• Title/Summary/Keyword: 2b

Search Result 52,062, Processing Time 0.09 seconds

Methods of Incorporating Design for Production Considerations into Concept Design Investigations (개념설계 단계에서 총 건조비를 최소로 하는 생산지향적 설계 적용 방법)

  • H.S.,Bong
    • Bulletin of the Society of Naval Architects of Korea
    • /
    • v.27 no.3
    • /
    • pp.131-136
    • /
    • 1990
  • 여러해 전부터 선박의 생산실적이나 생산성 관련 자료를 기록하고 보완하는 작업을 꾸준히 개선토록 노력해온 결과중 중요한 것 하나는, 선박의 여러 가지 설계 검토과정에서 충분히 활용할 수 있는 함축성 있고 믿을만한 형태의 생산정보를 제공해줄 수 있게 되었다는 것이라고 말 할 수 있겠다. 이러한 자료들은 생산계획상 각 단계(stage)에서의 작업량, 예상재료비와 인건비의 산출등이 포함될 수 있으며, 선박이나 해상구조물의 전반적인 설계방법론(design methodology)을 개선코자 한다면 ''생산지향적 설계(Design for Production)''의 근간이 되는 선박건조전략(build strategy), 구매정책(purchasing policy)과 생산기술(production technology)에 대한 폭넓은 지식이 한데 어우러져야 한다. 최근에는 CIMS의 일부분에서 보는 바와 같은 경영관리, 설계 및 생산지원 시스템의 도입으로 이와 같은 설계 프로세스의 추진을 가능케하고 있다. 이와 병행하여 설계를 지원하기 위한 전산기술, 특히 대화형 화상처리기술(interactive graphics)의 발달은 설계자가 선박의 형상이나 구조 배치를 여러 가지로 변화시켜 가면서 눈으로 즉시 확인할 수 있도록 설계자의 능력을 배가시키는데 크게 기여하고 있다. 여러 가지의 설계안(alternative design arrangement)을 신속히 만들어내고 이를 즉시 검토 평가할 수 있는 능력을 초기설계 단계에서 가질 수 있다면 이는 분명히 큰 장점일 것이며, 더구나 설계초기 단계에 생산관련인자를 설계에서 고려할 수 있다면 이는 더욱 두드러진 발전일 것이다. 생산공법과 관련생산 비용을 정확히 반영한 각 가지의 설계안을 짧은 시간내에 검토하고 생산소요 비용을 산출하여 비교함으로써, 수주계약단계에서 실제적인 생산공법과 신뢰성있는 생산실적자료를 기준으로 하여 총 건조비(total production cost)를 최소로 하는 최적의 설계를 선택할 수 있도록 해 줄 것이다. 이제 이와 같은 새로운 설계도구(design tool)를 제공해 주므로써 초기설계에 각종 생산관련 정보나 지식 및 실적자료가 반영가능토록 발전되었다. 본 논문은 영국의 뉴카슬대학교(Univ. of Newcastle upon Type)에서 위에 언급한 특징들을 반영하여 새로운 선박구조 설계 방법을 개발한 연구결과를 보여주고 있다. 본 선계연구는 5단계로 구분되는데; (1) 컴퓨터 그라픽스를 이용하고 생산정보 데이타베이스와 연결시켜 구조형상(geometry)을 정의하고 구조부재 칫수(scantling) 계산/결정 (2) 블럭 분할(block division) 및 강재 배치(panel arrangement)의 확정을 위해 생산기술 및 건조방식에 대한 정보 제공 (3) 상기 (1) 및 (2)를 활용하여 아래 각 생산 단계에서의 생산작업 분석(work content assessment) a) 생산 준비 단계(Preparation) b) 가공 조립 단계(Fabrication/Assembly) c) 탑재 단계(Erection) (4) 각각의 설계(안)에 대하여 재료비(material cost), 인건비(labour cost) 및 오버헤드 비용(overhead cost)을 산출키 위한 조선소의 생산시설 및 각종 품셈 정보 (5) 총 건조 비용(total production cost)을 산출하여 각각의 설계안을 비교 검토. 본 설계 방식을 산적화물선(Bulk Carrier) 설계에 적용하여 구조배치(structural geometry), 표준화의 정도(levels of standardisation), 구조생산공법(structural topology) 등의 변화에 따른 설계 결과의 민감도를 분석(sensitivity studies)하였다. 전산장비는 설계자의 대화형 접근을 용이하도록 하기 위해 VAX의 화상 처리장치를 이용하여 각 설계안에 대한 구조형상과 작업분석, 건조비 현황 등을 제시할 수 있도록 하였다. 결론적으로 본 연구는 설계초기 단계에서 상세한 건조비 모델(detailed production cost model)을 대화형 화상 처리방법에 접합시켜 이를 이용하여 여러가지 설계안의 도출과 비교검토를 신속히 처리할 수 있도록 함은 물론, 각종 생산 실적정보를 초기설계에 반영하는 최초의 시도라고 믿으며, 생산지향적(Design for Production) 최적설계분야의 발전에 많은 도움이 되기를 기대해 마지 않는다. 참고로 본 시스템의 설계 적용결과를 부록에 요약 소개하며, 상세한 내용은 참고문헌 [4] 또는 [7]을 참조 요망한다.

