• Title/Summary/Keyword: Variable Parameter

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A correlation analysis between state variables of rainfall-runoff model and hydrometeorological variables (강우-유출 모형의 상태변수와 수문기상변량과의 상관성 분석)

  • Shim, Eunjeung;Uranchimeg, Sumiya;Lee, Yearin;Moon, Young-Il;Lee, Joo-Heon;Kwon, Hyun-Han
    • Journal of Korea Water Resources Association
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    • v.54 no.12
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    • pp.1295-1304
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    • 2021
  • For the efficient use and management of water resources, a reliable rainfall-runoff analysis is necessary. Still, continuous hydrological data and rainfall-runoff data are insufficient to secure through measurements and models. In particular, as part of the reasonable improvement of a rainfall-runoff model in the case of an ungauged watershed, regionalization is being used to transfer the parameters necessary for the model application to the ungauged watershed. In this study, the GR4J model was selected, and the SCEM-UA method was used to optimize parameters. The rainfall-runoff model for the analysis of the correlation between watershed characteristics and parameters obtained through the model was regionalized by the Copula function, and rainfall-runoff analysis with the regionalized parameters was performed on the ungauged watershed. In the process, the intermediate state variables of the rainfall-runoff model were extracted, and the correlation analysis between water level and the ground water level was investigated. Furthermore, in the process of rainfall-runoff analysis, the Standardized State variable Drought Index (SSDI) was calculated by calculating and indexing the state variables of the GR4J model. and the calculated SSDI was compared with the standardized Precipitation index (SPI), and the hydrological suitability evaluation of the drought index was performed to confirm the possibility of drought monitoring and application in the ungauged watershed.

Coordinative movement of articulators in bilabial stop /p/

  • Son, Minjung
    • Phonetics and Speech Sciences
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    • v.10 no.4
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    • pp.77-89
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    • 2018
  • Speech articulators are coordinated for the purpose of segmental constriction in terms of a task. In particular, vertical jaw movements repeatedly contribute to consonantal as well as vocalic constriction. The current study explores vertical jaw movements in conjunction with bilabial constriction in bilabial stop /p/ in the context /a/-to-/a/. Revisiting kinematic data of /p/ collected using the electromagenetic midsagittal articulometer (EMMA) method from seven (four female and three male) speakers of Seoul Korean, we examined maximum vertical jaw position, its relative timing with respect to the upper and lower lips, and lip aperture minima. The results of those dependent variables are recapitulated in terms of linguistic (different word boundaries) and paralinguistic (different speech rates) factors as follows. Firstly, maximum jaw height was lower in the across-word boundary condition (across-word < within-word), but it did not differ as a function of different speech rates (comfortable = fast). Secondly, more reduction in the lip aperture (LA) gesture occurred in fast rate, while word-boundary effects were absent. Thirdly, jaw raising was still in progress after the lips' positional extrema were achieved in the within-word condition, while the former was completed before the latter in the across-word condition. Lastly, relative temporal lags between the jaw and the lips (UL and LL) were more synchronous in fast rate, compared to comfortable rate. When these results are considered together, it is possible to posit that speakers are not tolerant of lenition to the extent that it is potentially realized as a labial approximant in either word-boundary condition while jaw height still manifested lower jaw position in the across-word boundary condition. Early termination of vertical jaw maxima before vertical lower lip maxima across-word condition may be partly responsible for the spatial reduction of jaw raising movements. This may come about as a consequence of an excessive number of factors (e.g., upper lip height (UH), lower lip height (LH), jaw angle (JA)) for the representation of a vector with two degrees of freedom (x, y) engaged in a gesture-based task (e.g., lip aperture (LA)). In the task-dynamic application toolkit, the jaw angle parameter can be assigned numerical values for greater weight in the across-word boundary condition, which in turn gives rise to lower jaw position. Speech rate-dependent spatial reduction in lip aperture may be able to be resolved by means of manipulating activation time of an active tract variable in the gestural score level.

