• Title/Summary/Keyword: Chemical Quality Control

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Polymer Quality Control Using Subspace-based Model Predictive Control with BLUE Filter

  • Song, In-Hyoup;Yoo, Kee-Youn;Rhee, Hyun-Ku
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.357-357
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    • 2000
  • In this study, we consider a multi-input multi-output styrene polymerization reactor system for which the monomer conversion and the weight average molecular weight are controlled by manipulating the jacket inlet temperature and the feed flow rate. The reactor system is identified by using a linear subspace identification method and then the output feedback model predictive controller is constructed on the basis of the identified model. Here we use the Best Linear Unbiased Estimation (BLUE) filter as a stochastic estimator instead of the Kalman filter. The BLUE filter observes the state successfully without any a priori information of initial states. In contrast to the Kalman filter, the BLUE filter eliminates the offset by observing the state of the augmented system regardless of a priori information of the initial state for an integral white noise augmented system. A BLUE filter has a finite impulse response (FIR) structure which utilizes finite measurements and inputs on the most recent time interval [i-N, i] in order to avoid long processing times.

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Quality of Raw Ginseng and Quality Control of Ginseng Products (원료삼품질과 제품의 품질관리)

  • Park, Hoon
    • Journal of Ginseng Research
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    • v.15 no.3
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    • pp.224-230
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    • 1991
  • The seven traditional quality factors including age and root weight ect. were reviewed in relation to the chemical components as a new quality factor and pharmacological data. The other important factor, production place, appeared to be sum of the eight factors. The important of production place indicated that the best quality ginseng is produced in the optimum environment. The description of ginseng for medicinal use in present materia medica missed most traditional quality factors only indicating the change by processing. Such phenomena do not mean the significant of raw$.$ ginseng quality. since appropriate raw ginseng was supplied in traditional way. For the generation with analytical attitude the description of raw ginseng quality to the processed ginseng products is recommendable. For the quality control with biologically active or index compound, the composition of various compounds seems to be the best. The establishment of physical and chemical quality creteria that will match with the traditional mothod it needed and will accomplished by comparative research on raw ginseng from various production sites and growth conditions. The description of production-place, grade and quantity of raw ginseng to the processed products will give better information and higher popularity of products to consumers.

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Effect of Pig Slurry Application on the Mineral Content of Leaf, Fruit Quality and Soil Chemical Properties in Pear Orchard (돈분 액비 시용이 배나무 잎의 무기성분 함량, 과실특성과 토양화학성에 미치는 영향)

  • Park, Jin-Myeon;Lim, Tae-Jun;Lee, Seong-Eun
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.2
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    • pp.209-214
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    • 2012
  • This experiment was carried out to investigate the replaceability of chemical fertilizer by SCB liquid fertilizer (SCB) in pear orchard for 5 years. The effects on the mineral content of leaf, fruit quality, yield and soil chemical properties are as follows: The mineral content of leaf showed no difference between the treatments; two SCB liquid fertilizer treatments based on the N (SCB-N) and K (SCB-K) content, and control (chemical fertilizer application). There were no significant differences in yield, titratable acidity and weight of the fruit although the figure of fruit weight was high in SCB-N treatment. Soluble solids content was higher in the SCB treatments than the control. Soil chemical properties such as the content of soil organic matter, available soil phosphate and exchangeable cation were not different, although soil pH was higher in SCB treatments. In conclusion, it is suggest that the use of chemical fertilizer in pear orchard could be replaced by the application of SCB liquid fertilizer because of the same effect on the growth of pear tree and soil chemical properties.

