scholarly journals INCREASING THE ECOLOGICAL LEVEL OF PUBLIC TRANSPORT IN THE CITY OF SOFIA

2020 ◽  
Vol 1 ◽  
pp. 57-61
Author(s):  
Iliya Gatovski

The paper explores some of the major factors affecting the environmental friendliness of urban bus transport, with a focus of the modernization of rolling stock and alternative sources of fuel. The surveys are based on an 11-year period, from 2008 to 2019, for which an analysis was made of how much emission reductions in buses with a higher Euro standard are being followed, as in the case of Sofia Motor Transport EAD in Sofia, Bulgaria. As a result, we conclude that transport research and innovation are crucial to ensuring fast, safe and clean transport for citizens and businesses in big cities. The transport sector is more than ever in need of innovative solutions, as the cost of transporting passengers will increase in value and time. This is especially urgent for Bulgaria as the available rolling stock is outdated and in need of renovation.

2011 ◽  
Vol 255-260 ◽  
pp. 279-283
Author(s):  
Jun Qing Guo ◽  
Zhou Can Fu

This paper expatiates the prominent effect of axial compression ratios on the ductility of reinforced concrete frame columns and the limits of the ratios in Code for Seismic Design of Buildings and summarizes the ductility design methods of frame columns with high compression ratios. The principles of value engineering were adopted to analyze the major factors affecting the ductility of reinforced concrete frame columns. The cost of columns with high compression ratios and different types of ties in a real project was calculated and relevant analysis and evaluations were conducted according to Value Coefficient Discriminance. At last the optimum ductility design method for frame columns with high compression ratios was put forth, with which reference can be made in design.


Author(s):  
Mohsen Rasoulian ◽  
Ali Akhavan Ghannadi ◽  
Alireza Nojoomi

Abstract In the contemporary world, the insurance industry is considered one of the crucial factors of the development and progress of countries, and the insurance condition is an indicator of this phenomenon. The aim of the study is to assess risk taking of insurance companies from the perspective of senior managers and experts. The methods of research are questionnaire and interview with experts and senior managers of life insurance of active insurance companies in the city of Tehran using random sampling. In the present study, among 60 senior managers and experts, descriptive statistics in the field of demography such as gender, background, and educational level of respondents have been studied, and then they have been asked for the confirmation and rejection of statistical assumptions in the form of known criteria and opinions of experts and decision-makers. To prioritise the factors from the hierarchical analysis process for factor ranking, the results have indicated that inflation, governmental policies and lack of expertise are the major factors affecting risk taking in the industry of life insurance.


Author(s):  
Mohammed Algahtany

Public construction projects in Saudi Arabia have been suffering from low performance for the past decade. Cost overrun is one of the most important issues in project’s performance and is nearly associated with most of public projects. The aim of this study is to identify and assess the major factors leading to cost overruns in education construction projects in the Northern Province of Saudi Arabia to minimize the risks’ effects in future projects. The research methodology started by identifying cost overrun factors through literature review, project’s documentations, and experts’ interviews. Professionals who worked at the construction projects undertook a questionnaire survey to investigate the importance of the cost overrun factors. The top factors of cost overrun were identified through the analysis of the factors’ occurrence and severity. The study main results included the top causes of cost overrun which are delay in contractors’ progress payment by client, difficulties in financing project by contractor, delays in sub-contractor’s work, additions of quantities such as excavation, backfill, and concrete works, and bid award for lowest price. The investigated risks in the study should be evaluated and mitigated in future projects to minimize their effects and enhance the industry performance.


Resources ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 100
Author(s):  
Dmitrii Zakharov ◽  
Alexey Fadyushin ◽  
Denis Chainikov

The work proposes a methodological approach to studying and assessing the environmental sustainability of the transport system of the city. The authors have selected parameters for assessing the environmental sustainability of the transport system and identified significant factors affecting environmental sustainability. A coefficient of environmental sustainability of the urban transport system and a formula for its calculation are proposed. A simulation was used to assess the amount of emissions of harmful substances from the car exhaust gases if the demand structure changes with respect to the means of transport and transportation methods. The paper presents the results of changing the parameters of the traffic flow and demand by means of transport and transportation methods when introducing a parking fee in the central part of the city, changing the cost of parking and expanding the paid parking area.