A Study of Soil Moisture Retention Relation using Weather Radar Image Data

  • Choi, Jeongho;Han, Myoungsun;Lim, Sanghun;Kim, Donggu;Jang, Bong-joo
    • Journal of Multimedia Information System
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    • v.5 no.4
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    • pp.235-244
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    • 2018
  • Potential maximum soil moisture retention (S) is a dominant parameter in the Soil Conservation Service (SCS; now called the USDA Natural Resources Conservation Service (NRCS)) runoff Curve Number (CN) method commonly used in hydrologic modeling for event-based flood forecasting (SCS, 1985). Physically, S represents the depth [L] soil could store water through infiltration. The depth of soil moisture retention will vary depending on infiltration from previous rainfall events; an adjustment is usually made using a factor for Antecedent Moisture Conditions (AMCs). Application of the method for continuous simulation of multiple storms has typically involved updating the AMC and S. However, these studies have focused on a time step where S is allowed to vary at daily or longer time scales. While useful for hydrologic events that span multiple days, this temporal resolution is too coarse for short-term applications such as flash flood events. In this study, an approach for deriving a time-variable potential maximum soil moisture retention curve (S-curve) at hourly time-scales is presented. The methodology is applied to the Napa River basin, California. Rainfall events from 2011 to 2012 are used for estimating the event-based S. As a result, we derive an S-curve which is classified into three sections depending on the recovery rate of S for soil moisture conditions ranging from 1) dry, 2) transitional from dry to wet, and 3) wet. The first section is described as gradually increasing recovering S (0.97 mm/hr or 23.28 mm/day), the second section is described as steeply recovering S (2.11 mm/hr or 50.64 mm/day) and the third section is described as gradually decreasing recovery (0.34 mm/hr or 8.16 mm/day). Using the S-curve, we can estimate the hourly change of soil moisture content according to the time duration after rainfall cessation, which is then used to estimate direct runoff for a continuous simulation for flood forecasting.

Cut-off Value for Body Mass Index in Predicting Surgical Success in Patients with Lumbar Spinal Canal Stenosis

  • Azimi, Parisa;Yazdanian, Taravat;Shahzadi, Sohrab;Benzel, Edward C.;Azhari, Shirzad;Aghaei, Hossein Nayeb;Montazeri, Ali
    • Asian Spine Journal
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    • v.12 no.6
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    • pp.1085-1091
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    • 2018
  • Study Design: Case-control. Purpose: To determine optimal cut-off value for body mass index (BMI) in predicting surgical success in patients with lumbar spinal canal stenosis (LSCS). Overview of Literature: BMI is an essential variable in the assessment of patients with LSCS. Methods: We conducted a prospective study with obese and non-obese LSCS surgical patients and analyzed data on age, sex, duration of symptoms, walking distance, morphologic grade of stenosis, BMI, postoperative complications, and functional disability. Obesity was defined as BMI of ${\geq}30kg/m^2$. Patients completed the Oswestry Disability Index (ODI) questionnaire before surgery and 2 years after surgery. Surgical success was defined as ${\geq}30%$ improvement from the baseline ODI score. Receiver operating characteristic (ROC) analysis was used to estimate the optimal cut-off values of BMI to predict surgical success. In addition, correlation was assessed between BMI and stenosis grade based on morphology as defined by Schizas and colleague in total, 189 patients were eligible to enter the study. Results: Mean age of patients was $61.5{\pm}9.6years$. Mean follow-up was $36{\pm}12months$. Most patients (88.4%) were classified with grades C (severe stenosis) and D (extreme stenosis). Post-surgical success was 85.7% at the 2-year follow-up. A weak correlation was observed between morphologic grade of stenosis and BMI. Rates of postoperative complications were similar between patients who were obese and those who were non-obese. Both cohorts had similar degree of improvement in the ODI at the 2-year followup. However, patients who were non-obese presented significantly higher surgical success than those who were obese. In ROC curve analysis, a cut-off value of ${\leq}29.1kg/m^2$ for BMI in patients with LSCS was suggestive of surgical success, with 81.1% sensitivity and 82.2% specificity (area under the curve, 0.857; 95% confidence interval, 0.788-0.927). Conclusion: This study showed that the BMI can be considered a parameter for predicting surgical success in patients with LSCS and can be useful in clinical practice.