  • PDF

Change in the Quality Characteristics of Salad Dressing Prepared with Mulberry, Schisandra chinensis and Yam Juice during Storage (저장 기간 중 생마즙, 오미자 및 오디 첨가 샐러드드레싱의 품질 특성 및 항산화능의 변화)

  • Kim, Cho Rong;Yim, Su Bin;Kim, Hyung Don;Oh, Hye Lim;Jeon, Hye Lyun;Kim, Na Yeon;Hong, Yoon Pyo;Lee, Ji Hyun;Kim, Mee Ree
    • Food Science and Preservation
    • /
    • v.19 no.6
    • /
    • pp.825-832
    • /
    • 2012
  • In this study, the quality characteristics and antioxidant activity of mulberry salad dressing prepared with yam juice during storage at $5^{\circ}C$ for four weeks were evaluated. The salad dressing was prepared with a salad base, mulberry, omija, and yam (4:4:6:1 or 4:4:6:3). Fresh yam juice was added to the salad dressing at 0, 7, and 18% levels. After four weeks storage, the pH increased whereas the acidity decreased. As the yam concentration increased, the pH increased to 3.84 and the acidity decreased to 0.14%. The Hunter color L (lightness), b (yellowness), and a (redness) values decreased over the storage period. After four weeks storage, the viscosity increased from 83.2 to 158.5 cp according to the amount of yam juice that was added. The antioxidant activity, such as the DPPH radical scavenging activity, and the total polyphenol content of the salad dressing improved as the yam concentration increased. Moreover, according to the storage time, the peroxide value did not increase. These results show that the mulberry salad dressing to which omija and fresh yam juice were added maintained its freshness with high antioxidative activity during storage.

Effect of amendments and their causes of rice yield increase in ill drained paddy soil (습답(濕沓)에 대(對)한 개량제(改良劑)의 효과(效果)와 유효개량제(有效改良劑)의 수도증수원인(水稻增收原因)에 관(關)한 연구(硏究))