Growth Performance and Meat Quality of Broiler Chickens Supplemented with Bacillus licheniformis in Drinking Water

  • Liu, Xiaolu;Yan, Hai;Lv, Le;Xu, Qianqian;Yin, Chunhua;Zhang, Keyi;Wang, Pei;Hu, Jiye
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.5
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    • pp.682-689
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    • 2012
  • A feeding trial was conducted to investigate effects of Bacillus licheniformis on growth performance and meat quality of broilers. Nine hundred one-d-old broiler chicks were randomly assigned to 3 experimental groups with three replicate pens of 100 broiler chicks. Three treatments were i) control, ii) basal diets supplemented with 1 ml of B. licheniformis for each in feed water per day iii) basal diets supplemented with 2 ml of B. licheniformis per chick in feed water per day. The supplementation of B. licheniformis significantly increased body weight in grower chickens (p<0.05), and significantly improved the feed conversion in 3 to 6 and 0 to 6 wk feeding period compared with the control group (p<0.05). Additionally, the supplement also resulted in increased protein and free amino acid contents, and decreased fat content in chicken breast fillet (p<0.05). Furthermore, improvement in sensory attributes was observed in broilers fed with the probiotic. In conclusion, B. licheniformis treatments resulted in a significant increase (p<0.05) in broiler productivity based on an index taking into account daily weight gain and feed conversion rate. Meanwhile, the probiotic contributed towards an improvement of the chemical, nutritional and sensorial characteristics of breast fillet. Overall, the study indicates that B. licheniformis can be used as a growth promoter and meat quality enhancer in broiler poultry.

Automatic Determination of Coagulant Dosing Rate Using Fuzzy Neural Network (Fuzzy Neural Network에 응집제 투입률의 자동결정)

  • Chung, Woo-Seop;Oh, Sueg-Young
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.1
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    • pp.101-107
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    • 1997
  • Recently, as the raw water quality becomes to be polluted and the seasonal and local variation of water quality becomes to be severe, an exact control of coagulant dosing have been required in the water treat- ment plant. The amounts of coagulant is related to the raw water quality such as turbidity, alkalinity, water temperature, pH and edectrical conductivity. However the process of chemical reaction has not been clarified so far, so the dosing rate has been decided by jar-test, which is taken one or two hours. For the sake of this coagulant dosing control, fuzzy neural network to fuse fuzzy logic and neural network was proposed, and the scheme was applied to automatic determination of coagulant dosing rate. This controller can automatically identify the if-then rules and tune the membership functions by utilizing expert's cintrol data. It is shown that determination of coagulant dosing rate according to real time sensing of water quality is very effect.

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Fuzzy modeling and control for coagulant dosing process in water purification system (상수처리시스템 응집제 주입공정 퍼지 모델링과 제어)

  • 이수범;남의석;이봉국
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.282-285
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    • 1996
  • In the water purification plant, the raw water is promptly purified by injecting chemicals. The amount of chemicals is directly related to water quality such as turbidity, temperature, pH and alkalinity. At present, however, the process of chemical reaction to the turbidity has not been clarified as yet. Since the process of coagulant dosage has no feedback signal, the amount of chemical can not be calculated from water quality data which were sensed from the plant. Accordingly, it has to be judged and determined by Jar-Test data which were made by skilled operators. In this paper, it is concerned to model and control the coagulant dosing process using jar-test results in order to predict optimum dosage of coagulant, PAC(Polymerized Aluminium Chloride). The considering relations to the reaction of coagulation and flocculation, the five independent variables(turbidity, temperature, pH, Alkalinity of the raw water, PAC feed rate) are selected out and they are put into calculation to develope a neural network model and a fuzzy model for coagulant dosing process in water purification system. These model are utilized to predict optimum coagulant dosage which can minimize the water turbidity in flocculator. The efficacy of the proposed control schemes was examined by the field test.

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Effect of Drying Methods on the Field Drying Rate and Quality of Alfalfa and Spring Oats Hay (건조방법별 알팔파와 봄 연맥의 건초조제 효과)

