• Title/Summary/Keyword: Unit loads

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Estimation of Pollutants Loads using Unit Load Method in Hong-Bo Watershed (원단위법을 이용한 홍보유역의 오염부하량 산정)

  • Kim, Sun-Joo;Lee, Suk-Ho;Heo, Bae-Young
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2001.10a
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    • pp.492-496
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    • 2001
  • The purpose of this study is to estimation of pollutants loads using unit load method in Hong-bo watershed. In general, because river water quality management have been conducted with point source pollutant in our country, pollutants caused by precipitation have not been managed well so far. Especially the pollutants tends to concentrate in the reservoir of reclaimed land. Therefore, the reservoir of reclaimed land is need to continuous monitoring and update of an accurate data. also, It is need to improvement of environmental pollution. There are divide into nine sub-catchments and made an estimate of pollutants loads using unit load method in Hong-bo basin. The sample of data was during the 10 years.

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Effect of connector configuration on the fracture load in conventional and translucent zirconia three-unit fixed dental prostheses

  • Chonticha Subsomboon;Somchai Urapepon
    • The Journal of Advanced Prosthodontics
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    • v.15 no.4
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    • pp.171-178
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    • 2023
  • PURPOSE. The purpose of this study was to determine the effect of the connector configuration on the fracture load in conventional and translucent zirconia of three-unit fixed dental prostheses (FDPs). MATERIALS AND METHODS. Six different three-unit FDPs were prepared (n = 6) from three types of zirconia (3Y-TZP (Katana ML®), 4Y-TZP (Katana STML®), and 5Y-TZP (Katana UTML®)) in combination with two connector configurations (4 × 2.25, 3 × 3 mm). The CoCr master models were scanned, and the FDPs were designed and fabricated using CAD-CAM. The FDPs were cemented on the metal model and then loaded with a UTM at a crosshead speed of 1 mm/min until failure. Two-way ANOVA and Tukey's test were used for statistical analysis (α = .05). RESULTS. Fracture loads of 3Y-TZP (2740.6 ± 469.2 and 2718.7 ± 339.0 N for size 4 × 2.25 mm and 3 × 3 mm, respectively) were significantly higher than those of 4Y-TZP (1868.3 ± 281.6 and 1663.6 ± 372.7 N, respectively) and 5Y-TZP (1588.0 ± 255.0 and 1559.1 ± 110.0 N, respectively) (P < .05). No significant difference was found between fracture loads of 4Y-TZP and 5Y-TZP (P > .05). The connector configuration within 9 mm2 was found to have no effect on the fracture loads on all three types of zirconia (P > .05). CONCLUSION. Fracture loads of three-unit FDPs were affected by the type of zirconia. The fracture loads of conventional zirconia were higher than those of translucent zirconia. However, it was not affected by the connector configuration when the connector had a cross-sectional area of 9 mm2.

Evaluation Method of Structural Safety using Gated Recurrent Unit (Gated Recurrent Unit 기법을 활용한 구조 안전성 평가 방법)

  • Jung-Ho Kang
    • Journal of the Korean Society of Industry Convergence
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    • v.27 no.1
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    • pp.183-193
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    • 2024
  • Recurrent Neural Network technology that learns past patterns and predicts future patterns using technology for recognizing and classifying objects is being applied to various industries, economies, and languages. And research for practical use is making a lot of progress. However, research on the application of Recurrent Neural Networks for evaluating and predicting the safety of mechanical structures is insufficient. Accurate detection of external load applied to the outside is required to evaluate the safety of mechanical structures. Learning of Recurrent Neural Networks for this requires a large amount of load data. This study applied the Gated Recurrent Unit technique to examine the possibility of load learning and investigated the possibility of applying a stacked Auto Encoder as a way to secure load data. In addition, the usefulness of learning mechanical loads was analyzed with the Gated Recurrent Unit technique, and the basic setting of related functions and parameters was proposed to secure accuracy in the recognition and prediction of loads.

Estimation of Production Unit Loads of Livestock Manure Based on TOC (TOC 기반 가축분뇨 발생 원단위 산정)

  • Lee, Yunhee;Kim, Yongseok;Park, Jihyung;Oa, Seong-Wook
    • Journal of Wetlands Research
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    • v.16 no.3
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    • pp.403-409
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    • 2014
  • Assessment of pollutant loads for livestock manure based on total organic carbon (TOC) is being required to apply TOC as an indicator in management of total maximum daily loads. In this study, TOC based unit loads of pig manure known as highly contributing to water pollution assessed. The concentration of pig manure, amount of manure production including cleaning water, and unit loads were investigated targeting 52 farms according to 4 major river basins, rearing form, farm scale, and piggery form. The manure production was highly generated in scraper type of piggery, in small scaled farm rearing sow, and in Han River basin and Nakdong River basin. The averaged manure production was 7.4 L/head/d in total river basins. Averaged concentrations were investigated as TOC 16,037 mg/L, BOD 10,559 mg/L, TN 4,145 mg/L, and TP 503 mg/L. Corresponding unit loads were assessed as TOC 117.1 g/head/d, BOD 77.1 g/head/d, TN 34.7 g/head/d, and TP 3.67 g/head/d.

Equivalent Loads for Spot-Weld Distortions (점용접 변형에 대한 등가하중)

  • Chu, Seok-Jae;Lee, Sang-Hyuk
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.1499-1504
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    • 2007
  • Spot-welding is widely used to construct passenger car bodies in automotive industry. Occasionally severe spot-weld distortions in sub-assembly make further spot-weld difficult. In this paper, distortions for various spot-weld conditions are measured using coordinate measuring machine. Then, based on finite element solution for unit translation or unit rotation of nugget edge, equivalent loads for spot-weld distortions are determined. They can be used to predict the spot-weld distortion using finite element method.

