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Heat Exchangers are widely used in many industries, such as chemical, food, air-conditioning system, petrochemical, oil, and thermal power plant. In the air-to-air and air-to-liquid heat exchangers for air-side heat transfer applications, special surfaces are often employed to obtain high rates of heat transfer. One geometry that can be used to enhances heat exchanger performance is a sinusoidally curved wavy passage. Wavy channels are easy to fabricate, and can provide significant heat transfer enhancement in the appropriate Reynolds number regime. This article offers a new method for calculating total heat transfer area in a plate-fin heat exchanger with waviness surfaces. Kays and London presented some experimental data to determine heat transfer area in wavy surfaces, based on the ratio of total heat transfer area / total volume. One of the important weakness of the method presented by Kays and London is calculating total heat transfer area is a chain process and depends on the other thermal properties of the heat exchanger. So, existence of a direct method can be helpful and , of course, a strong tool in optimization process.

The introduction of corporate government practices in Nairobi stock exchange saw the Bull Run that kicked off in the Nairobi Securities Exchange in the year 2006, which made the market gain more than 50%. As earnings of companies increased, so did the demand for shares by the public, corporate governance was incorporated as a strategy for the company success. The price appreciation forced many companies to split shares owing to the nature of majority of the Kenyan and foreign investors who wanted to invest in listed companies. Companies such as Kenol/ Kobil (Kenya Oil Company Limited), East African Cables Limited, CMC Holdings Limited, ICDCI (Centum Investments Company Limited) and Barclays Bank Limited that were highly priced opted to split shares to make them accessible to the public, and to benefit the company as well as potential investors. Corporate governance formulated and implemented legislation and enforcement procedure in place within the CMA and the NSE, to curb massive falsification of financial reports, conspicuous dealings in the NSE and illegal collaboration of stockbrokers with the intention to defraud investors. It is good corporate governance that even with the recent collapse of many stockbrokerage firms investor confidence in the capital corporate governance still is high. This study explores the contribution of the corporate governance on investor confidence in Nairobi Securities Exchange; recommend the possible solutions to curb corporate governance irregularities that lead to tremendous loss of investor money and confidence.

Conservation tillage (CA) systems are gaining increased attention as a way to reduce the water footprint of crops by improving soil water infiltration, increasing soil moisture and reducing runoff and water contamination. The concept of water footprint is defined as the total volume of freshwater used, directly or indirectly, to produce a product or process including the total amount of water required in agriculture for growing crops. About 141 million and 645 thousand hectares of land in the world have been destroyed by erosion because of inappropriate tillage operations. The total amount of 26 billion tons of soil eroded is estimated and about 2 billion tons comes out from Iran. Parallel to the erosion, loss of soil organic matter that occurs on to several factors, farming has become more challenging. Many strategies exist to combat soil degradation through erosion and compaction on agricultural fields. One of these strategies is conservation agriculture (CA). Reduced or no-tillage techniques, together with crop residue management and crop rotation are the pillars of CA. The term reduced tillage covers a range of tillage practices but it never involves inverting the soil. In this way, soil disturbance is minimized and crop residues are left on the soil. Studies in many European countries have shown that CA can indeed be very effective in combating soil erosion. However, soil and water conservation do not appear as main drivers in farmers’ decisions to shift or not to CA. Economic factors tend to be more important, but there are a lot of uncertainties on this domain. Studies show that production costs are mostly reduced, mainly by reduced fuel costs. Although many European studies have investigated the effect of reduced soil tillage on crop yields, a lot of uncertainties still exist.

This study focuses on a manufacturing process modification that can be carried out during the process of casting Aluminium-Silicon alloy in order to obtain desired properties and characteristics of a material for a particular usage. The effect of cooling rate was studied using sand and die moulds. Three types of mould were used namely dry sand mould, green sand mould and die mould .The result shows that the rate of cooling is faster in the die mould and the specimen obtained has the highest value of yield strength, ultimate tensile strength and hardness value but a low impact strength. The microstructure reveals that specimen A(dry sand mould) has a coarse microstructure, specimen B(green sand mould)exhibits a fairly wide spread distribution of silicon deposits while specimen C(die mould) exhibits fine and even distribution pf silicon deposits.

In this paper the Orlicz space of Hahn sequence of fuzzy numbers is introduced. Some properties of this sequence space like solidness, symmetricity, convergence free are studied. Some inclusive relations involving this sequence space are also obtained.

