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The aim of this paper is to develop a probabilistic model for a cold standby system that consists of an imperfect switching device and a servicing facility. The model aims to address the issue of unexpected random failures of the switch by implementing preventive maintenance measures. The system has two identical units. It starts with one unit in active operation and another unit in cold standby mode. In standby mode the unit remains in perfect state. No failure is allowed in standby mode. As the operating unit fails, the standby unit needs to be switched into operation, to keep the system working. A servicing facility is present in the system to perform necessary servicing related tasks. The servicing facility referred to as the server, also takes care of all necessary remedial activities like preventive maintenance and repairs. The switch used as switching mechanism to place the standby unit into operation may found imperfect when needed. Similarly, the server too can fail while doing job. A preventive maintenance scheme is used for the switch whereas treatment is given to server. The method of semi-Markov process and regenerative point technique is used for model developing and solving, respectively. The expressions are derived to determine different system performance measures such as mean time to system failure, availability, busy period, expected number of preventive maintenances and the profit. The distributions of random time elapsed in repairs, replacements, preventive maintenances and treatments are general. This study highlights the usefulness of switch's preventive maintenance in long run. To study the asymptotic behavior of the system model, all the expressions for system performance measures are obtained in steady state. A simulation study is conducted using a presumed data set and assuming a Weibull probability distribution. The numerical results are shown in tabular form. The simulation results serve to highlight the significance of preventive maintenance for the switch. The findings of the paper can provide guidelines to the people engaged in designing, framing and implementing standby switching systems in real applications. [ABSTRACT FROM AUTHOR]

The complexity of engineering systems makes it challenging to keep them functional without failures for longer interval of time. This task is achieved by adopting effective maintenance strategies and appropriate structure design. So in such cases the functioning of service mechanism and chat of the server becomes essential. The server failure during any maintenance activity may lead to declined availability and hence the profit. In this paper we develop a probabilistic model for a standby system consisting of two identical units and a server subject to failure and treatment. The inspection of failed server reveals feasibility for treatment or replacement. The replacement time of server and switching time of standby is negligible. The failure, repair, inspection and treatment times are assumed as arbitrary. The model is developed using semi-Markov process and the steady state results of interests are derived using regeneration point technique of renewal theory and Laplace transfornations. The practical importance of the study is highlighted through numerical simulation, for a particular case. [ABSTRACT FROM AUTHOR]

To study the effect of subclinical and clinical mastitis on haematological, biochemical and mineral profile of crossbred cattle an investigation was carried. Haematology of animals revealed significantly (P< 0.05) higher average values of TLC in sub-clinically (9.20× 103/μl) and clinically (9.31× 103/μl) infected animals than healthy animals (6.87× 103/μl). Differential leucocytic count revealed neutrophilia and lymphopenia in clinical as well as sub-clinical mastitis (SCM). Biochemical estimations of plasma samples from sub-clinically and clinically infected animals revealed higher average values of TPP (8.44 g/dl and 823 g/dl), albumin (2.447 g/dl and 2.31 g/dl), globulin (5.82 g/dl and 5.93 g/dl) and fibrinogen (0.74 g/dl and 1.21 g/dl) compared with control group (7.44 g/dl, 2.94 g/dl and 4.41 g/dl and 0.60 g/dl, respectively). Mineral estimation revealed significant (P< 0.05) increase in calcium level in sub-clinical (13.45mg/dl) and clinical mastitis (13.149mg/dl) as compared to healthy control (9.44 mg/dl), however, no significant (P> 0.05) change was observed in inorganic phosphorus, Mg, Na and K levels. [ABSTRACT FROM AUTHOR]

A total of 132 buffaloes with history of pruritis, ulceration and exudation from ears were examined for ear sores. Flies were seen on body of all animals. Lesions were more concentrated around ears (132/132) with papular or pustular eruptions, exudation, excoriation, incrustation, alopecia, de-pigmentation and nodules. Ear lesions were more unilateral (94/132) as compared to bilateral (38/132). Distribution of other lesions were around eyes (25/132), on wither (16/132), teat and udder (9/132) of affected buffaloes. Impression smears and scrapings were collected from ears and other body lesions for diagnosis. Blood samples were collected from 10 ear sores affected buffaloes and 6 healthy buffaloes for haematobiochemical parameters. Impression smear revealed microfilaria, whereas scrapings revealed some microfilarial stages of StephanofUaria. It was confirmed as filiaria by expert and suggested for further investigations. Hemogram showed absolute eosinophilia. Biochemical parameters showed significant increase in globulin, whereas TPP, albumin showed significant decrease as compared to healthy buffaloes. [ABSTRACT FROM AUTHOR]

