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In the present paper the system considered consists of two subsystems A and B. Subsystem A consists of identical operating and warm standby units. While subsystem B has two dissimilar units: main unit and a unit in cold standby. Main unit of subsystem B is assumed to be more efficient than the standby unit so when the main unit fails the system goes to the state of low efficiency. Main unit is connected to cold standby unit with a switching over device. Further, whenever there is a failure in one of the units of A and in the main unit of subsystem B, the system goes to critical state where system has to stop functioning to avoid the further failures. Also we have considered that the company providing repair facility has appointed a repairman. The repairman repairs the system in case of minor failures but when the system fails completely he has to take it to the nearest service station of the company for repair. By applying Supplementary variable technique, Laplace transformations and copula methodology transition state probabilities, asymptotic behaviour, reliability, availability, M.T.T.F., cost effectiveness and sensitivity of the system have been determined. Particular cases corresponding to the situations when the standby unit of subsystem A is in cold standby and in hot standby have also been considered. At last some numerical examples have been taken to illustrate the model.

Minimum weight spanning tree is a well known graph optimization problem, which has a wide range of applications in telecommunications and routing problems. The problem considered in this paper is to find the second minimum weight spanning tree for a given network. A new algorithm is proposed and its computational complexity is discussed with numerical illustrations.

A Common effective method i.e. base isolation systems is used to reduce the seismic response of liquid storage tanks. In this work a method for dynamic analysis of liquid storage tanks isolated by the lead rubber bearing to bi-directional earthquake motion which incorporates the interaction between the restoring forces of the bearings in two orthogonal directions is presented.it is concluded that. The peak response of base isolated liquid storage tanks is not much influenced by the bi-directional interaction of restoring forces of Lead LRB.

This study aims to identify whether the shifting from Human resource management to strategic human resource management in the leading industries of Iran has passed its’ fundamental alteration. Statistical Population covers 45leading manufacturing organizations from three pioneer industries, comprising 1280 employees including, senior managers, and members of strategic committee, board of directors, department managers, line managers and staff experts. Sampling method is random and classified. 619 questionnaires out of totally 712 samples has returned (87% return rate). Research methodology is a descriptive survey in the field study. Results show that strategic human resource management in pioneer industries of Iran is not in a desirable status. It requires a foundation and intention to cultural, social and theoretical components so that concept of diversity from traditional human resource and staff management to strategic human resource management can be provided.

This study investigated skills acquisition in Chemistry education for youth empowerment. A descriptive survey design was adopted. The population of the study was made up of two thousand, one hundred and nine (2,109) senior secondary (III) Chemistry students in the 14 Government owed secondary schools in Obio-Akpor Local Government Area of Rivers State. The two hundred (200) senior secondary (111) Chemistry students used as sample were obtained from five schools with fairly equipped science laboratories that could sustain most of the practical prescribed in the senior secondary school chemistry curriculum. Purposive sampling was used to select the schools as well as one intact class in which all the students offer chemistry in each school. The instrument for data collection was a structured questionnaire of thirty-five (35) items divided in three sections (a , b and c) which elicited information on the extent of use, availability, usability and the influence of the innovative teaching methods that enhance skills acquisition in Chemistry. It also elicited information on the skills acquired by the Chemistry students. The instrument was validated by 2 experts in science education (one biology and Chemistry options), as well as an expert in test and measurement.. A reliability coefficient of 0.76 was obtained using a test-retest method to obtain data and Pearson Product Moment correlation statistics.. In order to make decisions, a mean reference of 2.5 on a Modified 4 points Likert Scale was used. The result showed that students learnt better and acquired scientific skills when the teaching methods allowed active participation and interaction with the learning materials (hands on Activities). The result also revealed that students were able to acquire acquisitive and communicative skills. Sequel to the findings, the study recommended that the teaching-learning interaction in chemistry should be activity-oriented for the development of skills useful for enhancing productivity.

