• Title/Summary/Keyword: Parameter study

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Correlations Between the Physical Properties and Compression Index of KwangYang Clay (광양점토의 물리적 특성과 압축지수의 상관성)

  • Bae, Wooseok;Kim, Jongwoo
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.7
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    • pp.7-14
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    • 2009
  • The correlation equation empirically proposed to obtain compression indexes has been proposed to conveniently obtain the value using the soil parameter that can be obtained through simple tests when the number of time of consolidation testing is low or the distribution is large but most of the analyzed regions are limited to certain regions abroad or in the country and multiple data were integrated for use in many cases, thus it is not very reasonable to apply it. Therefore, to establish a new design method considering the uncertainty of the ground, it was selected the Kwangyang port area of which the data have been collected recently thus are relatively more reliable as the subject region of the study in order to maximally reduce the uncertainty of test data. After performing the verification of the normality of the consolidation test data obtained from the selected region and the transformation of variables, a prediction formula was proposed through the regression model with the transformed variables and the proposed regression model with transformed variables was compared with existing empirical equations to verify the suitability of the proposed model formula. After analyzing, it was confirmed that the coefficient of determination was increased after the Box-Cox variable transformation, thus the explanatory power was being enhanced and through the root-mean-square-error method, it was confirmed that the proposed model formula showed the most closed value to the test value.

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Experimental Study on the Unsaturated Characteristics of Dredging Soils at Saemangeum Area (새만금지역 준설토의 불포화 특성에 대한 실험적 연구)

  • Song, Young-Suk;You, Seung-Kyong
    • Journal of the Korean Geosynthetics Society
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    • v.10 no.3
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    • pp.25-32
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    • 2011
  • The matric suction and volumetric water content of dredging soils obtained from Saemangeum area were measured by the automated Soil-Water Characteristic Curve (SWCC) apparatus under both drying and wetting conditions. Based on the test result, SWCCs of the dredging soils were estimated by the van Genuchten(1980) model. The matric suction of drying process is larger than that of wetting process at a same effective degree of saturation. The suction stresses for various matirc suctions were estimated using Lu and Likos(2006) model and the Suction Stress Characteristic Curves (SSCC) were predicted using the independent parameter of SWCC. The suction stress of drying path was increased and decreased, while the suction stress of wetting path was continuously decreased with increasing the effective degree. Also, the suction stress of drying path is larger than that of wetting path at a same effective degree of saturation. The Hydraulic Conductivity Function(HCF) was also predicted by the van Genuchten(1980) model. The hydraulic conductivity was increased with increasing the volumetric water content. The hydraulic conductivity of drying path is larger than that of wetting path at a same matric suction. According to the results of SWCCs and SSCCs, the hysteresis phenomenon of suction stress or matric suction during both drying and wetting paths was occurred. The main reason of hysteresis phenomenon is a ink bottle effect of water among soil particles.

Semi-active storey isolation system employing MRE isolator with parameter identification based on NSGA-II with DCD

