1,315 research outputs found
Kalman Filter Aided Cooperative Optical Beam Tracking
In free-space optical communication between mobile terminals relative motion of the terminals requires an active mechanism to maintain optical alignment between the stations. Cooperative optical beam tracking could be used to address this problem. In this alignment scheme, each station tracks the arrival direction of its impinging beam to employ it as a guide to precisely point its own beam toward the opposite station. Tracking is achieved at each station by a quadrant photodetector which generates simultaneous azimuth and elevation error voltages. In this study a Kalman filtering assisted cooperative optical beam tracking has been proposed and its suitability to cooperative beam tracking is discussed. In this method, Kalman filter is employed to predict the alignment error that is used to produce appropriate control signals for re-alignment. Performance of the proposed method has been demonstrated through simulations
Bal Arılarının Genetik Değişkenliği Üzerine Çalışmalarda Bir Araç Olarak Morfometri
This study was conducted to determine whether the classical morphometric method is a good tool for investigating biodiversity of honey bee or not. The research material was consisted of the worker bee samples collected from 55 apiaries in different locations in Turkey. They were surveyed for only two morphometric characters. Due to common characters exit in all morphometric studies of honey bee, the wing length and the cubital index were chosen. In our study, phylogenetic tree obtained and the results given in graphics showed that morphometric method was a good tool for studying of morphological genetic variability. But it may be better if it should be replaced by modern geometrik morphometric method. A review concerning the concept of classical and modern morphometric methods were also been emphesized.Bu çalışma yalnızca iki morfometrik karekter aracılığıyla Türkiye bal arısı biyoçeşitliliğini belirlemek, elde edilen sonuçları benzer çalışmaların verileriyle karşılaştırmak ve böylece klasik morfometrik methodun bu tür çalışmalardaki etkinliğini irdelemek amacıyla düzenlenmiştir. Çalışma için Türkiye?nin farklı yerlerindeki 55 arılıktan işçi arı örnekleri toplanmıştır. Örnekler şimdiye kadar yapılan çalışmaların çoğunda ele alındığı gibi, kubital index ve ön kanat uzunluğu bakımından incelenmiştir. Elde edilen verilerin istatistiki analiz sonuçları klasik morfometrik methodun çeşitli yerel sonuçları karşılaştırmak konusundaki etkinliği bakımından hala geçerli bir araç olduğunu, fakat modern geometrik morfometrik method ile değiştirilirse çok daha etkin bir araç olabileceğini göstermiştir. Eserde klasik ve modern morfometrik metodlara ilişkin genel bir değerlendirme de yapılmıştır
Decision support modeling for sustainable food logistics management
Summary For the last two decades, food logistics systems have seen the transition from traditional Logistics Management (LM) to Food Logistics Management (FLM), and successively, to Sustainable Food Logistics Management (SFLM). Accordingly, food industry has been subject to the recent challenges of reducing the amount of food waste and raising energy efficiency to reduce greenhouse gas emissions. These additional challenges add to the complexity of logistics operations and require advanced decision support models which can be used by decision makers to develop more sustainable food logistics systems in practice. Hence, the overall objective of this thesis was to obtain insight in how to improve the sustainability performance of food logistics systems by developing decision support models that can address the concerns for transportation energy use and consequently carbon emissions, and/or product waste, while also adhering to competitiveness. In line with this overall objective, we have defined five research objectives. The first research objective (RO), which is to identify key logistical aims, analyse available quantitative models and point out modelling challenges in SFLM, is investigated in Chapter 2. In this chapter, key logistical aims in LM, FLM and SFLM phases are identified, and available quantitative models are analysed to point out modelling challenges in SFLM. A literature review on quantitative studies is conducted and also qualitative studies are consulted to better understand the key logistical aims and to identify the relevant system scope issues. The main findings of the literature review indicate that (i) most studies rely on a completely deterministic environment, (ii) the food waste challenge in logistics has not received sufficient attention, (iii) traveled distance is often used as a single indicator to estimate related transportation cost and emissions, and (iv) most studies propose single objective models for the food logistics problems. This chapter concludes that new and advanced quantitative models are needed that take specific SFLM requirements from practice into consideration to support business decisions and capture food supply chain dynamics. These findings motivated us to work on the following research objectives RO2, RO3, RO4 and RO5. RO2, which is to analyse the relationship between economic (cost) and environmental (transportation carbon emissions) performance in a network problem of a perishable product, is investigated in Chapter 3. This chapter presents a multi-objective linear programming (MOLP) model for a generic beef logistics network problem. The objectives of the model are (i) minimizing total logistics cost and (ii) minimizing total amount of greenhouse gas emissions from transportation operations. The model is solved using the e-constraint method. This study breaks away from the literature on logistics network models by simultaneously considering transportation emissions (affected by road structure, vehicle and fuel types, weight loads of vehicles, traveled distances), return hauls and product perishability in a MOLP model. We present computational results and analyses based on the application of the model to a real-life international beef logistics chain operating in Nova Andradina, Mato Grosso do Sul, Brazil, and exporting beef to the European Union. Trade-off relationships between multiple objectives are observed by the derived Pareto frontier that presents the cost of being sustainable from the point of reducing transportation emissions. The results indicate the importance of distances between actors in terms of environmental