Archives-August 2014

This study wishes to examine and validate the ‘broken window’ hypothesis among the fifty one states in the United States. The chosen method for this analysis is Johansen cointegration test to test for cointegration, and if any cointegrating vector is found, we proceed to test for Granger causality based on VECM. We test whether property crime (proxy for minor crime) leads to violent crime (proxy for major crime) in the fifty one states with respect to the period 1960 to 2007. Result of the study indicates that violent crime and property crime are cointegrated in forty eight states out of fifty one states. Further analysis to test for the validity of the broken window hypothesis provides stunning result whereby we found that the hypothesis is indeed valid in forty four out of forty eight states.

Occupational stress according to the current World Health Organization's (WHO) definition "is the response people may have when presented with work demands and pressures that are not matched to their knowledge and abilities and which challenge their ability to cope”. While planning for stress intervention a combination of organizational change and client centered stress management is often the most useful approach for preventing stress at work. Both organizations and employees can employ strategies at organizational and individual levels. This article tries to provide conceptual understanding on occupational stress and effectiveness of occupational stress interventions with trying to provide evidence for the effectiveness of stress interventions.

The design of existing cycle rickshaw has hardly changed significantly even since it was introduced in India in early 1940’s from Far East. The gearing and the mechanical advantage of the pedal is very poor. Hence the rickshaw puller has to work hard while climbing even a slight slope. A common sight is of the rickshaw puller getting down and pulling on the foot the rickshaw with the passengers. The conventional drive mechanism of tricycle is provided with one set of sprocket, which gives speed ratio of two between input and output. This speed ratio is fixed for all loading conditions. More effort is required to the puller in starting from the rest or going up. The work done by the various researchers has been studied and improved methodology has been suggested by the authors in future work.

Pedagogical content knowledge (PCK) has become a framework for exploring what teachers need to know or to develop for effective teaching. Physics teachers’ PCK includes five components. In this study, the self-made “Questionnaire of Physics Teachers’ Pedagogical Content Knowledge” was used. The quantitative responses were compiled and analyzed by SPSS. The results indicated that the physics teachers’ level of PCK is on the intermediate and many factors help physics teachers to develop their PCK.

Pedagogical content knowledge exerts significant driving influence in educational research of teachers. PCK is a basic guarantee for teachers to become expert educators. For physics teachers, PCK is a knowledge synthesis which is developed in a specific teaching situation. PCK development of physics teachers needs the accumulation of time and experience. There are many methods to develop physics teachers’ PCK, such as self-study, teaching reflection and school-based educational research.

The main purpose of the current research is evaluating the effect of successful implementation of information systems on firms’ performance; case study is Bojnourd Cement Company during 2001 to 2004. Productivity, managers’ decision-making process, information quality, and human resources are considered as variables of the study. Research method is of questionnaire type, using general and professional questions in Likert scale. Research type, in terms of aim, is considered as applied research type. For data analysis, descriptive and inferential statistics is used. In inferential statistics-part of the study, to answer and to make decisions regarding study hypothesis as well as generalization of them to the statistical population under investigation, various tests such as one-tailed Student's t-test, one-tailed variance analysis test and Duncan Compare Means Test is used after converting study variables from ordinal scale to interval scale. The results of the study indicate that implementation of a successful accounting information system is effective on all performance components except productivity.

The removing dye from wastewaters is a main concern in textile industries letter, press and other commercial manufacturing systems in this decade. This process can make our environment polluted and endanger human being health as they are poisonous and have negative effects on human body. This review paper firstly recognizes synthetic pollution, its characterization and poisonous particles; then, it presents several improvements regarding optimum methods for treating and removing dye from wastewater and finally it suggests some adsorbents that are bio-based and money-saving. A comprehensive category of adsorbents including agricultural waste, bio and natural materials and industrial waste were reported. This paper suggests adsorption method using bio-waste adsorbent as an acceptable method in order to remove dye from waste water. However, further studies are needed to scrutinize the precise results of this approach in industry.

The objective of the present study is to investigate thermal diffusion and radiation effects on unsteady MHD flow past a linearly accelerated vertical plate with variable temperature and also with variable mass diffusion in presence of heat source or sink under the influence of applied transverse magnetic field. The fluid considered here is a gray, absorbing/ emitting radiation but a non-scattering medium. At time t>0, the plate is linearly accelerated with a velocity in its own plane. And at the same time, plate temperature and concentration levels near the plate raised linearly with time t. The dimensionless governing equations involved in the present analysis are solved using the closed analytical method. The velocity, temperature, concentration, Skin-friction, Nusselt number and Sherwood number are discussed through graphs in terms of different physical parameters like magnetic field parameter (M), permeability parameter (K), radiation parameter (R), Schmidt parameter (Sc), Soret number (So), Heat source parameter (H), Prandtl number (Pr), thermal Grashof number (Gr), mass Grashof number (Gm) and time (t).

Bitumen is a hydrocarbon material that accumulates near the earth's surface in the form of asphalt springs or in other forms under the act of hydrostatic pressures of oil reservoirs, it will form bitumen mines after undergoing polymerization process. This mineral (organic) matter is in close relationship to oil reservoirs present in the area, i.e. when oil moves or migrates from one place to another place some part of it will be separated and will remain in the form of streaks, lenses and etc. In this work, the exploration of bitumen resources in Saleh-Abad area, Ilam is carried out using geoelectrical data that were gathered in two-dimensional form, exploration drilling data and also geological data. Today the best method for underground studies and mineral explorations is geophysical studies and drilling exploration wells meanwhile. One of the best data acquisition methods in the Geoelectricity is two-dimensional data acquisition or in other words electrical imaging in two dimensions. Tomography or electrical apparent resistivity tomography is a geophysical technique that investigates underground structures in two or three dimensions. The advantage of ERT method in comparison with other traditional and routine methods is that it investigates the changes of electrical apparent resistivity either laterally (constant spacing traversing or CST) or vertically (vertical electrical sounding, VES) in space. Geophysical data acquisition of the mentioned mine was done using dipole-dipole array in two profiles upon which some points were proposed for exploration drilling. Exploration drilling was done in powder method on the geophysical profiles in six 15-meter bores which proved the high precision of apparent resistivity method for bitumen exploration. Interpretation and modeling of two profiles was carried out using RES2DINV and modeling of drilling Logs was done using LOGPLOT that both had a good conformity with geological data and surface outcrops.

Reactive Distillation (RD) is the combination of chemical reaction and distillative product separation in single piece of equipment, offers a number of specific advantages over conventional sequential approach of reaction followed by distillation or other separation techniques. The experimental part includes RD experiments in laboratory scale, carefully evaluated database for describing chemical reaction and phase equilibria. The iso-amyl acetate synthesis is also carried out in a packed bed RD column operated in batch and continuous modes. This paper describes an investigation into experimental and simulation work of the heterogeneous esterification of acetic acid with iso-amyl alcohol, catalyzed by an acidic cation –exchange resin. The effects of the variables such as the reflux ratio, vapour rate and feed flow rate on iso-amyl acetate synthesis are studied experimentally. The simulations are based on the equilibrium-stage model approach. The simulation studies are performed in Aspen Plus and MATLAB. Finally results of sensitivity studies using Aspen plus are presented to show the optimum performance of RD column.