• Journal of IKEEE
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• v.22 no.2
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• pp.408-412
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• 2018

In this paper, a 26GHz variable gain amplifier fabricated using a 40nm CMOS process is studied. In the case of an automobile radar using 79 GHz, it is advantageous in designing and driving to drive down to a low frequency band or to use a low frequency band before up conversion rather than designing and matching the entire circuit to 79 GHz in terms of frequency characteristics. In the case of a Phased Array System that uses time delay through TTD (True Time Delay) in practice, down conversion to a lower frequency is advantageous in realizing a real time delay and reducing errors. For a VGA (Variable Gain Amplifier) operating in the 26GHz frequency band that is 1/3 of the frequency of 79GHz, VDD : 1V, Bias 0.95V, S11 is designed to be <-9.8dB (Mea. High gain mode) and S22 < (Mea. high gain mode), Gain: 2.69dB (Mea. high gain mode), and P1dB: -15 dBm (Mea. high gain mode). In low gain mode, S11 is <-3.3dB (Mea. Low gain mode), S22 <-8.6dB (Mea. low gain mode), Gain: 0dB (Mea. low gain mode), P1dB: -21dBm (Mea. Low gain mode).

• Journal of the Korean Society for information Management
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• v.31 no.2
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• pp.57-77
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• 2014

As co-authorship has been prevalent within science communities, counting the credit of co-authors appropriately is an important consideration, particularly in the context of identifying the knowledge structure of fields with author-based analysis. The purpose of this study is to compare the characteristics of co-author credit counting methods by utilizing correlations, multidimensional scaling, and pathfinder networks. To achieve this purpose, this study analyzed a dataset of 2,014 journal articles and 3,892 cited authors from the Journal of the Architectural Institute of Korea: Planning & Design from 2003 to 2008 in the field of Architecture in Korea. In this study, six different methods of crediting co-authors are selected for comparative analyses. These methods are first-author counting (m1), straight full counting (m2), and fractional counting (m3), proportional counting with a total score of 1 (m4), proportional counting with a total score between 1 and 2 (m5), and first-author-weighted fractional counting (m6). As shown in the data analysis, m1 and m2 are found as extreme opposites, since m1 counts only first authors and m2 assigns all co-authors equally with a credit score of 1. With correlation and multidimensional scaling analyses, among five counting methods (from m2 to m6), a group of counting methods including m3, m4, and m5 are found to be relatively similar. When the knowledge structure is visualized with pathfinder network, the knowledge structure networks from different counting methods are differently presented due to the connections of individual links. In addition, the internal validity shows that first-author-weighted fractional counting (m6) might be considered a better method to author clustering. Findings demonstrate that different co-author counting methods influence the network results of knowledge structure and a better counting method is revealed for author clustering.

• Journal of Technology Innovation
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• v.25 no.3
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• pp.155-195
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• 2017

The goal of the present study is reviewing the literature on the scientific community and also on science, technology & society to increase interactions between innovation studies and social studies of science and technology. Up until now, various empirical studies on Korean scientists and engineers have been concentrated on researchers at universities, while they have paid inadequate attention to researchers at state-funded research institutes and private companies. In addition, these studies have tended to use concepts in Western academia to elucidate Korean cases. On the other hand, recent empirical researches on the effects of the evaluation systems in universities, PBS system, and the network of school ties suggest that these topics may reveal the unique characteristics of Korean scientific community. Empirical studies on the scientific community have also shown that Korean research institutes and researchers who are in charge of innovation in Korea have demonstrated a tendency to conform to the government's guidance due to long experiences of state-led R&D and nationalism. Research on science, technology and society has viewed the participation of citizens in science and technology as a way toward science and technology democracy, and tended to have a strong practical orientation. However, there has been a relatively small amount of research on how citizen participation influences the direction and content of technological innovation. Also, although, from the viewpoint of technological innovation, how participation of citizens in science and technology can contribute to knowledge production and innovation is a critical issue, relatively small numbers of case studies on this subject have been conducted. Therefore, as the scholars who have emphasized the democracy of science and technology have actually experimented with various ways of citizen participation, innovation researchers may have to design and implement citizen participation through which citizens' local knowledge can contribute to technological innovation.

