• Title/Summary/Keyword: indicator variables

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Density Measurement for Continuous Flow Segment Using Two Point Detectors (두 개의 지점 검지기를 이용한 연속류 구간의 밀도측정 방안)

  • Kim, Min-Sung;Eom, Ki-Jong;Lee, Chung-Won
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.1
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    • pp.37-44
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    • 2009
  • Density is the most important congestion indicator among the three fundamental flow variables, flow, speed and density. Measuring density in the field has two different ways, direct and indirect. Taking photos with wide views is one of direct ways, which is not widely used because of its cost and lacking of proper positions. Another direct density measuring method using two spot detectors has been introduced with the concept of instantaneous density, average density and measurement interval. The relationship between accuracy and measurement interval has been investigated using the simulation data produced by Paramics API function. Finally, density measurement algorithm has been suggested including exponential smoothing for device development.

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Short-term Forecasting of Power Demand based on AREA (AREA 활용 전력수요 단기 예측)

  • Kwon, S.H.;Oh, H.S.
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.39 no.1
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    • pp.25-30
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    • 2016
  • It is critical to forecast the maximum daily and monthly demand for power with as little error as possible for our industry and national economy. In general, long-term forecasting of power demand has been studied from both the consumer's perspective and an econometrics model in the form of a generalized linear model with predictors. Time series techniques are used for short-term forecasting with no predictors as predictors must be predicted prior to forecasting response variables and containing estimation errors during this process is inevitable. In previous researches, seasonal exponential smoothing method, SARMA (Seasonal Auto Regressive Moving Average) with consideration to weekly pattern Neuron-Fuzzy model, SVR (Support Vector Regression) model with predictors explored through machine learning, and K-means clustering technique in the various approaches have been applied to short-term power supply forecasting. In this paper, SARMA and intervention model are fitted to forecast the maximum power load daily, weekly, and monthly by using the empirical data from 2011 through 2013. $ARMA(2,\;1,\;2)(1,\;1,\;1)_7$ and $ARMA(0,\;1,\;1)(1,\;1,\;0)_{12}$ are fitted respectively to the daily and monthly power demand, but the weekly power demand is not fitted by AREA because of unit root series. In our fitted intervention model, the factors of long holidays, summer and winter are significant in the form of indicator function. The SARMA with MAPE (Mean Absolute Percentage Error) of 2.45% and intervention model with MAPE of 2.44% are more efficient than the present seasonal exponential smoothing with MAPE of about 4%. Although the dynamic repression model with the predictors of humidity, temperature, and seasonal dummies was applied to foretaste the daily power demand, it lead to a high MAPE of 3.5% even though it has estimation error of predictors.

Distribution of Epilithic Diatom Communities in Relation to Land-Use and Water Quality in the Geum River System, South Korea (금강수계의 토지이용 및 수질구배에 따른 돌부착 돌말류의 분포특성)

  • Cho, In-Hwan;Hwang, Soon-Jin;Kim, Baik-Ho;Kim, Yong-Jae
    • Journal of Korean Society on Water Environment
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    • v.30 no.3
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    • pp.283-291
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    • 2014
  • To study the distribution characteristics of diatom communities in relation to the gradient of water quality and land-use, water samples and epilithic diatoms were collected from 90 sites including mainstream and tributaries, in the Geum River System (GRS) during no rainfall, May 2011. Of 239 taxa identified, Achnanthes convergens and Cymbella minuta were dominated over all the sites. Cluster analysis on the GRS divided into three groups. Group 1 (G1) is the mountainous upstream, a relatively good water quality, and mainly consisted of saproxenous species. Group 2 (G2) is the urban sites, polluted (high in electric conductivity, total phosphate and soluble reactive phosphorus), and saproxenous and common species. Group 3 (G3) is the agriculture sites, and polluted (turbidity, total nitrogen, nitrate), and saprophilous species. There were some discrepancies between abiotic and biotic variables in GRS; biologically similar between G1 and G2, but abiotically similar between G2 and G3. These differences may attribute to not only physiological characteristics of diatom cells, but complicate relationships between microhabitat and water quality. Thus, an urgent development of generalized or standardized methods to diminish the differences between epilithic diatom community and environments is advent.

