• Journal of radiological science and technology
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• v.36 no.4
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• pp.313-318
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• 2013

Positron emission tomography/computed tomography (PET/CT) imaging with fluorodeoxyglucose (FDG) have been used as a powerful fusion modality in nuclear medicine not only for detecting cancer but also for staging and therapy monitoring. Nevertheless, there are various causes of FDG uptake in normal and/or benign tissues. The purpose of present study was to investigate whether additional delayed imaging can improve the diagnosis to differentiate the rates of FDG uptake at axillary lymph nodes (ALN) between malignant and benign in breast cancer patients. 180 PET/CT images were obtained for 27 patients with ALN uptake. The patients who had radiotherapy and chemotherapy were excluded from the study. $^{18}F$-FDG PET/CT scan at 50 min (early phase) and 90 min (delayed phase) after $^{18}F$-FDG injection were included in this retrospective study. The staging of cancers was confirmed by final clinical according to radiologic follow-up and pathologic findings. The standardized uptake value (SUV) of ALN was measured at the Syngo Acquisition Workplace by Siemens. The 27 patients included 18 malignant and 9 ALN benign groups and the 18 malignant groups were classified into the 3 groups according to number of metastatic ALN in each patient. ALNs were categorized less than or equal 3 as N1, between 4 to 9 as N2 and more than 10 as N3 group. Results are expressed as the mean${\pm}$standard deviation (S.D.) and statistically analyzed by SPSS. As a result, Retention index (RI-SUV max) in metastasis was significantly higher than that in non-metastasis about 5 fold increased. On the other hand, RI-SUV max in N group tended to decrease gradually from N1 to N3. However, we could not prove significance statistically in malignant group with ANOVA. As a consequence, RI-SUV max was good indicator for differentiating ALN positive group from node negative group in breast cancer patients. These results show that dual-time-point scan appears to be useful in distinguishing malignant from benign.

• Journal of the Korean Society of Costume
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• v.2
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• pp.73-88
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• 1978

This article is an attempt to explain, at least in part, the contemporary Korean women's consciousness of Western Dreasses. As time changes, the role of clothing undergoes varisous transitions, while values and ways of life are constantly in change. It is, therefore, proper and appropriate to recognize as among the major aspects of social psychology such phenomenon as interests, understanding of clothing, the choice of a dress, and attitudes toward clothing, etc. The purpose of this study is to discover problems concerning and their clothing and their solutions, by means of a surveying approach. The method of research used is based upon questionares distributed to parents of first-year pupils in elementary schools and to female clerks working in offices, covering the period from August through October, 1976. The number of the questionares distrubuted totalled 600, and 526 were returned to the research to be utilized for analysis. The contents of the survey included such things as values concerning clothing, kinds of clothing and their practical use, the selection of clothing and the method of purchase, fashions, etc. The classification of aquisition are self-made clothing, clothing made to order and ready-made materials. It is composed of 25 items, including affirmative reasons as well as negative ones. The processing of the material returned was made by using the computer, and based upon classifications such as ages, monthly income, occupations; thus diagraming the result in percentages. The conclusion made and the improvements proposed are as follows: 1. The values of clothing were placed on the expression of the wearer's personality (32.7) and on eauty(28. 6%). The lower age group places is stress upon the expression of personality, while the higher age group stresses beauty. About 50% of wearers are contented with their clothing, their clothing, the rest of whom them indicating their dissatisfaction with what they wear. As to designs at the time of selection, about 46% indicated their preference of personal expression, 31.8% on usefulness. In selecting material, practicality is emphasized; in selecting patterns, single color is preferred. In short, personal expression and esthetic values are primary, with consideration of practicality in mind. 2. The classification of clothing according to their uses indicates the highest numbers in normal wear (home wears) and clothings to be worn outside home. As to evening dresses, (party dress) only one or two articles were checked by many, and no such article was clamed to be possessed by most. The highest ratio of wearing was shown in the case of home wear (47.3%) and clothing to be worn outside the home, which is 55.8%. The budget for one article of clothing was greatest in the case of home wear, and clothing worn outside the home. Many used both kinds of articles for the same purpose. It is desirable, therefore, that the kinds of clothing should be varied according to the purpose for which they are worn, and that clothing appropriate for that purpose should be worn. 3. The motivation for purchasing clothing was highly chosen in the item of seasonal change, which was 55.7%; Clothing deliberately made was indicated by 45.2%. In the mothods of purchasing clothing, clothing made to order and ready-made was indicated by 44.4%, which is the highest; Clothing made to order was 25.4%, and self-sewing was 1.1%, which is the lowest. (1) In the case of self-sewing, "I like it but it is very hard," was checked by 43.6%; "It is so difficult that I cannot wear such clothing" was checked by 13.3%. From these, we can conclude that the questionees are willing to make clothing by themselves, but techniques involved in sewing and at her problems involved in the skill are complicated but when those problems are eliminated there is a possibility for practice. The response checked by questionees concerning the self-sewing was, "It's economical", which is a clear indication that many questionees are positive for self-sewing. It is generally believed that ready-made clothing is cheaper, but it is not necessarily so. In consideration of the quality of clothing, self-sewing is a necessity, and it is desirable that it should be encouraged. (3) Problems involved in ready-made clothing, such as designs, skills, size (fitting) should be eliminated. When these problems are scientifically gotten rid of, it is possible that affirmative returns will be expected. Affirmative responses such as "Ready-made clothing is economical," "You can select there on the spot," are good signs that many women expect to wear ready-made clothing. It is in this sense that the prospect for ready-made clothing is brighter when much development for ready-made clothing is on the way. 4. Much concern for fashion are checked in such item of questions as "Fashionable clothing in the show window," "Clothes worn by women." The first item was checked by 50.1 %, and the second was checked by 48.6%. The reason for following fashion is "Because many people wear them," which was indicated by 30.4%. The reason for not following fashion is "It is too expensive," which was checked by 29.6%. The 26.2% of the answers indicated that "Fashionable clothing is devoid of personality," The influences of fashion over the development of fashion over the development of clothing are two-fold: Esthetic and active. It is not to be deniable that people follow fashion more or less. 1978.9>

