• Journal of the Economic Geographical Society of Korea
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• v.25 no.4
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• pp.469-483
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• 2022

This paper aims to examine how and why the role of Seoul National University has evolved through the formation of Seoul National University's entrepreneurial ecosystems (SNUEEs). To identify this, we used secondary data on SNU entrepreneurship and did in-depth interviews with 17 student entrepreneurs and supportive actors in the ecosystems. First, the university-industry cooperation policy and the first start-up boom in the late 1990s gave rise to the first generation of SNUEEs. They entered the second generation with the second start-up boom in 2010. The third generation emerged through the government's start-up support policy and the venture investment market revitalization in 2017. Second, SNUEEs have experienced transformations of the university's role from an 'ivory tower' to a 'feeder of knowledge and labor' and have become a 'hub of knowledge networks.' Third, hub institutions and organizations were established and supported by government policies, and networks of SNUEEs have been embedded in these hub institutions and organizations. SNUEEs as a hub university are evolving through the formation of a voluntary entrepreneurial culture by student entrepreneurs, the supportive policy at the university level, and the establishment of linkages with the region where the university is located.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.2
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• pp.73-81
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• 2007

We give two weaknesses of a recently proposed streamcipher MICKEY. We show time-memory-data tradeoff is applicable. We also show that the state update function reduces entropy of the internal state as it is iterated, resulting in keystreams that start out differently but become merged together towards the end.

• The Journal of Korea Robotics Society
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• v.17 no.3
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• pp.314-321
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• 2022

Depth information used in SLAM and visual odometry is essential in robotics. Depth information often obtained from sensors or learned by networks. While learning-based methods have gained popularity, they are mostly limited to RGB images. However, the limitation of RGB images occurs in visually derailed environments. Thermal cameras are in the spotlight as a way to solve these problems. Unlike RGB images, thermal images reliably perceive the environment regardless of the illumination variance but show lacking contrast and texture. This low contrast in the thermal image prohibits an algorithm from effectively learning the underlying scene details. To tackle these challenges, we propose multi-channel remapping for contrast. Our method allows a learning-based depth prediction model to have an accurate depth prediction even in low light conditions. We validate the feasibility and show that our multi-channel remapping method outperforms the existing methods both visually and quantitatively over our dataset.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.1
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• pp.41-46
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• 2022

To investigate the domestic seed production potential of Italian ryegrass, it was sown in autumn in the southern region and harvested in the spring of the following year to investigate the productivity and quality of seeds and straw. Italian ryegrass (Lolium multiflorum Lam.) 'GreenCall' variety was sown in Jinju, Gyeongnam in the fall of 2020 with three seeding rates (20, 30 and 40 kg/ha). The experiment was arranged consisted of a randomized block design with three replications. The ryegrass was sown on October 17, 2020, and the harvest was on May 31, about 60 days from the heading stage. The heading stage of Italian ryegrass was April 28, and there was no difference among treatments. Plant height was significantly shorter in the 40 kg/ha seeding treatment group, and there was no significant difference in the remaining treatments. The resistance of lodging, disease, and cold did not show significant differences among treatments. Spike length and number of seeds per spike were highest at 20 kg/ha seeding amount, and there was no difference in the remaining treatments. The seed yield was the highest at 1,956 kg/ha in the 20 kg/ha seeding rate, and there was no difference in the 30 and 40 kg/ha seeding rates. The dry matter content of seeds and straws was 45.60 and 41.83% on average, and there was no significant difference among treatments. The amount of remaining straw after seed harvesting was found to be 7,689 kg/ha on average on a dry basis, and it was high in the 40 kg/ha sowing area, but there was no significant difference among treatments. According to the above results, it was found that it is most advantageous to sow at 20 kg/ha when producing Italian ryegrass seeds through autumn sowing in the southern region.