• Radiation Oncology Journal
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• v.19 no.1
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• pp.74-80
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• 2001

Purpose : Irradiation cones by using backscatter electrons are made for the treatment of superficial small lesions of skin, oral cavity, and rectum where a significant dose gradient and maximum surface dose is desired. Methods and Materials : Backscatter electrons are produced from the primary electron beams from the linear accelerators. The design consists of a cylindrical cone that has a thick circular plate of high atomic number medium (Pb or Cu) attached to the distal end, and the plate can be adjusted the reflected angle. Primary electrons strike the metal plate perpendicularly and produce backscatter electrons that reflect through the lateral hole for treatment. Using film and a parallel plate ion chamber, backscatter electron dose characteristics are measured. Results : The depth dose characteristic of the backscatter electron is very similar to that of the hard x-ray beam that is commonly used for the intracavitary and superficial lesions. The basckscatter electron energy is nearly constant and effectively about 1.5 MeV from the clinical megavoltage beams. The backscatter electron dose rate of $35\~85\;cGy/min$ could be achieved from modern accelerators without any modification. and the depth in water of $50\%$ depth dose from backscatter electron located at 6mm for $45^{\circ}$ angled lead scatter. The beam flatness is dependent on the slit size and the depth of treatment, but is satisfactory to treat small lesions. Conclusions : The measured data for backscatter electron energy, depth dose flatness dose rate and absolute dose indicates that the backscatter electrons are suitable for clinical use.

• Journal of Sasang Constitutional Medicine
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• v.19 no.2
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• pp.40-52
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• 2007

1. Objectives and Methods The purpose of this study was to objectify the diagnosis of Sasang Constitution. 63 Male Juvenile's and 151 Female Juvenile's sentences were analyzed into 73 factors like Pitch, APQ, Shimmer, Octave and Energy, etc. Juvenile's sentences were classified into 6 categories: total Male Juvenile group, under 12 years old Male Juvenile grout, over 13 years old Male Juvenile group, total Female Juvenile group, under 12 years old Female Juvenile group and over 13 years old Female Juvenile group. 2. Results 1) In Total Male Juvenile group, there were no significant differences among constitutional groups in APQ and Octave segment. Taeumin's Center freq.(3) was significantly high compared with Soyangin group. Soeumin's Center freq.(5) was significantly high compared with Soyangin and Taeumin groups. Taeumin's Octave3 Shimmer was significantly high compared with Soeumin group. Soeumin's Octave6 Shimmer was significantly high compared with Taeumin group. Solyangin's D# Tot E was significantly high compared with Taeumin group. 2) In Under 12 years old Male Juvenile group, there were on significantly among constitutional groups in Pitch, APQ, Octave and Energy segment. Taeumin's Octave3 Shimmer and G Shimmer(1) were significantly high compared with Soeumin group. 3) In Over 13 years old Male Juvenile group, there were no signigicant differences among constitutional groups in Pitch, APQ and Shimmer segment. Soyangin's and Soeumin's Octave6 were significantly high compared with Taeumin group. Soyangin's $0k{\sim}2k$ Total Sum, $0k{\sim}2k$ Dev., $2k{\sim}4k$ Total Sum, $2k{\sim}4k$ Dev., A Dev.(1), D# Dev.(1) and G# Dev.(1) were significantly high compared with Taeumin group. Soyangin's and Soeumin's G# Tot E were significantly high compared with Taeumin group. 4) In Total Female Juvenile group, there were no significant differences among constitutional groups in Pitch and APQ segment. Soeumin's Octave4 Shimmer was significantly high compared with Soyangin group. Soyangin's Octave6 was significantly high compared with Soeumin group. Solyangin's 2k-4k Total Sum and B Tot E were significantly high compared with Soeumin group. 5) In Under 12 years old Female Juvenile group, there were no significant differences among constitutional groups in APQ and Energy segment. Soeumin's and Taeumin's Center Pitch and Pitch were significantly high compared with Soyangin group. Soyangin's Center freq.(1) and Center freq.(7) were significantly high compared with Soeumin and Taeeunin groups. Soyangin's and Taeumin's B Shimmer(1) and F# Shimmer(1) were significantly high compared with Soeumin group. Soeumin's D Shimmer(1) was significantly high compared with Soyangin group. Taeumin's and Soeumin's G# Shimmer(1) were significantly high compared with Soyangin group. Soyangin's and Taeumin's Octave2 were significantly high compared with Soeumin group. 6) In Over 13 years old Female Juvenile group, there were no significant differences among constitutional groups in Pitch, APQ and Octave segment. Soeumin's Octave4 Shimmer was significantly high compared with Soyangin group. Soyangin's B Dev.(1) and F Dev.(1) were significantly high compared with Soeumin group. 3. Conclusions In juvenile groups, some sound factors are regarded as useful. PSSC are thought to be the objertive way to diagnose the Consitution and more participants are needed to get more efficiencies using PSSC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1386-1396
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• 2017

