• The Journal of the Korean dental association
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• v.49 no.11
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• pp.688-703
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• 2011

Park Myoung Jin (1903-1957) was a respectable leader who disseminated dental medical education to make our path as the leading dental medical education developing a new global history of dental medicine. Dr. Park was born in Seoul on 3 July 1903. He graduated Kyongseong dental medical school and studied at the pharmacology department achieving his M.D. In 1938, as the president representing the Hanseong dentists association equivalent to the Japanese dentists association, Dr. Park participated in various events. After liberation, Dr. Park tried his best to achieve Korean dental medical education as the pursuit of ideal ego with self-centered ego. He reorganized the Kyongseong dental medical school and incorporated it to the Seoul National University dental college. Even during the Korea war, Dr. Park still sincerely carried out his duties as the director of the Seoul National University dental medical college by recruiting university entrants and turned out graduates. In 1954, Dr. Park as the director of the Seoul National University dental medical college, he frontiered an opportunity to adapt the American dental medicine by sending school staffs to study overseas. On 25 June 1954, Dr. Park received 25 years of meritorius service award presented by Seoul National University Dental Medical College. Further, on 6 Aril 1954, Dr. Park became a member of an academic research committee. In April 1946, Dr. Park was elected as the president of the Chosun Dentists Association(Korean Dental Association). On 19 May 1947, Dr. Park was also appointed as the director of the Korea dental medicine association leading the general meetings and academic conferences from 2nd through the 8th sessions. On 30 November 1954, as the president of the Korea dental medicine association, Dr. Park also published the Korea dental association publications. In 1957, Dr. Park donated the school housing for the principle of the Kyongseong dental medical school establishing the basis for the Korea dentists association center. Dr. Park also participated in establishment of the oral hygiene campaigne, dental administration policy, organization of the specialized subject delegation board members and the dental materials association. On 10 December 1955, we can recognize Dr. Park's respective historical consciousness through his declaration 'history is a true record of historical traces of a national'. Dr. Park was a living witness of the Korean dental industry. Especially, he stated that the origin of the Korean dentists association was in the Hanseong dentists association. Dr. Park overcame the pressure and indignity during the Japanese colonization. The joy of liberation did not last long since he also had to experience the fraticidal tragedy of the Korea war. Dr. Park was a professional dental specialist and a leader researching dental medicine. He was a great leader who understood the dental medicine and dedicated for the dentist association and dental medicine association with compassion for the nation and national as a Korean.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.11-19
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• 1999

This experiment was conducted with nine wheat geno-types to choose the wheat which has excellent early vigour. 'Vigour 18' and 'ZL 59A' are excellent in the long coleoptile genotype, while 'Amery' and 'Janz' are excellent in the short coleoptile genotype. Responding to the growth stage and nitrogen level, Vigour 18 is predominant in the long coleoptile genogype, while Janz in the short coleoptile genotype. Responding to sowing density and nitrogen level, the higher the sowing density was, the shorter the leaf area of Vigour 18 and Janz. Also the leaf area turned out to larger in the plot fertilized with high nitrogen than in the plot fertilized with low nitrogen. This is true of leaf weight and root weight. Concerning specific leaf area (SLA) and leaf area ratio (LAR), the higher the sowing density was, the SLA tended to grow larger, while the SLA grew larger in the plot fertilized with low nitrogen, as were found in Vigour 18 and Janz. The roots of long coleoptile genotype, Vigour 18, turned out to grow longest on the plot sown with 3 seeds. While the roots of short coleoptile genotype, Janz, grew longest on the plot sown with 2 seeds. The relative growth rate (RGR) was the same at low N rates and high N rates. The RGR was 0.071 and 0.072 g $g^{-1}d^{-1}$ at low N rates and high N rates. The partitioning of RGR into net assimilation rate (NAR) and LAR showed that the average LAR at low N rates was similar to the LAR at high N rates. Variation within each cultivar in the LAR and NAR was small relative to the difference between them at low N rates and high N rates. Above ground mass was 8.2 mg greater at high N rates than low N rates, whereas leaf area was 0.05 $\textrm{m}^2$$kg^{-l}$ greater at high N rates than low N rates. The NAR was similar at low N rates and high N rates, whereas LAR was greater at high N rates (0.05 $\textrm{m}^2$$kg^{-l}$); variation in SLA was responsible for the variation in NAR and LAR both at low N rates and high N rates. NAR was more closely associated with the reciprocal of SLA.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.5
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• pp.1-10
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• 2007