impact. Moreover, sensitivity analysis on important practical parameters show that export ports' capacities put pressure on the logistics system; decreasing fuel efficiency due to the bad infrastructure has negative effects on cost and emissions; and green tax incentives result in economic and environmental improvement. RO3, which is to investigate the performance implications of accommodating explicit transportation energy use and traffic congestion concerns in a two-echelon capacitated vehicle routing problem (2E-CVRP), is investigated in Chapter 4. The multi-echelon distribution strategy in which freight is delivered to customers via intermediate depots rather than using direct shipments is an increasingly popular strategy in urban logistics. Its popularity is primarily due to the fact that it alleviates the environmental (e.g., energy usage and congestion) and social (e.g., traffic-related air pollution, accidents and noise) consequences of logistics operations. This chapter presents a comprehensive mixed integer linear programming formulation for a time-dependent 2E-CVRP that accounts for vehicle type, traveled distance, vehicle speed, load, multiple time zones and emissions. A case study in a supermarket chain operating in the Netherlands shows the applicability of the model to a real-life problem. Several versions of the model, each differing with respect to the objective function, are tested to produce a number of selected Key Performance Indicators (KPIs) relevant to distance, time, fuel consumption and cost. This chapter offers insight in the economies of environmentally-friendly vehicle routing in two-echelon distribution systems. The results suggest that an environmentally-friendly solution is obtained from the use of a two-echelon distribution system, whereas a single-echelon distribution system provides the least-cost solution. RO4, which is to investigate the performance implications of accommodating explicit transportation energy use, product waste and demand uncertainty concerns in an inventory routing problem (IRP), is investigated in Chapter 5. Traditional assumptions of constant distribution costs between nodes, unlimited product shelf life and deterministic demand used in the IRP literature restrict the usefulness of the proposed models in current food logistics systems. From this point of view, our interest in this chapter is to enhance the traditional models for the IRP to make them more useful for decision makers in food logistics management. Therefore, we present a multi-period IRP model that includes truck load dependent (and thus route dependent) distribution costs for a comprehensive evaluation of CO2 emission and fuel consumption, perishability, and a service level constraint for meeting uncertain demand. A case study on the fresh tomato distribution operations of a supermarket chain shows the applicability of the model to a real-life problem. Several variations of the model, each differing with respect to the considered aspects, are employed to present the benefits of including perishability and explicit fuel consumption concerns in the model. The results suggest that the proposed integrated model can achieve significant savings in total cost while satisfying the service level requirements, and thus offers better support to decision makers. RO5, which is to analyse the benefits of horizontal collaboration in a green IRP for perishable products with demand uncertainty, is investigated in Chapter 6. This chapter presents a decision support model, which includes a comprehensive evaluation of CO2 emission and fuel consumption, perishability, and a service level constraint for meeting uncertain demand, for the IRP with multiple suppliers and customers. The model allows to analyse the benefits of horizontal collaboration in the IRP with respect to several KPIs, i.e., total emissions, total driving time, total routing cost comprised of fuel and wage cost, total inventory cost, total waste cost, and total cost. A case study on the distribution operations of two suppliers, where the first supplier produces figs and the second supplier produces cherries, shows the applicability of the model to a real-life problem. The results show that horizontal collaboration among the suppliers contributes to the decrease of aggregated total cost and emissions in the logistics system, whereas the obtained gains are sensitive to the changes in parameters such as supplier size or maximum product shelf life. According to the experiments, the aggregated total cost benefit from cooperation varies in a range of about 4-24% and the aggregated total emission benefit varies in a range of about 8-33%. Integrated findings from Chapters 2, 3, 4, 5 and 6 contribute to the SFLM literature by (i) reflecting the state of the art on the topic of quantitative logistic models which have sustainability considerations, (ii) providing decision support models which can be used by decision makers to improve the performance of the sustainable food logistics systems in terms of logistics cost, transportation energy use and carbon emissions, and/or product waste, and (iii) presenting the applicability of the proposed models in different case studies based on mainly real data, multiple scenarios, and analysis. The developed decision support models exploit several logistics improvement opportunities regarding transportation energy use and emissions, and/or product waste to better aid SFLM, as distinct from their counterparts in literature. To conclude, the case study implementations in this thesis demonstrate that (i) perishability and explicit consideration of fuel consumption are important aspects in logistics problems, and (ii) the provided decision support models can be used in practice by decision makers to further improve sustainability performance of the food logistics systems. </p
Genetic variation and relationships among Turkish water buffalo populations
The genetic variation and relationships among six Turkish water buffalo populations,typical of different regions was assessed using a set of twenty-six heterologous (bovine) microsatellite markers. Between 7 and 17 different alleles were identified per microsatellite in a total of 254 alleles. The average number of alleles across all loci in all the analyzed populations was found to be
12.57. The expected mean heterozygosity (HE) per population was between 0.5 and 0.58. Significant departures from Hardy-Weinberg equilibrium were observed for 44 locus-population combinations.
