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Small air conditioning units are usually used for small and medium scale residential buildings. Therefore, more energy efficiency and lower cost are needed along with reliable control for the air conditioning units. An experimental investigation has been carried out to study the performance of a direct expansion air conditioning unit under abnormal surrounding ambient conditions. To facilitate variation of refrigerant flow rate according to the evaporator load, a suitable thermostatic expansion valve and liquid refrigerant reserve was used. The influence of evaporator airflow and its temperature on the air conditioning unit performance and compressor power consumption has been investigated. The performance of air conditioning unit is simulated using the TRANSYS Simulation Program. The model is validated by real operating data from the system. It has been found that a 14.28 % reduction in compressor power consumption is achieved by decreasing the condenser inlet air temperature from 50 to 35 ºC. The cooling capacity of the evaporator was increased by 32.2 % with decreasing the condenser inlet air temperature from 50 to 35 ºC, Also it was increase by 7.56 % with increasing the evaporator entering air volume flow rate from 300 to 600 m3/hr. It can be concluded that the COP increases by 19.84 % with increasing the condenser inlet air temperature from 50 to 35 ºC. The modeled results of the air conditioner’s COP show agreed well with the corresponding measured data, the uncertainty was within ±11.9 %.

The purpose of present study was to explore and to compare public and private biology teachers’ views about use of audio visual aid in teaching of Biology at secondary school level. The data for the study was collected from secondary schools teachers of biology. The results of present study show that there is a positive relationship between facility of audio-visual aids and the teacher’s attitude. The findings report that secondary schools teachers of biology do realize the importance using audio visual aids in teaching of biology. However, finings reported that teachers of public sectors were more familiar about the importance of use of audio visual aids for teaching of biology than private sector teachers. It was concluded that in public sector school all teachers were trained as only trained teachers were appointed at public sector schools at secondary level. Finding further reported that there were no proper facilities of audio visual aids for biology teaching. Results further inferred that utilization of audio-visual aids in teaching of biology was very effective as it increases the level of interest and enhances motivation for learning in students and the only visual aid available at maximum secondary school was black board.

This work aimed to apply a thermochromatic polymer based on 10,12-pentacosadiynoic acid (PCDA) monomer as a temperature sensor. This polymer has specific chemical structure enabling it to vary its color parameters, namely CIE L (brightness), a (red-green) and b (yellow-blue), with the temperature transitions. These color parameters were calculated in accordance to the American standard ASTM number E308-2001. All changes in the temperature were found to be easily tuned with the visual color and the color difference (DE). These changes were found to be recyclable and reversible in the studied temperature range of 25-105^oC with regression factor equals unity.

The solid phase FTIR and FT-Raman spectra of 4-chloro-2, 6-dibromoaniline (CDBA) have been recorded in the region 4000-400 cm-1 and 3500-100 cm-1, respectively. The spectra were interpreted with the aid of normal coordinate analysis following a full structure optimization and force field calculation based on the density functional theory (DFT) using the standard HF/6-31+G(d,p) and B3LYP/6-31+G(d,p) methods and basis set combination. A close agreement between the observed and calculated frequencies by refinement of the scale factor. The values of electric dipole moment (? and First-order hyperpolarizability(?) of the compound were computed using ab-initio quantum mechanical calculations.The calculation results also show that the PFA molecule might have microscopic nonlinear optical (NLO) behavior with non-zero values. HOMO and LUMO energy gap explains the eventual charge transfer interaction taking place within the molecule.

In this paper, the authors propose a voter-customer brand loyalty model using a mixture of associative network memory model, brand signalling theory and social identity theory. The model will describe the behavioural influences of the political celebrity credibility, the political party brand credibility and the political party brand image on the brand equity of the party presidential candidate, voter-customer-party identification and the voter-customers loyalty. In this model, the authors propose that credible political celebrity endorsement can effectively enhance the brand equity of the party presidential candidate and the brand credibility of the party. In addition, the brand credibility of the party may enhance the brand equity of presidential candidate. In sum, the model framework will show that the use of credible endorsers and investment on the enhancement of the party brand image will lead to enhanced brand equity and committed meaningful relationship with the party presidential candidate by voter-customers.

Mullerian abnormalities are made of a group of different congenital anomalies of the female genital system. The aim of this article is to juxtapose the normal development of the uterus with the abnormal development so a clear understanding of the cause of congenital anomalies of the uterus can be generated and correlated with the clinical significance.

Double aortic arch is class of congenital anomalies caused by a chromosome band 22q11 deletion, which are often referred to CATCH-22 syndrome or chromosome band 22q11 deletion syndrome using the unified terms. it is responsible for formation of Double aortic arch ,both right and left aortic arch arise from the ascending aorta common form of complete vascular ring, encircling both the esophagus and trachea are compressed by the aortic arches and their derivatives, resulting in non-cardiac morbidity. This study aimed to through an insight on the embryological basis, its clinical and surgical implications on the double arch aorta.

The purpose of this study is to compare organizational learning, organizational performance, and electronic human resource management in the water department staff of Tehran and Kermanshah provinces. Given its purpose, this study is an applied research, in which questionnaire is used to measure the variables. After measuring the content validity and reliability (the Alpha coefficient of electronic human resource management (0.7), organizational learning (0.8), and organizational performance (0.75)), the research tools were distrusted among the statistical population, i.e. the questionnaires were distributed in a sample of 240 individuals (120 persons from the staff in Tehran province and 120 persons from the staff in Kermanshah province) consisting of all experts of water department in Tehran and Kermanshah provinces. The statistical method of multivariate variance analysis (MANOVA) was used to analyze the data. The research results indicated that among all the variables and their components, there is a significant difference only in the information acquisition and creation component of organizational learning between the two groups, and there is no difference in other components. Finally, according to the results obtained, some suggestions have been presented to future researchers.

The major challenges in automatic multimodal image registration are the in consistency in intensity (or) contrast patterns and the existence of non overlapping regions between images. Also presence of high non-homogeneous image contrast makes it very difficult to compare the image contents. The proposed method is using a phase representation derived from Dual Tree Complex Wavelet Transform as similarity metric for registering multimodal images. This method uses a transformation that minimizes the residual error between phase representations of two multimodal images. Sub pixel level local optimization techniques are used to improve the stability in handling situations like small initial overlapping between images. This method has been tested on various multimodal images. This technique has better accuracy than existing registration techniques even in the presence of image non-homogeneity and inconsistency in intensity patterns.

We proposed a new status based clusterhead election algorithms for mobile ad hoc networks which are responsible for stable clusterhead election for a cluster and maintain a stable clustering by predicting staying time for a cluster and selecting an optimal clusterhead. In proposed method if there is two or more than two cluster heads are within the same radio range, initially clusterhead changes will be delayed up to delay timer. After delay timer expire if both the cluster heads are still in the same radio range, then old new clusterhead change its status from 0 to 1 and become as Clustermember within same cluster. In proposed method old clusterhead within the cluster has priority to act as clusterhead compared to other clusterhead which is coming from other cluster.