Analysis of Nonpoint Sources Runoff Characteristic for the Vineyard Areas (포도밭에 대한 비점오염원 유출특성 해석)

  • Yoon, Young-Sam;Lee, Sang-Hyeup;Yu, Jay-Jung;Lee, Jae-Kwan
    • Journal of Environmental Science International
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    • v.20 no.3
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    • pp.361-372
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    • 2011
  • This study analyzed the characteristics of stormwater runoff by rainfall type in orchard areas for two years. Effluents were monitored to calculate the EMCs and runoff loads of each pollutant. The runoff characteristics for nonpoint sources from vineyards were also inspected based on independent variables that affect runoff such as rainfall and rainfall intensity. The average runoff loads of each pollutant from vineyard_A and vineyard_B were found as follows: BOD 39.13 mg/$m^2$, COD 112.13 mg/$m^2$, TOC 54.98 mg/$m^2$, SS 1,681.8 mg/$m^2$, TN 18.29 mg/$m^2$, and TP 4.06 mg/$m^2$, which indicates that the COD's runoff load was especially high. The average EMCs from vineyard_A and vineyard_B, which represents the quality of rainfall effluent, were also analyzed: BOD 3.5 mg/L, COD 11.5 mg/L, TOC 5.2 mg/L, SS 211.7 mg/L, TN 1.774 mg/L, and TP 0.324 mg/L. This suggested that the COD, as an indicator of organic pollutants, is high in terms of EMCs as well. As rainfall increased, the EMCs of BOD, COD, TOC and SS kept turning upward. At a point, however, the high rainfall brought about dilution effects and began to push down the EMCs. Higher rainfall intensities led to the increase in the EMCs that displays the convergence of rainfall. Low rainfall intensities also raised pollutant concentrations, although the concentrations themselves were slightly different among pollutants.

Evaluation of selection program by assessing the genetic diversity and inbreeding effects on Nellore sheep growth through pedigree analysis

  • Illa, Satish Kumar;Gollamoori, Gangaraju;Nath, Sapna
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.9
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    • pp.1369-1377
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    • 2020
  • Objective: The main objectives of the present study were to assess the genetic diversity, population structure and to appraise the efficiency of ongoing selective breeding program in the closed nucleus herd of Nellore sheep through pedigree analysis. Methods: Information utilized in the study was collected from the pedigree records of Livestock Research Station, Palamaner during the period from 1989 to 2016. Genealogical parameters like generation interval, pedigree completeness, inbreeding level, average relatedness among the animals and genetic conservation index were estimated based on gene origin probabilities. Lambs born during 2012 and 2016 were considered as reference population. Two animal models either with the use of Fi or ΔFi as linear co-variables were evaluated to know the effects of inbreeding on the growth traits of Nellore sheep. Results: Average generation interval and realized effective population size for the reference cohort were estimated as 3.38±0.10 and 91.56±1.58, respectively and the average inbreeding coefficient for reference population was 3.32%. Similarly, the effective number of founders, ancestors and founder genome equivalent of the reference population were observed as 47, 37, and 22.48, respectively. Fifty per cent of the genetic variability was explained by 14 influential ancestors in the reference cohort. The ratio fe/fa obtained in the study was 1.21, which is an indicator of bottlenecks in the population. The number of equivalent generations obtained in the study was 4.23 and this estimate suggested the fair depth of the pedigree. Conclusion: Study suggested that the population had decent levels of genetic diversity and a non-significant influence of inbreeding coefficient on growth traits of Nellore lambs. However, small portion of genetic diversity was lost due to a disproportionate contribution of founders and bottlenecks. Hence, breeding strategies which improve the genetic gain, widens the selection process and with optimum levels of inbreeding are recommended for the herd.

