An Analysis of the Effect of Temperature on Asphalt Paving in South Dakota

Temperature is an important parameter to consider for asphalt paving since this work is generally susceptible to weather due to outdoor construction. The South Dakota Department of Transportation (SDDOT) developed working day weather charts in 1998 to address the expected adverse weather days. This thesis investigated the effect of temperature on adverse weather days for asphalt paving and compared them to the value reported in the 1998 SDDOT study. Moreover, the thesis also examined how closely the maximum temperature data from project sites\u27 weekly progress reports (WPR) matched the data from the closest weather stations. When the maximum temperature (TMAX) of a day is below a certain threshold maximum temperature, that day is counted as a threshold violation (TV) day. The weather data was collected from the National Oceanic and Atmospheric Administration (NOAA) website, and the WPR data of project sites was obtained from SDDOT. Average and 7-year moving average are used to analyze the TV days. The results show that the threshold violation days are generally greater than the State average adverse weather days at 45°F threshold both annually and monthly (January, April, October). However, these violation days are generally less than the State average when the threshold is 40°F. The lift thickness of surface course must be greater than 1 inch, when the temperature during asphalt paving is between 40°F and 45°F in order to get more working days. Most of the project sites (6 out of 9) show a low percentage of maximum temperature data match with the corresponding NOAA stations. It is apparent from the analysis that that there is no direct relationship between the data match percentage, and the distance of project site and NOAA station

Effects of Economic and Population Factors on Health Expenditures: Special Case of Pakistan

This paper aims to explore the factors affecting the health care expenditures of Pakistan by employing the Multivariate techniques for the annual data series from 1960 to 2010 .The variables we considered are Gross Domestic Product (GDP) as an economic indicator, Population of age 65 and above (P≥65), Population of age 0 to 14 (P(0-14)), Life expectancy at Birth (LE), Crude Birth rate (CBR) and population growth rate (GR) as population indicator and Total Health Expenditure (THE) as an influencing factor. Multiple regression considering Total Health Expenditure (THE) is applied as dependent on the variables mentioned above. Since Variance Inflation Factor (VIF) for all independent variables are very high, the smallest VIF is around 11 goes up to 65. The results obtained by Principal components reveal the effect of population structure and the age factor effect oppositely on Total Health Expenditures (THE). Factor Analysis suggests that the behavior of Health Expenditures is common with Gross Domestic Product (GDP), population of age 65 and above (P≥65) and life expectancy at Birth (LE) in Pakistan while population of age 0 to 14 (P (0-14)), population growth rate (GR) and Crude Birth rate (CBR) are moving in opposite direction i.e. as GDP, P≥65 and LE of Pakistan increases P (0-14), GR and CBR will decreases

Spatial Data Analysis for Traffic Safety Network Screening

Problem - The roadway system represents a major investment, both public and private, and a valuable resource that enables mobility and accessibility to users. Due to degradation of aging infrastructure and increasing traffic, transportation agencies are seeking to effectively update or improve the system. With rising costs, tight budgets, and limited land resources, agencies are seeking effective techniques for identifying critical mobility and safety concerns. Historically, assignment of crashes to portions of the network, whether segments or intersections, has been the primary manner to link crash and road elements. Purpose – The primary goal is to explore a potentially more efficient and effective means of developing roadway connected crash cluster identification results as an input to network screening and diagnostics. Beyond this, using the data linkages, we intend to explore crash typology (e.g., severity, collision type) distributions and clusters with respect to network (traffic and roadway) characteristics. Nuance – The research uses GIS and spatiotemporal analysis techniques relying on crash locations as a basis rather than elements of the road network (e.g., intersections, non-intersections). The intent of the analysis is to develop crash clusters that can be flagged for further analysis and potential mitigation. Data – Crash, roadway geometrics, and traffic data of 5 years (2015-2019) were collected for Story County of Iowa. These readily available data are being analyzed using Geospatial Information System (GIS) and some statistical models such as the Markov Switching Models (MSM). Existing methodologies will also be used to develop results that will be compared with the new methodology. Prior Studies – There have been many network screening methods since the 1970s and the more widespread inception of computing resources. Though these methods have some advantages, they do have several shortcomings as well as detailed in the Highway Safety Manual (HSM). Due to these shortcomings, the HSM and other sources promote methods that address these shortcomings such as the Empirical Bayesian (EB) and Hierarchical Bayesian (HB) methods. Historically, assignment of crashes to segments or intersections, has been the primary manner to connect crashes and road elements. The use of GIS and spatial and temporal analysis, alternative methods for connecting crashes to the roadway network have been developed to replace the older methods like screening with additional differentiating criteria. Impact – The primary outcome of this research is the development of a new method of generating distributions and clusters of crashes along a roadway network for use in traffic safety screening. Practitioners should be able to utilize the process to develop network screening related to their jurisdictions, given sufficient and appropriate input data. Keywords –Transportation Engineering, Network screening, Crash rate, Spatial analysis, GIS, Iowa Data, Markov switching models

Perception of distance learning in Bangladeshi tertiary education: prospects and obstacles in the Covid-19 era

