• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.10
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• pp.796-804
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• 2013

The "Potato Gun," a simple heat engine, is fabricated, tested and analyzed as a part of engineering education program of combustion and propulsion classes. Combustor pressure is predicted by the chemical equilibrium analysis of a constant volume combustor. Then, the internal ballistics, the conversion of thermal energy into the mechanical energy of a projectile, is predicted though the expansion process. The trajectory of a projectile is estimated by considering the aerodynamic effect around the spherical projectile. The energy conversion efficiency and the equivalence ratio of the fuel-air mixture could be estimated by the comparison of the experimental results and the theoretical prediction. The present work would be an example of attracting the interest of students for the application of the engineering principles at undergraduate level by recycling the waste materials.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.4 no.9
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• pp.19-27
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• 1983

감자는 세계적으로 중요한 식량 작물의 하나로서 총 생산량은 어느 작물보다 높아 날로 늘어만 가는 세계 인구에 대한 식량으로는 더할 수 없이 훌륭한 작물로 각광받기 시작하기에 이르렀다고 할 수 있다. 이렇게 중요한 작물인 감자에 병을 일으키는 바이러스는 세계적으로 25여종으로 보고된바 있으며 이들 바이러스에 의한 병리적 퇴화는 오래전부터 감자의 수량을 감수시키는 가장 큰 장해요인으로 지적되어 왔다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.144-145
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• 2003

감자는 전세계 대부분의 국가에서 재배되고 있는 세계 4대 주곡 작물인 동시에 스낵류 시장에서도 중요한 부분을 차지하고 있다. 우리나라의 감자 가공산업은 1990년대 초부터 활기를 띠기 시작여하 현재 2,000억불의 매출을 달성하고 있다. 이중 우리나라 농민이 직접 생산한 감자를 원료로 사용하는 천연칩 감자 가공산업은 매출액을 기준으로 144억 (1997년)에서 700억 (2001년)으로 과거 10년 동안 괄목할 만한 성장을 하였다. 우리나라의 연간 감자 칩 원료용 가공용 감자 소요량은 총 51,600톤 (2002 년)으로 그중 40,600톤은 국내생산량으로 충당하고 나머지는 냉동감자를 수입하여 처리하고 있다. 가공원료용 감자는 괴경의 크기나 모양과 같은 외부품질과 환원당이나 고형분 함량과 같은 내부품질이 좋아야 한다. 하지만 가공용 감자의 내·외부품질이 좋게 판정되어도 내부갈색반점이나 중심공동과 같은 괴경 생리장해가 발생하면 원료용 감자로서의 상품 가치가 상실된다. 국내 칩 가공원료용 감자는 봄재배에서는 약 5 ∼ 7 ％, 여름재배에서는 10 ∼ 15 ％의 괴경 생리장해가 발생되고 있다. 현재 위와 같은 생리장해는 가공공장에서 감자를 잘라서 골라내거나 감자 칩을 만든 후 제거하는 방법을 쓰고 있다. 이에 감자를 수확 후 감자칩으로 가공하기 전에 생리장해가 발생한 감자를 제거하여 생산 공정에서의 불필요한 가공을 줄일 수 있는 방법이 개발되어야 할 필요성이 증대되고 있다. 최근, 농산물의 비파괴적 품질 평가와 선별에 있어서 가장 실용적이고 성공적인 기술 중의 하나는 농산물의 광학적 성질을 이용한 전기-광학 기술이다. 그중 X-선과 같이 파장이 짧은 방사 에너지는 대부분의 농산물을 투과하여 내부의 질량 밀도의 변화와 상관관계를 갖는 품질 인자를 비파괴적으로 평가하는데 적합하나 아직 국내에선 X-선을 이용한 가공용 감자의 내부 결함특성에 대한 연구는 이뤄지지 않고 있다. 이에 본 연구에서는 가공용 감자의 내부결함 특성중 하나인 내부동공의 X-선에 의한 특성을 본 연구소에 있는 X-선 발생장비로 측정해 보고 비파괴적인 방법으로 실시간 가능성을 시험하였다. 감자는 수원 농산물 도매시장에서 2003년산 가공용 감자 (품종:선농)를 구매하여 사용하였다. 감자내 내부동공은 35 ∼ 40 kV와 5.25 mA값으로 발생된 X-선에 의해 잘 검출되는 것으로 나타나, 현장에서 충분히 활용가능 할 것으로 판단되었다. 금후, 실시간으로 내부동공을 검출할 수 있는 시스템을 개발할 계획이다.

