Search results

The purpose of this paper is to investigate the magnetic properties and the ground state phase diagrams of the double perovskite La₂NiMnO₆ using the Monte Carlo simulations (MCS).

In this work, the authors propose a Hamiltonian modeling this compound, described by an Ising model, with different exchange coupling interactions J11, J12 and J22 between the only magnetic atoms Ni and Mn.

Starting with the ground state phase diagrams, the authors present and discuss the stable configurations in different physical parameter planes. On the other hand, the authors present the investigation of the magnetic properties and the magnetization behaviors of the magnetic susceptibilities, as a function of temperature, crystal field, the exchange coupling interactions and the Zeeman energy. To complete this study, the authors illustrate the dependency of the total magnetizations for the hysteresis loops of the double perovskite La₂NiMnO₆ compound. This study is done for fixed values of temperature, the exchange coupling interactions and crystal field.

The authors modeled the different physical parameters of the double perovskite La₂NiMnO with a Hamiltonian describing the system. At T=0K, the authors discussed the ground state phase diagrams of different physical parameters planes. For non-null temperature values, the authors studied the magnetic behavior of the double perovskite La₂NiMnO using MCS under the metropolis algorithm. The authors expect that the results of these simulations can provide some important keys for the experimental research and technology applications of the double perovskite La₂NiMnO₆ in the future.

When the reinforced concrete beams are reinforced by bonding steel plates to the bottom, excessive use of steel plates will make the reinforced concrete beams become super-reinforced beams, and there are security risks in the actual use of super-reinforced beams. In order to avoid the occurrence of this situation, the purpose of this paper is to study the calculation method of the maximum number of bonded steel plates to reinforce reinforced concrete beams.

First of all, when establishing the limit failure state of the reinforced member, this paper comprehensively considers the role of the tensile steel bar and steel plate and takes the load effect before reinforcement as the negative contribution of the maximum number of bonded steel plates that can be used for reinforcement. Through the definition of the equivalent tensile strength, equivalent elastic modulus and equivalent yield strain of the tensile steel bar and steel plate, a method to determine the relative limit compression zone height of the reinforced member is obtained. Second, based on the maximum ratio of (reinforcement + steel plate), the relative limit compression zone height and the equivalent tensile strength of the tensile steel bar and steel plate of the reinforced member, the calculation method of the maximum number of bonded steel plates is derived. Then, the static load test of the test beam is carried out and the corresponding numerical model is established, and the reliability of the numerical model is verified by comparison. Finally, the accuracy of the calculation method of the maximum number of bonded steel plates is proved by the numerical model.

The numerical simulation results show that when the steel plate width is 800 mm and the thickness is 1–4 mm, the reinforced concrete beam has a delayed yield platform when it reaches the limit state, and the failure mode conforms to the basic stress characteristics of the balanced-reinforced beam. When the steel plate thickness is 5–8 mm, the sudden failure occurs without obvious warning when the reinforced concrete beam reaches the limit state. The failure mode conforms to the basic mechanical characteristics of the super-reinforced beam failure, and the bending moment of the beam failure depends only on the compressive strength of the concrete. The results of the calculation and analysis show that the maximum number of bonded steel plates for reinforced concrete beams in this experiment is 3,487 mm². When the width of the steel plate is 800 mm, the maximum thickness of the steel plate can be 4.36 mm. That is, when the thickness of the steel plate, the reinforced concrete beam is still the balanced-reinforced beam. When the thickness of the steel plate, the reinforced concrete beam will become a super-reinforced beam after reinforcement. The calculation results are in good agreement with the numerical simulation results, which proves the accuracy of the calculation method.

This paper presents a method for calculating the maximum number of steel plates attached to the bottom of reinforced concrete beams. First, based on the experimental research, the failure mode of reinforced concrete beams with different number of steel plates is simulated by the numerical model, and then the result of the calculation method is compared with the result of the numerical simulation to ensure the accuracy of the calculation method of the maximum number of bonded steel plates. And the study does not require a large number of experimental samples, which has a certain economy. The research result can be used to control the number of steel plates in similar reinforcement designs.

The purpose of this paper is to evaluate the current digitization levels of Korean libraries by identifying key elements of library services and measuring them for conventional vs digital approaches and use.