Population differentiation was analyzed by estimation of the FST index (values ranging from 0.053 to 0.123) among populations. In the PCA analysis the Merzifon population showed the highest differentiation compared to the others. Also some individuals of the Danamandira population appeared clearly separated. Instead Afyon, Coskun, Pazar and Thural populations represented one single cluster. The assignment of individuals to their source populations, performed using the Bayesian clustering approach implemented in STRUCTURE 2.2 software, has evidenced a high
differentiation of Merzifon and Danamandira populations as well. The results of this study could be useful for the development of conservation strategies of the Turkish buffalo
A Review on Quantitative Models for Sustainable Food Logistics Management
The last two decades food logistics systems have seen the transition from a focus on traditional supply chain management to food supply chain management, and successively, to sustainable food supply chain management. The main aim of this study is to identify key logistical aims in these three phases and analyse currently available quantitative models to point out modelling challenges in sustainable food logistics management (SFLM). A literature review on quantitative studies is conducted and also qualitative studies are consulted to understand the key logistical aims more clearly and to identify relevant system scope issues. Results show that research on SFLM has been progressively developing according to the needs of the food industry. However, the intrinsic characteristics of food products and processes have not yet been handled properly in the identified studies. The majority of the works reviewed have not contemplated on sustainability problems, apart from a few recent studies. Therefore, the study concludes that new and advanced quantitative models are needed that take specific SFLM requirements from practice into consideration to support business decisions and capture food supply chain dynamics
Adolescents' life plans in the city of Madrid. Are immigrant origins of any importance?
Identities formed during adolescence are known to be crucial in shaping future life decisions in multiple domains, including not only the educational and work careers but also partnership arrangements, fertility trajectories, residential choices, even civic and political attitudes. In this article we examine in a very simple and mostly descriptive way the main differences and similarities between the daily life of adolescents of immigrant and non-immigrant origin, and their wishes and expectations for their future, utilizing data from the Chances Survey, collected in 30 secondary schools in the city of Madrid in 2011. Our methods combine a comparison of means, the ANOVA test, multivariate regressions and factor analysis, in order to identify when adolescents of immigrant origin reveal wishes and expectations significantly different from those of their classmates of native origin; and the extent to which they expect higher frustration of their wishes in their future life, or not. Differences by gender are also explored. Our findings suggest similarities and differences between both groups depending on the particular aspect examined, and discard a systematic pattern of greater optimism or pessimism among immigrant adolescents compared to their non-immigrant classmates. Differences by origin tend to be larger when respondents are asked about the immediate future instead of the more distant one, and immigrant girls seem to be the most pessimistic about their future.