Most of natural images have a special property, what is called self-similarity, which is the basis of fractal image coding. Even though an image has local stationarity in several homogeneous regions, it is generally non-stationarysignal, especially in edge region. This is the main reason that poor results are induced in linear techniques. In order to overcome the difficulty we propose a non-linear technique using self-similarity in the image. In our work, an image is classified into stationary and non-stationary region with respect to sample variance. In case of stationary region, do-noising is performed as simply averaging of its neighborhoods. However, if the region is non-stationary region, stationalization is conducted as make a set of center pixels by similarity matching with respect to bMSE(block Mean Square Error). And then do-nosing is performed by Gaussian weighted averaging of center pixels of similar blocks, because the set of center pixels of similar blocks can be regarded as nearly stationary. The true image value is estimated by weighted average of the elements of the set. The experimental results show that our method has better performance and smaller variance than other methods as estimator.

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3874-3897
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• 2023

A high-fidelity computational fluid dynamics (CFD) analysis was performed using the Large Eddy Simulation (LES) model for the lower plenum of the High-Temperature Test Facility (HTTF), a ¼ scale test facility of the modular high temperature gas-cooled reactor (MHTGR) managed by Oregon State University. In most next-generation nuclear reactors, thermal stress due to thermal striping is one of the risks to be curiously considered. This is also true for HTGRs, especially since the exhaust helium gas temperature is high. In order to evaluate these risks and performance, organizations in the United States led by the OECD NEA are conducting a thermal hydraulic code benchmark for HTGR, and the test facility used for this benchmark is HTTF. HTTF can perform experiments in both normal and accident situations and provide high-quality experimental data. However, it is difficult to provide sufficient data for benchmarking through experiments, and there is a problem with the reliability of CFD analysis results based on Reynolds-averaged Navier-Stokes to analyze thermal hydraulic behavior without verification. To solve this problem, high-fidelity 3-D CFD analysis was performed using the LES model for HTTF. It was also verified that the LES model can properly simulate this jet mixing phenomenon via a unit cell test that provides experimental information. As a result of CFD analysis, the lower the dependency of the sub-grid scale model, the closer to the actual analysis result. In the case of unit cell test CFD analysis and HTTF CFD analysis, the volume-averaged sub-grid scale model dependency was calculated to be 13.0% and 9.16%, respectively. As a result of HTTF analysis, quantitative data of the fluid inside the HTTF lower plenum was provided in this paper. As a result of qualitative analysis, the temperature was highest at the center of the lower plenum, while the temperature fluctuation was highest near the edge of the lower plenum wall. The power spectral density of temperature was analyzed via fast Fourier transform (FFT) for specific points on the center and side of the lower plenum. FFT results did not reveal specific frequency-dominant temperature fluctuations in the center part. It was confirmed that the temperature power spectral density (PSD) at the top increased from the center to the wake. The vortex was visualized using the well-known scalar Q-criterion, and as a result, the closer to the outlet duct, the greater the influence of the mainstream, so that the inflow jet vortex was dissipated and mixed at the top of the lower plenum. Additionally, FFT analysis was performed on the support structure near the corner of the lower plenum with large temperature fluctuations, and as a result, it was confirmed that the temperature fluctuation of the flow did not have a significant effect near the corner wall. In addition, the vortices generated from the lower plenum to the outlet duct were identified in this paper. It is considered that the quantitative and qualitative results presented in this paper will serve as reference data for the benchmark.