• Journal of Korean Society of Forest Science
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• v.82 no.4
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• pp.311-318
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• 1993

This study was conducted to obtain necessary information to improve beekeeping farmhouses management and to establish related problem. Using data obtained from 50 beekeeping farmhouses in Korea, current status of management and optimum sales scale were analysed. The results of the study are summarized as follows ; 1. Managers of beekeeping farmhouses are relatively old(64% of them is over 50 years old) and highly educated and experienced(76% of them is in the business more than 10 years). 2. Only a portion of managers(38%) considers beekeeping as a major job, while the rest(62%) involves as a side job working with other agricultural business. 3. Major supply of labor force comes from family group. Total input of family labor is 6.4 months a year. Fourty-four percent of management units is migrating and 56% of them is settled in specific locations. 4. In 1991, the average number of conventional beehive casks per farmhouse is decreased by 2.94 casks but improved-type beehive casks is increased by 13.79 casks. Total number of beehive casks per farmhouse is increased by 12.66 casks during the year. 5. Major cost items of beekeeping farmhouses include bee colony aquisition cost, feeding cost, depreciation cost, wages in an order. The average yearly profit rate of farmhouses is about 29.4%. 6. The break-even point of honey sales is about 3 million won. The optimum sales scale was 52.2l, then average production cost was estimated 53,800Won.

• Hwankyungkyoyuk
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• v.6 no.1
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• pp.63-99
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• 1994

