• 제목/요약/키워드: Spring hardness

검색결과 97건 처리시간 0.026초

밀 품질평가 현황과 검사제도 (Current Wheat Quality Criteria and Inspection Systems of Major Wheat Producing Countries)

  • 이춘기;남중현;강문석;구본철;김재철;박광근;박문웅;김용호
    • 한국작물학회지
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    • 제47권
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    • pp.63-94
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    • 2002
  • On the purpose to suggest an advanced scheme in assessing the domestic wheat quality, this paper reviewed the inspection systems of wheat in major wheat producing countries as well as the quality criteria which are being used in wheat grading and classification. Most wheat producing countries are adopting both classifications of class and grade to provide an objective evaluation and an official certification to their wheat. There are two main purposes in the wheat classification. The first objectives of classification is to match the wheat with market requirements to maximize market opportunities and returns to growers. The second is to ensure that payments to glowers aye made on the basis of the quality and condition of the grain delivered. Wheat classes has been assigned based on the combination of cultivation area, seed-coat color, kernel and varietal characteristics that are distinctive. Most reputable wheat marketers also employ a similar approach, whereby varieties of a particular type are grouped together, designed by seed coat colour, grain hardness, physical dough properties, and sometimes more precise specification such as starch quality, all of which are genetically inherited characteristics. This classification in simplistic terms is the categorization of a wheat variety into a commercial type or style of wheat that is recognizable for its end use capabilities. All varieties registered in a class are required to have a similar end-use performance that the shipment be consistent in processing quality, cargo to cargo and year to year, Grain inspectors have historically determined wheat classes according to visual kernel characteristics associated with traditional wheat varieties. As well, any new wheat variety must not conflict with the visual distinguishability rule that is used to separate wheats of different classes. Some varieties may possess characteristics of two or more classes. Therefore, knowledge of distinct varietal characteristics is necessary in making class determinations. The grading system sets maximum tolerance levels for a range of characteristics that ensure functionality and freedom from deleterious factors. Tests for the grading of wheat include such factors as plumpness, soundness, cleanliness, purity of type and general condition. Plumpness is measured by test weight. Soundness is indicated by the absence or presence of musty, sour or commercially objectionable foreign odors and by the percentage of damaged kernels that ave present in the wheat. Cleanliness is measured by determining the presence of foreign material after dockage has been removed. Purity of class is measured by classification of wheats in the test sample and by limitation for admixtures of different classes of wheat. Moisture does not influence the numerical grade. However, it is determined on all shipments and reported on the official certificate. U.S. wheat is divided into eight classes based on color, kernel Hardness and varietal characteristics. The classes are Durum, Hard Red Spring, Hard Red Winter, Soft Red Winter, Hard White, soft White, Unclassed and Mixed. Among them, Hard Red Spring wheat, Durum wheat, and Soft White wheat are further divided into three subclasses, respectively. Each class or subclass is divided into five U.S. numerical grades and U.S. Sample grade. Special grades are provided to emphasize special qualities or conditions affecting the value of wheat and are added to and made a part of the grade designation. Canadian wheat is also divided into fourteen classes based on cultivation area, color, kernel hardness and varietal characteristics. The classes have 2-5 numerical grades, a feed grade and sample grades depending on class and grading tolerance. The Canadian grading system is based mainly on visual evaluation, and it works based on the kernel visual distinguishability concept. The Australian wheat is classified based on geographical and quality differentiation. The wheat grown in Australia is predominantly white grained. There are commonly up to 20 different segregations of wheat in a given season. Each variety grown is assigned a category and a growing areas. The state governments in Australia, in cooperation with the Australian Wheat Board(AWB), issue receival standards and dockage schedules annually that list grade specifications and tolerances for Australian wheat. AWB is managing "Golden Rewards" which is designed to provide pricing accuracy and market signals for Australia's grain growers. Continuous payment scales for protein content from 6 to 16% and screenings levels from 0 to 10% based on varietal classification are presented by the Golden Rewards, and the active payment scales and prices can change with market movements.movements.

유기질계 토양개량재를 이용한 절토비탈면 녹화공법 적용시험 연구 (A Study on Application Test of Cut-slope Revegetation Measures with Organic Soil Amendment Materials)

  • 전기성;우경진
    • 한국환경복원기술학회지
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    • 제8권3호
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    • pp.13-20
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    • 2005
  • This study was conducted to suggest the ecological restoration methods of the decomposed granite cut-slope by organic soil amendment materials. Field test carried out for the cut-slope with organic soil amendment materials method and other three revegetation methods in Cheongwon. Test revegetation plants were Festuca arundinacea, Lolium perenne, Dactylis glomerata, Lespedeza cyrtobotrya, and Arundinella hirta. The result of this study can be summarized as follows; 1. The soil hardness, the soil acidity, and the soil humidity of organic soil amendment materials method were at a suitable value for plants growth. And it was better as compared with other three revegetation methods of cutting-rock slopes. 2. The result of toxic substance investigation, all items were at a suitable for standard law. 3. During one year after seeding, most plants germinated and especially Festuca arundinacea and Dactylis glomerata grows well. Seedling numbers were 336.7 per $m^2$(after 6 months), 183.3 per $m^2$(after 10 months), and 353.3 per $m^2$(after 6 months). Ten months later after seeding, plants showed 80% ground coverage. Visual rate, plant height, and growth rate were excellence, Also, high plant growth in spring better than autumn.

