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Purpose This paper aims to propose Hidden Converter (H-Converter) combined with dual port 3Ø inverter for energy storage application to produce wide range of voltage. Some of the application required wide range of voltages, but problem from E-chopper is either boost or buck mode of operations, both modes are not possible. To overcome this drawback, H-Converter is combined with dual port 3Ø inverter controlled by carrier-based pulse width modulation (CB-PWM) technique is added with zero sequence injection. Design/methodology/approach Hidden converter is a bidirectional DC-DC chopper used to convert fixed DC to variable DC and vice versa in both buck and boost modes of operations. Dual port inverter is combined with hidden DC-DC converter can produce wide range of voltages. Findings The bidirectional DC-AC converter requires less power for processing and consumes less power losses by using modest carrier built- pulse width modulation scheme through proposed zero structure addition. Originality/value By using this proposed strategy H-Converter can produce wide range of voltage in both the sides and mostly power is processed in the 3Ø inverter with a one stage conversion with less power loss. As a result, with one stage power conversion has more efficiency because of less power loss. This proposed converter has designed by analysis, and the real time result is tested in an experiment.

This novel converter proposes a Multiple Input and Multiple Output (MIMO) power conversion approach for step-up and step-down processes in AC-DC, DC-DC, AC-AC and DC-AC conversions. This versatile converter is designed by using power electronic switches, for AC-DC and AC-AC conversions thyristors are preferred, whereas DC-DC and DC-AC operations require both turn-on and turn-off control so that transistor (IGBT) is the most suitable switch. The proposed converter is highly recommended for multiple source and multiple output operations, but it can perform one conversion at a time. Power rating of the converter can be up to kilowatts during DC-DC and DC-AC conversions process and AC-AC and AC-DC conversions rating may extend up to megawatts. Simulation model of the MIMO converter is examined in the MATLAB simulink model and the same verified in the real-time test bench model. Conversion in all the stages can be controlled by a digital controller according to the requirement. All four conversions can perform step-up as well as step-down process, so design of inductor and capacitor values are very much important. All four modes of operations for thyristor-based transistors and two diode-based transistors are used to ensure switching operations. Novelty of the research work is conversion of power in all the modes can be bidirectional and also in single-stage process, but in the existing systems of power conversions is a unidirectional process. Proposed single-stage power conversion has more efficiency because of low switching losses. This proposed converter was designed by using mathematical analysis, tested at simulation level and verified in the real-time experiment.

Plasma cell granuloma is a rare reactive tumor- like lesion composed of polyclonal plasma cells. It primarily affects the lungs but occurs in other anatomic locations such as orbit, paranasal sinuses, larynx, tonsils, ears, tongue, lip, oral cavity and gingiva. A 65- year old female presented with the chief complaint of swelling over the right upper gingiva and mobility of right upper 2nd and 3rd molar teeth since 3-4 months At histopathology due to presence of uniform population of plasma cells a histopathological diagnosis of plasma cell rich lesion was made with a differential diagnosis of extramedullary plasmacytoma and plasma cell granuloma. However, immunohistochemical staining for kappa and lambda chains showed a polyclonal process and antibodies to CD138 were strongly positive, confirming the diagnosis of plasma cell granuloma. The case describes a rare condition of plasma cell granuloma occurring at an unusual site. Authors also emphasize the importance of immunohistochemistry in differential diagnosis of plasma cell rich lesions.

Epithelial-Myoepithelial Carcinoma (EMC) is a rare low grade epithelial malignancy of major Salivary Glands (SG). Though the histomorphology of this tumor is distinct, unusual location and clinical presentation may pose diagnostic difficulties especially when this lesion is first encountered at cytology. We report a case of 60-year-old female presenting with nasal obstruction of three months duration. At FNAC the diagnosis of EMC was suggested and it was confirmed on histopathology. We present this case highlighting the cytomorphologic attributes of this rare tumor occurring at an extremely uncommon location - Nasal cavity.

Tuberculosis (TB) and cancer are two lethal diseases causing significant morbidity and mortality in developing countries like India. Co-existence of these two disease lead to diagnostic dielemma among the clinicians. Overlapping clinical manifestations lead to delay in diagnosis. We report a case of acinic cell carcinoma -papillary cystic variant of the salivary gland and extra pulmonary tuberculosis in a young female. We emphasize the importance of the awareness of the co-existence of these two diseases and the role of fine needle aspiration cytology in the initial diagnosis.