  • Gu, Xiaoyu;Yu, Yang;Li, Jianchun;Li, Yancheng;Alamdari, Mehrisadat Makki
    • Earthquakes and Structures
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    • v.11 no.6
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    • pp.1101-1121
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    • 2016
  • Base isolation, one of the popular seismic protection approaches proven to be effective in practical applications, has been widely applied worldwide during the past few decades. As the techniques mature, it has been recognised that, the biggest issue faced in base isolation technique is the challenge of great base displacement demand, which leads to the potential of overturning of the structure, instability and permanent damage of the isolators. Meanwhile, drain, ventilation and regular maintenance at the base isolation level are quite difficult and rather time- and fund- consuming, especially in the highly populated areas. To address these challenges, a number of efforts have been dedicated to propose new isolation systems, including segmental building, additional storey isolation (ASI) and mid-storey isolation system, etc. However, such techniques have their own flaws, among which whipping effect is the most obvious one. Moreover, due to their inherent passive nature, all these techniques, including traditional base isolation system, show incapability to cope with the unpredictable and diverse nature of earthquakes. The solution for the aforementioned challenge is to develop an innovative vibration isolation system to realise variable structural stiffness to maximise the adaptability and controllability of the system. Recently, advances on the development of an adaptive magneto-rheological elastomer (MRE) vibration isolator has enlightened the development of adaptive base isolation systems due to its ability to alter stiffness by changing applied electrical current. In this study, an innovative semi-active storey isolation system inserting such novel MRE isolators between each floor is proposed. The stiffness of each level in the proposed isolation system can thus be changed according to characteristics of the MRE isolators. Non-dominated sorting genetic algorithm type II (NSGA-II) with dynamic crowding distance (DCD) is utilised for the optimisation of the parameters at isolation level in the system. Extensive comparative simulation studies have been conducted using 5-storey benchmark model to evaluate the performance of the proposed isolation system under different earthquake excitations. Simulation results compare the seismic responses of bare building, building with passive controlled MRE base isolation system, building with passive-controlled MRE storey isolation system and building with optimised storey isolation system.

EFFECTS OF CIMATEROL (CL 263,780) ON GROWTH PERFORMANCE AND CARCASS QUALITY OF BROILERS FED ON DIFFERENT LEVELS OF DIETARY PROTEIN AND ENERGY

  • Kim, Y.Y.;Han, I.K.;Ha, J.K.;Choi, Y.J.;Lee, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.4 no.4
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    • pp.383-393
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    • 1991
  • The present study was carried out to investigate the effect of cimaterol on growth performance, carcass quality and cellular functional activity of broilers as affected by the various protein and energy levels. In starter period (0-21 days) all chicks were fed the basal diet which contained approximately 23 % crude protein and 3200 kcal of metabolizable energy per kg of diet. The cimaterol was added during 22-49 days and during the period of 8th week the cimaterol was withdrawn. In finisher period (22-49 days), a $2{\times}2{\times}3$ factorial arrangement consisting of 2 levels of cimaterol (0 mg/kg, 0.25 mg/kg), 2 levels of protein (19%, 17%) and 3 levels of energy (3200, 2900, 2600 kcal/kg) was used. In the finisher period, the body weight gain and feed efficiency was improved by the supplementation of cimaterol. The high protein and high energy level with supplementation of cimaterol had showed the highest body weight gain and feed efficiency, without significant difference. The administration of cimaterol had no effects on percentage of abdominal fat content, giblet and neck. Eventhough the difference was not significant (p>0.05), carcass yield was improved slightly by the administration of cimaterol. The effect of cimaterol on carcass composition was clearly demonstrated that protein content of broilers was not increased (p>0.05) but fat content decreased significantly (p<0.05). The ultilization of nutrients in experimental diets was not significantly affected by feeding cimaterol compared to control group. The results of in vitro studies with liver and adipose tissue showed that cimaterol increased the lipolytic activities at 19% protein level whereas at 17% protein level this effect was variable. Lipogenic activities in liver and adipose tissue were not affected with the administration of cimaterol but the activities increased as energy decreased, particularly in liver tissue. In cell studies with acinar culture of liver tissues, cimaterol had no effect on protein synthetic activity but the parameter was increased at higher level of dietary protein and energy. Protein secretion in liver was increased by the supplementation of cimaterol. In addition, at high protein level the protein secretion was increased and has shown the highest values at medium energy level.