2017 ◽  
Vol 66 (2) ◽  
pp. 40-48 ◽  
Author(s):  
S Lunyova Irina ◽  
Oksana Ju Ivanova ◽  
Aleksander V Khardikov ◽  
Tatyana S Ivanova ◽  
Natalya V Abrosimova

Aim. For the past hundred years, changes in the dynamics of fertility has been terrific in Russia, the transition has been from traditional to new, modern type of reproductive behavior. The purpose of the study. To study the demographic indicators of fertility and social factors affecting these figures in the Kursk and Belgorod regions for 25 years (1990-2015). Materials and methods. Based on annual statistical data of RosStat, we researched the dynamics of fertility in the Kursk and Belgorod regions between 1990 and 2015. According to the survey of 1291 women aged 20-34 years living in Kursk, we gave the major factors influencing on the fertility and childlessness. Results. In the Kursk and Belgorod regions from 1990 to 2000 there is a decrease in the birth rate 34.7% and 38%, respectively, with a minimum value in 2000 (р > 0,05). But in the period from 2000 to 2015 there is an increase of this index in Kursk region 50.6%, in Belgorod – by 43.8%, in Russia – 52.9% (р > 0.05), but the birth rate has not reached the 1990 data and remains below the national average. The increase in the birth rate due to increase in births of the second and subsequent children, mostly in rural areas. At the same time, the total fertility rate, which is calculated for the total population, in rural areas recorded significantly lower than in the city. This is due to a lower proportion of residents of reproductive age in the total population of the village compared with the city. Between 1990 and 2015 significantly increases the share of births over the age of 25 and decreases in the age range 18-24 years. Conclusion. It is proved that the birth rate is governed by the number of marriages, with the ratio of male and female population of reproductive age, maternal mortality.


Author(s):  
Salami A. Nasirudeen ◽  
M. A. Aminu ◽  
M. S. Haruna ◽  
E. N. C. Okafor

Electric vehicle is a sustainable development which is capable of transforming the transport sector. It is a sustainable alternative to internal combustion engine-based vehicle. Its technology is based on utilization of sustainable energy resources which are eco-friendly and replenishes in nature. Wide deployment of electric vehicle is expected to minimize the challenge of fossil fuel depletion and greenhouse emissions are expected to be reduced. However, despite all aforementioned advantages of the electric vehicle, its wide deployment faces some challenges including cost, size and range anxiety. Electric vehicles have limited range which is one of the major factors affecting its market penetration.  Researchers highlighted several strategies/methods of extending its driving range. Thus, this work presents a review of different strategies proposed on range extension of the electric vehicle. The strengths and weaknesses of some of the proposed methods are also presented in this work.


2019 ◽  
Vol 11 (4) ◽  
pp. 559-575
Author(s):  
Bencherif Houria ◽  
Boubakour Farès

Purpose The Algerian transport sector has undergone profound changes in recent decades with its privatization. Transport sector liberalization has achieved its primary objectives aimed at increasing public transport supply, but it has been accompanied by travel conditions deterioration because of public regulation insufficiency. For this, the Algerian State has put regulatory and institutional mechanisms to improve urban transport service quality. These mechanisms directly impose on operators and managers of transport means reception stations to meet the expectations of road users. The purpose of this study is to draw a portrait of the service quality of the Algerian urban transport. For this, a fieldwork was carried out in Batna city to know the degree of satisfaction of urban transport users toward the service offered. Design/methodology/approach In this work, the authors used questionnaires as a means of data collection. The study sample is composed of 102 users of the line. The questionnaire deals with personal data (age, sex, level of education, family and professional data), data on the nature of travel between the city of Batna and Tazoult (reasons for travel, travel time and the number of trips undertaken) and measure of user satisfaction on the Tazoult–Batna line according to the criteria of service offer, accessibility, information, duration, attention to the customer, comfort, security and environmental impact. In this work, participatory observation was also used to give a better understanding on how the urban network operates in the city. To this end, an observation grid with key questions has been prepared. It is concentrated on three axes: the actual organization of private operators providing urban bus transport, the state of buses, stations and stopping points and the practice of control by the services concerned. For this, trips were made on all urban lines during the study period. Discussions were conducted with some private operators to find out their positions and their roles in the operation of urban bus transport. Findings The results of this work show that satisfaction levels were average for transport supply, accessibility, duration, attention paid to customer, comfort and safety; however, they were low concerning information and environmental impact. The present work has made it possible to highlight the impacts of urban transport disorganization on the offered service. In addition, taking into account the expectations of users in terms of service quality should have positive impacts for the users themselves, for private and public operators and for urban transport managers. Originality/value This work presents a state of knowledge on the service quality in an urban environment and delivers information on the situation in Algeria without pretending to be exhaustive. However, the contribution of this study is not limited to the evaluation of the various criteria themselves, which are found in whole or in part in many studies devoted to this kind of evaluations. The real contribution of this work lies in highlighting the impacts of urban transport disorganization on the offered services quality. This disorganization is essentially characterized by a weakness or absence of an institutional framework and the multiplication of actors at different levels of intervention, which creates overlapping responsibilities or organizational gaps.


