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Author(s): 

Baghernejhad Elnaz

Issue Info: 
  • Year: 

    2023
  • Volume: 

    11
  • Issue: 

    2
  • Pages: 

    29-60
Measures: 
  • Citations: 

    0
  • Views: 

    211
  • Downloads: 

    29
Abstract: 

ABSTRACT Despite a wide range of components and criteria affecting travel behavior presented through empirical research, the results of these studies are inconclusive, which could be due to the difference between these components and criteria in the study areas. Therefore, this research presented a method to determine which factors in different physical developments affect travel behavior due to the differences in various physical developments. The required information was collected through 271 questionnaires at the level of three neighborhoods of Monirieh, Koye Bimeh, and Koye Golestan in Tehran, Iran, as the old, conventional, and new neighborhoods, respectively. ANOVA test was exerted to analyze the significant difference between different development patterns in three neighborhoods. Dunnett's T3 was applied to determine which neighborhood caused the difference between groups. Also, the factors affecting travel behavior were obtained based on exploratory factor analysis indicators. Finally, by comparing the results of the ANOVA test and regression analysis, it was discovered that factors such as car ownership, dependence and pro-liking for private cars, density and access to educational centers and parks, access to medical and service centers, and variety and density of retail stores had been introduced as the factors affecting travel behavior due to the differences in development patterns. However, proximity to the public transportation station, accessibility preferences in choosing a residence, dependence, and pro-liking for other than a private car, having a license, number of children under five years old, and age have influenced travel behavior regardless of the variation between neighborhoods. Extended Abstract Introduction Finding factors affecting travel behavior has been one of the main concerns of transportation planners. However, in the last two decades, the importance of the influence of the features of the built environment, including land use, along with demographic-economic characteristics, travel behavior, and attitudes of people, has been raised by urban planners. Studies seek to find factors affecting travel behavior, especially land use characteristics. Despite presenting a wide range of components and criteria affecting travel behavior, the results of the studies are inconclusive, which could be due to the difference between these components and criteria in the study areas. Therefore, this research presented a method to determine which factors in different physical developments affect travel behavior due to the differences in various physical developments. In order to do this, it must first be determined whether the study areas/different development patterns have a significant difference in terms of travel behavior or not. In case of a positive answer to the previous question, the following question is which study areas caused this difference. The next question arises: -Which physical and non-physical characteristics affect travel behavior due to distinctions between different development patterns?   Methodology The present research method is analytical and experimental based on quantitative methods. This research chose the frequency of travel by private car, public transportation, and walking as the travel behavior. According to the research's purpose, indicators and criteria affecting travel behavior were extracted after reviewing the theoretical and experimental literature. Then, the required information was collected through 271 questionnaires at the level of three neighborhoods of Monirieh, Koye Bimeh, and Koye Golestan as the old, conventional, and new neighborhoods, respectively. The questionnaire was compiled as a Likert scale in five parts of travel information, demographic-economic characteristics, perceptual characteristics of land use, travel habits, and access preferences of people in choosing their residence. ANOVA test was used to analyze the significant difference between different groups of a characteristic (here, different development patterns or the three case studies). Dunnett T3 was exerted to determine which neighborhood caused the difference between groups. Also, the factors affecting travel behavior were obtained based on exploratory factor analysis indicators. Finally, by comparing the results of the ANOVA test and regression analysis, it was discovered which factors affecting travel behavior were due to the differences in study areas and which factors affect travel behavior regardless of development patterns.   Results and discussion This research aims to identify the factors affecting travel behavior due to the differences in development patterns. In this regard, the findings in line with the first research question show that the frequency of three modes of travel, by private car, transportation, and pedestrian, differ significantly in the three neighborhoods. Furthermore, ANOVA test results depict that there is a significant difference between these three neighborhoods in terms of factors affecting travel behavior, such as perceptually environmental characteristics of the neighborhood, dependence and pro-liking for personal cars, variety and density of retail stores, density and access to educational units and parks, access to medical and service centers, and car ownership. Finally, by comparing the results of the ANOVA test with the regression analysis assessing the relationship between physical and non-physical factors (the same indicators in the same study areas) with travel behavior, the factors affecting travel behavior owing to different development patterns were identified. Factors such as car ownership, dependence and pro-liking for private cars, density and access to educational units and parks, access to medical and service centers, and variety and density of retail stores have been introduced as the factors affecting travel behavior due to the differences in development patterns. However, proximity to the public transportation station, accessibility preferences in choosing a place of residence, dependence, and pro-liking for other than a private car, having a certificate, number of children under five years old, and age have influenced on travel behavior regardless of the variation between neighborhoods (different physical development patterns).   Conclusion In In order to discover the factors affecting travel behavior due to the differences in patterns of physical development, this research has provided a more detailed analysis of the factors affecting travel behavior. It has achieved more accurate components than previous studies in this regard. Detailed analysis of studies related to travel behavior and finding the main components affecting it, considering the extent of variables and data, can pave the way for professionals in transportation planning and urban planning, in addition to providing detailed methods and criteria in the related literature.   Funding There is no funding support.   Authors’ Contribution Authors contributed equally to the conceptualization and writing of the article. All of the authors approved thecontent of the manuscript and agreed on all aspects of the work declaration of competing interest none.   Conflict of Interest Authors declared no conflict of interest.   Acknowledgments  We are grateful to all the scientific consultants of this paper.

