• 제목/요약/키워드: Low grade

검색결과 2,655건 처리시간 0.03초

옥천대(沃川帶) 함(含)우라늄지층중(地層中)의 우라늄과 타성분(他成分)과의 상관관계(相關關係) (Geochemical Correlations Between Uranium and Other Components in U-bearing Formations of Ogcheon Belt)

  • 이민성;전효택
    • 자원환경지질
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    • 제13권4호
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    • pp.241-246
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    • 1980
  • Some components in uranium-bearing formations which consist mainly of black shale, slate. and low grade coal-bearing formation of Ogcheon Belt were processed statistically in order to find out the geochemical correlations with uranium. Geochemical enrichment of uranium, vanadium and molybdenum in low grade coal-bearing formations and surrounding rocks is remarkable in the studied area. Geochemical correlation coefficient of uranium and molybdenum in the rocks displays about 0.6, and that of uranium and fixed carbon about 0.4. Uranium and vanadium in uranium-bearing low grade coals denote very high correlation with fixed carbon, which is considered to be responsible for enrichment of metallic elements, especially molybdenum. Close geochemical correlation of uranium-molybdenum couple in the rocks can be applied as a competent exploration guide to low grade uranium deposits of this area.

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저 품위 철광석을 사용한 식생용 투수 콘크리트의 중성화 및 제작에 관한 연구 (A Study on Chemical Neutralization and Production of Planting Porous Concrete Using Low-Grade Iron Ore)

  • 은희창;이민수;배충열
    • 산업기술연구
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    • 제27권A호
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    • pp.31-38
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    • 2007
  • Recently produced concrete has a tendency to overcome environmental defects. Porous and planting Eco-concrete requires the neutralization process and enough void in concrete to contain water, to pass air freely, and provides necessary nutrients to vegetation roots. The biological environment in concrete is not suitable for planting because the concrete possesses strong alkali constituent of pH 11-13. This study evaluated the strength and serviceability of concrete as well as the chemical characteristics of concrete mixed by low-grade iron ore left in the abandoned mine and treated by Ammonium monohydrogen phosphate, $(NH_4)_2HPO_4$. Test variables include two kinds of coarse aggregates such as crushed stones and low-grade iron ore, the duration time and the period for neutralization treatment by Ammonium monohydrogen phosphate, $(NH_4)_2HPO_4$, and the proportion ratio of cement, blast furnace slag and silica fume.

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경부 피부에서 발생한 저등급 근섬유모세포 육종 증례 보고 (A Case Report of Cutaneous Low-grade Myofibroblastic Sarcoma in the Neck)

  • 박한나라;임준현;박효천;여현정
    • 대한두경부종양학회지
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    • 제38권2호
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    • pp.15-18
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    • 2022
  • Myofibroblastic sarcoma can be classified as low-, intermediate-, and high-grade. Low-grade myofibroblastic sarcoma (LGMS) is uncommon and rarely appears on the skin. LGMS is diagnosed based on histopathological and immunohistochemical findings. Additionally, LGMS metastases are rare as well. Herein, the authors describe a case of cutaneous LGMS in the neck. To the best of our knowledge, there are no cases regarding cutaneous LGMS in the neck present in the existing literature. Surgical resection is considered as the most important treatment for LGMS. Therefore, a complete tumor resection was performed in this case. However, another mass in the uterus was identified on abdominal computed tomography performed post-surgery.

POSITION RECOGNITION AND QUALITY EVALUATION OF TOBACCO LEAVES VIA COLOR COMPUTER VISION

  • Lee, C. H.;H. Hwang
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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    • pp.569-577
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    • 2000
  • The position of tobacco leaves is affluence to the quality. To evaluate its quality, sample leaves was collected according to the position of attachment. In Korea, the position was divided into four classes such as high, middle, low and inside positioned leaves. Until now, the grade of standard sample was determined by human expert from korea ginseng and tobacco company. Many research were done by the chemical and spectrum analysis using NIR and computer vision. The grade of tobacco leaves mainly classified into 5 grades according to the attached position and its chemical composition. In high and low positioned leaves shows a low level grade under grade 3. Generally, inside and medium positioned leaf has a high level grade. This is the basic research to develop a real time tobacco leaves grading system combined with portable NIR spectrum analysis system. However, this research just deals with position recognition and grading using the color machine vision. The RGB color information was converted to HSI image format and the sample was all investigated using the bundle of tobacco leaves. Quality grade and position recognition was performed through well known general error back propagation neural network. Finally, the relationship about attached leaf position and its grade was analyzed.