• Journal of Korean Medical classics
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• v.4
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• pp.101-126
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• 1990

At early Cheong (淸) dynasty, in medical aspect by dependent on practical studying attitude that must found a theory only by an evidence, there had been a tendancy that hoped direct research of sages' mind-eye by escaping the theory of individual classes since Geum-Won (金-元) dynasty. Yoo Chang (喩昌), born in Man-Ryeok (萬曆) 12th year of Myung (明) dynasty (A.D.1583) and dead in Gang-Hee (康熙) 3rd year of Cheong (淸) dynasty (A.D.1664). The results were as follows after studying his practical idea of medicine. 1. Yoo Chang, by recognizing the ${\ll}$Sang-Han-Ro${\gg}$ has lost its true meaning after commented by Wang Hee (王熙), Lim Eog (林億), Seong Moo-I (成無巳), etc. according to Bang Yoo-Jip's (方有執) Chak-Gan-Jung-Jeong (錯簡重訂) theory, he diversified the protocal of ${\ll}$Sang-Han-Ro${\gg}$ 397 method and arranged under Six Meridian part. (六經) 2. The theory of Sam-Gang-Jeong-Rip (三綱鼎立) can be summerized Gye-Ji (桂枝) syndrome which is the case of Wind (風) has injured Wi (衛) stage, Ma-hwang (麻黃) syndrome which is the case of Cold (寒) has injured Yeong (榮) stage, Dae-Cheong-Ryong (大靑龍) syndrome which is the case both of Wind-Cold (風寒) has injured Yeong-Wi (榮衛) stage, and there has been Sam-Gang-Jeong-Rip theory by anterior medical practitioners already but the person who formally used its Sam-Gang-Jeong-Rip term is Yoo Chang. 3. Yoo Chang seized the On Byeng (溫病) by dividing three category and in Byon-Jeung-Si-Chi (辨證施治) he influenced to many aspect of establishment of later Byon-Jeung system On-Byong (溫病의 辨證體系) pertaining to Triple-Warmer by O-Dang (吳瑭) introducing Triple-Wanner Theory. (三焦理論) 4. At Chu-Jo-Ron (秋燥論) of ${\ll}$EUi-Moon-Beop-Ryo${\gg}$, while ${\ll}$Nae-Gyeong${\gg}$ describing if humidity injury Lung, then occur a disorder in it, Yoo Chang recognized that of au tuam when dryness injure Lung there occure a disorder is it so he insisted that at this case, must use Cheong-Joe-Goo-Pye method (淸操救肺法) withherbs, pertaing to Gam-Yoo-Ja-Yoon(甘柔滋潤性) property and he invented Cheong-Joe-Goo-Pye-Tang. (淸操救肺湯) 5. Yoo Chang', so called, Dae-Gi (大氣) indicates Yang-Gi (陽氣) of chest, he insisted that man's creation and every physiological activity depends on maintainence of Dae-Gi, and it integrate Yeong-Gi (榮氣), Wea-Gi (衛氣), Jong-Gi (宗氣), Jang-Boo-Ji-Gi (臟腑之氣), Gyeong-Rak-Ji-Gi. (經絡之氣) 6. Yoo Chang's expression about partical function and character of stomach, not only bolster its theory of historical physician's expression, that is stomach is. foundatness of postnatal period, but also it has corresponding aspect with modern medicine and clinic. 7. Yoo Chang emphasized "if one cure a disease, be must understood the character of disease first and use drugs later" (先議病 後用藥) phrase about of drug usage, and his theory of Geup-Rew-Man-Joo method (急流挽舟) and three therapy of Simple Ascite (單腹腸) are all unique opinion based upon this phrase mentioned above. 8. Yoo Chang's practical idea of medicine greatly influenced to Jang Ro (張璐), Hwang Won-A (黃元御), Oh Eui-Rak (吳儀洛), Joo Yang-Joon (周揚俊), etc. and theory of Sam-Gang-Jeng-Rip (三綱鼎立), Triple Warmer Theory of On Byong (溫疫의 三焦論治), Chu-Jo-Ron (秋燥論), Dae-Gi-Ron (大氣論) etc. became important object to student of Sang-Han (傷寒) and On-Byeng. (溫病) 9. Yoo Chang's Writings has more practical meaning than other physician's, especially, later the idea of Sang-Han (傷寒) and On-Byong (溫病) greatly contributed to development of Sang-Han theory and formation of On-Byong theory.