Angiogenesis and Lymphangiogenesis in Oral Squamous Cell Carcinoma: Comparison of Japanese and Indian Cases

  • Chowdhury, Chitta Ranjan;Kirita, Tadaaki;Jose, Maji;Abdullah, Riaz
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.7
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    • pp.3219-3222
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    • 2012
  • A comparative study between 17 Japanese and 19 Indian patients with oral squamous cell carcinomas (OSCCs) revealed that the tumour prognostic indicator mean vessel density (MVD) count for angiogenesis was relatively high at 57.1 in Indian as compared to 39.3 in Japanese (P=0.001) cases, whereas the lymph-vessel density (LVD) count for lymphangiogenesis was lower (12.8 vs 48.0, P=0.002). Both male and female Indians had higher MVD counts, but LVD counts were only slightly lower in females. MVD count was relatively high among the cases below 65 years old in both the countries (P=0.4). Japanese cases with Tongue cancer had higher MVD count, but the Indian cases had lower LVD counts. Size-wise, T2 and T3 had higher counts of MVD both in Indian and Japanese cases. MVD and LVD count was higher in grades II and III both in Japanese and Indian cases. There was insignificant difference of the MVD counts among smokers, but the tobacco chewers in Indian cases had higher counts of MVD and LVD (P value by Bartlett test 0.35, 0.57 respectively). The hot-spots of tumour sites had variable rates of lymphocyte infiltration showed higher MVD counts in all the cases. Although the clinical characteristics and demographic variables usually relate to MVD and LVD counts, the tendency of higher values, especially among tobacco chewers, identified as the highest risk group for occurrence of oral cancer needs to be investigated further.

Prognostic Role of Nucleophosmin in Colorectal Carcinomas

  • Yang, Yu-Feng;Zhang, Xi-Ying;Yang, Mei;He, Ze-Hua;Peng, Ning-Fu;Xie, Shu-Rui;Xie, Yan-Fang
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.5
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    • pp.2021-2026
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    • 2014
  • Aim: Recent research suggests that nucleophosmin (NPM) may be a prognostic marker in colorectal carcinomas (CRC). We here tested its use to predict the survival of CRC patients. Methods: We investigated NPM expression by immunohistochemistry in histologically normal to malignant colorectal tissues and evaluated its association with clinicopathological variables. Overall and disease-free survival after tumor removal were calculated by the Kaplan-Meier method, and differences in survival curves were analyzed by the log-rank test. The Cox proportional hazards model was used for multivariate analysis of prognostic factors. Results: NPM expression was found significantly upregulated in CRC compared to adjacent colorectal tissue, villous adenoma, tubular adenoma and normal colorectal mucosa (p<0.05 for all). NPM expression was statistically linked to cancer embolus, lymph node metastasis, differentiation grade, and recurrence of CRC. Overall and disease-free survival of NPM-negative CRC patients tended to be better than those for patients with NPM-positive lesions (log-rank statistic, p<0.05 for all). Multivariate analysis indicated NPM expression as an independent prognostic indicator for CRC patients (p<0.05 ). Conclusion: Our results suggest that NPM expression can predict the survival of CRC patients. Prognosis of CRC is determined by not only many known prognostic factors but also by NPM expression.

High Cytoplasmic Expression of the Orphan Nuclear Receptor NR4A2 Predicts Poor Survival in Nasopharyngeal Carcinoma

  • Wang, Jian;Yang, Jing;Li, Bin-Bin;He, Zhi-Wei
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.2805-2809
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    • 2013
  • Objective: This study aimed at investigating whether the orphan nuclear receptor NR4A2 is significantly associated with clinicopathologic features and overall survival of patients with nasopharyngeal carcinoma (NPC). Methods: Immunohistochemistry was performed to determine NR4A2 protein expression in 84 NPC tissues and 20 non-cancerous nasopharyngeal (NP) tissues. The prognostic significance of NR4A2 protein expression was evaluated using Cox proportional hazards regression models and Kaplan-Meier survival analysis. Results: We did not find a significant association between total NR4A2 expression and clinicopathological variables in 84 patients with NPC. However, we observed that high cytoplasmic expression of NR4A2 was significantly associated with tumor size (T classification) (P = 0.006), lymph node metastasis (N classification) (P = 0.002) and clinical stage (P = 0.017). Patients with higher cytoplasmic NR4A2 expression had a significantly lower survival rate than those with lower cytoplasmic NR4A2 expression (P = 0.004). Multivariate Cox regression analysis analysis suggested that the level of cytoplasmic NR4A2 expression was an independent prognostic indicator for overall survival of patients with NPC (P = 0.033). Conclusions: High cytoplasmic expression of NR4A2 is a potential unfavorable prognostic factor for patients with NPC.