  • Park, Chon Suh;Song, Jae Ha;Kim, Yung Sup;Lee, Chung Young;Choh, Young Sun
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.4 no.1
    • /
    • pp.13-19
    • /
    • 1971
  • In order to establish the method of improving ill drained paddy soil where the accumulation of absorption inhibitor is worried in the earlier stages of rice growth, proper soil is selected and an field experiment is designed having treatments such as lime materials, none sulfate fertilizers, boron and straw etc. The data of yield and plant analysis in different stages of rice growth is eveluated and discussed to obtain following summaries. (1) Significant yield increase was made by the treatment of lime materials such as slacked lime or wollastonite powder, materials inhibiting the activity of microorganisms such as boron and of none sulfate fertilizers lacking inhibitor producing sources. (2) The crop scientifice causes of decreasing yield are the decreasing the number of panicles per hill, grains per panicle and the weight of grains. (3) The plant nutritional causes of decreasing yield are the lowering of nitrogen content throughout the life, phosphate content since young premodia formation stage of plant and the decreased content of magnesium, calcium and silicate in straw at harvesting stage. (4) The causes of lowering the content of various elements in rice plant grown in ill drained paddy soil are suggested as root damage by producing and accumulating absorption inhibitors such as organic acids and hydrogen sulfide etc, from the following observed facts; (a) In young premodia formation stage, attaining to the maximum production and accumulation of absorption inhibitor, the phosphate accumulation in plant was smaller in the phosphate plots than without phosphate plots and much higher in the neutralized plots by adding lime materials. (b) In the plots of straw addition, the potassium content in plant at the young premodia formation stage is very low probabley due to root damage by absorption inhibitor produced from the process of straw decomposition but higher at the stage of harvesting probably due to the immetabolic negative absorption of damaged roots. (c) The effect of boron, known as the inhibitor of microorganism activity to decompose organic matter, is apparent. (d) The effect of nonsulfate fertilizer treatment, having no source of producing inhibitor such as hydrogen sulfide, was significant. (e) All the yield components, decided around the young premodia formation stage attaining to the maximum inhibitor concentration in soil and minimum root activity, are significantly decreased.

  • PDF

Long-term Monitoring Study of Soil Chemical Contents and Quality in Paddy Fields (논토양의 화학성과 질의 장기 변동)

  • Kim, M.S.;Kim, W.I.;Lee, J.S.;Lee, G.J.;Jo, G.L.;Ahn, M.S.;Choi, S.C.;Kim, H.J.;Kim, Y.S.;Choi, M.T.;Moon, Y.H.;Ahn, B.K.;Kim, H.W.;Seo, Y.J.;Lee, Y.H.;Hwang, J.J.;Kim, Y.H.;Ha, S.K.
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.43 no.6
    • /
    • pp.930-936
    • /
    • 2010
  • There is very important to investigate long-term trend of soil chemical properties and quality index for sustainable agriculture and production of agricultural safety products. Monitoring on soil chemical properties in paddy soils was conducted as one cycle with 4 years from 1999 to 2007. Paddy soil samples were taken from 4,007, 1,970, 2,070 sites in 1999, 2003 and 2007, respectively. With these data, soil quality index (SQI) was evaluated by method that Yoon et al suggested in 2004. Chemical properties of paddy soils were 5.8 for pH, 24 g $kg^{-1}$ for organic matter, 132 mg $kg^{-1}$ for available phosphate, 0.29 cmol_c\; kg-1 for exchangeable potassium, 4.7 $cmol_c\;kg^{-1}$ for exchangeable calcium, 1.3 $cmol_c\;kg^{-1}$ for exchangeable magnesium and 126 mg $kg^{-1}$ for available silicate in 2007. Long-term change was shown that pH has increased gradually whereas exchangeable potassium has decreased. However, reasonably large changes were found. Exchangeable calcium and available silicate level in 1999 was 4.0 $cmol_c\;kg^{-1}$, 86 mg $kg^{-1}$, but had risen to 4.7 $cmol_c\;kg^{-1}$, 126 mg $kg^{-1}$ in 2007, respectively. The change of paddy soils quality index was increased gradually and increasement of silicate quality index was higher than other quality indicators.