• Journal of Radiation Protection and Research
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• v.33 no.3
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• pp.105-112
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• 2008

To measure the soil-to-plant transfer factors ($TF_a,\;m^2\;kg^{-1}$-fresh) of radionuclides deposited during the growing season of potato, a radioactive solution containing $^{54}Mn,\;^{60}Co,\;^{85}Sr$ and $^{137}Cs$ was applied to the soil surfaces in soil boxes 2 d before seeding and three different times during the plant growth. For the pre-seeding application (PSA), radionuclides were mixed with the topsoil (loamy sand and 5.2 in pH). The plant parts investigated were leaves, stems, tuber skin and tuber flesh. The $TF_a$ values of $^{54}Mn,\;^{60}Co,\;^{85}Sr$ and $^{137}Cs$ from the PSA were in the ranges of $1.9{\times}10^{-4}{\sim}1.5{\times}10^{-2}$, $1.8{\times}10^{-4}{\sim}7.5{\times}10^{-4}$, $4.0{\times}10^{-4}{\sim}1.6{\times}10^{-2}$, $1.5{\times}10^{-4}{\sim}3.9{\times}10^{-4}$ respectively, for different plant parts. The TFa values from the growing-time applications were on the whole a few times lower than those from the PSA. For $^{54}Mn,\;^{85}Sr$ and $^{137}Cs$, the $TF_a$ values from the early- or middle-growth-stage application were higher than those from the late-growth-stage application, whereas the opposite was true for $^{60}Co$. Leaves and tuber flesh had the highest and lowest $TF_a$ values, respectively, in most cases. The total uptake from soil by the four plant parts was in the range of $0.05{\sim}3.16%$. In the third year following the PSA, the $TF_a$ values of $^{54}Mn,\;^{60}Co$ and $^{137}Cs$ were $11{\sim}25%$, $21{\sim}25%$ and $38{\sim}67%$ of those in the first year, respectively, depending on the plant parts. The present results can be used for estimating the radiological impact of an acute radioactive deposition during the growing season of potato and for testing the validity of relevant food-chain models.

• Journal of Nutrition and Health
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• v.6 no.1
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• pp.1-9
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• 1973