Survival Analysis and Prognostic Factors for Colorectal Cancer Patients in Malaysia

  • Hassan, Muhammad Radzi Abu;Suan, Mohd Azri Mohd;Soelar, Shahrul Aiman;Mohammed, Noor Syahireen;Ismail, Ibtisam;Ahmad, Faizah
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.7
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    • pp.3575-3581
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    • 2016
  • Background: Cancer survival analysis is an essential indicator for effective early detection and improvements in cancer treatment. This study was undertaken to document colorectal cancer survival and associated prognostic factors in Malaysians. Materials and Methods: All data were retrieved from the National Cancer Patient Registry-Colorectal Cancer. Only cases with confirmed diagnosis through histology between the year 2008 and 2009 were included. Retrieved data include socio-demographic information, pathological features and treatment received. Survival curves were plotted using the Kaplan-Meier method. Univariate analysis of all variables was then made using the Log-rank test. All significant factors that influenced survival of patients were further analysed in a multivariate analysis using Cox' regression. Results: Total of 1,214 patients were included in the study. The overall 3- and 5-year survival rates were 59.1% and 48.7%, respectively. Patients with localized tumours had better prognosis compared to those with advanced stage cancer. In univariate analysis, staging at diagnosis (p<0.001), primary tumour size (p<0.001), involvement of lymph nodes (p<0.001) and treatment modalities (p=0.001) were found to be predictors of survival. None of the socio-demographic characteristics were found to exert any influence. In Cox regression analysis, staging at diagnosis (p<0.001), primary tumour size (p<0.001), involvement of lymph nodes (p<0.001) and treatment modalities (p<0.001) were determined as independent prognostic factors of survival after adjusted for age, gender and ethnicity. Conclusions: The overall survival rate for colorectal cancer patients in Malaysia is similar to those in other Asian countries, with staging at diagnosis, primary tumor size, involvement of lymph node and treatment modalities having significant effects. More efforts are needed to improve national survival rates in future.

Kidney size estimation in Korean children with Technesium-99m dimercaptosuccinic acid scintigraphy

  • Lee, Min Jung;Son, Mi Kyung;Kwak, Byung Ok;Park, Hye Won;Chung, Sochung;Kim, Kyo Sun
    • Clinical and Experimental Pediatrics
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    • v.57 no.1
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    • pp.41-45
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    • 2014
  • Purpose: Renal size is an important indicator to determine adequate organ growth in children. The aim of this study was to estimate renal size with Technesium-99m dimercaptosuccinic acid (DMSA) scan and propose a simple formula for predicting renal length in normal Korean children. Methods: This study included 346 children (148 boys and 198 girls; age range, 1 month to 17 years) in whom renal length was measured using the DMSA scan. Patients with anatomical renal abnormalities or acute pyelonephritis were excluded. Children were divided into two groups: 214 children (61.8%) were less than a year old (group 1) and 132 (38.2%) were ${\geq}1$ year (group 2). Results: Renal length was larger on the left side than the right side, and there was no significant gender-related difference in renal length. We propose the following formula for renal length based on the analysis of the 346 children in our study: the formula was as follows: $4.682{\times}age(month)^{0.137}$, $R^2=0.780$. In group 1, the formula was renal length $(cm)=0.127{\times}age(month)+5.144$, $R^2=0.354$, and in group 2, the formula was $0.334{\times}age(year)+6.477$, $R^2=0.829$. Conclusion: It is difficult to establish simple formulae in infants ($R^2=0.354$). Therefore, further studies including relevant variables are needed for this age group. We proposed formulae to estimate renal length in Korean children over 1 year of age by using the DMSA scan.