Author(s):  
Sosina Kassa ◽  
Wondiye Admasu ◽  
Shegaw Yesgat

The three-stone fire stove is inefficient in converting solid fuels to energy and, it only yields 5 up to 20 per cent of the overall thermal efficiency. Fuel-efficient stoves are expected to contribute to the environment, economic and health sectors by achieving sustainability in the energy sector. Therefore, due to the benefits of the fuel-efficient stoves, the need to study factors influencing the adoption of these stoves are becoming more important. The study aimed to assess factors influencing the adoption of fuel-efficient stoves in Dessie Zuria Woreda. Both qualitative and quantitative approach was used. Data was collected through questionaries’ in 166 households and interview from 10 key informants. The collected data from questionaries’ was analysed by descriptive statistics, independent sample t-test, one sample t-test and binary logistic regression. One sample t-test result showed that the perception of peoples is significantly different from neutral. The independent sample t-test showed that the average time taken to collect fuelwood is significantly different between adopters and non-adopters.  Educational level, family size, distance from the city, awareness, access to training, the time is taken to collect fuelwood and membership of social organization group were found to be significant in determining the probability of fuel-efficient stove adoption positively at p<0.05 level of significance. The main barrier for not adopting fuel-efficient was found to be a lack of awareness about the benefit of the stove and the cost of the stove.


2020 ◽  
Vol 21 (5) ◽  
pp. 1577
Author(s):  
Samuel Lan ◽  
Chunfang Zheng ◽  
Kyle Hauck ◽  
Madison McCausland ◽  
Scott D. Duguid ◽  
...  

Molecular markers are one of the major factors affecting genomic prediction accuracy and the cost of genomic selection (GS). Previous studies have indicated that the use of quantitative trait loci (QTL) as markers in GS significantly increases prediction accuracy compared with genome-wide random single nucleotide polymorphism (SNP) markers. To optimize the selection of QTL markers in GS, a set of 260 lines from bi-parental populations with 17,277 genome-wide SNPs were used to evaluate the prediction accuracy for seed yield (YLD), days to maturity (DTM), iodine value (IOD), protein (PRO), oil (OIL), linoleic acid (LIO), and linolenic acid (LIN) contents. These seven traits were phenotyped over four years at two locations. Identification of quantitative trait nucleotides (QTNs) for the seven traits was performed using three types of statistical models for genome-wide association study: two SNP-based single-locus (SS), seven SNP-based multi-locus (SM), and one haplotype-block-based multi-locus (BM) models. The identified QTNs were then grouped into QTL based on haplotype blocks. For all seven traits, 133, 355, and 1208 unique QTL were identified by SS, SM, and BM, respectively. A total of 1420 unique QTL were obtained by SS+SM+BM, ranging from 254 (OIL, LIO) to 361 (YLD) for individual traits, whereas a total of 427 unique QTL were achieved by SS+SM, ranging from 56 (YLD) to 128 (LIO). SS models alone did not identify sufficient QTL for GS. The highest prediction accuracies were obtained using single-trait QTL identified by SS+SM+BM for OIL (0.929 ± 0.016), PRO (0.893 ± 0.023), YLD (0.892 ± 0.030), and DTM (0.730 ± 0.062), and by SS+SM for LIN (0.837 ± 0.053), LIO (0.835 ± 0.049), and IOD (0.835 ± 0.041). In terms of the number of QTL markers and prediction accuracy, SS+SM outperformed other models or combinations thereof. The use of all SNPs or QTL of all seven traits significantly reduced the prediction accuracy of traits. The results further validated that QTL outperformed high-density genome-wide random markers, and demonstrated that the combined use of single and multi-locus models can effectively identify a comprehensive set of QTL that improve prediction accuracy, but further studies on detection and removal of redundant or false-positive QTL to maximize prediction accuracy and minimize the number of QTL markers in GS are warranted.


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