Genetic Parameter Estimation in Seedstock Swine Population for Growth Performances

  • Choi, Jae Gwan;Cho, Chung Il;Choi, Im Soo;Lee, Seung Soo;Choi, Tae Jeong;Cho, Kwang Hyun;Park, Byoung Ho;Choy, Yun Ho
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.4
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    • pp.470-475
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    • 2013
  • The objective of this study was to estimate genetic parameters that are to be used for across-herd genetic evaluations of seed stock pigs at GGP level. Performance data with pedigree information collected from swine breeder farms in Korea were provided by Korea Animal Improvement Association (AIAK). Performance data were composed of final body weights at test days and ultrasound measures of back fat thickness (BF), rib eye area (EMA) and retail cut percentage (RCP). Breeds of swine tested were Landrace, Yorkshire and Duroc. Days to 90 kg body weight (DAYS90) were estimated with linear function of age and ADG calculated from body weights at test days. Ultrasound measures were taken with A-mode ultrasound scanners by trained technicians. Number of performance records after censoring outliers and keeping records pigs only born from year 2000 were of 78,068 Duroc pigs, 101,821 Landrace pigs and 281,421 Yorkshire pigs. Models included contemporary groups defined by the same herd and the same seasons of births of the same year, which was regarded as fixed along with the effect of sex for all traits and body weight at test day as a linear covariate for ultrasound measures. REML estimation was processed with REMLF90 program. Heritability estimates were 0.40, 0.32, 0.21 0.39 for DAYS90, ADG, BF, EMA, RCP, respectively for Duroc population. Respective heritability estimates for Landrace population were 0.43, 0.41, 0.22, and 0.43 and for Yorkshire population were 0.36, 0.38, 0.22, and 0.42. Genetic correlation coefficients of DAYS90 with BF, EMA, or RCP were estimated to be 0.00 to 0.09, -0.15 to -0.25, 0.22 to 0.28, respectively for three breeds populations. Genetic correlation coefficients estimated between BF and EMA was -0.33 to -0.39. Genetic correlation coefficient estimated between BF and RCP was high and negative (-0.78 to -0.85) but the environmental correlation coefficients between these two traits was medium and negative (near -0.35), which describes a highly correlated genetic response to selection on one or the other of these traits. Genetic Trends of all three breeds tend to be towards bigger EMA or greater RCP and shorter DAYS90 especially from generations born after year 2000.

Economic Evaluation and Budget Impact Analysis of the Surveillance Program for Hepatocellular Carcinoma in Thai Chronic Hepatitis B Patients

  • Sangmala, Pannapa;Chaikledkaew, Usa;Tanwandee, Tawesak;Pongchareonsuk, Petcharat
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.20
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    • pp.8993-9004
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    • 2014
  • Background: The incidence rate and the treatment costs of hepatocellular carcinoma (HCC) are high, especially in Thailand. Previous studies indicated that early detection by a surveillance program could help by down-staging. This study aimed to compare the costs and health outcomes associated with the introduction of a HCC surveillance program with no program and to estimate the budget impact if the HCC surveillance program were implemented. Materials and Methods: A cost utility analysis using a decision tree and Markov models was used to compare costs and outcomes during the lifetime period based on a societal perspective between alternative HCC surveillance strategies with no program. Costs included direct medical, direct non-medical, and indirect costs. Health outcomes were measured as life years (LYs), and quality adjusted life years (QALYs). The results were presented in terms of the incremental cost-effectiveness ratio (ICER) in Thai THB per QALY gained. One-way and probabilistic sensitivity analyses were applied to investigate parameter uncertainties. Budget impact analysis (BIA) was performed based on the governmental perspective. Results: Semi-annual ultrasonography (US) and semi-annual ultrasonography plus alpha-fetoprotein (US plus AFP) as the first screening for HCC surveillance would be cost-effective options at the willingness to pay (WTP) threshold of 160,000 THB per QALY gained compared with no surveillance program (ICER=118,796 and ICER=123,451 THB/QALY), respectively. The semi-annual US plus AFP yielded more net monetary benefit, but caused a substantially higher budget (237 to 502 million THB) than semi-annual US (81 to 201 million THB) during the next ten fiscal years. Conclusions: Our results suggested that a semi-annual US program should be used as the first screening for HCC surveillance and included in the benefit package of Thai health insurance schemes for both chronic hepatitis B males and females aged between 40-50 years. In addition, policy makers considered the program could be feasible, but additional evidence is needed to support the whole prevention system before the implementation of a strategic plan.

