• Title/Summary/Keyword: partial changes

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Laboratory investigations on the effects of acid attack on concrete containing portland cement partially replaced with ambient-cured alkali-activated binders

  • Ramagiri, Kruthi K.;Patil, Swaraj;Mundra, Harsh;Kar, Arkamitra
    • Advances in concrete construction
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    • v.10 no.3
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    • pp.221-236
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    • 2020
  • To reduce the CO2 emissions associated with the manufacture of portland cement (PC), an efficient alternative like an alkali-activated binder (AAB) is the requirement of the industry. To promote the use of AAB in construction activities, a practically implementable mix proportion is required. Owing to the several raw ingredients of AAB concrete and their associated uncertainties, partial replacement of PC by AAB may be adopted instead of complete replacement as per industrial requirements. Hence, the present study aims to determine an optimal proportion for partial replacement of PC with AAB and recommend a technique for it based on site conditions. Three modes of partial replacement are followed: combining all the dry ingredients for AAB and PC followed by the addition of the requisite liquids (PAM); combining the PC and the AAB concrete in two horizontal layers (PAH); and two vertical layers (PAV). 28-day old specimens are exposed to 10% v/v solutions of HCl, H2SO4, and HNO3 to evaluate changes in mechanical, physical, and microstructural characteristics through compressive strength, corrosion depth, and microscopy. Based on deterioration in strength and integrity, PAH or PAV can be adopted in absence of acid attack, whereas PAM is recommended in presence of acid attack.

The Development of a Fault Diagnosis Model based on the Parameter Estimations of Partial Least Square Models (부분최소제곱법 모델의 파라미터 추정을 이용한 화학공정의 이상진단 모델 개발)

  • Lee, Kwang Oh;Lee, Chang Jun
    • Journal of the Korean Society of Safety
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    • v.34 no.4
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    • pp.59-67
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    • 2019
  • Since it is really hard to construct process models based on prior process knowledges, various statistical approaches have been employed to build fault diagnosis models. However, the crucial drawback of these approaches is that the solutions may vary according to the fault magnitude, even if the same fault occurs. In this study, the parameter monitoring approach is suggested. When a fault occurs in a chemical process, this leads to trigger the change of a process model and the monitoring parameters of process models is able to provide the efficient fault diagnosis model. A few important variables are selected and their predictive models are constructed by partial least square (PLS) method. The Euclidean norms of parameters of PLS models are estimated and a fault diagnosis can be performed as comparing with parameters of PLS models based on normal operational conditions. To improve the monitoring performance, cumulative summation (CUSUM) control chart is employed and the changes of model parameters are recorded to identify the type of an unknown fault. To verify the efficacy of the proposed model, Tennessee Eastman (TE) process is tested and this model can be easily applied to other complex processes.

A model experiment of damage detection for offshore jacket platforms based on partial measurement

  • Shi, Xiang;Li, Hua-Jun;Yang, Yong-Chun;Gong, Chen
    • Structural Engineering and Mechanics
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    • v.29 no.3
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    • pp.311-325
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    • 2008
  • Noting that damage occurrence of offshore jacket platforms is concentrated in two structural regions that are in the vicinity of still water surface and close to the seabed, a damage detection method by using only partial measurement of vibration in a suspect region was presented in this paper, which can not only locate damaged members but also evaluate damage severities. Then employing an experiment platform model under white-noise ground excitation by shaking table and using modal parameters of the first three modes identified by a scalar-type ARMA method on undamaged and damaged structures, the feasibility of the damage detection method was discussed. Modal parameters from eigenvalue analysis on the structural FEM model were also used to help the discussions. It is demonstrated that the damage detection algorithm is feasible on damage location and severity evaluation for broken slanted braces and it is robust against the errors of baseline FEM model to real structure when the principal errors is formed by difference of modal frequencies. It is also found that Z-value changes of modal shapes also play a role in the precise detection of damage.