Genetic variation and relationships among Turkish water buffalo populations
P>The genetic variation and relationships among six Turkish water buffalo populations, typical of different regions, were assessed using a set of 26 heterologous (bovine) microsatellite markers. Between seven and 17 different alleles were identified per microsatellite in a total of 254 alleles. The average number of alleles across all loci in all the analysed populations was found to be 12.57. The expected mean heterozygosity (H-e) per population ranged between 0.5 and 0.58. Significant departures from Hardy-Weinberg equilibrium were observed for 44 locus-population combinations. Population differentiation was analysed by estimation of the F-st index (values ranging from 0.053 to 0.123) among populations. A principal component analysis of variation revealed the Merzifon population to show the highest differentiation compared with the others. In addition, some individuals of the Danamandira population appeared clearly separated, while the Afyon, Coskun, Pazar and Thural populations represented a single cluster. The assignment of individuals to their source populations, performed using the Bayesian clustering approach implemented in the structure 2.2 software, supports a high differentiation of Merzifon and Danamandira populations. The results of this study are useful for the development of conservation strategies for the Turkish buffalo
Türkiye'de yetiştirilen Ankara Keçisi (Capra hircus) ırkında bir sitogenetik çalışma
Ankara Keçi ırkı Türkiye yerli hayvan genetik kaynakları acısından önemli rol oynamasına karşın bu ırkla ilgili kapsamlı bir sitogenetik çalışmaya rastlanmamıştır. Sunulan ön sitogenetik çalışma ırkın temel kromozomal yapısını araştırmak ve populasyon düzeyinde sitogenetik çalışmalara başlangıç yapmayı amaçlamaktadır. Kan kültürleri hem geleneksel metoda göre ve hem de Timidin metoduna göre düzenlenmiştir. Geleneksel ve GTG-RBA-RBG band karyotipleri elde edilerek ırkın kromozomlarının sentromer indeksleri belirlenmiştir. Band modeli karşılaştırmaları Ankara keçi ırkının keçi türü için standardize edilmiş RBA-RBG band modeli ile benzerliğini doğrulamıştır. Bu çalışma sonucunda Ankara keçisi ırkında populasyon düzeyinde sayısal ve yapısal kromozom anomalilerinin taşıyıcılarının tanımlanması, ırkın verim özeliklerinin geliştirilmesinde daha ileri düzeyde sitogenetik çalışmalara ihtiyaç duyulduğu değerlendirilmiştir.The Angora breed of goat plays an important role for the Turkiye's Native Animal genetic resources point of view; nevertheless, so far, no comprehensive cytogenetic investigation has been performed on this important economic breed. The present preliminary cytogenetic study has been conducted upon a sample of Angora goat breed reared in Turkiye in order to ascertain the basic chromosomal status of the breed and to start a cytogenetic screening at a population level. Blood cultures have been noted according to the conventional methods and synchronized with thymidine. Conventional and GTG-RBA-RBG-banded karyotypes have been produced to determine the relative length and centromeric index of the chromosomes of the breed. Banding comparison confirmed similarity of the Angora breed of goat with the established standardized RBA-RBG banding a pattern of the goat species. Further cytogenetic studies should now be addressed at a population level to identify carriers of numerical and/or structural chromosomal abnormalities in the Angora breed population for implementation of its productive and reproductive efficiency
The assessment of the knowledge and awareness about glaucoma in glaucoma patients and general population: a sample from Turkey
Background: The study aimed to evaluate the level of knowledge and awareness of glaucoma and their possible determinants in a group of people diagnosed with glaucoma and in a population based group without glaucoma.Methods: The study included people with an age range of 40 to 80years; 410 patients without glaucoma who admitted to primary health care service and 113 patients who admitted to hospitals with diagnosis of glaucoma. In addition to Glaucoma Knowledge Level Questionnaire (GKLQ), participants were asked about their socio-demographic characteristics, level of awareness and resources of the information about glaucoma. Multivariate logistic regression and multiple linear regression analyses were used to assess the variants which have impact on the level of the awareness about glaucoma and to evaluate the factors effective on the score of GKLQ, respectively.Results: The ratio of awareness about glaucoma was found to be 64.1% in people without glaucoma. The knowledge and awareness about glaucoma were found to be higher in glaucoma patients compared to healthy people but not at a desired level. The education level was the only factor effecting both awareness and knowledge about glaucoma.Conclusions: As awareness about glaucoma can lead to early detection, the assessment of the knowledge and awareness about glaucoma is very important in terms of disease prevention. Health education and preventive health care services should be programmed including for both glaucoma patients and healthy people based on the level of their education
Racism and anti-racism in Europe: a critical analysis of concepts and frameworks
The targets and expressions of racism vary across Europe. This article discusses the relevance of different descriptions and analyses of racism despite the different terms used in different countries such as ‘ethnic minority’, ‘foreigner’ or ‘black’ and different interpretations of which differences matter. It shows the significance of a cross-national European perspective on racism. There are important convergences across European countries in the discourses and practices of racism, particularly the distinction between ‘useful’ and ‘abusive’ migrants. A cross-European perspective can be an important inspiration for anti-racist struggles
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