• Title/Summary/Keyword: area reduction

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Research on Mechanical Properties and Characteristics of Hybrid Composites for Boat (보트에 적용되는 하이브리드 복합재에 대한 기계적 특성 연구)

  • Cho, Je-Hyoung;Kim, Sung-Hoon;Yoon, Sung-Won;Ha, Jong-Rok;Kim, Myung-Hyun
    • Journal of Welding and Joining
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    • v.34 no.2
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    • pp.22-29
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    • 2016
  • Recently, Application of composite materials are increased in transport area for weight reduction. Also, Related technical developments have been implemented actively at domestic and abroad. In particular, The carbon fiber has high strength and ultra light property higher than stainless steel, aluminum, GFRP as Eco-friendly material. Carbon fiber contribute to improving the environmental effect such as fuel saving, expansion of loadage, reducing the exhaustion of carbon dioxide through the weight reduction of transport area. In addition, The carbon fiber is applied to the ship in the area of race yacht, luxury cruise boat as weight reduction and high added-value materials, but there is limited application for general boat because price of carbon fiber is very expensive. For the weight reduction of general boat hull, being used as structure materials, glass fiber and carbon fiber are applied to hull with form of hybrid composite materials, but application of domestic and research for development are incomlete. In this study, An evaluations of mechanical strength property and fatigue strength are performed on composite materials by hybrid weaving of glass fiber and carbon fiber and composite materials forming method by hybrid forming.

Assessment of the Soybean Yield Reduction due to Infection of Septoria Brown Spot, Septoria glycines Hemmi (대두 갈색무늬병에 의한 수량감소의 평가)

  • Oh Jeung Haing;Kwon Shin Han
    • Korean journal of applied entomology
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    • v.22 no.1 s.54
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    • pp.7-14
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    • 1983
  • Septoria brown spot closed by Septoria glycines is one of the most serious fungal diseases in soybean. Average yield reduction of 3 varieties for two years was $16.1\%$ by the septoria brown spot inoculation and $9.0\%$ by the natural infection as compared to fungicide-sprayed plots. Number of pods per plant and seed weight were significantly reduced while plant height, number of branches and number of nodes per plant were not affected. Yield reduction was positively correlated to the septoria brown spot severity in all varieties examined. Correlation coefficient $(r=0.38^*)$ between yield reduction and area under the disease progress curve was higher than that (r=0.156) between yield reduction and Van der Plank's apparent infection rate. Potential effect of the septoria brown spot on the soybean yield reduction estimated with the area under the disease progress curve was expressed by the equation of Y=4.38+0.05X $(r=0.0696^*,\;df=25)$.

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Environment-friendly and Low-Carbon Agriculture for Demand-Supply Control and Food Security of Korean Rice (쌀 수급안정과 식량안보를 위한 친환경·저탄소 농업 전환방안)

  • Yang, Seung-Koo;Park, Pyung-Sik;Son, Jang-Hwan;An, Kyu-Nam
    • Korean Journal of Organic Agriculture
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    • v.26 no.1
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    • pp.99-128
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    • 2018
  • The cultivation area of rice as staple grains is decreasing in the domestic situation in Korea. Import volume of a duty in foreign rice is 409,000 tons for a year regardless increasing of production per unit area and decreasing of rice consumption. The total stock of rice is increasing cumulatively despite the effort for production mediation of rice. Therefore, maintenance of cultivation area and reduction of production are necessary for national foodstuffs security problems. Development of environment-friendly and low-carbon technology as alternative of global warming and aging of farm labor power is very important responsibility for descendants with creation of sustainable agriculture environment. As alternative for demand and supply stabilization of rice from all angles, first stage: extension of environment-friendly cultivation area as 17% Jeollanam-do level with maintenance of cultivation area under the present circumstances, second stage: extension of environment-friendly cultivation area as 25%, third stage: extension of environment-friendly cultivation area as 35%. From above mentioned scenario, reduction of rice production (60,000 tons), increases of production cost (59,200,000,000 Won), and reduction of income (201,500,000,000 Won) are estimated in first stage. Reduction of rice production (90,000 tons), increases of production cost (122,100,000,000 Won), and reduction of income (313,700,000,000 Won) are estimated in second stage. Reduction of rice production (380,000 tons), increases of production cost (222,000,000,000 Won), and reduction of income (464,500,000,000 Won) are estimated in third stage. From analysis results for partial tillage in transplanting cultivation complex (10ha), rice production is decreased 1.3~1.5 ton by complex. Production cost of rice is decreased and increases of income cultivation type. Gradual extension of environment-friendly agriculture and low-carbon partial tillage could be expected for environment maintenance of the territorial integrity, confidence of consumer, and high-efficiency of low-cost.