Purpose: The key purpose of the study is to understand the university students' perception of a sudden distance learning platform from Bangladesh (a least developed countries' perspective). Research methodology: This particular study has employed a qualitative research method with the support of interview and observation methods. The study has selected 20 University students as a sample size based on purposive sampling. Results: The findings provide a vivid outline of the current situation of the universities- that the students have- over the influence of distance learning on education, technology, their university, course instructors, and themselves. Limitations: The data was qualitative in nature and the study only interviewed the university students but not the other stakeholders of that system; in addition, the study did not triangulate the data with more quantitative data. Contribution: The study makes an important contribution to the literature on the least developed countries' university education, which will benefit Higher Education institutions that are also struggling with the prospects and obstacles of distance learning during and in the post-Covid-19 crisis

Spatial Data Analysis for the Development of Expected Adverse Weather Charts for Transportation Construction Projects

Problem - Seasonal and daily weather events impact construction projects across the various climate regions of South Dakota in differing fashions. Additionally, the impacts for similar weather events can impact grading, surfacing, and structural construction activities in various ways. Adverse weather conditions can cause major delays which may lead to time extensions and increase project cost. Purpose – To address these issues, South Dakota Department of Transportation (SDDOT) developed Working Day Weather Charts in 1998. However, advances in construction practices and weather prediction as well as climatic changes have occurred over the interim 25 years. This study is focused on developing updated zones, tables, charts, and recommendations for roads and bridges construction in South Dakota. Nuance – The tables and charts are planned to be developed on both weekly and monthly basis to determine the impact of adverse weather events on construction projects and for use in future contracts. Data - Weather, soil, and hydrographic data for South Dakota state are being considered for this study. The primary importance is on the weather data which is collected for 30 years (1991-2020) period from National Oceanic and Atmospheric Administration (NOAA). The important weather data parameters are temperature, snow, rainfall, and wind. The soil data have been collected from the broad-based inventory of soils and non-soil areas of the United States namely State Soil Geographic (STATSGO2). The key focus is to analyze the soil parameters in combination with adverse weather events that affect the construction of roads and bridges. The hydrographic data is focused on the peak flow at major water bodies in South Dakota that may cause flooding or ponding which affects road and bridge construction. Additionally, interviews with SDDOT personnel and construction contractors were conducted to determine factors important to the industry. Starting with data exploration of all the available data, key parameters will be analyzed to develop updated expected adverse weather day chart and updated zones. Prior Studies – A considerable amount of work has been done on effects of weather on construction type categories and various Department of Transportation agencies evaluate the use of adverse weather in contract time calculations. The Virginia Department of Transportation place contract determination guidelines online. The VDOT document provides steps in determining contract time but contained little information on the impact of adverse weather on contract time calculations. Another document from the National Research Council of Canada on construction work protocols during winter in 1971. Beyond that, a recent (2022) publication from the National Cooperative Highway Research Program (NCHRP) covers a systematic approach for determining construction contract time. However, in most papers, little information is documented on the impact of adverse weather and how to implement that in tables and charts for construction type activities across South Dakota. Impact – The results can directly help SDDOT engineers and contractors to estimate the appropriate contract time and warranted time extension due to unexpected adverse weather for variety of transportation construction projects across the diverse geographical terrains and climates of South Dakota. Keywords: Transportation, Adverse Weather, Construction, NOA

Cobalt(II) chloride. Aluminium promoted allylation of aldehydes with allylic halides

In the presence of cobalt(II) chloride-metallic aluminium, allylic halides react with aldehydes at room temperature in tetrahydrofuran-water to afford the corresponding alcohols in high yields

Determinants of Users’ Satisfaction Regarding Mobile Operators in Bangladesh: An Exploratory Factor Analysis Approach on University Students

Customer satisfaction is an important issue in current marketing field. This paper basically prepared based on 444 respondents (University Students) to understand which factors make them most satisfied toward their using cell phone operator’s service. Five major cell phone operators (Grameenphone, Banglalink, Robi, Airtel, and Teletalk) have been picked up along with 28 service items (Such as call charge rate, network facility, various offers, balance transfer system etc.) The study is conducted by factor analysis to identify the major factors that influencing users’ satisfaction. The study attained 7 factors as-Various Offers, Charge Rate, Digital Services, Internet Services, Recharge Facilities, Network Coverage and Customer Care Services. The study reveals that users (University Students) have more emphasis on various offers. The findings confirmed that Various Offers, Charge Rate, Digital Services, Internet Services, Recharge Facilities, Network Coverage and customer Care Services contribute strongly to generating customer satisfaction. From the study cell phone operators of Bangladesh can get a specific view about the factors that directly influence customer satisfaction especially the University students’ demands. Keywords: Users’ Satisfaction, Cell Phone Operators, Factor Analysis, Banglades

Impact of the COVID-19 Pandemic on Learning: Assessing Cognitive, Affective, and Psychomotor Skills

The acquisition of cognitive, affective, and psychomotor skills is highly important for successful learning outcomes. This article aims to evaluate the Three-Domain Model (TDM) of learning (cognitive, affective, and psychomotor) during the COVID-19 online classes for tertiary students in Bangladesh. This current study aims at the psychometric evaluation and validation of tertiary students' learning loss during the pandemic. A survey questionnaire is administered using the Likert scale. The components of the questionnaire are based on the Three-Domain Model reflecting the cognitive, affective, and psychomotor skills of the students. The article informs of the learning loss due to the pandemic while suggesting the benefits of online classes. The major finding of the article is that learners lost their skills mainly related to the cognitive domain during the pandemic due to online classes. However, at the same time, their skills related to affective and psychomotor domains increased. Therefore, recommendations for minimizing learning loss are also provided to guide future empirical work in the post-pandemic era