The purpose of this study was to determine the optimum Platycodon grandiflorum root concentrate (PGRC, $65^{\circ}Brix$), fermented P. grandiflorum root extract by Lactobacillus plantarum (FPGRE, $2^{\circ}Brix$), and cactus Chounnyouncho extract (Cactus-E, $2^{\circ}Brix$) for preparation of PGRC stick product with FPGRE using response surface methodology (RSM). The experimental conditions were designed according to a central composite design with 20 experimental points, including three replicates for three independent variables such as amount of PGRC (8~12 g), FPGRE (0~20 g), and Cactus-E (0~20 g). The experimental data for the sensory evaluation and functional properties based on antioxidant activity and antimicrobial activity were fitted with the quadratic model, and accuracy of equations was analyzed by ANOVA. For the responses, sensory and functional properties showed significant correlation with contents of three independent variables. The results indicate that addition of PGRC contributed to increased bitterness and acridity based on the sensory test and antimicrobial activity, addition of FPGRE contributed to increased antioxidant activity and antimicrobial activity, and addition of Cactus-E contributed to increased fluidity based on the sensory test, antioxidant activity, and antimicrobial activity. Based on the results of RSM, the optimum formulation of PGRC stick product was calculated as PGRC 8.456 g, FPGRE 20.00 g, and Cactus-Ex 20.00 g with minimal bitterness and acridity, as well as optimized fluidity, antioxidant activity, and antimicrobial activity.

• Health Policy and Management
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• v.34 no.3
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• pp.334-346
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• 2024

Background: Research on the link between subjective health and unmet healthcare needs is limited. This study examines whether experiences of subjective healthcare needs and unmet needs are related to subjective health in South Korea, where the rate of poor subjective health is notably high. Methods: This analysis utilized data from the Korea Health Panel (2014-2018), incorporating 68,930 observations from 16,535 adults aged 19 or older. The dependent variable, subjective health, was dichotomized into poor (bad or very bad) and non-poor (fair, good, or very good) categories. The primary variables of interest were the experiences of subjective healthcare needs and unmet needs, while control variables included 14 socio-demographic, health, and functional characteristics. The study employed population proportion analysis and multivariable two-level binary logistic regression analysis for each gender, accounting for the complex sampling design. Results: In 2018, the rate of reporting poor health was 8.7% (95% confidence interval [CI], 8.0%-9.5%) for men and 14.7% (95% CI, 13.8%-15.6%) for women. For both genders, compared to individuals whose healthcare needs were met, those without healthcare needs were less likely to report poor subjective health (adjusted odds ratio [AOR], 0.58; 95% CI, 0.39-0.86 for men; AOR, 0.59; 95% CI, 0.37-0.93 for women). Conversely, individuals whose healthcare needs were not met were more likely to report poor subjective health (AOR, 2.31; 95% CI, 2.01-2.65 for men; AOR, 2.19; 95% CI, 1.98-2.43 for women). A policy simulation indicated that reducing the experience of subjective healthcare needs would be approximately 5 times more effective in reducing poor subjective health than a policy focused on reducing the experience of unmet needs. Conclusion: South Korea must make significant efforts to reduce the deterioration of subjective health and promote appropriate healthcare utilization. To achieve this, a set of policies is recommended to address subjective healthcare needs. These policies should include (1) prompting individuals to proactively manage their own health, (2) providing primary healthcare similar to that in advanced countries, (3) ensuring the healthcare delivery system operates effectively, (4) decentralizing the healthcare management system, and (5) reducing the likelihood of people being misled into thinking they have a healthcare need.

