• Title/Summary/Keyword: Combined Deterioration

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Comparision of Combined Stress Tests for Predicting Field Emergence of Lotus corniculatus and Trifolium pratense (Birdsfoot Trefoil과 Red Clover의 포장출현율 예측을 위한 몇가지 Stress 검정법 비교)

  • Kim, Seok-Hyeon;Choe, Zhin-Ryong;Chung, Min-Hong;Han, Kyeong-Ho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.37 no.2
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    • pp.171-177
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    • 1992
  • The purpose of this study was to compare the test methods for predicting field emergence of Lotus corniculatus and Trifolium pratense. Four seed lots of two herbage legumes were controlled deteriorated, accelerated aged before germination test and conductivity of each seed lot was determined. Those germination percent and conductivity of seed lots were compared with actual field emergence rate. Field emergence rate could be estimated by the controlled deterioration test ($R^2$=0.687), by the accelerated aging test ($R^2$=0.260), and by the conductivity test ($R^2$=0.238). A multiple regression equation for predicting field emergence rate(equation omitted) was estimated as (equation omitted)=-198.16 + 2.3493X$_1$-1.5564X$_2$ + 1.9812X$_3$where X$_1$, percent germination of controlled deterioration test ; X$_2$, percent germination of accelerated aging test; and X$_3$, conductivity of solute leakage in the conductivity test. Conclusively, unless multiple tests are not available, the controlled deterioration test was comparatively high efficient for predicting field emergence rate, however, the combined measurements of those three tests can enhance the efficiency.

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The Study for the Air Bubble Deterioration of Combined High Flowing Self-Compacting Concrete (병용계 고유동 자기충전콘크리트의 기포저감을 위한 연구)

  • Choi, Yun-Wang;Kim, Kyung-Hwan;Ruy, Deug-Hyun;Jeong, Jae-Gwon;Kang, Hyun-Jin;Lee, Jae-Nam
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.449-452
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    • 2008
  • This study is to manufacture HSCC (High flowing Self-Compacting Concrete) be able to construction without vibration & hardening, and it is stable according to the change of the surface number of aggregate and to examine the factor of reduction occurred before after hardening through the indoor experiment. It is essential to use of the thickener to increase the viscosity in the combined HSCC. In this result, it make more bubbles than HSCC of pulverulent body. The result of study has shown, through the surface air bubble by not passed air bubbles within concrete after hardening, It has bad effect in not only appearance of structures but strength & duration. It is the experiment for air bubble of concrete according to the types of aggregate (fine aggregate), mixing time of concrete, exfoliation, material of model form and so that reduce the air bubble of combined HSCC. Experiments have shown, the effect of exfoliation was bigger than the effect of form for the performance of surface finishing of combined HSCC after hardening according to the exfoliation or material of model form and the opaque guris has good condition of finishing.

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A Numerical Model for the Freeze-Thaw Damages in Concrete Structures

  • Cho Tae-Jun
    • Journal of the Korea Concrete Institute
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    • v.17 no.5 s.89
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    • pp.857-868
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    • 2005
  • This paper deals with the accumulated damage in concrete structures due to the cyclic freeze-thaw as an environmental load. The cyclic ice body nucleation and growth processes in porous systems are affected by the thermo-physical and mass transport properties, and gradients of temperature and chemical potentials. Furthermore, the diffusivity of deicing chemicals shows significantly higher value under cyclic freeze-thaw conditions. Consequently, the disintegration of concrete structures is aggravated at marine environments, higher altitudes, and northern areas. However, the properties of cyclic freeze-thaw with crack growth and diffusion of chloride ion effects are hard to be identified in tests, and there has been no analytic model for the combined degradations. The main objective is to determine the driving force and evaluate the reduced strength and stiffness by freeze-thaw. For the development of computational model of those coupled deterioration, micro-pore structure characterization, pore pressure based on the thermodynamic equilibrium, time and temperature dependent super-cooling with or without deicing salts, nonlinear-fracture constitutive relation for the evaluation of internal damage, and the effect of entrained air pores (EA) has been modeled numerically. As a result, the amount of ice volume with temperature dependent surface tensions, freezing pressure and resulting deformations, and cycle and temperature dependent pore volume has been calculated and compared with available test results. The developed computational program can be combined with DuCOM, which can calculate the early aged strength, heat of hydration, micro-pore volume, shrinkage, transportation of free water in concrete. Therefore, the developed model can be applied to evaluate those various practical degradation cases as well.