The study utilized previous research related to digital libraries and consultations with experts to arrive at 13 evaluation elements and components within them to analyze. For the purpose of this study specialized libraries, college and university libraries, and public libraries were surveyed, and their responses analyzed to rate their current digitization levels vs more conventional approaches.

First, after determining the elements that characterized the conventional and digital libraries by analyzing different pieces of literature and consulting with experts, 92 factors were identified for each of the conventional and digital elements based on the axis which was composed of 13 items. Second, this study indicated that the libraries obtained one of the conventional or digital characteristics independent of the situation, rather than that the digital library was more effective than the conventional library. Third, in evaluating the chosen libraries used as the examples, it was observed that the libraries had more conventional characteristics among the elements of the digital and conventional libraries. Also, based on the axis used for comparison of 13 items, elements such as the next generation service, the SNS service, and the library program service were more conventional, but elements such as classification and cataloging, acquisition, and the organization were more digitized.

This study is the first study in the world to measure the level of digitization of the library. Therefore, hereafter, each library will be able to measure and determine its digital position based on these elements. Up to now, some research was performed in pursuit of extracting the elements of a library but it had relied solely on literature review. Comprehensive research had never been performed as in this study.

Higher replacement rates often imply higher levels of absenteeism, yet even in generous welfare economies, employers provide sick pay in addition to the public sick pay. Using comparative population-representative workplace data for Britain and Norway, we show that close to 50% of private sector employers in both countries provide sick pay in excess of statutory sick pay. However, the level of statutory sick pay is also much higher in Norway than in Britain. In both countries, private sick pay as well as other benefits provided by employers are chosen by employers in a way that maximizes profits having accounted for different dimensions of labor costs. Several health-related privately provided benefits are often bundled. In both countries easy-to-train workers, high turnover and risky work are linked to less extensive employer provision of extended sick leave and sick pay in excess of statutory sick pay. In contrast, the presence of a trade union agreement is strongly correlated with both the provision of private sick pay and extended sick leave in Britain but not in Norway. We show that the sickness absence rate is much higher in Norway than in Britain. However, the higher level of absenteeism in Norway compared to Britain relates to the threshold for statutory sick pay in the Norwegian public sick pay legislation. When we take this difference into account, no significant difference remains.

By construction, income inequality measures employed in well-being analysis presume all individual differences to be deleterious to the social good. Yet some differences, for example, those acceptable to all and necessary for optimal resource allocation in producing that well-being, are demonstrably beneficial. Measured inequality is an amalgam of both deleterious or ‘Bad’ and beneficial or ‘Good’ differences, and from both policy and well-being measurement perspectives, distinguishing between types with measures fit for purpose makes sense, especially if the types are taking different paths. Here, as an exemplar, the distinction is explored in considering the progress of human resource, gender, and immigrant status-based personal income differences in twenty-first-century Canada. Categorising human resource-based differences as efficiency promoting ‘Good’ inequalities and gender and immigrant status-based differences as discriminatory and ‘Bad’ reveals that, under all proposed measures, while aggregate and ‘Good’ inequality grew over the sample period, ‘Bad’ inequality diminished, reinforcing the case for inequality measures that are fit for purpose.

To determine the factors that motivate rural households to supply ganyu labor and to estimate its impact on food security.

Data from the 2010/2011 Malawi household survey were used. A probit model to evaluate the determinants of ganyu labor supply and a propensity score-matching estimator to assess its impact on food security were used.

Less educated males are more likely to supply ganyu labor. Ganyu labor supply increases with household size, while it decreases with the level of crop farming and size of land owned. Results from the average treatment effect indicate a positive and significant impact of ganyu labor participation on the number of meals consumed per day.

Ganyu labor participants in Malawi have better access to food as a result of cash income from ganyu. Government support mechanisms such as minimum wage regulations should consider the welfare of ganyu labor participants.

This paper assesses the effect of property titling on child labor. Our main contribution is to investigate the potential impact of property rights on child labor supply by analyzing household response regarding the child labor force to exogenous changes in property ownership status. The causal role of legal ownership is isolated by comparing the effect of land titling using data from a unique study in two geographically close and demographically similar communities in Osasco, a town of 654,000 people in the Sao Paulo metropolitan area. Survey data were collected from households in both communities before and after the granting of land titles, with neither type knowing ex ante whether it would receive land titles. The econometric estimates, applying the Difference-in-Difference (DD) methodology and propensity score matching, suggest that land titling decreases child labor.