I. Subject of the Study: Studies on the economical nutrition supplement of cereal foods for the improvement in our notional eating habits. II. Purpose and Importance of the Study: 1. Our nation is confronted with the situation that the rice, a principal food, short of some essential amino acids, lysine and threonine, leads to imbalanced meals insufficient in the nutrient of protein, to bring many difficulties in the elevation of our national physique. 2. The shortage of even the rice imperfect in the nutrient of protein makes the import of lots of foreign rice inevitable. It is considered that the protein supplement and decrease in the consumption amount, of rice, is a serious key to the solution of our food difficulty, and then a way of the proetin supplement of rice through the addition of essential amino acid is to be rarely applied in the view of the our present finance and situation. 3. In the present experiment, therefore, it aims to the suggestion of an aspect of the improvement in our national eating habits guiding in the nutrition elevation which our nation can afford economically through the development of first, a way of the protein supplement by the mixture of cereals producted plentifully in our country, and second, a way of the decrease in the consumption amount and the improvement in the nutrition of rice through the substitution of the other cereals for rice. III. Contents of Scope of the Study: 1. Objects of the study: Objects of the study are the following three items; a) The nutrition supplement of rice through the mixture of cereals. Our nation makes mainly rice as a principal food, but practically many kinds of cereal are produced in our country. They contain different levels and qualities of each nutrient and they are different from one another in the kinds of essential amino acid consisting protein. For that reason, the mutual complement efficeincy of insufficient nutrients is observed through the mixture of cereals. b) The nutrition supplement of rice through the addition of superior protein sources to rice, a principal food. The development of rice as superior foods in the sense of nutrition is conducted through the risement in protein quality by the addition of protein sources in good quality, for example, fish flour (anchovy flour), egg powder, milk powder, and so on, and through the supplement of vitamins and minerals. c) The decrease in the consumption amount of rice through the substitution of the other cereals for rice, as a principal food. The compensation for the short amount of rice is made by the reduction in the consumption of rice through the discovery of a way of substitution of the other cereals for rice, as a principal food and of the settlement of problems in nutrition and finance subsequent to this. 2. Contents of the study: a) An ideal mixture-ratio of cereals is established for rats by feeding mixed foods(rice-barely or rice-wheat) containing 5%, 15%, 25%, 35% and 45% level of either barely or wheat. b) The nutritive value is determined in the whole subsititution of other foods for rice, and then, a way of the complement of over and under nutrients is devised. c) The ideal combination is investigated for rats through feeding mixed foods of main food, rice and supplement foods of protein sources, soy bean, fish flour, egg powder and milk Powder. d) According to results from the above three experiments, the concise functional test for men and the examination of economical property are made. 3. Scope of the study: a) The observation of the effect of each diet on the growth rate for rats. The growth rate of rats was observed for 15 groups of mixed foods of a main food, rice, and wheat flour, barley powder or soy bean powder, respectively, and 12 groups of wheat flour diets supplemented with $1{\sim}3%$ milk powder, and rice or wheat flour diets supplemented with 5% of milk powder, egg powder, fish flour or soy bean powder, respectively. b) The determination of food consumption. The food consumption was determined at weekly intervals for 27 kinds of diet described in a) item. c) The determination of food efficiency rate. The food efficiency rate for each diet was determined by calculation from the gained body weight and the food consumption amount at the same intervals described in b) item. d) The determination of protein efficiency rate. The protein efficiency rate for each diet was determined by calculation form gained body weight and the protein amount of the food consumption amount at the same intervals described c) item. e) The determination of the body component. The hematocrite and hemoglobin levels in the blood, total nitrogen in the serum, blood sugar, and lipids and glycogen in the liver were determined. f) The observation of nitrogen balance. As a means of the observation of nitrogen balance, the total nitrogen in the urine was determined. g) The analysis of economical property. The economical property was analyzed as the gained body weight to the amount equivalent to one won through the conversion of the food consumption amount into money. h) The functional test for men. The concise functional test for men was made in order to establish if the best diet for experimental animals can be applied to men. IV. Results of the Study: The national food product plan, nationwide nutritive enlightment and the improvement activities in our country eating habits, especially, mixed and powder food problems are to be significantly referred, and the following results must be applied. a) In the mixed foods of cereals, the mixed food of the rice-barley containing $5{\sim}15%$ level of barley is best in terms of nutrition. b) The addition of superior protein sources, egg, Bilk, soy bean, or fish, respectively to either rice or wheat flour makes a great risement in the nutritive value. c) The animal protein is more effective in the elevation of nutritive value of cereals. d) Rice takes the most nutritive operation and has the highest preference, among rice, wheat flour and barley. e) Wheat flour is more economical than rice in evaluation of the gained body weight to the regular money, and the addition of fish or soy bean is more economical than that of any other supplement food. But the above results are true of the range of nutrition and economical property. f) The study on the nutrition composition and barley will lead to the improvement in our national eating habits as mixed food of the rice-barley containing $5{\sim}15%$ level of barley is more nutritive. g) This study on the nutrition only for the growing animal can not be considered as a perfect and entire evaluation. Consequently, the perfect data for our national nutrition can be obtained from the experiment similar to this for the much longer period examining, in details, the growth rate, change of physical strength, mental and bodily change, average life span, and resistance ability to infectious diseases.

• Tuberculosis and Respiratory Diseases
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• v.54 no.4
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• pp.378-385
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• 2003