The research was conducted to identify types of aquatic macrophytes that grow in and around reservoirs, their uses, and the impacts of the macrophytes on fishing communities at Bontanga, Golinga, and Libga reservoirs, the Buipela dam, and the Black Volta at Buipe in the Northern Region of Ghana. The principal methods were ocular observation, photography and semi-structured interviews using questionnaires. The predominant macrophytes identified and their uses were: Vossia cuspidata, Elodea canadensis, and Echinochloa stagnina used as fodder for livestock; shoots of Ipomea aquatica, Panicum hemitomon, and Phragmites karka were used as roofing material, and for making hats, mats and necklaces; Nymphoid indica, Nympheae lotus, Elodea canadensis, Alternanthera sessilis, Pistia stratiotes and Hydrocharitaceae spp were being used to treat stomach ulcer, rheumatism, malaria, flu and boils; Ludwgia stolonifera and Ludwigia peploids were used as feed and as food for human consumption. Eichhornia natan and Triglochin dubia were identified without any known uses. It was also observed that the macrophytes impeded fishing operation at the study areas by entangling the fishing net of the fishermen. Exploding masses of macrophytes such as Ludwgia stolonifera were observed to redirect paddling, making fishing operation tedious. Nevertheless, some of the macrophytes were being used as bait to catch fish and as soap (Ludwigia peploid) to wash fishing gears. Sustainable use of the reservoirs require active mechanical, chemical, biological, or integrated control methods and the commercial exploitation of the macrophytes for production of useful products in local industries.

An efficient approach for producing electricity from the abundant energy of the sun is discussed. The Nantenna Electromagnetic Collectors (NEC) [1] devices target mid-infrared wavelengths, where conventional photovoltaic (PV) solar cells are inefficient and where there is an abundance of solar energy. The initial concept of designing NEC was based on scaling of radio frequency antenna theory. This NEC is basically a Nano antenna which collects the sun radiation and thermal radiation and converts it into electrical signal. The aim is to realize a low-cost device that will collect and convert this radiation into electricity, which will lead to a wide spectrum, high conversion efficiency, and low-cost solution to complement conventional photovoltaic (PV) solar cells.

Zinc oxide nanostructure were successfully synthesized by chemical method and deposited on Al2O3 substrate using PLD. XRD analysis demonstrated that the ZnO nanostructure has a wurtzite structure with orientation of (002). SEM results indicated that by increasing the calcined temperature, the dimension of the ZnO nanostructure increases. The optimum temperature for synthesizing high density ZnO nanostructure was determined to be 1250 K. Room temperature PL spectra of the ZnO nanostructure showed a strong UV emission peak located at around 380 nm and a relatively weak green emission at around 540 nm, confirming that the as-grown nanorods possess good optical properties. The sensitivity of zinc oxide NRs films to 50 ppm vapor NO2 gas as a function of working temperature with different doping.

Hydrazone compounds derived from 2–Amino –5–chlorobenzophenone. The structures of the compounds are purified and characterized by means of TLC, melting point, IR, 1H NMR spectral data. The antimicrobial activity against bacteria and fungi was studied. The result of preliminary biological tests showed that of these compounds possess biological activaties.

The purpose of this study is to survey the perception of teachers towards headmistress’ leadership dan recognize the level of motivation among teachers in that particular school. This study is modelled in qantitative and descriptive manner which involves 20 randomly chosen teachers in a primary school in Batu Pahat district under a headmistress leadership. Questionaire is used as an instrument to identify the work structure in women leadership, leader’s compassion and teachers’ level of motivation. In this study, descriptive analysis namely mode, min and percentage is used to in study outcomes. The study outcome that on the whole, teachers’ perception towards headmistress leadership in primary school in the district of Batu Pahat is positive ans satisfactory. The min score for all respondents for all items in the questionnaire is 4.07. The value shows basically these respondents have positive and constructive perception towards leadership of a headmistress. Nevertheless, there is a significant association between teachers’ motivation level and perception towards leadership of a headmistress. This verifies that the higher the teachers’ perception towards leadership of a headmistress, the more elevated their level of motivation. This study supports the outcome pertaining general assumption that the leadership style of a headmistress indeed influences teachers’ working motivation level.