particulate organic matter primarily depended on phytoplankton productivity. However, no correlation between chlorophyll a and biochemical components [particulate protein (PPr), carbohydrate (PCHO) and lipid] were found, indicating that other processes might also contribute to the particulate organic matter in the period when the phytoplankton biomass was low. High C: Chl a and C:N, and carbohydrate peaks during the autumn to spring period suggested that resuspension of surface sediments was a probable process to supply the particulate organic matter. The food material, represented by summing up the total quantity of three biochemical components, was highest in spring with minor peaks during the period from autumn to the next spring, The food index, calculated as the ratio of food material to total SPM, did not generally exceed $6\%$ with short peaks during the year. Therefore, nutritional quality of SPM in the bays are relatively poor than in other more productive coastal waters in the world. Our results confirm that the measurement of a single chemical variable cannot describe fully the nutritive value of the seston available to suspension-feeders as previously proposed, and the biochemical composition of SPM can provide effective information on its origin and nutritive Quality.

• Korean Chemical Engineering Research
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• v.49 no.2
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• pp.256-262
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• 2011

Amine can undergo irreversible reactions by $O_{2}$ and high temperature in amine scrubbing process and these phenomena are called "degradation". Degradation causes not only a loss of valuable amine, but also operational problems such as foaming, corrosion and fouling. In this study, using various chemical absorbents(MEA; monoethanolamine, AMP; 2-amino-2-methyl-1-propanol, DAM; 1,8-diamino-p-menthane), we examined the following variable. I) loading ratio of $CO_{2}$ at $50^{\circ}C$ and $120^{\circ}C$, ii) concentration variation and initial degradation rate constant of absorbent in $CO_{2}$ and $CO_{2}/O_{2}$ system, and iii) effect of degradation by $O_{2}$. The $CO_{2}$ loading of 20 wt% DAM was 400% and 270% higher than that of 20 wt% MEA and AMP at 50, respectively and was the largest the difference of $CO_{2}$ loading between absorption $(50^{\circ}C)$ and regeneration $(120^{\circ}C)$ condition. The initial degradation rate constant of 20 wt% DAM was $2.254{\times}10^{-4}cycle^{-1}$ which was slower than that of MEA $(2.761{\times}10^{-4}cycle^{-1})$ and AMP $(2.461{\times}10^{-4}cycle^{-1})$ in $CO_{2}$ system. Also, it was increased 30% by $O_{2}$ that effects on the degradation by $O_{2}$ was less than 100% increased. these degradation reactions was able to identify by formation of new peak in GC and FT-IR spectrum analysis.

• Korea Journal of Hospital Management
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• v.8 no.1
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• pp.112-134
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• 2003

The purpose of this study is to analyze the consumer's expectation before the health care service and the consumer's satisfaction after it. The participants of the study are inpatients in a general hospital located in Seoul. The resources were collected from the self-administration questionnaire survey run parallel with face to face interview. In order to measure the degree of the consumer's expectation, 349 samples were collected from the first questionnaire survey on the date of admission to the hospital. The second questionnaire survey was carried out on the date of discharge to the hospital with the participants responding to the first questionnaire survey. There are 154 samples collected from this survey. The results from the analysis of these resources are as follow. First, the survey shows that one of the highest consumers' expectations was about the generosity, kindliness and sincerity from the staff at the hospital, specially from doctors. Second, according to the analysis of the factors affecting the expectations of the consumers, with regard to path of admission to a hospital relating to patient's features, outpatient who gets into a hospital expected good medical care much more than the other patients. In regard of doctor's features, patients usually and highly expect good medical care from doctors who have good carrier and much experience. Third, according to the second questionnaire survey, what patients are satisfied most with is about the generosity and sincerity from staff at a hospital, especially from doctors and their gem attitudes. The results from survey show that the differences among the degree of consumers' satisfaction are very variable, depending on surrounding environments and facilities. The only fact that expectation didn't meet with satisfaction appeared to the case about technology and skill of medical care and the case about updated medical skills and equipments. Fourth, comparing the degree of expectation with the degree of satisfaction of consumers, correlative analysis was concerned significantly and specifically about the part of overall cleanliness relating to facilities and surrounding environments, the items about medical examination and test plan procedure relating to skill of medical care, professional specialties and convenience for procedure, and the items about satisfying explanations and concern about patients from doctors relating to staff's generosity and sincerity. Fifth, the analysis of the factors affecting the degree of how much patients are satisfied with shows that relating to sociodemographical features, patients are not satisfied with the case when the time and process of medical treatment are getting longer. It is surveyed that consumer were satisfied with the motivation to visit a hospital and the insurance type in patient's feature and so were the medical department and the factor of the degree of the expectation in disease's feature. Sixth, according to analysis based on the survey, patients would join again a hospital when they get satisfaction from the medical care and also they want to come again regarding to doctor's capability. For example, when doctors are old, have a good carrier and much experience, patients would come again. As seen from the above, consumers are usually satisfied with the medical treatment more than that they expected before. They would intend to use again when they get satisfaction from the medical care provided at a hospital. Patients and consumers highly expect good attitude as well as capacity from medical doctors and they are also generally satisfied with those things. Therefore, in order to increase the degree of consumer's satisfaction and their intention to come again, the hospital staff would have to commit themselves to achieve high quality service continuously and would have to make an effort to offer the finest quality service.