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대뇌 종양에서 자기공명 분광법 적용 결과의 분석 연구 (The Analysis of Brain Tumor's Grades Using Magnetic Resonance Spectroscopy)

  • 윤상준;임종수
    • 대한방사선기술학회지:방사선기술과학
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    • 제31권4호
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    • pp.355-365
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    • 2008
  • 대뇌 종양의 질환에서 Tumor의 정도를 M.R.S(MR Spectroscopy)를 이용하여 질환의 등급별 비교 분석과 특성을 연구하고자 하였다. M.R.S의 STEAM과 PRESS의 Protocol를 이용하여 High grade Tumor와 Low grade Tumor의 성분을 절편화 하고 질환별 Voxel의 Spectrum의 신호를 얻어서 질환의 생화학적 정보를 정량 분석하고, 각각 실험 결과에 대하여 비교 분석하여 질환의 성분 분석과 질환의 유형을 이해하고자 하였다. High grade Tumor에서는 NAA/Cr이 29.4%와 53.9%의 신호 감소를 보였고, Cho/Cr은 570%와 711%의 급격한 신호 증가를 보임을 알 수 있었고, Low grade Tumor에서는 NAA/Cr이 42.6%와 58.1%의 신호 감소를 보였고, Cho/Cr은 188%와 195%의 신호 증가를 보임을 알 수 있었다. 그리하여, 각 신호의 비교분석을 통한 종양의 정도와 특성을 이해할 수 있었고, 여러 인체장기에 폭 넓은 연구와 자료 확립을 하여야 할 것이다.

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Effect of Tart Cherry Juice Consumption on Body Composition and Anthropometric Measures: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

  • Mohammad Reza Amini;Nastaran Payandeh;Fatemeh Sheikhhossein;Hossein Shahinfar;Sanaz Pourreza;Azita Hekmatdoost
    • Clinical Nutrition Research
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    • 제12권1호
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    • pp.65-76
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    • 2023
  • The present systematic review and meta-analysis were accomplished to understand the effects of tart cherry juice consumption on body composition and anthropometric measures. Five databases were searched using relevant keywords from inception to January 2022. All clinical trials investigating the effect of tart cherry juice consumption on body weight (BW), body mass index (BMI), waist circumference (WC), fat mass (FM), fat-free mass (FFM), and percentage body fat (PBF) were included. Out of 441 citations, 6 trials that enrolled 126 subjects were included. Tart cherry juice consumption significantly did not reduce BW (weighted mean difference [WMD], -0.4 kg; 95% confidence interval [CI], -3.25 to 2.46; p = 0.789; GRADE = low), BMI (WMD, -0.07 kg/m2; 95% CI, -0.89 to 0.74; p = 0.857; GRADE = low), FM (WMD, 0.21 kg; 95% CI, -1.83 to 2.25; p = 0.837; GRADE = low), FFM (WMD, -0.12 kg; 95% CI, -2.47 to 2.27; p = 0.919; GRADE = low), WC (WMD, 1.69 cm; 95% CI, -1.88 to 5.27; p = 0.353; GRADE = low), and PBF (WMD, 0.18%; 95% CI, -1.81 to -2.17; p = 0.858; GRADE = low). Overall, these data suggest that tart cherry juice consumption has no significant effect on BW, BMI, FM, FFM, WC, and PBF.

성장에 따른 중학생 척추측만증 이행양상 (Scoliosis Progression according to the Growth of Middle School Students)

  • 김죽향;김은주
    • 지역사회간호학회지
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    • 제14권3호
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    • pp.479-487
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    • 2003
  • Purpose: This study was conducted to investigate the progression of Cobb's angle of middle school students according to the Risser grade changes during a one-year follow up period, and to identify the prevalence rate and related factors regarding scoliosis. Method: A total of 2,124 middle school students were preliminarily screened by the Adam's forward bending test. Among them, 21 adolescents diagnosed with scoliosis (above 5Cobb's angle) by X-Raying were the subjects and followed up for checking Cobb's angle and the Risser grade for one year. Results: The overall prevalence of scoliosis in middle school students was 2.13% and the prevalence in girls was higher than in boys. The Cobb's angle was significantly high in seniors and girls. The cases in low angle and low Risser grade demonstrated significant changes in progressive Cobb's angle compared to the cases in high angle and high Risser grade after one-year. But gender and pattern of curvature were not significantly different from the changes scoliosis angle after one-year. Conclusion: Based on these study results, juniors in low Risser grade were inclined to aggravate scoliosis despite the low degree of curvature at the first measurement.