Risk Assessment of As, Cd, Cu and Pb in Different Rice Varieties Grown on the Contaminated Paddy Soil (중금속 오염 논토양에서 재배된 벼 품종간 위해성평가 비교)

  • Kim, Won-Il;Kim, Jin-Kyoung;Yoo, Ji-Hyock;Paik, Min-Kyoung;Park, Sang-Won;Kwon, Oh-Kyung;Hong, Moo-Ki;Yang, Jay-E;Kim, Jeong-Gyu
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.42 no.1
    • /
    • pp.53-57
    • /
    • 2009
  • Heavy metal pollution may be one of the most serious challenges confront crop production and human health. Therefore, the selection of heavy metal tolerance cultivars which adapted to the contaminated fields will introduced a suitable solution for management this critical environmental risk. The objectives of this research is to assess human health risk using geochemical analyses and exposure assessment of heavy metals in rice cultivars. Risk for inhabitants in the closed mine area was comparatively assessed for As, Cd, Cu and Pb in 10 rice varieties as a major exposure pathway. The average daily dose (ADD) of each heavy metal was estimated by analyzing the exposure pathways to rice and soil. For the non-carcinogenic risk characterization, Hazard Quotient (HQ) and Hazard Index (HI) were calculated using toxicity indices provided by US-EPA IRIS. The different rice varieties revealed a wide range of HI values from 23.6 to 34.3, indicating that all rice varieties have a high potential toxic risk. The DA rice variety showed the lowest HI value while the TB rice variety the highest. The probabilities of cancer risk for As via rice consumption were varied with rice varieties ranging from 2.0E-03 to 3.5E-03 which exceeded the regulatory acceptable risk of 1 in 10,000 set by US-EPA. The DA rice variety also showed the lowest value while the TB rice variety gave the highest value. Our results indicate that risk assessment can be contribute to screen the pollution safe rice cultivars in paddy fields affected by the mining activity.

Evaluation of Heavy Metal Absorption Capacity of Native Plant Species in an Abandoned Coal Mine in South Korea (폐석탄광산지역에 적용가능한 자생식물종의 중금속 흡수능력 평가)

  • Yang, Keum Chul
    • Ecology and Resilient Infrastructure
    • /
    • v.8 no.4
    • /
    • pp.290-298
    • /
    • 2021
  • This study was conducted to evaluate the possibility of applying phytoremediation technology by investigating soil and native plants in waste coal landfills exposed to heavy metal contamination for a long period of time. The ability of native plants to accumulate heavy metals using greenhouse cultivation experiments was alse evaluated. Plants were investigated at an abandoned coal mine in Hwajeolyeong, Jeongseon, Gangwon-do. Two species of native plants (Carex breviculmis. R. B. and Salix koriyanagi Kimura ex Goerz.) located in the study area and three Korean native plants (Artemisia japonica Thunb. Hemerocallis hakuunensis Nakai., and Saussurea pulchella (Fisch.) Fisch.) were cultivated in a greenhouse for 12 weeks in artificially contaminated soil. Soils contaminated with arsenic and lead were generated with arsenic concentration gradients of 25, 62.5, 125, and 250 mg kg-1 and lead concentration gradients of 200, 500, 1000, and 2000 mg kg-1, respectively. Results showed that none of the five plants could survive at high arsenic concentration treatment (125 and 250 mg kg-1) and some plants died in 2000 mg kg-1 lead concentration treatment soil. The plant translocation factor (TF) was highest in H. hakuunensis in arsenic treatments, and A. japonica in lead treatments, respectively. The bioaccumulation factor (BF) of plants was more than 1 in all species in arsenic treatment, whereas it was highest in H. hakuunensis. BF for all species was less than 1 in lead treatment. Particularly, in 2000 mg kg-1 concentration lead treatment, A. japonica accumulated more than 1000 mg kg-1 lead and was expected to be a lead hyperaccumulator. In conclusion, A. japonica and H. hakuunensis were excellent in the accumulation of arsenic heavy metals, and S. koriyanagi was excellent in lead accumulation ability. Therefore, the above mentioned three plants are considered to be strong contenders for application of the phytoremediation technology.