Background : Wheezing is an important clue in the diagnosis of asthma. Previously, a Korean National asthma survey used a written questionnaire, containing the question, "Have you ever experienced a breathing sound-like 'sack-sack' or a flute sound (the Korean description for wheezing) during the last 12 months?" The response to this question showed a large discrepancy between the prevalence of wheezing and physician diagnosed asthma. This might have resulted partly from a misunderstanding of the question, due to an inadequate description for wheezing. This study was aimed at finding how well the layman understands the term "wheezing" when described as a breathing sound-like 'sack-sack', a whistle or a flute. Subjects and method : Sixty subjects, without experience of wheezing(group I), and 45 subjects, with chronic cough alleging wheezing(group II), were recruited from the Hallym University's Sacred Heart Hospital, in Anyang, Korea. Four different breathing sounds; vesicular, wheezing, tracheobronchial and crackle, were played for the subjects, without any experience with wheezing, and they were asked "which sound is most like that you would imagine when asked about a breathing sound-like 'sack-sack', a whistle or a flute?" This was followed by replaying the true wheezing sound, and then a global assessment was requested for the concordance between the real wheezing sound and the imagined wheezing sound. The wheezing sound was played for those subjects alleging wheezing, and they were asked, "have you really experienced that sound". Results : Only 46.7% of group I answered correctly, with 13.3% choosing the vesicular sound, 16.7% the tracheobronchial sound, 5.0% the crackle and 18.3% failed to answer. The concordance between their imagined wheezing and the real sound was $69.3{\pm}22.4%(mean{\pm}S.D.)$. 77.8% of group II recognized the correct sound as the one they had experienced. Conclusions : Language is not sufficient to the layman for describing natural sounds, such as wheezing.

• Journal of Intelligence and Information Systems
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• v.24 no.3
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• pp.67-88
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• 2018

Until recently, as we recognize the significance of sustainable growth and competitiveness of small-and-medium sized enterprises (SMEs), governmental support for tangible resources such as R&D, manpower, funds, etc. has been mainly provided. However, it is also true that the inefficiency of support systems such as underestimated or redundant support has been raised because there exist conflicting policies in terms of appropriateness, effectiveness and efficiency of business support. From the perspective of the government or a company, we believe that due to limited resources of SMEs technology development and capacity enhancement through collaboration with external sources is the basis for creating competitive advantage for companies, and also emphasize value creation activities for it. This is why value chain network analysis is necessary in order to analyze inter-company deal relationships from a series of value chains and visualize results through establishing knowledge ecosystems at the corporate level. There exist Technology Opportunity Discovery (TOD) system that provides information on relevant products or technology status of companies with patents through retrievals over patent, product, or company name, CRETOP and KISLINE which both allow to view company (financial) information and credit information, but there exists no online system that provides a list of similar (competitive) companies based on the analysis of value chain network or information on potential clients or demanders that can have business deals in future. Therefore, we focus on the "Value Chain Network System (VCNS)", a support partner for planning the corporate business strategy developed and managed by KISTI, and investigate the types of embedded network-based analysis modules, databases (D/Bs) to support them, and how to utilize the system efficiently. Further we explore the function of network visualization in intelligent value chain analysis system which becomes the core information to understand industrial structure ystem and to develop a company's new product development. In order for a company to have the competitive superiority over other companies, it is necessary to identify who are the competitors with patents or products currently being produced, and searching for similar companies or competitors by each type of industry is the key to securing competitiveness in the commercialization of the target company. In addition, transaction information, which becomes business activity between companies, plays an important role in providing information regarding potential customers when both parties enter similar fields together. Identifying a competitor at the enterprise or industry level by using a network map based on such inter-company sales information can be implemented as a core module of value chain analysis. The Value Chain Network System (VCNS) combines the concepts of value chain and industrial structure analysis with corporate information simply collected to date, so that it can grasp not only the market competition situation of individual companies but also the value chain relationship of a specific industry. Especially, it can be useful as an information analysis tool at the corporate level such as identification of industry structure, identification of competitor trends, analysis of competitors, locating suppliers (sellers) and demanders (buyers), industry trends by item, finding promising items, finding new entrants, finding core companies and items by value chain, and recognizing the patents with corresponding companies, etc. In addition, based on the objectivity and reliability of the analysis results from transaction deals information and financial data, it is expected that value chain network system will be utilized for various purposes such as information support for business evaluation, R&D decision support and mid-term or short-term demand forecasting, in particular to more than 15,000 member companies in Korea, employees in R&D service sectors government-funded research institutes and public organizations. In order to strengthen business competitiveness of companies, technology, patent and market information have been provided so far mainly by government agencies and private research-and-development service companies. This service has been presented in frames of patent analysis (mainly for rating, quantitative analysis) or market analysis (for market prediction and demand forecasting based on market reports). However, there was a limitation to solving the lack of information, which is one of the difficulties that firms in Korea often face in the stage of commercialization. In particular, it is much more difficult to obtain information about competitors and potential candidates. In this study, the real-time value chain analysis and visualization service module based on the proposed network map and the data in hands is compared with the expected market share, estimated sales volume, contact information (which implies potential suppliers for raw material / parts, and potential demanders for complete products / modules). In future research, we intend to carry out the in-depth research for further investigating the indices of competitive factors through participation of research subjects and newly developing competitive indices for competitors or substitute items, and to additively promoting with data mining techniques and algorithms for improving the performance of VCNS.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.8-12
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• 1974