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Issue Info: 
  • Year: 

    2001
  • Volume: 

    8
  • Issue: 

    3
  • Pages: 

    385-405
Measures: 
  • Citations: 

    1
  • Views: 

    184
  • Downloads: 

    0
Keywords: 
Abstract: 

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    2002
  • Volume: 

    55
  • Issue: 

    2
  • Pages: 

    220-231
Measures: 
  • Citations: 

    1
  • Views: 

    147
  • Downloads: 

    0
Keywords: 
Abstract: 

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 147

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Issue Info: 
  • Year: 

    2023
  • Volume: 

    17
  • Issue: 

    1
  • Pages: 

    81-102
Measures: 
  • Citations: 

    0
  • Views: 

    248
  • Downloads: 

    69
Abstract: 

‎The high-dimensional data analysis using classical regression approaches is not applicable, and the consequences may need to be more accurate. This study tried to analyze such data by introducing new and powerful approaches such as support vector regression, functional regression, LASSO and ridge regression. On this subject, by investigating two high-dimensional data sets (riboflavin and simulated data sets) using the suggested approaches, it is progressed to derive the most efficient model based on three criteria (correlation squared, mean squared error and mean absolute error percentage deviation) according to the type of data.

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Issue Info: 
  • Year: 

    2024
  • Volume: 

    3
  • Issue: 

    2
  • Pages: 

    346-360
Measures: 
  • Citations: 

    0
  • Views: 

    0
  • Downloads: 

    0
Abstract: 

Introduction: Powerful and practical statistical packages have simplified the analysis and thus developed the application of data science in all research fields. Accordingly, regression has been applied to almost all aspects of the life sciences. However, misuse of this model has been reported in the past decades. This article aims to examine modeling with this important statistical method and introduce readers to the correct use of this method. Materials and methods: This review article uses real data, and the supplementary materials provide the method for performing the regression analysis in SAS and R statistical software and their related codes. Results: In the required assumptions of the regression model, the residuals of the model must be normally distributed, but performing the normality test for the actual values ​​of the response variable or any of the explanatory variables is not mandatory. Therefore, researchers should not obsess more than necessary about the normal distribution of real data. On the other hand, almost all normality test methods, such as Kolmogorov-Smirnov, are designed for large numbers of data, typically more than a thousand samples. This suggests that using such methods to test the normality of model residuals estimated from a small number of data, mostly less than a hundred cases, would be inaccurate. Another issue regarding applying the regression model is related to the co-linearity of the explanatory variables. There are still signs of correlation in a data set where all variables are generated separately and randomly in a statistical package. This means that it is very hard to find a correlation coefficient equal to zero (r = 0) even between any pair of separate, random variables. Therefore, in all regression models, there are some kinds of correlation between explanatory variables, but the important issue here is that only high correlation causes severe problems in the model. For collinearity test it would be better to use specialized methods such as Variance Inflation Factor (VIF) or Principal Component Analysis (PCA). The linearity of the model is one other assumption of regression model. Data transformation might be helpful under the situation of non-linearity of the model. However, transformation changes the variables unit, altering the array direction in a geometric space. Researchers should be careful regarding the use of modeling a large number of data affects the probability values ​​in variance analysis due to increasing the value of the degree of freedom of the model. Conclusion: As the number of data points increases, the degree of freedom of the error term increases rapidly. Therefore, the final error mean squared significantly reduces. In contrast, the scatter of data points around the regression line may be too wide. For this reason, using the coefficient of determination, usually called (R-Squared), is a suitable criterion for testing the model's fit. High coefficient values indicate a suitable model for the data set used. It should be noted that in a multiple regression model, the higher the number of explanatory variables used in the model, the higher the value of this coefficient increases. For such conditions, when the number of explanatory variables is large, another form of this coefficient, called the adjusted coefficient of determination (adjusted R2), has been introduced. The use of this coefficient in the approximations creates a limit on the number of variables used in the regression model. Accordingly, the number of variables in the model as explanatory variables should not exceed the number of samples (or the number of tens) in a set, and researchers should avoid using more variables than the number of samples.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Author(s): 