Roles of Sonography and Hysteroscopy in the Detection of Premalignant and Malignant Polyps in Women Presenting with Postmenopausal Bleeding and Thickened Endometrium

  • Cavkaytar, Sabri;Kokanali, Mahmut Kuntay;Ceran, Ufuk;Topcu, Hasan Onur;Sirvan, Levent;Doganay, Melike
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.13
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    • pp.5355-5358
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    • 2014
  • Background: To assess the role of sonographic endometrial thickness and hysteroscopic polyp size in predicting premalignant and malignant polyps in postmenopausal women. Materials and Methods: A total of 328 postmenopausal women with abnormal uterine bleeding and thickened endometrium underwent operative hysteroscopy due to detection of endometrial polyps were included in this retrospective study. Preoperative endometrial thickness measured by transvaginal ultrasonography and polyp size on hysteroscopy were noted. Hysteroscopic resection with histology was performed for endometrial polyps. Endometrial thickness and polyp size were evaluated on the basis of final diagnosis established by histologic examination. Receiver operator characteristic curves were calculated to assess the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of endometrial thickness and polyp size for detecting pemalignant and malignant polyps. Results: Premalignant and malignant polyps were identified in 26 (7.9%) of cases. Sonographic measurement showed a greater endometrial thickness in cases of premalignant and malignant polyps when compared to benign polyps. On surgical hysteroscopy, premalignant and malignant polyps were also larger. Endometrial thickness demonstrated a sensitivity of 53.8%, specificity of 85.8%, PPV of 24.6% and NPV of 95.6% at a cut-off limit of 11.5 mm with diagnostic accuracy of 83.2%. Polyp size has a diagnostic accuracy of 94.8% with a sensitivity of 92.3%, specificity of 95.0%, PPV of 61.5% and NPV of 99.3% at a cut-off point of 19.5mm. Conclusions: Endometrial thickness measured by transvaginal ultrasonography is not sufficient in predicting premalignant and malignant endometrial polyps in postmenopausal women with abnormal uterine bleeding and thickened endometrium. Polyp size on hysteroscopy is a more accurate parameter, because of better sensitivity and specificity. However, while polyp size ${\geq}19.5mm$ seems to have a great accuracy for predicting premalignancy and malignancy, histologic evaluation is still necessary to exclude premalignant and malignant polyps.

Reinterpretation of the protein identification process for proteomics data

  • Kwon, Kyung-Hoon;Lee, Sang-Kwang;Cho, Kun;Park, Gun-Wook;Kang, Byeong-Soo;Park, Young-Mok
    • Interdisciplinary Bio Central
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    • v.1 no.3
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    • pp.9.1-9.6
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    • 2009
  • Introduction: In the mass spectrometry-based proteomics, biological samples are analyzed to identify proteins by mass spectrometer and database search. Database search is the process to select the best matches to the experimental mass spectra among the amino acid sequence database and we identify the protein as the matched sequence. The match score is defined to find the matches from the database and declare the highest scored hit as the most probable protein. According to the score definition, search result varies. In this study, the difference among search results of different search engines or different databases was investigated, in order to suggest a better way to identify more proteins with higher reliability. Materials and Methods: The protein extract of human mesenchymal stem cell was separated by several bands by one-dimensional electrophorysis. One-dimensional gel was excised one by one, digested by trypsin and analyzed by a mass spectrometer, FT LTQ. The tandem mass (MS/MS) spectra of peptide ions were applied to the database search of X!Tandem, Mascot and Sequest search engines with IPI human database and SwissProt database. The search result was filtered by several threshold probability values of the Trans-Proteomic Pipeline (TPP) of the Institute for Systems Biology. The analysis of the output which was generated from TPP was performed. Results and Discussion: For each MS/MS spectrum, the peptide sequences which were identified from different conditions such as search engines, threshold probability, and sequence database were compared. The main difference of peptide identification at high threshold probability was caused by not the difference of sequence database but the difference of the score. As the threshold probability decreases, the missed peptides appeared. Conversely, in the extremely high threshold level, we missed many true assignments. Conclusion and Prospects: The different identification result of the search engines was mainly caused by the different scoring algorithms. Usually in proteomics high-scored peptides are selected and low-scored peptides are discarded. Many of them are true negatives. By integrating the search results from different parameter and different search engines, the protein identification process can be improved.