• Culinary science and hospitality research
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• v.20 no.3
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• pp.80-89
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• 2014

This study examined the nutritional components and physicochemical properties of small colored potatoes and small regular potatoes as a natural health food source. To accomplish this, the general and antioxidative contents of small colored potatoes and small regular potatoes were measured. Total contents of carbohydrates, crude protein, crude lipid, and ash were 88.1%, 4.9%, 0.9%, and 6.4%, respectively. Small colored potatoes contained 76.5 kcal, while their total dietary fiber was 4.0%. Total proteins consisted of 17 different kinds of amino acids. Regarding their mineral contents, K was the most abundant mineral, followed by P, Mg, and Ca. Total phenol contents of the 70% ethanolic extracts of small colored potatoes were $48.2{\pm}1.2$ mg GAE/g. Total flavonoid contents of the 70% ethanolic extracts were $13.1{\pm}0.3$ mg RE/g. Overall, small colored potatoes had higher amounts of nutrients and physicochemical properties than small regular potatoes. The general nutrients and other antioxidant bioactive materials in small colored potatoes were also potential materials for good health food. It is expected that follow up studies of small colored potatoes through developing processed food and evaluation of their functional properties would provide useful information as a source of functional foods.

• Journal of Plant Biotechnology
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• v.49 no.3
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• pp.178-186
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• 2022

The tetraploid Solanum acaule is a wild potato species from Bolivia widely used for potato breeding because of its diverse attractive traits, including resistance to frost, late blight, potato virus X, potato virus Y, potato leafroll virus, potato spindle tuber viroid, and cyst nematode. However, the introgression of useful traits into cultivated potatoes via crossing has been limited by differences in endosperm balance number between species. Somatic fusion could be used to overcome sexual reproduction barriers and the development of molecular markers is essential to select proper fusion products. The chloroplast genome of S. acaule was sequenced using next-generation sequencing technology and specific markers for S. acaule were developed by comparing the obtained sequence with those of seven other Solanum species. The total length of the chloroplast genome is 155,570 bp, and 158 genes were annotated. Structure and gene content were very similar to other Solanum species and maximum likelihood phylogenetic analysis with 12 other species belonging to the Solanaceae family revealed that S. acaule is very closely related to other Solanum species. Sequence alignment with the chloroplast genome of seven other Solanum species revealed four InDels and 79 SNPs specific to S. acaule. Based on these InDel and SNP regions, one SCAR marker and one CAPS marker were developed to discriminate S. acaule from other Solanum species. These results will aid in exploring evolutionary aspects of Solanum species and accelerating potato breeding using S. acaule.

• Korean journal of food and cookery science
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• v.10 no.1
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• pp.24-28
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• 1994

The effects of synthetic and carrot carotene on the browning of polyphenolics extracted from potato for eliminating the effects of other components in potato which inhibit the browning of potato juice and the potato polyphenol oxidase (PPO) activity were investigated. Total phenolics content in potato sample was 1.854mg/g D.W. and PPO activity was 100 unit. Delta 'L'value of polyphenolics extracted from potato decreased makedly, but that of potato with carrot decreased little by little. Potato with P-carotene showed a little decrease after 50 min. At the same time, polyphenolics extracted from potato were mixed with carotene extracted from carrot or with syntetic $\beta$-carotene. As the results, the delta 'L'value of the former increased but decreased similarly to the latter after 1 hour. The effects of enzyme and substrate concentration on the browning of PPO extracted from potato were investigated. Optimum enzyme concentration was 10% and optimum substrate concentration was 13.3% $\beta$-carotene concentration did not appear to influence significantly on PPO activity.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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• pp.607-613
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• 2004