The study was carried out to investigate the influence of leadership styles and perceived organisational politics on work engagement. The sample for the study consisted of 120 participants with a mean age of 36.59 years. Fifty-Eight (58) of the research participants were males while 62 were females. Participants were randomly selected from the population of civil servants at the Governor’s office in Ado Ekiti, Nigeria; using the multi-level random sampling technique. Six hypotheses were tested. Results revealed that perceived organizational politics has no significant influence on work engagement. However, perceived organizational politics influenced the dedication and vigour dimensions of work engagement. Both autocratic and democratic styles of leadership independently and jointly influenced work engagement; and there was no significant interaction effect of leadership styles and perceived organizational politics on work engagement. There was no significant main and interaction effect of sex, rank, and age of employees on work engagement. There was a significant effect of sex of leaders on the use of autocratic style of leadership while sex of leaders did not influence democratic style and perceived organizational politics. Results of present study also revealed that there was a positive relationship between leadership styles and work engagement together with its subscales. Finally, there was a significant relationship between perceived organizational politics and autocratic leadership style but not on democratic style. Findings were discussed in line with previous research findings and it was recommended that organisations should not encourage or foster political behaviours that may hamper work engagement of employees; such as preferentially treating the employees. It was also recommended that the contingency approach to leadership should be encouraged in organizations, where the situation at hand will determine the type of leadership style to use and not just get fixed to a particular leadership style.

The tribal who were protecting the natural resources for the centuries are now being deprived of these natural resources for the development projects. The tribal area is full of natural resources which contains bauxite, iron ore, coal etc. these are required for the manufacturing industries. Deprivation of these natural resources are making them more vulnerable marginalized group. They become not only socially and economically marginalized groups but also physiological and cultural marginalized groups. The State is required to take ‘affirmative action’ to stop the marginalization of the tribal group. Generally the ‘affirmative action’ means as reservation policies for the marginalized groups in jobs. It is not the whole truth meaning of ‘affirmative action’. Any action of the State to minimize the difference between the advanced group of society and non-advanced group of the society is affirmative action. The Central Government has enacted a law titled as The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006 to reduce the pain caused to tribes by development induced displacement. This article will explore how The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006 is working as affirmative action for tribes. It will also enumerate the pain suffered by the tribes in the process of development projects.

Categories of intellectual capital is important that over last few decades that has attracted attention of academic circles. actually change the pattern of corporate and with the emergence of new challenges and compete in the global arena, companies to maintain their competitive advantage should be worth more to think as intellectual capital as a key factor companies to create value and sustain competitive advantage has become known then identification and reporting of intellectual capital issue importance for corporate managers and users of financial statements. In this study, the relationship between intellectual capital components and financial performance of listed companies in the cement industry Studied at the Tehran Stock Exchange. The study period is 2007 to 2011 years. For test the hypotheses and data analysis from method of least squares regression and neural networks are used. The results indicated a significant relationship between intellectual capital and corporate financial performance indicators. On the other research findings can be concluded between intellectual capital and financial performance of companies in the same (similar) craft approach to regression analysis and neural networks value added intellectual coefficient model Polic (VAIC) gives similar results however, the performance impact on capital employed human capital is a significant difference in performance.

The objective of our study was to search for the ultrasonographic afflictions of the metacarpophalangeal and metatarsophalangeal joints notably ultrasonographic synovitis , intra articular liquid accumulations , cartilaginous vascularisation as well as bone erosion and to compare them with the clinical aspects ( pain , swelling , limitations of mobility ) . MATERIALS AND METHODS : It was a transverse study ,comprising exclusively the cases of JIA corresponding to the criteria of ILAR 2001 . All the patients were clinically examined to look for pain , synovitis or articular limitations. Linear sound echography ( 14 MHz ) with doppler power , was used . The OMERACT criteria were utilised for evaluating the ultrasonograhic synovitis ; The software SPSS21 was employed as test statistic. RESULTS : 34 patients were included , with 612 joints . The mean age was 10,80 ± 3,29 . Total number of painful articulations of 31 ( 94% ) ; synovitic articulations was 4 ( 12 % ) ; total number of ultrasonography synovitis was 110 ( 18 %). In patients with normal clinical examination, ultrasound showed abnormalities in 159 (27 %) joints , the most frequent localization was at the MTP joints in 86 ( 54% ) p < 0,001.Presence subclinical synovitis for 73 ( 66 %) p< 0,001 . CONCLUSION : Our study detected subclinical synovitis ;this study suggests that ultrasound is an important supplement to clinical examination and should be performed in a systematic way to evaluate the activity of the disease. 

Zinc oxide nanoparticles doped with Vanadium of varying concentrations were synthesised by Sol-gel method. Samples prepared after annealing for 2 hrs at 600 oC are characterised by XRD,UV-Vis Spectroscopy, SEM and EDS. The hexagonal wurtzite structure is maintained in ZnO after vanadium doping at high concentration (15 at.%) as confirmed by X-ray analysis. The absorption edge of ZnO is red shifted by increasing the vanadium concentration. SEM shows the nanoparticle nature of the ZnO particle, molar concentration of dopants is confirmed by EDS analysis. The photo catalytic activity of Rhodamine-B dye solution under visible light is better for V-doped ZnO as compared to pure ZnO.