A total of 13 dogs of different age, breed and sex were presented with history of fight with snake and snake bite. Blood samples were collected for hematological parameters viz. hemoglobin, PCV, TEC, TLC, DLC, platelets and RBCs morphology and for biochemical parameters viz. ALT, AST, ALP, TPP, albumin, fibrinogen and CK. Blood clotting time was seen by capillary tube breaking test. The commonest presenting signs were salivation, vomiting, dilated pupils, absence of the pupillary light reflex, depression and generalized muscle weakness and respiratory distress. Mean Values of Hb, PCV, TEC and platelets were 12.5 ± 2.9 g/dl, 36.2± 4.1 percent, 5.92 ± 0.34×106/µl and 1,00,400 ± 1880/µl, respectively. Mean clotting time was increased 5.5 minutes in snake bitten dogs. Mean values of total protein, albumin, ALT, AST, ALP, CK and fibrinogen were 6.79 ± 2.56 g/dl, 2.9 ± 0.89 g/dl, 69.5 ± 8.42 u/l, 60.2 ± 4.8 u/l, 128.5 ± 26.7 u/l, 1184.5 ± 206.7 u/l and 600 ± 215 mg/dl, respectively. Area around the fang marks and wound was washed with potassium permanganate solution and dressed with povidine iodine. All dogs were treated by dextrose, normal saline, corticosteriods, antibiotics and tetanus toxoid. All dogs were treated with snake venom antiserum. In the present study out of 13 snakes bitten dogs 2 dogs died even after aggressive treatment. [ABSTRACT FROM AUTHOR]

Investigations were carried out during two consecutive Rabi seasons of 2014 and 2015 at the Experimental Farm of the Department of Seed Science and Technology, Dr Y S Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, India to study the spatial distribution of Brevicoryne brassicae in cabbage. One month old cabbage seedlings were planted in the field in the month of November during both the years. Distribution pattern of any insect population is an important aspect as it represents the interaction between individuals of the species and their habitat. Spatial distribution is useful for designing efficient sampling programmes for population estimation and development of population models. Spatial distribution is also important to understand the bioecology of the pest and to determine the sampling protocol for that species. In the present study variance to mean ratio (s2/ X),mean crowding (X*), ratio of mean crowding to mean (X*/X), 'k' of negative binomial, Taylor's power equation (s2 = 0.9099X1.55 during 2014 and s2 = 2.9861X1.1949 during 2015), Iwao's patchiness regression and optimum number of samples (Nopt) required to achieve the desired precision were calculated for different densities. Cabbage aphid, B. brassicae appeared in the fourth standard week i.e last week of January( 26.2 aphids/ plant during 2014 and 0.30 aphids/ plant during 2015) and persisted upto thirteenth standard week i.e last week of April ( 18.4 aphids/ plant during 2014 and 18.2 aphids/ plant during 2015) and followed a negative binomial distribution during both years. Optimum number of samples (Nopt) required varied with mean density as well as precision level. The present study will serve as basic information to develop a sampling plan of B. Brassicae in cabbage for its monitoring and management. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present study of stresses distribution and displacement in an isotropic hyperbolic rotating disk fitted with rigid shaft and having variable density parameter by using transition theory. It has been seen that the convergent disk made of rubber material requires a higher angular speed at the inner surface as compared to aluminum alloy material on the initial yielding stage, but for the fully plastic stage divergent disk requires higher angular speed at the inner surface as compared to a uniform/convergent disk. With the introduction of density parameter, the values of angular speed increase in the inner surface the initial/fully plastic stage. The convergent disk made of rubber material requires maximum radial stress at the inner surface as compared to aluminum alloy material. With the increasing value of density parameter, the radial stress increases in the intermediate surface of the hyperbolic rotating disk. Results have been discussed numerical and depicted graphically. [ABSTRACT FROM AUTHOR]