Estimating Import Demand Function for the United States

  • Yoon, Il-Hyun;Kim, Yong-Min
    • Asia-Pacific Journal of Business
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    • v.10 no.2
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    • pp.13-26
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    • 2019
  • This paper aims to empirically examine the short-run and long-run aggregate demand for the US imports using quarterly economic data for the period 2000-2018 including aggregate imports, final expenditure components, gross fixed capital formation and relative price of imports. According to the results of both multivariate co-integration analysis and error correction model, the above variables are all cointegrated and significant differences are found to exist among the long-run partial elasticities of imports as regards different macro components of final expenditure. Partial elasticities with respect to government expenditure, gross fixed capital formation, exports and relative price of import are found to be positive while imports seems to respond negatively to changes in private consumption, implying that an increase in private consumption could result in a significant reduction in demand for imports in the long run. With regard to the relative import prices, the results appear to indicate a relatively insignificant influence on the aggregate imports in the US in the long run. However, an error correction model designed for predicting the short-term variability shows that only exports have an impact on the imports in the short run.

Simulation of Characteristics Analysis by Total Ionizing Dose Effects in Partial Isolation Buried Channel Array Transistor (부분분리 매립 채널 어레이 트랜지스터의 총 이온화 선량 영향에 따른 특성 해석 시뮬레이션)

  • Je-won Park;Myoung-Jin Lee
    • Journal of IKEEE
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    • v.27 no.3
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    • pp.303-307
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    • 2023
  • In this paper, the creation of an Electron-Hole Pair due to Total Ionizing Dose (TID) effects inside the oxide of a Buried Channel Array Transistor (BCAT) device is induced, resulting in an increase in leakage current and threshold due to an increase in hole trap charge at the oxide interface. By comparing and simulating changes in voltage with the previously proposed Partial Isolation Buried Channel Array Transistor (Pi-BCAT) structure, the characteristics in leakage current and threshold voltage changed regardless of the increased oxide area of the Pi-BCAT device, compared to the asymmetrically doped BCAT structure. It shows superiority.

Efficacy of Integrated Korean Medicines in the Treatment of Partial Triangular Fibrocartilage Complex Tears: A Case Report

  • Jae-Joon Ha;Myeong-Yeol Yang;Ji-Sun Kim;Hong-Wook Choi;Gyu-Bin Lee;Dong-Ju Yoon;Dong-Jin Kim;Do-Young Kim
    • Journal of Acupuncture Research
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    • v.40 no.4
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    • pp.382-388
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    • 2023
  • The triangular fibrocartilage complex (TFCC) is crucial for stabilizing the ulnar side of the wrist but can be partially torn due to degenerative changes, falling, or sudden injuries. However, only a few studies have focused on the use of Korean medicine treatments for TFCC-related wrist pain. This case report presents the successful outcomes of integrated Korean medicine treatment in a patient with a partial TFCC tear. The diagnosis was confirmed via magnetic resonance imaging, which revealed the tear. Subsequently, the patient received integrated Korean medicine treatments. The assessment of the pain scale scores revealed a significant reduction in wrist pain and an improvement in daily life activities. Based on the findings of this study, integrated Korean medicine treatments have been proven to be an effective treatment option for patients with a partial TFCC tear. However, further research is needed to determine the potential benefits and mechanisms of these treatments in managing TFCC-related wrist pain.

Thermodynamic properties and structural geometry of KMgCl3·6H2O single crystals

  • Yoon, Hyo In;Lim, Ae Ran
    • Journal of the Korean Magnetic Resonance Society
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    • v.19 no.3
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    • pp.119-123
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    • 2015
  • The thermodynamic properties and structural geometry of $KMgCl_3{\cdot}6H_2O$ were investigated using thermogravimetric analysis, differential scanning calorimetry, and nuclear magnetic resonance. The initial mass loss occurs around 351 K ($=T_d$), which is interpreted as the onset of partial thermal decomposition. Phase transition temperatures were found at 435 K ($=T_{C1}$) and 481 K ($=T_{C2}$). The temperature dependences of the spin-lattice relaxation time $T_1$ for the $^1H$ nucleus changes abruptly near $T_{C1}$. These changes are associated with changes in the geometry of the arrangement of octahedral water molecules.