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.287-290
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• 2001

The 9.17MeV gamma-rays from the $^{13}C(p,\;{\gamma})^{14}N,\;^{14}N({\gamma},\;{\gamma})^{14}N$ reactions were measured. The incident 9.17MeV gamma-ray was produced from the $^{13}C(p,\;{\gamma})^{14}N$ reaction at Ep=1.75MeV resonance. The 1.75MeV proton beam was accelerated using the 3MV SNU-AMS Tandetron and 1.7MV KIGAM Tandem accelerators. The enriched 13C target was $121{\mu}g/cm^2$ self-supporting foil, and we used liquid nitrogen as a resonant absorption target. We used a HP-Ge detector with 30% efficiency and less 2keV energy resolution. We developed new method to detect the scattered 9.17MeV gamma-ray from the nitrogen target by using the energy difference between the Doppler shifted gamma-ray from the $^{13}C(p,\;{\gamma})^{14}N$ reaction and the resonant absorbed and rescattered gamma-ray from the $^{14}N({\gamma},\;{\gamma})^{14}N$ reaction.

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.403-409
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• 2008

Elaeagnus multiflora, generally referred to as the cherry silverberry, is a plant. Elaeagnus multiflora fruit, leaves, and roots have been traditionally utilized in China as a treatment for cough, diarrhea, itch, and foul sores, and even cancer. More importantly, it is being investigated as a food that is capable of reducing the incidence of cancer, and also as a means of halting or reversing the growth of cancers. Considering the dearth of information regarding the medicinal properties of Elaeagnus multiflora, we assessed the antioxidative and cytotoxic effects of Elaeagnus multiflora by examining its scavenging effects on the 1,1-diphenyl-2-picryl-hydrazyl(DPPH) radical, its inhibitory effects on lipid peroxidation, and its inhibitory effects on cancer cell proliferation in HeLa cells, MCF-7 cells, and SNU-638 cells via MTT assay. Ethanol extracts of Elaeagnus multiflora flesh and seed inhibited DPPH radical production($36.91{\pm}1.00$, $94.17{\pm}0.37$) and lipid peroxidation ($28.18{\pm}5.02$, $40.30{\pm}1.45$, respectively). The Elaeagnus multiflora seed is believed to exert a possible antioxidative effects against the DPPH radical. The ethanol extracts of Elaeagnus multiflora flesh and seed exerted the cytotoxic effects on Hela cells ($6.93{\pm}1.92$, $84.97{\pm}0.47$), MCF-7 cells($5.45{\pm}0.41$, $84.97{\pm}0.47$), and SNU-638 cells($19.39{\pm}0.43$, $76.84{\pm}0.63$) used in this study. This result suggests that Elaeagnus multiflora seeds in contrast to its flesh, is believed to exert a possible anticancer effect. Elaeagnus multiflora seeds are considered to be a the candidate for preventative and dietetic treatment as an anticancer functional food.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.2
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• pp.221-237
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• 1991

This study was conducted to evaluate the accuracy and the precision of asbestos counting data produced by the Division of Industrial Health, School of Public Health, Seoul National Universitys (SNU). The study was performed from July 18 to October 4, 1991, and the results are summarized as follows. 1. Intracounter Relative Standard Deviations (Sr) in the category of 5-50.5 fibers as total fibers counted ranged from 0.27 to 0.37, which were greater than 0.10-0.17 which were reported by the NIOSH. The reasons are supposed to be as follows. First, inexperience of counters in asbestos fiber counting was considered to be a main reason. Second, poor quality of samples due to sampling and mounting error increased variation of counting. Third, fiber density of many samples were less than $100fibers/mm^2$. But Intracounter Relative Standard Deviations (Sr) in samples with >50.5 fibers ranged from 0.l6 to 0.20, approaching the value 01 NIOSH. 2. Intralaboratory Relative Standard Deviations (Sr) in categories of 5-20.5, >20.5-50.5 and >50.5 fibers were 0.54, 0.37 and 0.26, respectively. Intralaboratory Sr in samples with fiber density greater than $100fibers/mm^2$ was 0.26. This was similar to the values reported by other foreign experienced laboratories. 3. Comparing results of three counters, Counter C, a beginner, overestimated asbestos fiber concentrations. 4. Since our SNU laboratory has participated in two quality control programs, IOMA-F.R.I.C.A., U.K. and NIOSH PAT Program, U.S.A., this laboratory has been evaluated as " Rating 1" and "Proficient" laboratory, by IOM and NIOSH, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.1
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• pp.55-60
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• 2000