The international environmental activities and environmental education began in 1970's. Environmental education in Korea was emphasized since the Forth National Curriculum. 'The Environmental Education Curriculum' will be separated as one of the most important parts in the Sixth National Education Curriculum in Korea. The purpose of this study was development. of 'Environmental Science' of high school appropriate to Sixth National Education Curriculum. First step was to state goals of environmental education in detail based on analysis of goals about environmental education in our country and other countries. Second was to analyse seven environments-related texts of Korea, America and England. Third, to measure how much environmental education has achieved in Fifth National Curriculum of Korea. Fourth, to develop a new environmental text of high school level. Fifth, to verify the effect of developed environmental text. The environmental part of 'Science I'(unit V. Life and Environments) and high school environments-related reference text(Survival and Environments) in Korea, American knowledges. American 'Environments' was stressed in many skills but they didn't include various teaching strategies. On the other hand, American 'Science-Technology-Society(S-T-S)' and British 'Science and Technology in Society(SATIS)' were stressed in knowledges and skills, and they included many teaching strategies and student actions. American 'S-T-S' was the only one stressed in values and attitudes. And all seven texts were not interested in behaviors and participations. To measure the achievement of environmental education by questionnaire, 497 high school students in total were selected from five different schools. Actually, most students had a positive thinkings and attitudes in their hearts about environmental problems, about environmental problems, but many of them did not take actions to solve environmental problems and to protect environments. The higher the score students got in 'knowledges and informations', the higher the score in 'skill'. It implies that learning of skills is based on learning of knowledges and informations about environments. On the other hand, much knowledges and information about environments has not always ensured positive thinkings and attitudes or active behaviors and participations to solve environmental problem. In view that ultimate aim of environmental education is forming responsible environmental behaviors and the goals of values and behaviors are as important as knowledges and skills. A new environmental text of high school level was developed and it was based on analysis of seven texts and environmental education in Fifth Korean Curriculum. This text have seven units, 1. Habitates : What're the meanings?, 2. Nuclear Energy : Can't be Avoid?, 3. Acid Rain : What're the Messages?, 4. Ethanol : Is this Future Fuel?, 5. Wastes : A New War!, 6. What're the National and Gloval Environmental education and avoided from the array of knowledges. Therefore included various teaching strategies and independent actions of students. 'Open-ended value learning' and 'free behavior learning' in text were special learning parts for aquisition of values and formation of behaviors. To verify the effects. of new developed environmental text, the direct learning was carried out by 286 students in total. Post test scores of experimental groups per each units were significantly higher than those of control groups from five different schools were as follows. For validity of selecting contents for units, 74% of respondent replied positively. For classification and presentation of four goal-groups, 90% replied positively in validity and 82%, in utility. For validity of various teaching strategies, 88% and for the degree of including student-centered independent actions, 86% replied positively, For importances and expected effects of 'open=ended value learning' and 'free behavior learning', showed positive responses respectively, 88%, 92% Therefore this text is effective to achieve four goals of environmental education equally.

• Sleep Medicine and Psychophysiology
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• v.6 no.1
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• pp.52-60
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• 1999

Objectives: With the object of finding the appropriate conditions and algorithms for dimensional analysis of human EEG, we calculated correlation dimensions in the various condition of sampling rate and data aquisition time and improved the computation algorithm by taking advantage of bit operation instead of log operation. Methods: EEG signals from 13 scalp lead of a man were digitized with A-D converter under the condition of 12 bit resolution and 1000 Hertz of sampling rate during 32 seconds. From the original data, we made 15 time series data which have different sampling rate of 62.5, 125, 250, 500, 1000 hertz and data acqusition time of 10, 20, 30 second, respectively. New algorithm to shorten the calculation time using bit operation and the Least Trimmed Squares(LTS) estimator to get the optimal slope was applied to these data. Results: The values of the correlation dimension showed the increasing pattern as the data acquisition time becomes longer. The data with sampling rate of 62.5 Hz showed the highest value of correlation dimension regardless of sampling time but the correlation dimension at other sampling rates revealed similar values. The computation with bit operation instead of log operation had a statistically significant effect of shortening of calculation time and LTS method estimated more stably the slope of correlation dimension than the Least Squares estimator. Conclusion: The bit operation and LTS methods were successfully utilized to time-saving and efficient calculation of correlation dimension. In addition, time series of 20-sec length with sampling rate of 125 Hz was adequate to estimate the dimensional complexity of human EEG.

• The Korean Journal of Archival Studies
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• no.28
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• pp.35-81
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• 2011