Protective Effect of the Ethyl Acetate-fraction of Methanol Extract of Ophiophogon japonicus on Amyloid beta Peptide-induced Cytotoxicity in PC12 Cells (소엽맥문동-에틸아세테이트 분획물의 아밀로이드 베타단백질-유발 세포독성에 대한 억제 효능)

  • Moon, Ja-Young;Kim, Eun-Sook;Choi, Soo-Jin;Kim, Jin-Ik;Choi, Nack-Shik;Lee, Kyoung;Park, Woo-Jin;Choi, Young-Whan
    • Journal of Life Science
    • /
    • v.29 no.2
    • /
    • pp.173-180
    • /
    • 2019
  • Amyloid ${\beta}$-protein ($A{\beta}$) is the principal component of senile plaques characteristic of Alzheimer's disease (AD) and elicits a toxic effect on neurons in vitro and in vivo. Many environmental factors, including antioxidants and proteoglycans, modify $A{\beta}$ toxicity. It is worthwhile to isolate novel natural compounds that could prove therapeutic for patients with AD without causing detrimental side effects. In this study, we investigated the in vitro neuroprotective effects of the ethyl acetate fraction of methanol extract of Ophiophogon japonicas (OJEA fraction). We used an MTT reduction assay to detect protective effects of the OJEA fraction on $A{\beta}_{25-35}$-induced cytotoxicity to PC12 cells. We also used a cell-based ${\beta}$-secretase assay system to investigate the inhibitory effect of the OJEA fraction on ${\beta}$-secretase activity. In addition, we performed an in vitro lipid peroxidation assay to evaluate the protective effect of the OJEA fraction against oxidative stress induced by $A{\beta}_{25-35}$ in PC12 cells. The OJEA fraction had strong protective effects against $A{\beta}_{25-35}$-induced cytotoxicity to PC12 cells and was strongly inhibitory to ${\beta}$-secretase activity, which resulted in the attenuation of $A{\beta}$ generation. In addition, the OJEA fraction significantly decreased malondialdehyde (MDA) content, which is induced by the exposure of PC12 cells to $A{\beta}_{25-35}$. Our results suggested that the OJEA fraction contained active compounds exhibiting a neuroprotective effect on $A{\beta}$ toxicity.

Effects of Seeding Date on Growth, Yield, and Fatty Acid Content of Perilla Inter-cropped with Sesame in Central Korea (중부지역 참깨 간작 들깨 재배시 파종기가 수량 및 품질에 미치는 영향)

  • Kim, Young Sang;Kim, Ki Hyeon;Yun, Cheol Gu;Heo, Yun Seon;Kim, Ik Jei;Kim, Young-Ho;Song, Yong-Sup;Lee, Myoung Hee
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.66 no.2
    • /
    • pp.138-145
    • /
    • 2021
  • Perilla contains more than 60% of fatty acids. Linolenic acid is effective in preventing heart disease, improving learning ability, treating allergies, and preventing cancer. This study was carried out to improve the cultivation method to aid the stable production of perilla by developing a suitable inter-cropping system with sesame in the central region as well as to report a suitable planting time. The test results are summarized as follows. As the planting time of perilla in the inter-cropping system with sesame was delayed, the number of clusters and capsules decreased. The perilla yields in this system showed significant differences compared to that with the previous crops (sesame varieties) and planting period. The yield of perilla was significantly lower in the characteristic-Type B variety than in the characteristic-Type A variety and decreased significantly as the planting time was delayed. With regards to the quality characteristics of perilla, such as crude protein, crude fat, etc., there were no differences between previous perilla crops and those inter-cropped with sesame. The perilla composition did not show any difference during the planting period; however, with delay in the planting time, crude protein content increased but crude fat content decreased. Yield of perilla was 38% higher in a two-row (40 x 40 cm) system, compared to a single-row cultivation (110 x 20 cm) of perilla inter-cropped with sesame. These results suggest that the suitable method for inter-cropping perilla with sesame in the central region is to sow the characteristic-Type A variety in early May, and cultivate the perilla in two lines (40 x 40 cm) in mid-June. This was judged to be the best cultivation method in the central region.