SUP7-50CrV4강의 피로강도에 미치는 압축잔류응력의 영향 (The effect of compress residual stresses for fatigue strength of SUP7-50CrV4 Steel)

  • 박경동;정찬기
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2001년도 추계학술대회 논문집
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    • pp.247-252
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    • 2001
  • Recently the steel parts used at automobiles are required to be used under high stress more than ever before in need of the weight down. To achieve this requirement of a high strength steel, it must be necessary to decrease inclusion content and surface defect as like decarburization, surface roughness etc.. In this study, the surface conditions are measured to know the influence on fatigue properties by two cases of shot peening of two-stage shot peening and single-stage shot peening. And for this study, two kinds of spring steel (SUP7, 50CrV4) are used. This study shows the outstanding improvement of fatigue properties at the case of two-stage shot peening in the rotary bending fatigue test and this is assumed to be from on low stress condition, the 1st stage shot peening is not affected by nonmetallic inclusion under metal. it is possible that the 2nd stage shot peening increases the fatigue life and the high stress but that is affected by nonmetallic inclusion under metal. so far beeasily 50CrV4 have made high stress. But, results also show fatigue failures originated at inclusion near surface, and this inclusion type is turned out to be a alumina of high hardness.

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DIN50CrV4-SAE9254강의 피로강도에 미치는 압축잔류응력의 영향 (The Effect of Compressive Residual Stresses on Fatigue Strength in DIN50CrV4-SAE9254 Steel)

  • 박경동;정찬기
    • 한국해양공학회지
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    • 제15권3호
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    • pp.93-99
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    • 2001
  • Recently the steel parts used at automobils are required to be used under high stress more than ever before in need of the weight down. To achieve this requirement of a high strength steel, it must be necessary to decrease inclusion content and surface defect as like decarburization, surface roughness etc.. In this study, the surface conditions are measured to know the influence on fatigue properties by two cases of shot peening of two-stage shot peening and single-stage shot peening. And for this study, two kinds of spring steel (SAE 9254, DIN50CrV4) are used. This study shows the outstanding improvement of fatigue properties at the case of two-stage shot peening in the rotary bending fatigue test and this is assumed to be from (1) on low stress condition, th 1st stage shot peening is not affected by nonmetallic inclusion under metal.(2) it is possible that the 2nd stage shot peening increases the fatigue life and the high stress but that is affected by nonmetallic inclusion under metal. (3) so far beeasily DIN50CrV4 have made high stress. But, results also show fatigue failures originated at inclusion near surface, and this inclusion type is turned out to be a alumina of high hardness.

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JISG4081SUP7-DIN50CrV4강의 피로강도에 미치는 쇼트피이닝의 영향 (Effect of Shot Peening on Fatigue Strength of JISG4081SUP7-DIN50CrV4 Steel)

  • 박경동;정찬기
    • 한국해양공학회지
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    • 제15권4호
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    • pp.66-72
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    • 2001
  • Recently the steel parts used at automobiles are required to be used under high stress more than ever before in need of the weight down. To achieve this requirement of a high strength steel, it must be necessary to decrease inclusion content and surface defect as like decarburization, surface roughness etc.. In this study, the surface conditions are measured to know the influence on fatigue properties by two cases of shot peening of two-stage shot peening and single-stage shot peening. And for this study, two kinds of spring steel (JISG4081SUP7, DIN 50CrV4) are used. This study shows the outstanding improvement of fatigue properties at the case of two-stage shot peening in the rotary bending fatigue test and this is assumed to be from on low stress condition, the 1st stage shot peening is not affected by nonmetallic inclusion under metal. it is possible that the 2nd stage shot peening increases the fatigue life and the high stress but that is affected by nonmetallic inclusion under metal. so far beeasily DIN50CrV4 have made high stress. But, results also show fatigue failures originated at inclusion near surface, and this inclusion type is turned out to be a alumina of high hardness.

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스프링강의 파괴인성에 미치는 쇼트피닝 효과에 관한 연구 (A Study on Effect of Shot Peening on Fracture Toughness of Spring Steel)

  • 하경준;박경동
    • 동력기계공학회지
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    • 제7권2호
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    • pp.66-72
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    • 2003
  • Recently, the steel parts used at the aerospace and automobile industries are required to be used light weight parts. Therefore, used material, steel have to be a high stress, which is an indispensable condition in this field. At the consideration of parts design, high hardness of the lightweight parts have an benefit of saving fuel and material. A high stress of metal has a point of difference according to the shape of design, external cyclic load and condition of vibration. A crack generates on the surface of metal or under yield stress by defect of inner metal defect or surface defect and slowly, this crack grow stable growth. Finally, rapidity failure phenomena is happen. Fatigue failure_phenomena, which happen in metal, bring on danger in human life and property therefor, anti-fatigue failure technology take an important part of current industries Currently, the shot peening is used for removing the defect from the surface of steel and improving the fatigue strength on surface. Therefore, this paper investigated the effect on frcature toughness using shot peening which is improve the resistance of crack growth and crack expansion rate by fatigue that make a compressive residual stress on surface.