Effecs of Dipping and Preheating Treatments on Quality of Potato Slices during Cold Storage (감자 슬라이스의 냉장 중 품질변화에 대한 침지용액과 예열처리의 영향)

  • 정현미;이귀주
    • Journal of the East Asian Society of Dietary Life
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    • v.6 no.3
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    • pp.325-333
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    • 1996
  • Potato slices were dipped in calcium choreide ar chitosan solutions or and preheated in each of these solutions. In order to prevent the quality deterioration while they were refrigerated for 4 weeks at 5$^{\circ}C$ Changes in degree of browning and other quality factors were determined while they were refrigerated for 4 weeks at 5$^{\circ}C$ During refrigeration, L values were decreased and optical density (A420) were increased. But L values were increased and A420 were decreased by dipping or preheating. The contents of vitamin C were decreased. however, the loss of vitmin C were the lowest in calcium chloride treaed potato slices(CaPS). And there were no combined effects of dipping and preheating during refrigeration. However, protein content of CaPS increased but that of other treated potato slices were decreased compared to that of control. With respect to changes in other physicochemical qualit, pH increased in chitosan treated potato slices(ChPS) and loss of weight was the lowest in combined with preheating. From these results, it was considered that the shelf-life of potato slices could be increased by dipping or-and preheating.

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Effect of chitosan coating combined with hypotaurine on the quality of shrimp (Litopenaeus vannamei) during storage

  • Chen, Meiyu;Hu, Lingping;Hu, Zhiheng;Zhou, Yaqi;Li, Gaoshang;Chin, Yaoxian;Hu, Yaqin
    • Fisheries and Aquatic Sciences
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    • v.25 no.2
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    • pp.64-75
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    • 2022
  • This study aimed to investigate the effect of different coating materials on the quality of shrimp (Litopenaeus vannamei) during chilled storage for 10 days. Fresh shrimp were randomly divided into five groups: the control group, the hypotaurine treatment group (2%), the chitosan group (1%), the hypotaurine + chitosan group (2% hypotaurine solution with 1% of chitosan), and the sodium metabisulfite treatment group (1.25%). Compared with other treatments, the lower accumulation of total visible counts (TVC, 5.25 Log10 CFU/g), total volatile basic nitrogen (TVB-N, 22.5 mg/100 g) and thiobarbituric acid values (TBA, 0.58 mg MDA/kg) suggested that coating of chitosan-hypotaurine could retard the microbial activity, protein degradation and lipid oxidation of shrimp. Meanwhile, results demonstrated that the chitosan coating combined with hypotaurine showed an excellent performance in inhibiting quality deterioration (pH 7.5, ∆E 7.0, hardness 393 g, and elasticity 0.69). Furthermore, the melanosis degree of shrimp was alleviated, and the sensory parameters, including appearance, odor and texture, were maintained to the acceptable level by chitosan based hypotaurine treatment during the chilled storage.

Combined application of Astragali Radix and chlorambucil on anticancerous effect and host safety in Lukemia Cell(P388D1 cell) and its bearing mice (황기와 Chlorambucil 병용(倂用)이 P388D1 백혈병(白血病) 세포(細胞) 및 담암(擔癌)생쥐에 미치는 영향(影響))

  • Jeon, Jeong-Hoi;Kim, Jin-Sung;Yoon, Sang-Hyub;Ryu, Bong-Ha;Ryu, Ki-Won
    • The Journal of Internal Korean Medicine
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    • v.26 no.2
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    • pp.291-301
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    • 2005
  • Objective : Anticancerous and host safety effects of the combination of Astragali Radix and chlorambucil are studied when it is applied to leukemia cell(P388D1 cell) related disease. Methods : After 5 groups of mice are treated by respective procedures (HG, CHL, HG+CHL, etc), the quantitative analyses (cell proliferation assay, mutagenesis test, survival rate, weight shift observation, tissue and blood analyses, etc) are conducted. Results : While sole injection of Astragali Radix extends the survival period and deter the liver and marrow function deterioration, combined injection (HG+CHL) shows more strong anticancerous effect than sole injection of Astragali Radix or Cholrambucil, and also does not cause any mutation on the normal cells and virulence on marrow and liver caused by leukemia. Conclusions : The combined application of Astragali Radix and chlorambucil has more effective anticancerous and host safety effects than independent use of them.