1. If one unity is given to the prongs whose ends touch each other for estimating the internal stresses occuring in it, the internal stresses which are developed in the open prongs can be evaluated by the ratio to the unity. In accordance with the above statement, an equation was derived as follows. For employing this equation, the prongs should be made as shown in Fig. I, and be measured A and B' as indicated in Fig. l. A more precise value will result as the angle (J becomes smaller. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ where A is thickness of the prong, B' is the distance between the two prongs shown in Fig. 1 and CH is the value of internal stress expressed by percentage. It precision is not required, the equation can be simplified as follows. $CH=\frac{A-B'}{A}{\times}200%$ 2. Under scheduled drying condition III the kiln, when the weight of a sample board is constant, the moisture content of the shell of a sample board in the case of a normal casehardening is lower than that of the equilibrium moisture content which is indicated by the Forest Products Laboratory, U. S. Department of Agriculture. This result is usually true, especially in a thin sample board. A thick unseasoned or reverse casehardened sample does not follow in the above statement. 3. The results in the comparison of drying rate with five different kinds of wood given in Table 1 show that the these drying rates, i.e., the quantity of water evaporated from the surface area of I centimeter square per hour, are graded by the order of their magnitude as follows. (1) Ginkgo biloba Linne (2) Diospyros Kaki Thumberg. (3) Pinus densiflora Sieb. et Zucc. (4) Larix kaempheri Sargent (5) Castanea crenata Sieb. et Zucc. It is shown, for example, that at the moisture content of 20 percent the highest value revealed by the Ginkgo biloba is in the order of 3.8 times as great as that for Castanea crenata Sieb. & Zucc. which has the lowest value. Especially below the moisture content of 26 percent, the drying rate, i.e., the function of moisture content in percentage, is represented by the linear equation. All of these linear equations are highly significant in testing the confficient of X i. e., moisture content in percentage. In the Table 2, the symbols are expressed as follows; Y is the quantity of water evaporated from the surface area of 1 centimeter square per hour, and X is the moisture content of the percentage. The drying rate is plotted against the moisture content of the percentage as in Fig. 2. 4. One hundred times the ratio(P%) of the number of samples occuring in the CH 4 class (from 76 to 100% of CH ratio) within the total number of saplmes tested to those of the total which underlie the given SR ratio is measured in Table 3. (The 9% indicated above is assumed as the danger probability in percentage). In summarizing above results, the conclusion is in Table 4. NOTE: In Table 4, the column numbers such as 1. 2 and 3 imply as follows, respectively. 1) The minimum SR ratio which does not reveal the CH 4, class is indicated as in the column 1. 2) The extent of SR ratio which is confined in the safety allowance of 30 percent is shown in the column 2. 3) The lowest limitation of SR ratio which gives the most danger probability of 100 percent is shown in column 3. In analyzing above results, it is clear that chestnut and larch easly form internal stress in comparison with persimmon and pine. However, in considering the fact that the revers, casehardening occured in fir and ginkgo, under the same drying condition with the others, it is deduced that fir and ginkgo form normal casehardening with difficulty in comparison with the other species tested. 5. All kinds of drying defects except casehardening are developed when the internal stresses are in excess of the ultimate strength of material in the case of long-lime loading. Under the drying condition at temperature of $170^{\circ}F$ and the lower humidity. the drying defects are not so severe. However, under the same conditions at $200^{\circ}F$, the lower humidity and not end coated, all sample boards develop severe drying defects. Especially the chestnut was very prone to form the drying defects such as casehardening and splitting.