Issue Info: 
  • Year: 

    2015
  • Volume: 

    29
  • Issue: 

    -
  • Pages: 

    264-264
Measures: 
  • Citations: 

    1
  • Views: 

    159
  • Downloads: 

    0
Keywords: 
Abstract: 

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Author(s): 

MOHAMMADZADEH M. | HOOMAN A.

Issue Info: 
  • Year: 

    2008
  • Volume: 

    33
  • Issue: 

    4
  • Pages: 

    15-26
Measures: 
  • Citations: 

    0
  • Views: 

    1263
  • Downloads: 

    0
Abstract: 

Discriminant analysis is a way for classification of one object or a group to one or more separate groups that are known or unknown. in scientific researches we often use linear or quadratic functions for classification. But in this paper, we suggest a nonlinear discrimination method that uses two nonparametric.regression methods, namely multivariate adaptive regression splines and adaptive additive model in a simulation study, we investigate the application way of proposed methods and comparing them with the ordinary nonlinear discrimination methods via their means of error rates.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    2013
  • Volume: 

    15
  • Issue: 

    3
  • Pages: 

    27-37
Measures: 
  • Citations: 

    0
  • Views: 

    1170
  • Downloads: 

    0
Abstract: 

Growth analysis is a valuable method in the quantitative analysis of crop growth, development and crop production. In order to evaluate effects of nitrogen rates and plant density on physiological growth indices of safflower, an experiment was conducted at Khorramabad, Lorestan province in 2008. The experiment was carried out as split plot in basis of randomized complete block design with four replications. Three nitrogen application rates were as main plots (N1=control, N2=75 and N3=150 kg/ha net nitrogen) and plant density was as sub plots in 3 levels (D1=40, D2=50 and D3=60 plant/m2). The growth degree day index was used to examine more closely fitting growth curves using non-linear regression models. Appropriate model was selected for each growth index. The results showed that application of nitrogen led to increasing of growth indexes including leaf area, total dry matter and crop growth rate. But, net assimilation rate was reduced. Growth indexes such as, leaf area, total dry matter, did not change with increasing plant density, due to branching of safflower. However, crop growth and net assimilation rate were reduced in plants. Overall, the results show that applied nitrogen has a more positive effect on safflower growth index compared to density changes.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Journal: 

ENGINEERING GEOLOGY

Issue Info: 
  • Year: 

    2023
  • Volume: 

    16
  • Issue: 

    3
  • Pages: 

    131-148
Measures: 
  • Citations: 

    0
  • Views: 

    157
  • Downloads: 

    16
Abstract: 

Evaluating the cutting rate (CR) of stones is important in the cost estimation and the planning of the stone processing plants. This research used regression models to estimate the stones’ CR based on their physico-mechanical characteristics. Stone processing factories in Mahallat City (Markazi province, Iran) were visited, and the CR of diamond circular saws was recorded on six different travertine stones. Next, the stone block samples were collected from the quarries for laboratory tests. Stones’ porosity (n), uniaxial compressive strength (UCS), and Schmidt hammer hardness (SH) were determined in the laboratory as their physico-mechanical characteristics. Correlation relationships of CR with physico-mechanical characteristics were evaluated using simple and multiple regression analyses, and estimator models were developed. Results showed that multiple regression models are more reliable than simple regression for estimating the stones’ CR. The validity of the developed multiple regression models was verified with the published data of one researcher. The findings indicated that these models are accurate enough for estimating the CR of stones. Consequently, the multiple regression models provide practical advantages for estimating the CR and save time and cost during the planning and design of the stone processing factories.