• The Journal of Engineering Geology
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• v.22 no.3
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• pp.343-351
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• 2012

This study proposes a modified equation to calculate the factor of safety for an infinite slope considering the saturation depth ratio as a new variable calculated from rainfall infiltration into unsaturated soil. For the proposed equation, this study introduces the concepts of the saturation depth ratio and subsurface flow depth. Analysis of the factor of safety for an infinite slope is conducted by the sequential calculation of the effective upslope contributing area, subsurface flow depth, and the saturation depth ratio based on quasi-dynamic wetness index theory. The calculation process makes it possible to understand changes in the factor of safety and the infiltration behavior of individual rainfall events. This study analyzes stability changes in an infinite slope, considering the saturation depth ratio of soil, based on the proposed equation and the results of soil column tests performed by Park et al. (2011 a). The analysis results show that changes in the factor of safety are dependent on the saturation depth ratio, which reflects the rainfall infiltration into unsaturated weathered gneiss soil. Under continuous rainfall with intensities of 20 and 50 mm/h, the time taken for the factor of safety to decrease to less than 1.3 was 2.86-5.38 hours and 1.34-2.92 hours, respectively; in the case of repeated rainfall events, the time taken was between 3.27 and 5.61 hours. The results demonstrate that it is possible to understand changes in the factor of safety for an infinite slope dependent on the saturation depth ratio.

• Korean Journal of Veterinary Service
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• v.21 no.3
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• pp.285-300
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• 1998

1. The number of average milking cows, clinical forms of mastitis, mastitis-developing cows, and cows killed by mastitis a year were 25.7, 1.8(7%), 6.3(26%), and 2.7(10.1%)heads, respectively. The annual grade changes of standard plate counts(SPC) and somatic cell counts(SCC) showed the grade 1A of SPC diminished sharply from April to August, we think it was due to the lack of proper management in farming season and the grade 3 of SCC indirectly influenced increased in huge during August. 2. The average number of parturitions of farms was 2.3, but 50% of below 1 parturition were 22 farms(31%), 50% of above 3 parturitions were 16(23%) out of 71 farms. According to grades of the number of parturitions of milking cows per each farm, the farms' grades recording 3 parturitions and 50% were little bit excellent. 3. The actual situation research of foremilking CMT revealed 35 out of 74 farmer didn't do CMT Among them(35 out of 74 farmers), 80% did not test thanks to the troublesome process of the CMT. SCC grade 3, among farms who did foremilking CMT once or twice a month and who did not were 29% and 40% respectively and SPC grade 1A were 55% and 9%, respectively. 4. The research of actual situation on milking management let us know 29 farms(39%) did not do lastmilking, 37 farms(49%) usually did overmilking, and 34 farms(46%) did milking for 4 or 5 minutes. Grades according to average requiring times of milking showed SCC grade 1 of farms milking within 7 minutes was 11% and SPC grade 1A was 34%, on the other side, farms milking more than 7 minutes were 0% in SCC grade 1 and 13% in SPC grade 1A. Grades according to the starting time of milking after rubbing teats showed SPC grade 1A of farms starting milking at about 1 minute and over 2 minutes were 50% and 20%, respectively. 5. The research of actual situation on hygienic milking management uncovered 65 farms(88%) were using one towel which was used in washing teats and udders to wash more than 3 to 4 cows, and 53 farms(72%) were using one dried towel to dry udders not for each cow but for more than 3 to 4 cows after washing. Also, on milking turns disclosed 30 farms(40%) were milking cows in the order of incoming without isolation of a dominant group. According to grades of towels used in washing teats and udders, farms using a towel for each cow were 56% and a towel for over 3 cows were 31% in SPC grade 1A. According to using-or-not grades of dried towels after washing udders, farms using a towel for each cow were 79% and a towel for over 3 cows were 21% in SPC grade 1A. 6. Farms doing teat-dipping before milking were 7(10%), not doing teat-dipping after milking, or doing sometimes were 9(12%), and doing right after milking were 57(77%). And farms doing teat-dipping after dry cows and before delivery were 21(28a ). Farms using bethadine as an antiseptic solution were 70(95%), 40 farms(59%) diluted it with water as weak as 5 to 10 times, and on drying cows 64 farms(87%) slowly did it more than 2 days. Grade 1A of SPC of farms doing teat-dipping at every milking was 38%, farms doing occasionally or not was 33%, and farms doing it right after milking was 37% and doing after milking more than 5 cows was 20%. Grade 1A of SPC among farms diluting bethadine 5 times and diluting 5 to 10 times with water were 36% and 33%, respectively, and Grade 3 of SCC were 35% and 32%, respectively. 7. Studies on nonlactating period medical treatment, as the cows were on dry, 54 farms treated with their own hands.73 farms(98%) had bovine mastitis treated for themselves. And on applying medicines against mastitis, 55 farmers chose them on the basis of their own experience, 42 farms(57%) were treated more than 3 days. 41 farms(55%) dumped away the mastitis infected milk separately, 24 farms(32%) were feeding and milking at the same time. 8. Fifty-six farms(76%) always washed and disinfected milking machines after milking. Farms using the milking machines at low, or variable vacuum pressures, or at the vacuum pressure, set at the moment of its installation were 31(42%), and farms that did not know pulsation ratio were 27(37%). Farms changing liners when they were torn 8(11%), 58 farms(78%) said they checked milking system when there were wrong with them, 31 farms(42%) changed milking hoses when they found out problems, and 42 farms(57%) cleaned vacuum and milking systems when they felt dirty. The SPC grade 1A of farms washing and sterilizing milking machines was 38% and farms only washing was 28%.