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Study on Vibration Fatigue Analysis of Automotive Battery Supporter (자동차 배터리 지지 구조의 진동 피로 해석에 대한 연구)

  • Ah, Sang Ho
    • Journal of Auto-vehicle Safety Association
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    • v.11 no.4
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    • pp.22-27
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    • 2019
  • In this paper, the vibration load and analysis results for automotive battery supporter were performed to provide efficient vibration tolerance performance prediction methods for single-product vibration tolerance testing, and the major influencing factors and considerations for setting up single-unit vibration tolerance tests were reviewed. A common applicable standard load was applied to efficiently predict the performance of single-unit vibrations through the frequency response analysis technique. The results similar to test results can be predicted by checking vulnerable parts of the vehicle components for vibration loads and applying scale factor to standard loads. In addition, it was confirmed that the test conditions with a frequency generating the same durability severity as the endurance test are needed for accurate prediction of the durability of the single-unit vibration tolerance test conditions, and the acceleration and frequency with the conditions that there is no significant nonlinear phenomena in the vibration system are established during the single-unit vibration tolerance test conditions.

STATCOM Control for Balancing the Unbalanced Loads (불평형 부하의 평형화를 위한 STATCOM 제어)

  • Im, Su-Saeng;Lee, Eun-Ung;Kim, Hong-Gwon
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.49 no.8
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    • pp.522-528
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    • 2000
  • In this paper, a static synchronous compensator(STATCOM), which in general compensates reactive power, is proposed in order to balance the unbalanced loads. Reference values for the compensation of the unbalanced loads currents are determined by 3-phase circuit analysis result. Also the STATCOM control unit is designed considering the proposed compensation scheme for the unbalanced loads. As a result, the effectiveness of the STATCOM for balancing the load currents is verified by computer simulations.

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Assessing unit load in farmland by application of liquid manure and organic farming (액비 및 유기농법 적용에 따른 농경지에서의 오염부하 원단위 평가)

  • So, Hyunchul;Jang, Taeil;Hong, Seung-Gil
    • Journal of Korean Society of Rural Planning
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    • v.23 no.4
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    • pp.39-48
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    • 2017
  • National Institute of Environmental Research (NIER) has proposed new methodology for estimating unit load in order to overcome the limitations of past unit load based on short-term and local area based data. In the case of agricultural land, however, the results presented by NIER are still limited because of various agricultural activities and farmland characteristics. In this study, liquid manure treated paddy field and organic farming upland were selected for considering agricultural diversity. Four different methods for evaluating unit load were used for comparing previous research results. The results of different methods presented various trends compared with those of existing studies. Paddy field treated liquid manure was 1.3 times higher for T-N load and 3.1 times for T-P load than conventional paddy field. Conventional upland was 4.4 times higher for T-N load and 1.8 times higher for T-P load than organic farming upland. In the case of non-conventional farmland, this study showed different values with the unit loads presented by NIER. This implies that it is necessary to review and apply the unit loads considering various agricultural conditions when establishing environmental policy and rural planning.

Comparison of Unit Load from Paddy Field by Various Estimation Methods (산정방법에 따른 논 원단위 비교)

  • Choi, Dongho;Jung, Jaewoon;Yoon, Kwangsik;Choi, Woojung;Cho, Sohyun;Beom, Jina;Yoo, Seungwha
    • Journal of Environmental Impact Assessment
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    • v.24 no.5
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    • pp.407-419
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    • 2015
  • The unit load of paddy field was estimated by several methods and compared in this study. Four year field study was conducted at the paddy fields located in Yeongsan river and Sumjin river basins. The unit load was estimated by four methods; (1) averaging field monitored load; (2) NIER (National Institute of Environmental Research) method which use EMC(Event Mean Concentration) and runoff ratio of rainfall groups with rainfall weighting factors; (3)method using EMC determined by best fit probability distribution; (4)method using arithmetic mean EMC and runoff ratio. The result of this study showed that the unit loads of water quality constituents by field monitoring was similar to those of NIER method whereas those by probability distribution(log-normal, gamma) method were less than unit loads of NIER method. The unit loads by arithmetic mean EMC and runoff ratio were larger than those by NIER method. The unit load by NIER method showed higher BOD, COD, SS, lesser T-N, and similar T-P values when compared to unit loads determined by MOE in 1995.

Contributions to the Impaired Water Bodies by Hydrologic Conditions for the Management of Total Maximum Daily Loads (수질오염총량관리 목표수질 초과지역에 대한 유황별 초과기여도 분석)

  • Park, Jun Dae;Oh, Seung Young
    • Journal of Korean Society on Water Environment
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    • v.28 no.4
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    • pp.574-581
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    • 2012
  • It is important to analyze the status of water quality with relation to the stream flow to attain water quality goal more effectively in the unit watersheds for the management of Total Maximum Daily Loads (TMDLs). This study developed a flow duration-water quality distribution graph to figure out water quality appearances on the flow variation and analyzed contributions of water quality observations to the impaired water bodies quantitatively by hydrologic conditions. Factors relating to water quality variation can be analyzed more precisely and assessed on the base of quantified contributions. It is considered that this approach could be utilized to establish a more effective plan for the water quality improvement including the prioritization of pollution reduction options.