  • Seo, Sung;Kim, Jong-Geun;Chung, Eui-Soo;Lee, Jong-Kyong;Kim, Won-Ho;Shin, Dong-Eun
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.21 no.2
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    • pp.67-74
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    • 2001
  • A field experiment was carried out to determine the effects of chemical/mechanical treatments at mowing on the field drying rate and hay quality of alfalfa(Medicago sativa L., cv. Vernal) and spring oats(Avena satvia L., cv. Swan). The chemical drying agent of 2% $K_2CO_3$, mechanical mower conditioning, and no treatment(control) were treated for hastening hay-making in the spring of 1997. The forages were harvested at early bloom stage in alfalfa and heading stage in oats. After field dry, square bales were made by hay baler, and the dry matter(DM) loss, visual estimation and nutritive value of hay were evaluated after storing two months. The field drying rates of alfalfa and oats were high at mechanical treatment, but the drying effectiveness of chemical agents alone was very low. With mower conditioning, the duration of field dry was shortened by 1 day compared with control. therefore, mower conditioning enhance the field drying rate of alfalfa and oats. The DM loss of alfalfa and oats hay was reduced by mechanical treatment, but the efficiency by chemical alone was low. The visual score(leafiness, green color, odor and softness) of hay at mechanical treatment was slightly higher than that of chemical and control. The nutritive value(ADF, NDF, in vitro digestibility, and relative feed value) of hay was also high with treatment of mechanical, but those of chemical alone were similar compared with control. The nutritive value of hay after two months in both alfalfa and oats was decreased when compared with at harvest.

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Effect of Crystal Orientation on Material Removal Characteristics in Sapphire Chemical Mechanical Polishing (사파이어 화학기계적 연마에서 결정 방향이 재료제거 특성에 미치는 영향)

  • Lee, Sangjin;Lee, Sangjik;Kim, Hyoungjae;Park, Chuljin;Sohn, Keunyong
    • Tribology and Lubricants
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    • v.33 no.3
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    • pp.106-111
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    • 2017
  • Sapphire is an anisotropic material with excellent physical and chemical properties and is used as a substrate material in various fields such as LED (light emitting diode), power semiconductor, superconductor, sensor, and optical devices. Sapphire is processed into the final substrate through multi-wire saw, double-side lapping, heat treatment, diamond mechanical polishing, and chemical mechanical polishing. Among these, chemical mechanical polishing is the key process that determines the final surface quality of the substrate. Recent studies have reported that the material removal characteristics during chemical mechanical polishing changes according to the crystal orientations, however, detailed analysis of this phenomenon has not reported. In this work, we carried out chemical mechanical polishing of C(0001), R($1{\bar{1}}02$), and A($11{\bar{2}}0$) substrates with different sapphire crystal planes, and analyzed the effect of crystal orientation on the material removal characteristics and their correlations. We measured the material removal rate and frictional force to determine the material removal phenomenon, and performed nano-indentation to evaluate the material characteristics before and after the reaction. Our findings show that the material removal rate and frictional force depend on the crystal orientation, and the chemical reaction between the sapphire substrate and the slurry accelerates the material removal rate during chemical mechanical polishing.

Effect of Cover Crop Species and Liquid Manure Application Rate on Green Manure Production, Leaf Mineral Content, Fruit Quality and Soil Chemical Properties in Pear Orchard

  • Lee, Seong Eun;Park, Jin Myeon;Park, Young Eun;Choi, Dong Geun
    • Korean Journal of Soil Science and Fertilizer
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    • v.47 no.6
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    • pp.558-562
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    • 2014
  • Cover cropping and liquid manure application are considered as effective ways to replace the use of chemical fertilizer in orchard. This study was conducted to investigate the effect of cover crop species and liquid manure application rate on green manure production, leaf mineral content, fruit quality and soil chemical properties in pear orchard. The treatments include rye and hairy vetch as cover crops, two liquid manure application levels based on N and $K_2O$ requirement on each cover crop species, and chemical fertilizer as control. Green manure production was higher in hairy vetch than in rye. K content of pear leaves and soil exchangeable K content increased in N based liquid manure application treatments. The yield was higher in rye + liquid manure and fertilizer treatments, and fruit quality was not different between the treatments. Taking all of these into account, rye + $K_2O$ requirement-based liquid manure application is recommended in pear orchard for not only sufficient nutrient supply but also prevention of any problem related with soil $K_2O$ accumulation in pear orchard in long-term perspective.