Development of Preliminary Seismic Performance Evaluation Method for Residential Piloti Buildings Using Stiffness-Based Soft Story Ratios (강성기반 연층비를 활용한 주거형 필로티 건축물의 내진성능예비평가 기법 개발)

  • Choi, Jae-Hyuk;Choi, Insub;Kim, JunHee;Sohn, JungHoon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.34 no.4
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    • pp.175-182
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    • 2021
  • There have been many instances of damage to buildings with soft stories, and it is important to consider vertically irregular buildings when evaluating the seismic performance of existing buildings. However, because conventional methods do not easily reflect vertical irregularities with sufficient accuracy, it is possible to underestimate or overestimate the seismic performance of buildings with vertical irregularities. This study aims to develop a seismic performance evaluation method for vertically irregular buildings using the stiffness-based soft story ratio (SSR), which is a parameter that represents the ratio of the demand and the capacity for displacement and refers to the ratio of displacement concentration in buildings. The seismic performance evaluation method developed in this study is compared with the conventional seismic performance evaluation method for four piloti buildings, using the first-floor column as a variable. Conventional seismic performance evaluation methods often overestimate the seismic performance for models in which vertical irregularities are maximized. However, results of the proposed seismic performance evaluation method are identical to those from a detailed evaluation for all models. Therefore, it is considered that the proposed seismic performance evaluation method can provide more precise seismic performance evaluation results than conventional methods in the case of piloti buildings, where vertical irregularities are maximized.

The Effect of Ground Heterogeneity on the GPR Signal: Numerical Analysis (지반의 불균질성이 GPR탐사 신호에 미치는 영향에 대한 수치해석적 분석)

  • Lee, Sangyun;Song, Ki-il;Ryu, Heehwan;Kang, Kyungnam
    • Journal of the Korean GEO-environmental Society
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    • v.23 no.8
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    • pp.29-36
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    • 2022
  • The importance of subsurface information is becoming crucial in urban area due to increase of underground construction. The position of underground facilities should be identified precisely before excavation work. Geophyiscal exporation method such as ground penetration radar (GPR) can be useful to investigate the subsurface facilities. GPR transmits electromagnetic waves to the ground and analyzes the reflected signals to determine the location and depth of subsurface facilities. Unfortunately, the readability of GPR signal is not favorable. To overcome this deficiency and automate the GPR signal processing, deep learning technique has been introduced recently. The accuracy of deep learning model can be improved with abundant training data. The ground is inherently heteorogeneous and the spacially variable ground properties can affact on the GPR signal. However, the effect of ground heterogeneity on the GPR signal has yet to be fully investigated. In this study, ground heterogeneity is simulated based on the fractal theory and GPR simulation is carried out by using gprMax. It is found that as the fractal dimension increases exceed 2.0, the error of fitting parameter reduces significantly. And the range of water content should be less than 0.14 to secure the validity of analysis.

Effect of the Distributive Justice on Turnover Intention of Workers in Community Rehabilitation Centers : Focusing on the Mediating Effect of Job Satisfaction (장애인복지관 종사자의 분배공정성이 이직의도에 미치는 영향 : 직무만족의 매개효과를 중심으로)

  • Lee, Byoung-Rock
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.2
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    • pp.203-212
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    • 2021
  • The research purpose is analyzing the relationship between the distributive justice and turnover intention of the workers in community rehabilitation centers. This study also examines the mediating effect of job satisfaction between the distributive justice and the turnover intention. For this purpose, the survey was conducted to workers of 14 community rehabilitation centers in Daejeon and Chungnam area, and the 365 data were used for analysis. The results of analysing as follows: 1) the distributive justice of the workers in community rehabilitation centers effected the turnover intention negatively and the job satisfaction positively. In addition, the partial mediating effect of job satisfaction was proved between the distributive justice and the turnover intention. The analysis results show that the distributive justice is the important independent variable of the turnover intention and the job satisfaction is the important parameter between the two variables. According to these analysis results, several suggestions were made to reduce the turnover intention of the workers being engaged in community rehabilitation centers in terms of the improving their distributive justice and job satisfaction.