Determination of Ecological Flow at the Confluence of Nakdong River and Gumho River Using River2D (River2D를 이용한 낙동강-금호강 합류부의 생태유량 산정)

  • Seo, Il Won;Park, Inhwan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.3
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    • pp.947-956
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    • 2013
  • In this study, WUA (Weighted Usable Area) was calculated to determine ecological flow at the confluence of Nakdong River and Gumho River by using River2D. To calibrate River2D, simulation results of River2D were compared with calibrated HEC-RAS simulation results and the optimum parameters were determined. After parameter calibration, WUA of Zacco platypus and Zacco temmincki which are dominant species in Nakdong River was calculated with changing upstream flowrate. From the result, WUA is changed according to flowrate and growth stage. In the flowrate-WUA/A graph, ecological flow can be determined as $33.3m^3/s{\sim}39.96m^3/s$ in Nakdong River and $3.6m^3/s{\sim}4.32m^3/s$ in Gumho River. After dredging for Four major rivers restoration project, WUA of Zacco platypus and Zacco temmincki were calculated by using the ecological flow. The results show that WUA after dredging are decreased when compared with undredged condition. WUA of Common carp is 2~3 times bigger than WUA of Zacco platypus and Zacco temmincki at the dredged condition in Nakdong River.

Differentiation between Glioblastoma and Primary Central Nervous System Lymphoma Using Dynamic Susceptibility Contrast-Enhanced Perfusion MR Imaging: Comparison Study of the Manual versus Semiautomatic Segmentation Method

  • Kim, Ye Eun;Choi, Seung Hong;Lee, Soon Tae;Kim, Tae Min;Park, Chul-Kee;Park, Sung-Hye;Kim, Il Han
    • Investigative Magnetic Resonance Imaging
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    • v.21 no.1
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    • pp.9-19
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    • 2017
  • Background: Normalized cerebral blood volume (nCBV) can be measured using manual or semiautomatic segmentation method. However, the difference in diagnostic performance on brain tumor differentiation between differently measured nCBV has not been evaluated. Purpose: To compare the diagnostic performance of manually obtained nCBV to that of semiautomatically obtained nCBV on glioblastoma (GBM) and primary central nervous system lymphoma (PCNSL) differentiation. Materials and Methods: Histopathologically confirmed forty GBM and eleven PCNSL patients underwent 3T MR imaging with dynamic susceptibility contrast-enhanced perfusion MR imaging before any treatment or biopsy. Based on the contrast-enhanced T1-weighted imaging, the mean nCBV (mCBV) was measured using the manual method (manual mCBV), random regions of interest (ROIs) placement by the observer, or the semiautomatic segmentation method (semiautomatic mCBV). The volume of enhancing portion of the tumor was also measured during semiautomatic segmentation process. T-test, ROC curve analysis, Fisher's exact test and multivariate regression analysis were performed to compare the value and evaluate the diagnostic performance of each parameter. Results: GBM showed a higher enhancing volume (P = 0.0307), a higher manual mCBV (P = 0.018) and a higher semiautomatic mCBV (P = 0.0111) than that of the PCNSL. Semiautomatic mCBV had the highest value (0.815) for the area under the curve (AUC), however, the AUCs of the three parameters were not significantly different from each other. The semiautomatic mCBV was the best independent predictor for the GBM and PCNSL differential diagnosis according to the stepwise multiple regression analysis. Conclusion: We found that the semiautomatic mCBV could be a better predictor than the manual mCBV for the GBM and PCNSL differentiation. We believe that the semiautomatic segmentation method can contribute to the advancement of perfusion based brain tumor evaluation.