• Journal of Sericultural and Entomological Science
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• v.2
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• pp.1-31
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• 1962

The purpose of this treatise is to prove the presence of cystine in silk fiber through wide sampling throughout all the sericultural processes of Bombyx mori.; also to show that disulfide cross linkages exist in the silk fiber. The conclusions reached were as follows: 1. Crystalline cystine was obtained from silk fibroin using Folin's Method. 2. Analytical data showing the cystine content of silk fiber and its related materials were obtained using Sullvan's Method as follows: Material Percent Cystine A. Mulberry leaf protein 0.175 B. Silkworm egg 0.33 C. Silkworm Body, matured, fat extracted, without silk gland 0.41 D. Silk gland, matured 1.23 E. Silkworm feces none F. Silkworm pupa, fat extracted 0.30 G. Silkworm moth, fat extracted 0.60 H. Raw Silk 0.22 I. Fibroin 0.175 J. Sericin 0.30 3. The presence of cystine in the silkworm was substantiated the existence of 0.175 % methionine in mulberry leaves and 0.12% methionine in the silk gland. 4. Part of the sulfhydryl compounds in the silk gland is believed to transfer to serine and methionine, with the former being secreted into the liquid silk finally as silk fiber and the latter used for nutritive purposes in the growing of silk gland tissue. 5. The cystine content is variable by mulberry species, silkworm species, sex, breeding process, and other culturing environments. 6. Hybrid silkworms require more nutritive amino acids for effective growth than the original parents, and secrete less of them as silk fiber. 7. From such an observation, the amino acid composition of silk fiber is believed to be fairly flexible. Cystine if included in the amorphous part of the fiber, especially in sericin. 8. The result from enriching the silkworm diet with pure cystine or wool cystine did not result in any advantage, therefore it is believed that the natural cystine and methionine contents in the mulberry leafaregoodenoughforsilkwormnutrition. 9. The disulfide cross linkage in silk fiber was verified by using the Harris Method. Contraction took place following the treatment of the fiber with various salts and acids. Comparisons were made with wool fiber. 10. During these experiments, the fibrious structure of silk fiber and the net-globular liquid form were photographed microscopically. It is believed that the globules of liquid silk are net-formed by the inter attraction of the OH ion of the globular peptide and the H ion of water as shown by the hair cracking behavior of the film. The net-globular protein precipitation from the mulberry protein solution showed that mulberry is a proper diet for the formation of fibrous protein in the silk fiber. 11. The significance of the presence of cystine in silk fiber as emphasized in this paper should result in modification of the general conception that cystine is absent from this fiber. NOTICE: A part of this treatise was presented at the annual Korea Sericultural Society meeting held in 1961.

• Asia pacific journal of information systems
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• v.19 no.2
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• pp.139-155
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• 2009

For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.