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The combined use of computer-guided, minimally invasive, flapless corticotomy and clear aligners as a novel approach to moderate crowding: A case report

  • Cassetta, Michele;Altieri, Federica;Pandolfi, Stefano;Giansanti, Matteo
    • The korean journal of orthodontics
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    • v.47 no.2
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    • pp.130-141
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    • 2017
  • The aim of this case report was to describe an innovative orthodontic treatment method that combined surgical and orthodontic techniques. The novel method was used to achieve a positive result in a case of moderate crowding by employing a computer-guided piezocision procedure followed by the use of clear aligners. A 23-year-old woman had a malocclusion with moderate crowding. Her periodontal indices, oral health-related quality of life (OHRQoL), and treatment time were evaluated. The treatment included interproximal corticotomy cuts extending through the entire thickness of the cortical layer, without a full-thickness flap reflection. This was achieved with a three-dimensionally printed surgical guide using computer-aided design and computer-aided manufacturing. Orthodontic force was applied to the teeth immediately after surgery by using clear appliances for better control of tooth movement. The total treatment time was 8 months. The periodontal indices improved after crowding correction, but the oral health impact profile showed a slight deterioration of OHRQoL during the 3 days following surgery. At the 2-year retention follow-up, the stability of treatment was excellent. The reduction in surgical time and patient discomfort, increased periodontal safety and patient acceptability, and accurate control of orthodontic movement without the risk of losing anchorage may encourage the use of this combined technique in appropriate cases.

Combined Effect of Granulocyte-Colony-Stimulating Factor-Induced Bone Marrow-Derived Stem Cells and Red Ginseng in Patients with Decompensated Liver Cirrhosis (Combined Effect of G-CSF and Red Ginseng in Liver Cirrhosis)

  • Kim, Hyun Hee;Kim, Seung Mo;Kim, Kyung Soon;Kwak, Min A;Kim, Sang Gyung;Kim, Byung Seok;Lee, Chang Hyeong
    • The Journal of Korean Medicine
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    • v.37 no.4
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    • pp.36-44
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    • 2016
  • Objectives: Granulocyte-colony-stimulating factor (G-CSF) mobilized bone marrow (BM)-derived hematopoietic stem cells could contribute to improvement of liver function. In addition, liver fibrosis can reportedly be prevented by the Rg 1 component of red ginseng. This study investigated the combined effect of G-CSF and red ginseng on decompensated liver cirrhosis. Methods: Four patients with decompensated liver cirrhosis were injected with G-CSF to proliferate BM stem cells for 4 days ($5{\mu}g/kg$ bid subcutaneously) and followed-up for 3 months. The patients also received red ginseng for 4 days (2 tablets tid per os). We analyzed Child-Pugh scores, Model for End-Stage Liver Disease (MELD) scores and cirrhotic complications. Results: All patients showed marked increases in White blood cell (WBC) and CD34+ cells in the peripheral blood, with a peak time of 4 days after G-CSF injection. Spleen size also increased after G-CSF injection, but not severely. At end of the study, 2 patients showed improvement in Child-Pugh scores, hepatic encephalopathy, and refractory ascites. During the clinical trial period, none of the 4 patients showed any other adverse events or deterioration of liver function. Conclusions: We conclude that G-CSF/red ginseng combination therapy is relatively effective in improving liver function and major complications of decompensated liver cirrhosis without adverse effects. Further clinical trials are warranted to assess the clinical effects of G-CSF for decompensated liver cirrhosis.

Properties of PD and Classification of Defect Patterns in Solid Insulation (고체절연체의 내부결함에 따른 부분방전 특성과 패턴분류)

  • Kang, S.H.;Park, Y.G.;Lee, K.W.;KiM, W.S.;Lee, Y.H.;Lim, K.J.
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1624-1626
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    • 1999
  • PD in defect of solid insulation system is very harmful since It often leads to deterioration of insulation by the combined action of the discharge ions bombarding the surface and the action of chemical compounds that are formed by the discharge. PD can indicate incipient failure, so it has been used to determine degradation of insulation. In this paper. we investigated PD in defects of solid insulation by using statical method and classified PD patterns with surface discharge, electrical tree and void discharge by using Kohonen network. we used peak charge, average discharge power, average discharge current, repetition rate, skewness, kurtosis, QN of the max pulse height vs. repetition rate $H_q(n)$ for analysis and classification.

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Removal Technologies of Odor and Volatile Organic Compounds from Industrial Processes (산업체 VOC/악취 저감기술)

  • Choo, Soo-Tae;Nam, Chang Mo
    • Journal of the Korean Society of Industry Convergence
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    • v.7 no.3
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    • pp.289-297
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    • 2004
  • Emissions of volatile organic compounds and odors from various industrial processes not only pollute surrounding life environments, but also lead to the deterioration of the working environments, causing various industrial health and business problems. These pollutants are usually stimulating, irritating, malodorous and sometimes carcinogenic, Which should be reduced in the pollutants formation, stage, but the practical processes do not allow This paper describes the major sources of VOC and odors, and their sampling/analysis methods. Furthermore, various removal technologies for these pollutants are suggested, which particularly include the characteristics of the catalytic and scrubber/carbon filter combined process, and even process design technologies.

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