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자동차 에어 브레이크 스프링 고정용 SCM435 볼트의 파손 해석 (Failure Analysis of SCM435 Bolt for Fixing Automotive Air Brake Spring)

  • 윤서현;김민헌;남기우
    • 한국산업융합학회 논문집
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    • 제23권1호
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    • pp.73-81
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    • 2020
  • This study analyzed the causes of failure of SCM435 bolts that fix the springs of automobile air brakes that have been fractured during use. The cause of failure was analyzed using SEM, EDS, metallogical microscope and Vickers hardness tester. In the fracture, the ratchet mark began at the outer boundary of crack origin, and the grains at crack origin were found to have clear intergranular corrosion. One SCM435 bolt was subjected to a stress of 398 MPa, it's a stress of about 80% of the fatigue limit. As a result of such a large applied stress, cracks occurred at the corrosion origin and were fractured. In order to prevent the SCM435 bolt from fracture, it is necessary to use the correct composition, the accuracy of heat treatment, preventing damage by external impact, preventing corrosion of the damage part by moisture, and introduction a compressive residual stress by peening.

뽕나무 오갈병에 강한 常一뽕의 동질4배체 ″4原뽕27號″ 創成 (The Breeding of “Sawonppong 27” that is Autotetraploid of the Sangilppong which has Good Mulberry Dwarf Resistance (Morus spp.))

  • 박광준
    • 한국잠사곤충학회지
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    • 제44권1호
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    • pp.1-3
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    • 2002
  • 뽕나무 오갈병의 발생률이 적은 장려뽕품종 “상일뽕”생장점에 Colchicine 적하처리를 하여 4배성인 4원뽕27호를 육성하였으며 그 주요 특성은 다음과 같다. 1. 염색체수는 2n=56인 4배체 이다. 2. 봄철 발아개엽기는 중생뽕이며 잎모양은 타원형과 3열엽이 혼재하는 폭광형이고 잎두께는 두껍다. 3. 가지길이와 마디사이 길이는 짧고 가지 기부의 불발아가 없으며 내동성은 모품종인 상일뽕보다 강하다.

삼중수소 측정에 의한 약수터 물의 수질특성 연구 (Determination of Springwater Characteristics by Measurement of Tritium in Water)

  • 김종훈;최용욱;정택균
    • 대한화학회지
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    • 제40권6호
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    • pp.436-444
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    • 1996
  • 전주근교 약수터 15개 지점에 대하여 그들의 수질특성을 1993년 7월부터 1994년 5월까지 1년 동안에 걸쳐 물속의 삼중수소를 기준으로 삼중수소와 TDS, 삼중수소와 전도도, 삼중수소와 $Cl^-$, 그리고 삼중수소와 총경도의 관계로부터 평가하였다. 이들 약수터 물은 빗물과 유사한 단물, 유동기간이 짧으며 흙층을 통과한 센물, 유동기간이 길고 암반층을 유동한 약한센물, 유동기간이 길고 암반층을 유동한 단물의 특징적 그룹으로 나눌 수 있으며 대부분 빗물과 유사한 물로 해석되었다. Hashimoto의 Mineral Balance Index에 의하면, J-4용천수만 맛있고 건강한 물로 평가되었다.

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잔트커런츠 발효액과 Sourdough 식빵의 품질 특성 (Quality Characteristics of Sourdough Bread with Fermented Zante currants Juice)

  • 김영모
    • 한국식품영양학회지
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    • 제32권3호
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    • pp.259-266
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    • 2019
  • The objective of this study was to investigate quality characteristics of sourdough bread with fermented Zante currants juice. The sweetness of fermented Zante currants starter increased while its pH value decreased as time passed. The pH values were negatively correlated to the added amount of starter with the lowest pH being recorded at 70% addition. Similarly, bread's moisture was inversely correlated to the added amount of starter with the highest moisture content being recorded at 10% addition. For bread's height, excluding the control, 70% addition turned out to be the highest, and the height decreased as the added amount increased. The oven-spring was similar between the control and 70% addition. For the volume, except the control, 70% addition turned out to be the largest. The larger the specific volume was, the higher the volume of bread got. The brightness, redness, and yellowness were decreased as the added amount was increased. For the texture, the control had the highest elasticity and cohesiveness, and they increased as the added amount of starter increased. The hardness had a negative correlation with the added amount, and 70% addition yielded the same result as the control. The adhesiveness appeared only in 10% addition.