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A bus transfer system is designed to provide process continuity to the loads attached to a motor bus while transferring the bus from one source to another. A successful bus transfer under contingent conditions provides immense value and benefits to continuous process operations that cannot afford an interruption of power supply to plant auxiliaries. This paper describes some real-world bus transfer requirements, implementations, and experiences in thermal power plants and continuous process industry plants. The fast, in-phase, residual voltage, and momentary paralleling transfer methods are described, compared, and evaluated. The spin-down characteristics for different motor buses are analyzed, and the feasibility of the different transfer modes is deduced. Auto- initiation criterion for bus transfer is explored, using a combination of bus undervoltage, underfrequency, and (df/dt) characteristics. Different integrated system requirements, such as monitoring of readiness conditions, breaker failure detection and corrective action logic, and online testing measures, are discussed. The results of the resultant 'hot' load trials and their benefits to the system are explained and interpreted. The concept of islanded transfer for grid-free operations of captive generation-load systems is discussed and elaborated. Index Terms--Automatic bus transfer (ABT), bus transfer system (BTS), continuous process, fast, in-phase, islanding, residual voltage.

This paper concerns the addition of the few critical elements of a protection system to the Electromagnetic Transients Program (EMTP), which is one of the most widely used programs for the simulation of transients in power systems. It contains models for almost every major power system component. A protection system consists of instrument transformers, relays, and circuit breakers. Models for current transformers (CTs) and capacitor voltage transformers (CVTs) are developed, validated, and incorporated in the EPRI/DCG EMTP Version 2.0. The user can define the values of the CT and CVT parameters. Total FORTRAN capability has been added to the EMTP; new subroutines and an inbuilt structure to allow the linking of user-defined FORTRAN subroutines with the main EMTP are explained. This capability is necessary to simulate computer relay algorithms. The outputs of the algorithms can be passed to the EMTP, which enables the study of the dynamic interaction between the power system and the protection system. The FORTRAN capability can also be used to develop models for relays. Models of specific relays, such as those for line protection (CEY51A and SLY12C) and transformer differential protection (D202 and BDD15B), are also available. The relay models can be used with different settings. These new features in the EMTP together constitute the critical elements of a protection system. Thus, it is now possible to simulate the dynamic interactions between a power system and a protection system.

Capacitor banks are applied in power systems to provide reactive power. The reactive power results in lower current in lines upstream of the bank improving system voltage and power factor and reducing line losses. Capacitor banks can be configured as filters for harmonic reduction. The protection systems for capacitor banks include fuses, surge arresters, and protective relays. This paper will focus on protective relaying philosophies of grounded and ungrounded Y-connected shunt capacitor banks, which are commonly applied on industrial and utility power systems. Index Terms--Capacitor bank overcurrent protection schemes, capacitor bank protective relaying, capacitor bank unbalance protection.

Introduction: Vitiligo is an acquired depigmentary condition caused by inactivation or destruction of melanocytes in epidermis and hair follicle. Worldwide incidence of 1% has been reported; similar to various dermatological clinics in India. Widespread prejudice, ignorance, taboos, lack of scientific appraisal, and confusion of vitiligo with leprosy makes it an immense psychological stress. Aim: To know the clinical profile of vitiligo patient with associated cofactors. Materials and Methods: Total 1,010 patients of vitiligo attended in outpatient department at Shree Krishna Hospital (SKH) and Matar camp, Gujarat over 1 year period from August 2011 to July 2012 were included in this study. Detail history and clinical examination of patients were done. Results: Out of 1,010 patients 57.3% were females and 42.7 % were males. Most cases developed vitiligo by 2nd decade of life. Progressive course was found in 60.9 % of patients. Vitiligo vulgaris (57.8%) was most common morphological type. Most common site of onset (41.5%) and involvement (75.7%) was lower limb. Family history was present in 20.4%. Conclusions: Vitiligo constitutes important dermatological disease especially in India. The data suggest that local epidemiological behavior of vitiligo need not be the same across different regions. Vitiligo differs substantially in various clinical aspects. [ABSTRACT FROM AUTHOR]

This paper addresses the subject of reducing outage durations and autorestoration applications within the distribution substation. Employment of intelligent electronic devices (IEDs) can aid in the reduction of the fault duration time, and also it enhances the protection, control, and monitoring at the distribution level. Further, communication among these IEDs can provide faster autorestoration, remote data analysis, event recording, etc. Many recent issues related to distribution substation protection are discussed and techniques to address these issues using current technologies are proposed. [ABSTRACT FROM AUTHOR]

Sweat gland adenocarcinoma is a rare tumor particularly over scalp. They have potential to be benign as well as distant metastasis. Usually presents with papules or nodules. Ulcerative morphology is uncommon. Wide surigical excision with regional lymph not dissection is the treatment of choice. A 42-year-old female with sweat gland adenocarcinoma of scalp is reported with cervical lymph node involvement. [ABSTRACT FROM AUTHOR]

Pretibial myxedema (PM) is an infiltrative dermopathy which is seen in grave's disease. It is also associated with hypothyroidism, but is infrequently seen in Hashimoto's thyroiditis. Lesions are seen commonly over pretibial region as non-pitting oedema or with a plaque morphology. Heat shock protein (HSP) has been reported to be expressed by fibroblasts present at affected site, which cause lesions of PM. Histopathology differentiates it from other dermatoses. Lesions usually resolve spontaneously, but therapies like potent topical steroids, intralesional steroids, gamma globulin, pentoxifylline, surgery and radiotherapy are indicated. Here, a case of PM with euthyroid Hashimoto's thyroiditis has been reported, which was proven by histopathology. [ABSTRACT FROM AUTHOR]