Adaptive Noise Reduction Algorithm for an Image Based on a Bayesian Method

  • Kim, Yeong-Hwa;Nam, Ji-Ho
    • Communications for Statistical Applications and Methods
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    • v.19 no.4
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    • pp.619-628
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    • 2012
  • Noise reduction is an important issue in the field of image processing because image noise lowers the quality of the original pure image. The basic difficulty is that the noise and the signal are not easily distinguished. Simple smoothing is the most basic and important procedure to effectively remove the noise; however, the weakness is that the feature area is simultaneously blurred. In this research, we use ways to measure the degree of noise with respect to the degree of image features and propose a Bayesian noise reduction method based on MAP (maximum a posteriori). Simulation results show that the proposed adaptive noise reduction algorithm using Bayesian MAP provides good performance regardless of the level of noise variance.

Analysis of the Reduction of Light-weight Imapct Noise for Load Condition of Floating Floor (뜬바닥층의 하중조건에 따른 경량충격음 저감량 분석)

  • Kim, Myung-Jun;Lee, Sung-Ho;Yang, Jae-Hoon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.11a
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    • pp.356-360
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    • 2006
  • Recently, for the purpose of improving the isolation performance of impact noise, many resilient materials have been installed in a residential building. As one of the reduction method for improving the performance of light-weight impact noise, this study is focused on the load condition of floating layer over resilient material. We studied the correlation between the mass or load of the floating layer and the reduction of light-weight impact noise by experiments in reverberation chamber for testing the impact noise. The results show that the reduction of impact noise is improved by increasing the mass per unit area of floating layer until about $140kg/m^2$. But the reduction is not obvious by adding extra mass on the floating layer.

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Nipple Reduction with a Pentahedral Excision Technique (오면체 모양 절제법을 이용한 유두축소)

  • Hong, Yoon Gi;Sim, Hyung Bo
    • Archives of Plastic Surgery
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    • v.36 no.3
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    • pp.327-332
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    • 2009
  • Purpose: Several methods of the nipple reduction have been reported. However, the methods described previously are difficult or have some demerits. This study proposes a simple technique for reduction of the nipple height as well as diameter. Methods: The purposed nipple height is marked. A pentahedral design of excision was marked around the nipple. Local anesthetic solution was infiltrated and a 4 - 0 Nylon traction suture was applied at the nipple apex. Excision of the nipple inside both two triangles and a rectangle was made. Remaining two flaps were approximated using 5 - 0 Nylon simple interrupted sutures. However, a part of wound closure was not done in the central area of the nipple. Results: 83 patients(166 nipples) underwent this procedure from December 1999 to December 2008. Follow up ranged from 6 months to 2 years with a mean of 10 months. 78 patients were female and 5 patients were male. No major complication occurred and remaining scars were very inconspicuous. Conclusion: This simple technique has the advantage of nipple reduction in both height and diameter, and provides good aesthetic outcomes.

Changes in Benthic Macrofauna of the Saemangeum Tidal Flat as Result of a Drastic Tidal Reduction (급격한 조석 감소에 의한 새만금 갯벌 대형저서동물 변화)

  • Koo, Bon-Joo;Shin, Sang-Ho;Lee, Seok
    • Ocean and Polar Research
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    • v.30 no.4
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    • pp.485-495
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    • 2008
  • Tidal ranges of inner Saemangeum were largely reduced after the final dyke enclosure, resulting in the former tidal flats becoming either permanently exposed, still influenced by changing tide, or permanently submerged. The effect of reduced tidal range on survival and population stability of tidal flat macrofauna were investigated at three shifted habitats after the dyke completion. At the exposed area, several species survived for 80 days after the dyke enclosure. However, within 120 days, all macrofauna died off due to the elevated temperature during summer. At the intertidal area, some species were maintained until 170 days after the dyke enclosure with a large decrease of the faunal abundance. Species of the submerged area were seen to be more tolerant of the changed environments. The opportunistic species, such as Sinocorophium sinensis, Theora fragilis and Pseudopolydora Kempi, were massively introduced into the submerged area after the dyke enclosure, in which the benthic ecosystem was severely disturbed.