Manhwa is a mass media (to expose all faces of an era such as politics, society, cultures, etc with the methodology of irony, parody, etc). Since the Manhwa records is primary culture infrastructure, it can create the high value-added industry by connecting with fancy, character, game, movie, drama, theme park, advertising business. However, due to lack of active and systematic aquisition system, as precious Manhwa manuscript is being lost every year and the contents hard to preserve such as Manhwa content in the form of electronic records are increasing, the countermeasure of Manhwa contents management is needed desperately. In this study, based on these perceptions, the need of Manhwa records management is examined, and the characteristics and the components of Manhwa records were analyzed. And at the same time, the functions of record management process reflecting the characteristics of Manhwa records were extracted by analyzing various cases of overseas Cartoon Archives. And then, the framework of record-keeping regime was segmented into each of acquisition management service areas and the general Manhwa records archiving strategy, which manages the Manhwa contents records, was established and suggested. The acquired Manhwa content records will secure the context among records and warrant the preservation of records and provide diverse access points by reflecting multi classification and multi-level descriptive element. The Manhwa records completed the intellectual arrangement will be preserved after the conservation in an environment equipped with preservation facilities or preserved using digital format in case of electronic records or when there is potential risk of damaging the records. Since the purpose of the Manhwa records is to use them, the information may be provided to diverse classes of users through the exhibition, the distribution, and the development of archival information content. Since the term of "Manhwa records" is unfamiliar yet and almost no study has been conducted in the perspective of records management, it will be the limit of this study only presenting acquisition strategy, management and service strategy of Manhwa contents and suggesting simple examples. However, if Manhwa records management strategy are possibly introduced practically to Manhwa manuscript repositories through archival approach, it will allow systematic acquisition, preservation, arrangement of Manhwa records and will contribute greatly to form a foundation for future Korean culture contents management.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.2
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• pp.1-13
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• 2019

As a way to find new and innovative technologies, many companies have invested in and acquired skilled startups. Because startups are usually small in size and have a small history of past business experience, there are many risks involved in acquiring them as they have limited technical skills and business feasibility verification methods. Thus, venture capital plays an important role in discovering and investing competitive startups. While Independent Venture Capital generally values financial returns, Corporate Venture Capital, which plays investment roles in the firm, values business synergies with the parent company from a strategic perspective. In an industry sector where development of technology is rapid and whether new technology is held determines a company's competitiveness, existing companies incorporate startups with innovative technologies into their investment portfolios, collaborate together, and take over for comprehensive cooperation. In addition, new investments and acquisitions are carried out through the management of portfolio companies to obtain and utilize industry information. In this paper, major U.S. companies listed in the U.S. verified their investment activities through corporate venture capital and their impact on parent companies and startups through regression, while the parent company's acquisition performance was analyzed through an event study based on a stock price analysis. The criteria for startup were defined as companies with less than 12 years of experience, and the analysis showed that the parent companies with corporate venture capital with a larger number of investments actively take over startups. In addition, increasing corporate venture capital's financial investment activities shows a negative impact on the parent companies' acquisition activities, and the acquisition performance increased when the parent companies took over startups in its portfolio.

• Journal of radiological science and technology
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• v.35 no.3
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• pp.265-273
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• 2012

Aquisition of accurate beam data is very important to calculate a reliable dose distribution of the treatment planning system for small radiation fields in intensity-modulated radiation therapy(IMRT) and stereotactic radiosurgery(SRS). For the measurement of small fields, the choice of a suitable detector is important due to the shape gradient in profile penumbra, the lack of lateral electronic equilibrium, and the effect of effective detector volume. Therefore, this study was to analyze the dosimetric characteristics of various detectors in measurement of beam data for small fields of linear accelerator. 0.01cc and 0.13cc ion chambers (CC01 and CC13) and a stereotactic diode detector(SFD) were used for measurement of small fields. The beam data, including the percent depth dose, output factor, and beam profile were acquired under 6 MV and 15 MV photon beams. Measurements were performed with the field size ranging from $2{\times}2cm^2$ to $5{\times}5cm^2$. For $2{\times}2cm^2$ field size, the differences of the ratios of $PDD_{20}$ and $PDD_{10}$ measured by CC01 and SFD detectors were 1.02% and 0.12% for 6 MV and 15 MV photon beams, respectively. For field sizes larger than $3{\times}3cm^2$, the differences of values of $PDD_{20}/PDD_{10}$ obtained from each detector were 1.15% and 0.71% for 6 MV and 15 MV photon beams, respectively. The output factors obtained from CC01 and SFD for $2{\times}2cm^2$ field size were within 0.5% and 1.5% for 6 MV and 15 MV, respectively. The differences in output factor of three detectors for $3{\times}3cm^2$ to $5{\times}5cm^2$ field sizes were within 0.5%. Profile penumbras measured by the SFD, CC01, and CC13 detectors at three depths were average 2.7 mm and 3.5 mm, 3.4 mm and 4.3 mm, and 5.2 mm and 6.1 mm for 6 MV and 15 MV photon beams, respectively. In conclusion, it could be possible to use of the CC01 and SFD detectors for the measurement of percent depth dose and output factor for $2{\times}2cm^2$ field size, and to use of three detectors for $3{\times}3cm^2$ to $5{\times}5cm^2$ field sizes. CC01 and SFD detectors, consider ably smaller than the radiation field, should be used in order to accurately measure the profile penumbra for small field sizes.