The purpose of this study was to investigate the quality characteristics of functional cookies made with potato peels (cortex layer) containing high amounts of glycoalkaloid. Cookies were processed by mixing ratios of 10, 15 and $20\%$ potato peel relatively to flour. The spread ratio of the cookies was increased with increasing potato peel addition. Texture measurement for the cookies on substituting $10\%$ of flour for potato peel showed a decreased hardness, but the cohesiveness and springiness were increased compared to the control and other ratios. The glycoalkaloid contents of the cookies on substituting 10, 15 and $20\%$ of the flour forpotato peel were 6.27, 9.40 and 12.54mg, respectively, which according to the USAD guidelines are safe amounts for the human body, and also enough for making functional cookies. In the sensory evaluations, the cookies with $10\%$ of the flour substituted for potato peel had the highest scores in flavor, taste, appearance and texture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.8
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• pp.1035-1040
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• 2012

This study was aimed to evaluate and compare the biological activities and total phenolic content of ethanol extracts of white (Superior) and colored potatoes (Red, Rose, Haryoung, Blue, Jaseo, and Jasim). Various ethanol extracts (250, 500, 1,000, and $2,000{\mu}g/mL$) were assessed for antioxidant activities of DPPH free radicals and hydroxyl radical scavenging. The cytotoxic activity of the extracts (0, 30, 60, $100{\mu}g/mL$) was also carried out by a human cancer cell lethality bioassay method. Results showed that the DPPH and hydroxyl radical scavenging activities, of all extracts increase in a concentration-dependant manner. All color-fleshed potato extracts, except for Red and Haryoung, showed higher radical scavenging activities than the general white potato extract. Cytotoxicity of the extracts as determined in THP-1 cells showed that Blue and Jasim was highly toxic at most concentrations tested. In addition, the Blue extract had the highest cytotoxic activity on $HepG_2$ cells at the concentration $100{\mu}g/mL$. The contents of total phenolic (TPC) in the extracts significantly varied from 120.0 mg/100 g powder (Superior) to 151.1 mg/100 g powder (Blue), and TPC of all color-fleshed potato extracts was higher than that of white. The greatest positive correlation was found between phenolic contents and hydroxyl radical scavenging activity (r=0.776, p<0.05), and a strong negative correlation was found between hydroxyl radical scavenging activity and cytotoxic activities on $HepG_2$ cells (r=-0.795, p<0.05). The present study demonstrates that color-fleshed potatoes have higher antioxidant and stronger anticancer activities than general potato. These results provide useful and important information for potato breeders and researchers, in order to increase the antioxidant capacity and functional value of colored potatoes for use in the food and pharmaceutical industries.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.663-668
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• 2007

This study evaluated the microbial, nutritional, and rheological changes in potatoes, during storage at room, low, and freezing temperatures for 6 months. No significant changes in total aerobic plate counts were observed for any of the samples in the assessment of microbiological quality changes. For the 4 types of frozen potatoes, yeasts and molds were not found until 24 weeks. The sugar contents of the potatoes stored at room and low temperature ($10^{\circ}C$) increased during the first 4 weeks of storage, but then decreased rapidly thereafter; while those in the frozen potatoes did not change significantly throughout the 48 weeks. The vitamin C, B1, and B2 contents of the potatoes stored at room and low temperature had decreased significantly after 4 weeks of storage, however, the levels in the frozen potatoes did not change rapidly. The weight, volume, and hardness of the frozen potatoes changed much less as compared to the potatoes stored at room and low temperature over the 48 weeks of storage. Finally, the cohesiveness of all the samples, except for the frozen mashed potatoes, did not change during storage.

• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.358-362
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• 1996

감자 잎말림 바이러스를 검정하기 위하여 ELISA 및 전자현미경에 의해 바이러스 감염이 확인된 기내 배양중인 감장의 줄기로부터 RT-PCR 분석을 수행하였다. 분리된 총 RNA들로부터 바이러스 cDNA를 합성하고 감자 잎말림 바이러스 외피단백질의 일부인 465bp를 특이하게 증폭하도록 고안한 두 primer를 사용하여 PCR 반응을 하였다. 증폭된 465pb의 DNA 절편의 염기서열을 분석한 결과 역시 감자 잎말림 바이러스임을 확인하였다. 바이러스 검정에 있어서 EL-ISA 방법과 RT-PCR 방법간의 민감도를 조사한 결과 RT-PCR 방법간의 민감도를 조사한 결과 RT-PCR 방법이 ELISA 방법보다 감자 잎말림 바이러스검정에 있어서보다 정확한 방법인 것으로 사료된다.