536 research outputs found
Reviewing development of active labour market policies and the evaluation techniques
Active labor market policies are commonly used tool to fight unemployment. In the early 1960s all Scandinavian countires have introduced several different measures to have an effect on their labor markets. In the late 1970s in most developed countries of OECD government expenditures on those policies reached the level of 1-1.5% of GDP. High levels of expenditures created a need to assess the impact of such measures and perform their cost-benefit analysis. Evaluations have in the previous 30 years been undertaken by using different methods: from experimental and quasi-experimental, to micro and macro analyses. Most precise evaluations are based on complex econometric methods. Moreover, during last decade there have been several meta-analyses to make cross-analysis of evaluations made worldwide in a long time-span. General conclusions of most papers are that ALMP do not have very high influence on the employability. The best results are experienced in services provided by local national employment services, as well in training programs, especially in on-job training. In the last few years there have appeared some indications that subsidized employment has high positive effects, however there is no general consensus on that matter. Despite large number of published papers on evaluations, there has been no research aimed on analyzing overall ALMP effects on the economy, and creation of a model which could ex-ante estimate future effects of ALMP.Active policies, evaluation, econometric models, economy
Considerations regarding investments efficiency in agriculture
In the present days, we consider that it will be very interesting and useful to do some research on the agricultural sector (distinct from the industrial and other sectors of economic activity), although the process of globalization in modern economies determine trends converged approach and integrated development of rural and urban areas. In this paper we will try do some considerations regarding the problems of agricultural production and some characteristic ways of addressing the economic efficiency of investments held within it.agriculture, efficiency, investments, effectiveness.
Strategy elements of export improvement in agro-economy of Serbia
In forthcoming period, export organizations are going to face tougher competition, which will significantly influence on expectable export effects of their products. This factor must be counted on, and the only way to long-term neutralize the negative effects, based on insufficient competitiveness of domestic goods, is in constant efforts for competitiveness level increment of these products. That is to say, all reserves, primarily in the field of larger productivity and decreasing the production costs have to be engaged in this plan. That implies also certainly slower prices increment, as well as solutions regarding adequate export impulse and relief of export - oriented production, which would certainly help to react more efficient and faster to conditions on foreign market. Regarding comparative advantages, Serbia insufficiently uses even realistic natural possibilities for agricultural products production.agro-economy, strategy, export, cooperation
Two-dimensional lubrication analysis and design optimization of a Scotch Yoke engine linear bearing
Recent study has shown that the application of a Scotch Yoke crank mechanism to a reciprocating internal combustion engine reduces the engine's size and weight and generates sinusoidal piston motion that allows for complete balance of the engine. This paper describes detailed investigation of the performance of a linear bearing assembly, which is one of the key components of the Scotch Yoke mechanism. The investigation starts by solving Reynolds equation for the Scotch Yoke linear bearing. The two-dimensional lubricant flow is numerically simulated and the calculated results are compared with experimental results from a linear bearing test rig. The performance characteristics and a design sensitivity analysis of the bearing are presented. Dynamic testing and analysis of an instrumented linear bearing on a test rig are used to validate the numerical simulation model. The oil supply and lubrication mechanism in the linear bearing are analysed and described in detail. This work aims to provide new insights into Scotch Yoke linear bearing design. In addition, strategies for optimization of the linear bearing are discussed
Ecological, Economic and Marketing Aspects of the Application of Biofertilisers in the Production of Organic Food
Capability framework for sustainable manufacturing of sports apparel and footwear
The sporting goods sector is characterized by large volumes of production, high levels of consumption and short product life cycles resulting in high disposal rates and waste. Manufacturing of sports products is distributed globally through tier-based supply chains and complex logistics systems. Companies within such supply chains have different levels of capability in sustainable manufacturing, which impacts on the sustainability of the overall business. Reducing environmental impacts is of particular concern for companies at present, due to heightened requirements for the reduction of energy and water consumption, waste and greenhouse gas (GHG) emissions. This article describes outcomes of a research project conducted in collaboration with a global sporting goods manufacturer that focused on the development of relevant capabilities across their supply chain for sustainable manufacturing of sports apparel and footwear. The article presents the developed sustainable manufacturing framework and capability assessment results obtained for selected companies within the supply chain of this global manufacturer in Asia
A novel hierarchical clustering algorithm for the analysis of 3D anthropometric data of the human head
In recent years, the use of 3D anthropometry for product design has become more appealing because of advances in mesh parameterisation, multivariate analyses and clustering algorithms. The purpose of this study was to introduce a new method for the clustering of 3D head scans. A novel hierarchical algorithm was developed, in which a squared Euclidean metric was used to assess the head shape similarity of participants. A linkage criterion based on the centroid distance was implemented, while clusters were created one after another in an enhanced manner. As a result, 95.0% of the studied sample was classified inside one of the four computed clusters. Compared to conventional hierarchical techniques, our method could classify a higher ratio of individuals into a smaller number of clusters, while still satisfying the same variation requirements within each cluster. The proposed method can provide meaningful information about the head shape variation within a population, and should encourage ergonomists to use 3D anthropometric data during the design process of head and facial gear
Constitutive Modeling of Additive Manufactured Ti-6Al-4V Cyclic Elastoplastic Behaviour
Metal additive manufacturing techniques have been increasingly attracting the interest of the aerospace and biomedical industry. A particular focus has been on high value and complexity parts and components, as there the advantages offered by additive manufacturing are very significant for the design and production organisations. Various additive manufacturing techniques have been tested and utilized over the past years, with laser-based technology being among the preferred solutions â e.g. selective laser melting / sintering (SLM / SLS). Fatigue qualification, as one of the primary design challenges to meet, imposes the need for extensive material testing. Moreover, this need is amplified by the fact that currently there is very limited in-service experience and understanding of the distinct mechanical behaviour of additively manufactured metallic materials. To this end, material modelling can serve as a mediator, nevertheless research particular to additively manufactured metals is also quite limited. This work attempts to identify the cyclic elastoplastic behaviour characteristics of SLM manufactured Ti-6Al-4V. A set of uniaxial stress and strain controlled mechanical tests have been conducted on as-built SLM coupons. Phenomena critical for engineering applications and interrelated to fatigue performance (mean stress relaxation, ratcheting) have been examined under the prism of constitutive modeling. Cyclic plasticity models have been successfully employed to simulate the test results. Moreover, a preliminary analysis has been conducted on the differences observed in the elastoplastic behaviour of SLM and conventionally manufactured Ti-6Al-4V and their possible connection to material performance in the high cycle fatigue regime
Effects of Spin on Tennis Ball Aerodynamics: An Experimental and Computational Study
The aerodynamic behaviour of a tennis ball is very complex and significantly differs from other sports balls due to its surface structures (fuzz, seam orientation etc). Relatively high rotational speeds (spin) make the aerodynamic properties of tennis balls even more complex. Although several studies have been conducted on drag and lift in steady state condition (no spin involved) by the author and others, little or no studies have been conducted on spin effects. The so called Magnus effect on a sphere is well known in fluid mechanics. It is believed that the spinning can affect aerodynamic drag and lift of a tennis ball thus the motion and flight path of the ball. Therefore, the primary objectives of this work are to study the spin effects using both experimental and computational methods. In order to achieve these objectives, a series of tennis balls were used to measure their aerodynamics forces as a function of wind speeds, seam orientation and spins. The experimental study was conducted in the RMIT Industrial Wind Tunnel. A computational study of a simplified tennis ball was also studied using commercial software âFLUENTâ. The CFD results were compared with the experimental findings. Flow around the ball was visualised with smoke
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