• The Korean Journal of Nuclear Medicine Technology
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• v.25 no.2
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• pp.15-24
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• 2021

Purpose SPECT/CT was noted for its excellent correction method and qualitative functions based on fusion images in the early stages of dissemination, and interest in and utilization of quantitative functions has been increasing with the recent introduction of companion diagnostic therapy(Theranostics). Unlike PET/CT, various conditions like the type of collimator and detector rotation are a challenging factor for image acquisition and reconstruction methods at absolute quantification of SPECT/CT. Therefore, in this study, We want to find out the effect on the radioactivity concentration estimate by the increase or decrease of the total acquisition time according to the number of projections and the acquisition time per projection among SPECT/CT imaging conditions. Materials and Methods After filling the 9,293 ml cylindrical phantom with sterile water and diluting 99mTc 91.76 MBq, the standard image was taken with a total acquisition time of 600 sec (10 sec/frame × 120 frames, matrix size 128 × 128) and also volume sensitivity and the calibration factor was verified. Based on the standard image, the comparative images were obtained by increasing or decreasing the total acquisition time. namely 60 (-90%), 150 (-75%), 300 (-50%), 450 (-25%), 900 (+50%), and 1200 (+100%) sec. For each image detail, the acquisition time(sec/frame) per projection was set to 1.0, 2.5, 5.0, 7.5, 15.0 and 20.0 sec (fixed number of projections: 120 frame) and the number of projection images was set to 12, 30, 60, 90, 180 and 240 frames(fixed time per projection:10 sec). Based on the coefficients measured through the volume of interest in each acquired image, the percentage of variation about the contrast to noise ratio (CNR) was determined as a qualitative assessment, and the quantitative assessment was conducted through the percentage of variation of the radioactivity concentration estimate. At this time, the relationship between the radioactivity concentration estimate (cps/ml) and the actual radioactivity concentration (Bq/ml) was compared and analyzed using the recovery coefficient (RC_Recovery Coefficients) as an indicator. Results The results [CNR, radioactivity Concentration, RC] by the change in the number of projections for each increase or decrease rate (-90%, -75%, -50%, -25%, +50%, +100%) of total acquisition time are as follows. [-89.5%, +3.90%, 1.04] at -90%, [-77.9%, +2.71%, 1.03] at -75%, [-55.6%, +1.85%, 1.02] at -50%, [-33.6%, +1.37%, 1.01] at -25%, [-33.7%, +0.71%, 1.01] at +50%, [+93.2%, +0.32%, 1.00] at +100%. and also The results [CNR, radioactivity Concentration, RC] by the acquisition time change for each increase or decrease rate (-90%, -75%, -50%, -25%, +50%, +100%) of total acquisition time are as follows. [-89.3%, -3.55%, 0.96] at - 90%, [-73.4%, -0.17%, 1.00] at -75%, [-49.6%, -0.34%, 1.00] at -50%, [-24.9%, 0.03%, 1.00] at -25%, [+49.3%, -0.04%, 1.00] at +50%, [+99.0%, +0.11%, 1.00] at +100%. Conclusion In SPECT/CT, the total coefficient obtained according to the increase or decrease of the total acquisition time and the resulting image quality (CNR) showed a pattern that changed proportionally. On the other hand, quantitative evaluations through absolute quantification showed a change of less than 5% (-3.55 to +3.90%) under all experimental conditions, maintaining quantitative accuracy (RC 0.96 to 1.04). Considering the reduction of the total acquisition time rather than the increasing of the image acquiring time, The reduction in total acquisition time is applicable to quantitative analysis without significant loss and is judged to be clinically effective. This study shows that when increasing or decreasing of total acquisition time, changes in acquisition time per projection have fewer fluctuations that occur in qualitative and quantitative condition changes than the change in the number of projections under the same scanning time conditions.