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Issue Info: 
  • Year: 

    1389
  • Volume: 

    1
Measures: 
  • Views: 

    665
  • Downloads: 

    0
Abstract: 

آترواسکلروز و بیماری عروق کرونراز شایعترین علل مرگ و میر در جهان امروز است، و از طرفی اثرات مفید گیاه گلپر در طب سنتی در ارگانهای مختلف بدن مشخص شده است. این مطالعه باهدف بررسی اثر اسانس گیاه گلپر بررگرسیون رگه های چربی fatty streak در عروق کرونر خرگوشهای نر تغذیه شده با کلسترول بالا طراحی شده است. لذا با توجه به اهمیت موضوع این پژوهش با هدف بررسی اثراسانس میوه گیاه گلپر (Heracleum persicum) در regression پلاکهای اترواسکلروزی در عروق خرگوش نر انجام گرفته است. این مطالعه از نوع پژوهشهای تجربی می باشد. در این مطالعه از خرگوش های نیوزلندی سفید با وزن (mean wt=2000gr) استفاده شد بمنظور عادت کردن حیوانات با شرایط به مدت 2 هفته هیچ مداخله ای بر روی آنها صورت نگرفت و در این مدت از غذای معمولی استفاده شد خرگوش ها به مدت 6 هفته رژیم غذایی حاوی 1% کلسترول دریافت کردند در پایان دوره 6 هفته ای 6 خرگوش به طور تصادفی انتخاب و قربانی شدند، 24 خرگوش باقیمانده بصورت تصادفی در 4 گروه 6 تایی تقسیم شدند و به مدت 3 هفته دیگر تغذیه با رژیم پر کلسترول ادامه یافت در این مدت 3 هفته ای مداخلات دارویی انجام شد به طوری که گروه دوم روزانه 2ml/kg حامل، گروه سوم 200 ml/kg اسانس گلپر، گروه چهارم 400 ml/kg اسانس گلپر و گروه پنجم 5 mg/kg لووستاتین به عنوان داروی استاندارد دریافت کردند پس ازتوزین وگرفتن نمونه خون مجدد جهت اندازه گیری لیپیدهای فوق، با آمپول هوا که مستقیما وارد قلب حیوان می شود، قربانی شدند و عروق کرونر حیوانات تشریح وپس از تهیه لام ورنگ آمیزی HSE با میکروسکوپ نوری از نظر وجود یا عدم وجود fatty sreak مورد ارزیابی قرار گرفت. آنالیز داده ها با استفاده از نرم افزار آماری SPSS انجام گرفت. اسانس گلپر با دوز 200 ml/kg غلظت کلسترول تام را به میزان 22.5% و با دوز 400 ml/kg به میزان 40% کاهش داده است (در مقایسه با مقادیر مربوط به شش هفته). لووستاتین به عنوان داروی استاندارد نیز 40% کاهش در غلظت کلسترول ایجاد کرده است. P<0.05 اختلاف معنی دار در مقایسه با گروه کنترل (A) در زمان 9 هفته را نشان می دهد که موید تاثیر اسانس گلپر در رگرسیون پلاک های اترواسکلروتیک می باشد. همچنین درمان با اسانس گلپر در دوز بالا اثری مشابه با لووستاتین دارد درحالیکه عوارض ناشی از آنرا ندارد اسانس گلپر در دوز های 200 ml/kg و 400 ml/kgو لووستاتین به ترتیب به میزان 27.2، 44.8 و 46.5 درصد غلظت LDL را در مقایسه با زمان شش هفته کاهش داده اند که این تغییرات در مورد اسانس با دوز 400 ml/kg و لووستاتین با P<0.05 از نظر آماری معنی دار است. نتایج فوق نشانگر این است که اسانس و عصاره گلپر احتمالا می تواند میزان سطح سرمی کلسترول و LDL را بعنوان لیپوپروتئین های مضر که در فرآیند ایجاد ضایعات آترواسکلروز نقش دارد کاهش داده و میزان سطح سرمی HDL را که به عنوان لیپوپروتئین مفید تلقی می گردد، را افزایش دهد. همان طور که ملاحظه می شود نه رژیم غذایی پر کلسترول و نه نه مداخلات داروئی هیچ کدام تغییر قابل ملاحظه ای در غلظت سرمی تری گلیسرید ایجاد نکرده است. نتایج تشکیل fatty streak در شریان کرونر راست و چپ در نمودارهای شش و هفت مشخص شده است و در این شریان ها نیز اسانس با دوز بالا و لووستاتین نه تنها از پیشرفت تشکیل fatty streak جلوگیری کرده اند بلکه تا حدودی نیز (P<0.05) باعث کاهش یا از بین رفتن fatty streak شده اند. کلیه نتایج بدست آمده از این مطالعه در مجموع نشان می دهد که میزان سطح سرمی ایندکسهای بیوشیمیایی بدست آمده و ارزیابی هیستوپاتولوژیک مقاطع مکمل هم بوده و تایید کننده اثر گلپر بر فرآیند آترواسکلروز و کاهش ضایعات آن می باشد.

Yearly Impact:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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