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일반용 저압전기설비의 안전등급제 도입에 관한 연구 (A Study on Improvement of Safety Management of Low Voltage Electrical Equiment)

  • 한재필;최용성
    • 한국전기전자재료학회논문지
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    • 제36권6호
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    • pp.598-602
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    • 2023
  • With the purpose of instilling an awareness of the safety of users of electrical equipment and inducing voluntary facility improvement through the safety rating system for general low voltage electrical equipment, simulation and field application of the safety rating of general low voltage electrical equipment were conducted. For the introduction and application of the safety rating system for general low-voltage electrical equipment, data related to domestic safety was investigated and analyzed, cases of introduction in other fields were reviewed, and for design, the 4M risk assessment method of the Korea Occupational Safety and Health Agency and the cases of safety index development in Korea were analyzed and standardized. Safety rating system simulations were conducted for general low-voltage electrical equipment, and problem improvement measures were prepared by analyzing the results through on-site verification and simulation applied to the initial design. Design standards for the introduction of the safety rating system for general low-voltage electrical equipment were prepared, and 394 youth training facilities were applied to the field to see if the design standards were practically applicable to the field. With the application of the safety rating system for low-voltage electrical equipment for general use, youth training facilities that had been classified as 'appropriate' were able to induce an upgrade to a higher level through voluntary facility improvement according to the application of grades (A to E). As a result of inducing voluntary repair projects based on the results of the 1st and 2nd inspection of youth training facilities, it was confirmed that 86 facilities received grade A, 225 facilities received grade B, and only 311 facilities received grade A to B out of a total of 394 facilities, and there was no grade E.

비선호 부위 소고기의 저온처리에 의한 품질향상 및 소고기의 숙성효과 (Quality improvement and aging effect of beef by low-temperature treatment of non-preferred parts of beef)

  • 김현경;김순철;김현진;김영미
    • 문화기술의 융합
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    • 제9권5호
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    • pp.753-760
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    • 2023
  • 본 연구에서는 1++등급 소고기에 비해 1등급 저온처리 및 숙성기간에 따른 소고기의 품질향상 및 숙성효과를 시도하였다. 1++등급 소고기의 지방함량과 전단력은 13.03%와 114.26N이었으나, 1등급 소고기는 3.21%와 149.67N이었다. 한편, 1등급 소고기를 -26℃에서 12시간 저온처리하고 0℃에서 14일간 저온 숙성한 결과 전단력은 87.85N으로 크게 감소하였으며 전체적인 기호도, 부드러움, 다즙성, 풍미 및 씹는 질감는 향상되었다. 필수 유리아미노산 함량은 1++ 등급 소고기에서 22.17mg/100g으로 낮았으나 1등급 3개 시료에서 41.31~45.11 mg/100g으로 함량이 높았으며, 저온처리에 따른 함량 변화는 없었다. 소고기의 특정 성분으로 타우린은 30.94~34.41 mg/100g으로 소고기 등급에 따른 함량차이는 적었지만 Anserine과 Creatine은 19.68 mg/100g, 소고기 1++등급은 70.01 mg/100g으로 낮았다. 단일불포화지방산/포화지방산 비율로서의 올레산(c18:1)/스테아르산(c18:0)의 함량비는 1++등급 소고기는 5.29로 낮았으나 1등급 쇠고기는 6.13~6.78로 높았다. 또한 1등급 소고기는 저온처리 조건 및 숙성기간에 따른 이들 지방산의 함량비에 변화가 없었다. 본 연구 결과, -26℃에서 12시간 동안 저온 처리한 후 0℃에서 14일 동안 숙성함으로써 1등급 소고기의 품질을 향상시킬 수 있었다.

저가형 탄소섬유 개발을 위한 자외선 조사 기반 의류용 PAN 섬유의 연속식 안정화 공정 개발 (Developing Continuous Stabilization Process for Textile-Grade PAN Fiber-Based Carbon Fiber Using UV Irradiation)

  • 문준하;성홍규;유지선;조세연;최재원
    • 한국분말재료학회지
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    • 제29권5호
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    • pp.418-423
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    • 2022
  • Carbon fibers (CFs) are considered promising composite materials for various applications. However, the high cost of CFs (as much as $26 per kg) limits their practical use in the automobile and energy industries. In this study, we developed a continuous stabilization process for manufacturing low-cost CFs. We employed a textile-grade polyacrylonitrile (PAN) fiber as a low-cost precursor and UV irradiation technique to shorten the thermal stabilization time. We confirmed that UV irradiation on the textile-grade PAN fibers could lower the initial thermal stabilization temperature and also lead to a higher reaction. These resulted in a shorter overall stabilization time and enhancement of the tensile properties of textile-grade PAN-based CFs. Our study found that only 70 min of stabilization time with UV irradiation was required to prepare textile-grade PAN-based low-cost CFs with a tensile strength of 2.37 ± 0.22 GPa and tensile modulus of 249 ± 5 GPa.