Numerical Analysis on Flow Uniformity According to Area Ratio and Diffuser Angle in an SCR Reactor of a 500 PS-Class Ship (500 PS급 선박 SCR 반응기에서 디퓨저 각도와 면적비에 따른 유동균일도 수치해석)

  • Seong, Hongseok;Park, Inseong;Jang, Hyun;Park, Changdae;Kim, Hyunkyu;Jung, Kyoungyul;Suh, Jeongse
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.24 no.4
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    • pp.394-399
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    • 2015
  • Because flow uniformity affects the life cycle and performance of the catalyst, it is an important design factor for selective catalytic reduction (SCR) systems. We examined how the diffuser angle and the area ratio of the inlet of the SCR reactor to the front of the catalyst affect flow uniformity. For the numerical analysis, we used STAR-CCM+, a common CFD software program. Analysis results showed that the larger the area ratio was, the less the flow uniformity was, and that the longer the diffuser length was, the greater the flow uniformity was. When the area ratio was greater than 1:5, the flow uniformity appeared very similar at the front of the catalyst. As a result, the spread time of the exhaust gas increased and the flow velocity decreased.

Effects of porous pavement on runoff reduction in Boguang subcatchment (투수성 포장도로 도입을 통한 보광배수유역 유출량 저감효과 검토)

  • Jung, Jiyun;Lee, Gunyoung;Ryu, Jaena;Ohe, Jeill
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.2
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    • pp.251-259
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    • 2013
  • Among various Green Infrastructure measures for urban stormwater management, effects of porous pavement were quantitatively examined in terms of hydrological cycle. Different scenarios for porous pavement were introduced on a SWMM model and the effects were compared and analysed using discharge hydrographs. Two types of pavements having different runoff coefficients (0.05 & 0.5) were introduced to cover different ratio of entire road areas (100 %, 77.5 % and 40.4 %) and these made up in total 6 different scenarios. Total runoff volume was reduced and peak flow was significantly decreased by applying the porous pavement. The highest reduction for total runoff was shown from S-6(covering area: 100 %, runoff coefficient: 0.05) as 19 % followed by S-5(covering area: 77.5 %, runoff coefficient: 0.05, 16 %), while that of S-2(covering area: 40.4 %, runoff coefficient: 0.05) and S-1(covering area: 40.4 %, runoff coefficient: 0.5) were the lowest with 8 % and 5 %. This proved that the application of porous pavement would improve urban hydrological cycle.

The Effects of Circuit Training on Abdominal Fat in Obesity Coed (운동에 따른 비만 여대생의 복부지방에 미치는 영향)

  • Song, Myung-Soo;No, Hyun-Jeung;Kim, Sang-Soo
    • PNF and Movement
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    • v.8 no.1
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    • pp.21-29
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    • 2010
  • Purpose : The purpose of this research is to examine the effects of circuit weight training and aerobic exercise on the bodily formation and abdominal fat area of obese female college students. Methods : The female college students whose BMI is over $25kg/m^2$ were divided into the circuit weight training group and the aerobic exercise group and circuit weight training and aerobic exercise were conducted on the respective group five times a week. Resultlts : 1. The tendency of statistically significant reduction in weight, body fat percentage, and BMI was shown in both the circuit weight training group and the aerobic exercise group but there were no significant differences between these groups. 2. The tendency of statistically significant reduction in total abdominal fat area, and subcutaneous fat area was shown in both the circuit weight training group and the aerobic exercise group but there were no significant differences between these groups. 3. Visceral fat area was reduced more in the aerobic exercise group than in the circuit weight training group Conclusion : It was confirmed that exercise alone in the state of no dietary treatment being given could cause obese people bodily formation.

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