A System Dynamic for Investigating to Use of Building Information Modeling (BIM) for Hanok Construction (시스템 다이내믹스 기반 한옥건축의 BIM 접목 활성화 방안 연구)

  • Seo, Seung-Ha;Bang, Yei-Dam;Hyen, Ju-Hwan;Yu, Chaeyeon;Lee, Donghoon;Kim, Sungjin
    • Korean Journal of Construction Engineering and Management
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    • v.24 no.5
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    • pp.3-11
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    • 2023
  • Building information modeling (BIM) can help to visualize and manage the building-related information at the object-based level, and it is possible to help link the tasks in the network of Hanok construction. While many studies have significant interest in using BIM for modern construction, there is only few studies to observe the use of BIM for traditional construction, commonly called Hanok construction in South Korea. Hence, the main goal of this study is to develop a system dynamic model for investigating how the BIM can be widely used for Hanok construction. To this end, this study identified the factors influencing the BIM uses for the Hanok construction, developed a causal loop diagram (CLD) to investigate the interrelationships among the factors, and provided a final model based on the mathematical definitions. Based on the scenario analysis, it is demonstrated that the support to building Hanok and education cost for BIM positively influence activating and using the BIM for the Hanok construction. Based on the dynamics of the factors identified in this study, it is important to consider expanding support for Hanok construction and education cost for BIM to successfully integrate and utilize BIM in the construction industry.

The Effect of Characteristics of Venture Business Founders and Management Strategy on Business Performance (벤처기업 창업가의 특성과 경영전략이 경영성과에 미치는 영향)

  • Han, Kyudong
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.6
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    • pp.29-43
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    • 2019
  • This paper empirically analyzed the relationship between the characteristics of venture business founders and management performance, setting the management strategy as a parameter to provide a suggestion for the survival and development of venture companies that play an important role in the national economy and job creation. Previous studies in Korea have analyzed the relationship between the characteristics of business founders, management strategies and management performance in a single dimension. This paper, however, explained the business performance of a company from a multi-dimensional perspective while setting the characteristics of business founders as independent variables and setting the business strategy of the enterprise as a parameter. The first result of the analysis shows that the characteristics of venture business founders have a positive effect on business performance. In particular, among the characteristics of venture business founders, a progressive spirit has had the greatest impact on business performance. On the other hand, the influence of risk sensitivity was very weak. Second, the characteristics of venture business founders were found to have a positive effect on business strategy. In particular, innovation was an important variable that affected the technological innovation differentiation strategy, and a progressive spirit was the most influential factor in the marketing differentiation strategy. Third, management strategies of venture firms were found to have a positive effect on business performance. In particular, the technology innovation differentiation strategy has a greater impact on business performance than the marketing differentiation strategy. Fourth, it was revealed that management strategy partially has a mediated effect on the relationship between the characteristics of venture business founders and management performance. In other words, it was found that the characteristics of the founders have a direct impact on business performance but if it is linked to management strategy it has an indirect effect on business performance. The results of this study show that business performance improves when venture business founders' personal characteristics and the firms' management strategy are combined.

Effect of Peking-Duck By-Product Extracts Supplemented with Medicinal Herbs on Serum Heavy Metal Levels and Blood Parameters of Rats Exposed to Lead and Mercury (한약재를 첨가한 오리부산물 추출액이 납과 수은에 노출된 흰쥐 혈청의 중금속 및 혈액지표에 미치는 영향)

  • Park, Sung-Hye;Shin, Eon-Hwan;Park, Sung-Jin;Ran, Jong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.4
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    • pp.476-483
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    • 2005
  • This experiment was planned to develop a functional supplement by food resources to prevent and lessen the deleterious effects caused by environmental pollutants such as polluted food, air, water and heavy metals. The goal of this study was to investigate the effects of peking-duck extracts supplemented with six kinds of medicinal herbs (DJ) on the intoxication of lead and mercury in rats. Sprague-Dawley rat weighing $150g\pm15g$ g, were randomly assigned to 5 groups, basal diet only (NCG), heavy metal without DJ injection (HCG), heavy metals and DJ (3 mg/mL) injection (HMLD), heavy metal and DJ (30 mg/mL) injection (HMMD), heavy metal and D] (300 mg/mL) injection (HMHD). Mecury (Hg) and lead (Pb) injected at the level of 50 ppm for 17 days. Also DJ oral feeding was continued for 31 days. The result of this study were as follows; Food intake and body weight gain in heavy metal administered groups were lower than those of control group (NCG). The activities of GOT, GPT and BUN level were significantly reduced in DJ-treated groups as compared to HCG. DJ was shown to suppress the accumulation of Hg and Pb in serum. The results suggest that DJ might have protective effect on Hg and Pb intoxication.