Changes in Adhesion Interface between Rubber and Steel Cord with Aging Treatment (열화처리에 따른 고무와 강선코드간 접착계면의 변화)

  • Seo, Gon;Sohn, Bongyoung
    • Applied Chemistry for Engineering
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    • v.5 no.4
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    • pp.630-636
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    • 1994
  • The changes in adhesion interface between rubber compound and brass plated steel cord after various aging treatments were studied by using an Auger electron spectrometer and a scanning electron microscope. After thermal aging, partial oxidation and additional growth of adhesion layer were observed. The adhesion layer and brass were partially removed after humid aging. With dynamic aging the adhesion layer was destroyed and the corrosion of steel core was proceeded. The changes in adhesion interface were discussed in terms of the adhesion properties determined from the stress-strain experiments.

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Compensation of Variation from Long-Term Spectral Measurement for Non-invasive Blood Glucose in Mouse by Near-Infrared Spectroscopy (근적외분광분석법을 이용한 생쥐꼬리에서의 비침습 혈당 정량시 장기간 측정에 따른 변이 요인의 보정)

  • 백주현;강나루;우영아;김효진
    • YAKHAK HOEJI
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    • v.48 no.3
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    • pp.177-181
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    • 2004
  • Non-invasive blood glucose measurement from mouse tail was performed by near-infrared (NIR) spectroscopy. Three groups; normal, type I diabetes (insulin dependent diabetes mellitus, IDDM), type II diabetes (non-insulin dependent diabetes mellitus, NIDDM) group, were studied over a 10 weeks period with the collection of near-infrared (NIR) spectra. Spectral variations from long-term measurement (10 weeks) from dramatic and nonlinear changes in the optical properties of the live tissue sample were compensated by chemometrics techniques such as principle component analysis (PCA) and partial least squares (PLS) regression. The effect from mouse body temperature changes on NIR spectral data was also considered. This study showed that the compensation of variations from long-term measurement and temperature changes improved calibration accuracy of non-invasive blood glucose measurement.

Changes in the $Ca^{2+}$-, $Mg^{2+}$- dependent Adenosine Triphosphatase Activity and Ultrastructure of Marine Fishes by Partial Freezing II. Changes in ATPase Activity of Yellowtail Actomyosin during Cold Storage (해산어의 부분동결에 의한 $Ca^{2+}$-, $Mg^{2+}$- dependent Adenosine Triphosphatase 활성 및 근섬유의 미세구조 변화 II. 저온저장에 의한 방어 Actomyosin ATPase의 활성변화)

  • 박찬성;최경호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.19 no.4
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    • pp.349-355
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    • 1990
  • Actomyosine prepared from Yellowtail fish(seriola quinqueradiata) were stored at $0^{\circ}C$(ice-cooling) -3.5$^{\circ}C$(partial freeaing) and -2$0^{\circ}C$(freezing) Another actomyosin samples were prepared from the fish previously stored at the temperatures for a week as the maximum .Remaining activity of {{{{ {Ca }^{2+ } }}}}-and {{{{ {Mg }^{2+ } }}}}- dependent adenosine triphosphatase(ATPase) activity was measured fronm the actomyosin preparations. Specific activity of {{{{ {Mg }^{2+ } }}}}-ATPase of actomy-osin before storagew was 0.253$\mu$ mole pi/min/mg of protein and it was 1.5 times higher than that of {{{{ {Ca }^{2+ } }}}} -ATPase. The enzyme activities were markedly decreased during early period of storage. However no significant differences in the enzyme activity were revealed among the samples stored at different temperature. The enzyme of actomyosin prepared from the fish previously stored at the temperatures for a week revealed an acitivity of 2-3 times higher than that of freezing. Apparent denaturation constant of {{{{ {Mg }^{2+ } }}}} -ATPase of actomyosin was between 0.810-1.139 per day and it was about 1.5 times hgiher than that of {{{{ {Ca }^{2+ } }}}} -ATPase. But the constant of {{{{ {Mg }^{2+ } }}}} ATPase of actomyosin extracted from the fist stored for a week at each temperature was between 0.176-0.356 per day. This constant was 4 times higher than that of {{{{ {Ca }^{2+ } }}}}- ATPase in frozen stored fish. It was presumed from these results that denaturation of ATPase is largely accorded to the structural changes of actomyosin.

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