• Journal of The Korean Association For Science Education
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• v.40 no.3
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• pp.337-346
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• 2020

In this study, we investigated the characteristics of students participating in Science Core high schools classes and their relevance to Positive Experiences on Science (hereinafter, PES), and factors causing PES, presented by the students of Science Core high schools. A total of 20 students and five teachers in four regions across the country participated in the in-depth interview, which were conducted with the focus group of students first, and then in-depth interviews with teachers. Based on the interview results, we explored teaching and learning experiences helpful to the PES, assessment experiences resulting in the PES, and ways to support Science Core high schools to enhance their PES. Students and teachers of Science Core high schools argued that students' participation will increase only if they engage in classes while drawing attention within the range that students can understand, students' PES such as scientific interest can be improved through experiments in which students choose topics or design their own exploration process, science competencies such as science problem solving ability and scientific thinking ability should be developed through exploratory experiment activities that fit the nature of science, etc. In addition, regarding ways to improve and support Science Core high schools to enhance PES, securing science class hours, restructuring the contents of science elective courses, and necessity of maintaining Science Core high schools are suggested. Based on the research results of science high school students' PES, ways to improve the PES of general high school students are discussed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.4
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• pp.350-356
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• 2016

The objective of this study was to evaluate the effect of different dietary corn levels in Total Mixed Rations (TMR) on growth and meat quality of castrated Korean black goats. For feeding trials, thirty-two castrated Korean black goats with similar age (average of 3 months) and body weight (average of 15.9 kg) were divided into the following four treatment groups: commercial feed (control), TMR containing 15% of corn (T1), TMR containing 25% of corn (T2), and TMR containing 35% of corn (T3) in a randomized complete block design. Final body weight was the highest in T2 (58.9 kg), followed by that in control group (53.1 kg). Average daily gain (ADG) and total dry matter intake (TDMI) were also the highest in T2 (100.2 g and 1,346 g, respectively). However, feed conversion ratio (13.4) was the lowest in T2. Carcass weight and dressing percentage in T2 and T3 were higher than those in the control. For meat quality characteristics, crude fat content was the highest in T2 (6.54%). Cooking loss (15.2%) was the lowest in the control. However, the control had the highest flavor value (5.3%). Oleic acid (C18:l) and palmitic acid (C16:0) were the highest in T2 (48.6% and 22.4%, respectively). Stearic acid (C18:0) was the highest in T1 (14.5%). Unsaturated fatty acid was the highest in the control (58.8%), followed by that in T3 (58.2%), T2 (57.8%), and T1 (54.4%). These results indicate that TMR containing 25% of corn could improve the growth performance and meat quality of castrated Korean black goats.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.101-115
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• 2018

This study was carried out to evaluate the effects of various filter conditions on unconfined aquifer (alluvial aquifer). We made model test device which has filter layer, pumping well and observation well which consist of sand layer and gravel layer to test. Step drawdown test and long term pumping tests were carried out using the device. The permeability characteristics of each test group were confirmed and the optimal yield was calculated. As a result of comparing the optimal yield of double filter and single filter in sand, dual-filter SD-300 was valued at 216.8 % higher final optimal yield than single-filter SS-300. Comparing the dual filter SD-300 and the single filter SS-100 with a thin filter layer, dual-filter SD-300 was valued at 709.2% higher final optimal yield than single-filter SS-300. As a result of analysis of optimal yield change over time, It was confirmed that the ratio of optimal yield of single filter and dual filter increase over time. In order to evaluate the long-term change in water intake efficiency, we considered the point at which the initial optimal yield was reduced by 50%. The dual filter SD-300 is about 351.1% higher than SS-300, which is the same thickness filter, and about 579.0% higher than SS-100. From these results, Assuming that the point at which the initial quantity of water intake is reduced to 50% is the well life, double filters are expected to increase their lifespan by about 3.5 times over single filters of the same thickness and by about 5.8 times over typical single filter. These results can be used to design wells to river bank filtration or filtered seawater. In addition, it is possible to clarify the effect of the double filter through the comparison with the future field test results.