Inhibitory Effects of Prunus mume Solvent Fractions on Human Colon Cancer Cells (매실 분획물에 의한 인체 대장암세포 억제 효과)

  • Kim, Jeong-Ho;Cho, Hyun-Dong;Won, Yeong-Seon;Heo, Ji-An;Kim, Ji-Young;Kim, Hwi-Gon;Han, Sim-Hee;Moon, Kwang-Deog;Seo, Kwon-Il
    • Journal of Life Science
    • /
    • v.29 no.11
    • /
    • pp.1227-1234
    • /
    • 2019
  • Prunus mume, also known as maesil, is a popular fruit consumed in East Asia (Korea, Japan, and China). It contains high amounts of organic acids, minerals, and polyphenols and has been used as a medication for fever, vomiting, and detoxification. In this study, the anti-proliferative and apoptotic effects of solvent fractions from maesil were evaluated using sulforhodamine B (SRB) assays, morphological evaluations, Hoechst 33258 staining, and western blotting. Addition of the maesil methanol fraction (MMF) and the maesil butanol fraction (MBF) significantly and dose-dependently decreased the cell viability of HT-29 human colon cancer cells. Colony-forming assays confirmed that the MMF and MBF treatments decreased colony numbers when compared with untreated control cells. Treatment of HT-29 cells with MMF and MBF caused a distortion of the cell morphology to a shrunken cell mass. Treatment with MMF and MBF also dose-dependently increased nuclear condensation and the formation of apoptotic bodies in HT-29 cells. Treatment with MMF and MBF significantly and dosedependently increased the expression of Bax (a pro-apoptotic protein), caspase-3, and poly ADP-ribose polymerase (PARP) and decreased the expression of Bcl-2 (an anti-apoptotic protein). MMF significantly and dose-dependently inhibited cell proliferation induced by bisphenol A, an environmental hormone. Therefore, MMF may have potential use as a functional food and as a possible therapeutic agent for the prevention of colon cancer.

Microbial Qualities of Parasites and Foodborne Pathogens in Ready to Eat (RTE) Fresh-cut Produces at the On/Offline Markets (즉석섭취 신선편의 절단 과일 및 채소의 원충류 및 병원성 식중독균의 미생물학적 품질 실태 연구)

  • Jeon, Ji Hye;Roh, Jun Hye;Lee, Chae Lim;Kim, Geun Hyang;Lee, Jeong Yeon;Yoon, Ki Sun
    • Journal of Food Hygiene and Safety
    • /
    • v.37 no.2
    • /
    • pp.87-96
    • /
    • 2022
  • Recently, the purchase of fresh-cut produce and meal kits has increased. Ready-to-eat (RTE) fresh-cut products have potentially hazard of cross-contamination of various microorganisms in the processes of peeling, slicing, dicing, and shredding. There are frequent cases of protozoa food poisoning, such as Cyclospora and Cryptosporidium, caused by fresh-cut products. The objective of the study is to investigate the microbiological qualities of various types of RTE fresh-cut products in the domestic on/offline markets. RTE fresh-cut fruits cup (n=100), fresh-cut vegetables (n=50), and vegetables in meal kits (Vietnamese spring rolls and white radish rolls kits, n=50) were seasonally analyzed. The contamination levels of hygienic indicator organisms, yeast and mold (YM), and foodborne pathogens (Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Salmonella spp., and Escherichia coli O157:H7) were monitored. Overall, the lowest microbiological qualities of meal kits vegetables were observed, followed by RTE fresh-cut fruits cup and fresh-cut vegetables. Contamination levels of total aerobic bacteria, coliforms, and YM in meal kits vegetables were 5.91, 3.90, and 4.71 logs CFU/g, respectively. From the qualitative analysis, 6 out of 200 RTE fresh-cut products (3%) returned positive result for S. aureus. From the quantitative analysis, the contamination levels of S. aureus in purple cabbage from a meal-kit and fresh-cut pineapple were below the acceptable limit (100 CFU/g). Staphylococcus enterotoxin seg and sei genes were detected in RTE fresh-cut celery and red cabbage from meal-kits, respectively. S. aureus contamination must be carefully controlled during the manufacturing processes of RTE fresh-cut products. Neither Cyclospora cayetanensis nor Cryptosporidium parvum was detected in the samples of RTE fresh-cut products and vegetables from meal-kits from the Korean retail markets.