This experiment was carried out to determine the effect of cutting frequency(3rd and 5th cut) and level of nitrogen fertilization(l50 + liquid manure, 300 and 450kgha) on growth characteristics, dry matter yield and nutritive vaule of reed canarygrass(Pha1aris arundinacea L.), at the forage experimental field, College of Agriculture and Life Sciences, SNU, Suweon. Plant height of 3rd cutting(79.2cm) was significantly higher than that of 5th cutting(58.0cm). And dry mattter yield of cutting frequency was observed in 3rd cutting(16,902kgPna) and 5th cutting(l7,833kg/ha) As the nitrogen fertilization was increased, DM yield was significantly increased(p<0.05). When the nitrogen fertilization was applied at the level 150 + liquid manure, 300 and 450kg, dry matter yields were 16,5 12, 17,123 and 18,368kg/ha, respectively. The contents of neutral detergent fiber(NDF), acid detergent fiber(ADF) and in vitro dry matter digestibility(1VDMD) were similar among cutting frequency. However, slightly higher NDF, ADF and IVDMD contents were found in 5th cutting, but there was not affected by nitrigen fertilization. Based on the results of this experiment, it were indicated that to 5th cutting and 450kg nitrogen fertilization could be obtained from the increase of dry matter yield and nutritive value (Key words : Cutting frequency, Nitrogen fertilization, Dry matter yield, Nutritive Value, Reed canarygrass)

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.3
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• pp.201-207
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• 2017

Hay-making is one of the most common forage preservation practices in livestock operations. The objective of hay-making is to minimize nutrient loss by shortening field drying time. Measuring the impacts of cutting height of forage crop is necessary to optimize hay production balancing yield and quality, in order to obtain substantial biomass increase through harvest of regrowth. This experiment was conducted to investigate the impact of cutting height of rye (Secale cereale L.) on drying rate and hay quality. Heading stage rye was harvested at 8cm or 15cm stubble heights. Hay was daily tedded at 09:00 and sampled at 09:00, 13:00 and 17:00 to determine moisture content (MC). After two month of preservation, CP (crude protein), ADF (acid detergent fiber), NDF (neutral detergent fiber), IVDMD (in vitro dry matter disappearance), TDN (total digestible nutrient), RFV (relative feed value), DM (dry matter) loss, visual scores and total fungi count were determined for estimation of hay quality. Cutting height at 15cm could enhance the drying rate and CP content (p<0.05), but also increases DM loss (p<0.05) compared to cutting at 8cm. Cutting heights did not affect ADF, NDF, IVDMD, TDN and RFV value (p>0.05). Visual scores of rye hays cutting at 8cm and 15cm, ranged from 83 to 85. Cutting at 8cm tended to maintain higher core bale temperature and fungal count than cutting at 15cm during preservation, but there was no significant difference.

• Clinical and Experimental Otorhinolaryngology
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• v.11 no.4
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• pp.242-249
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• 2018

Objectives. Smoking is associated with hearing loss, while the correlation between tinnitus and smoking is not fully elucidated. This study aimed to evaluate risk factors of tinnitus in adolescents in terms of smoking, and we identified a rectifiable parameter that can be serially monitored. Methods. A cross-sectional study was conducted using data from the Korea National Health and Nutrition Examination Survey, with 2,782 participants aged 12 to 18 years, from 2008 through 2011. Participants with history of ear disease, hearing loss, and inadequate responses to questionnaires were excluded. We investigated the prevalence of tinnitus and tinnitus-related annoyance by questionnaire and sought potential risk factors in blood and urine tests and smoking history. Results. The prevalence of tinnitus in the 12- to 18-year-old population was 17.5%, with 3.3% reporting tinnitus-related annoyance. On univariate analysis, the prevalence of tinnitus increased with age (P<0.001) and was higher among girls (P=0.012). Blood tests and urinalysis showed significant correlation between tinnitus and red blood cell count, alkaline phosphatase levels, and urine cotinine (P=0.002, P<0.001, P=0.018, respectively). In multivariate analysis, the urine cotinine level was the only parameter associated with tinnitus (odds ratio, 1.000; 95% confidence interval, 0.999 to 1.000; P=0.038). Smoking was also significantly correlated with tinnitus (P=0.043), and amount of smoking with tinnitus-related annoyance (P=0.045). However, current smoking and past smoking were not correlated with tinnitus. Conclusion. Urine cotinine may be a rectifiable marker for management of tinnitus in adolescents. This suggests that smoking cessation should be incorporated in the management of tinnitus in adolescents.