This paper discusses the benefits of five phase technology for domestic wind turbine direct driven BLDC generators. The performances of five phase Radial Flux Permanent Magnet BLDC Generator (RFPMG) is discussed. Multi-phase technology harnesses some important benefits such as improved fault tolerance, reliability, reduced voltage and torque ripple. This paper also discusses the design of five phase RFPMG which was optimized to use in areas where wind speed is less. Finite element analysis and Matlab / Simulink are used in the investigations. Test results are also presented in this paper.

Sclerosing Peritonitis (SP) is characterized by fibrous thickening and adhesions of the peritoneum and it is encountered frequently in association with peritoneal dialysis, practolol and anticonvulsant therapy. Rarely does it present as a gynaecological complication, most commonly in conjunction with luteinized thecoma of ovary. Very rarely has sclerosing peritonitis been reported to occur with ovarian cystic teratoma and a luteinized variant of adult granulosa cell tumour, among which only one case has been reported in the English literature. An 18-year-female presented with a history of lower abdominal pain, of one month’s duration. At surgery, an ovarian mass was noted, along with adhesion of bowel loops which were enclosed within a diffusely thickened peritoneal membrane, forming a cocoon. Adhesions were seen in bilateral paracolic gutter and infracolic omentum, which were suggestive of metastatic deposits. Histopathology of ovarian lesion was interpreted as a juvenile granulosa cell tumour. The peritoneal process revealed sclerosing peritonitis. We emphasize this rare association of sclerosing peritonitis with juvenile granulosa cell tumour and that the peritoneal process of sclerosing peritonitis in a juvenile granulosa cell tumour should not lead to over staging of an ovarian tumour.

This paper presents the performance of three phase induction motor when magnetic wedges of different permeability are inserted in stator slots. Open slots produces variable reluctance path to the air gap flux and it reduces the output power of the machine and hence efficiency. Performance of motor without wedge and with different magnetic slot wedges i.e. cast iron, Magnoval® having different relative permeability are investigated using FEA-analysis, and the results shows that higher relative permeability materials reduces the output performance of the motor. This also validate the use of magnetic wedges of low permeability is reasonable with improved performance.

Sebaceous carcinoma (SC) is a highly aggressive malignant adnexal tumor of sebaceous gland origin, accounting for less than 1% of cutaneous. Extraocular sebaceous carcinomas are more aggressive than their ocular counterpart with a predilection for the skin of head and neck, trunk, salivary glands and extremities in decreasing order of frequency. Rippled effect literally means "gradually spreading effect". In histopathology it describes the unique arrangement of tumor cells in palisading pattern. The tumors in which rippled effect has been reported include adnexal tumors like trichoblastoma, trichomatricoma, trichoblastoma with sebaceous differentiation, trichoblastoma with apocrine differentiation, sebaceoma, basal cell carcinoma, fibrohistiocytic tumors, mesenchymal tumors and melanocytic tumors. We report the first case of extra ocular sebaceous carcinoma with rippled effect with emphasis on the fact that differentiation from other tumors demonstrating rippled effect is important in view of different treatment protocols.

The present study is carried out to study the damage observed at entrance and exit of the hole during drilling and surface quality of drilled hole on newly developed natural hybrid composites. Hybrid composite samples are prepared by using vinyl ester resin and three types of reinforcements namely, randomly oriented vetiveria zizanioides, woven jute and woven glass. The natural fibers are pre-treated with alkali and furnace heating in order to improve its surface properties. Three samples are developed by varying the composition of fibers in each one. Machinability study is done by drilling a series of 28 holes based on D-optimal design. Three output responses namely, damage factor at entrance and at exit and surface roughness are measured and optimized with an objective of minimizing the damages. Confirmatory runs are conducted and the responses are measured. The results are validated by calculating the average percentage of error between the model and confirmatory runs. The error was found to be minimal and hence the optimization is highly satisfactory.

Thrombotic occlusion is a potentially fatal complication of heart valve replacement surgery. The purpose of this report is to present our experience in the treatment of this group of patients, with emphasis on valve debridement as an effective surgical cure.Of 299 operative survivors undergoing valve replacement with Sorin Carbocast tilting disc prostheses at our institution 270 could be followed up: 18 of them (6.7%) developed thrombosis within 26 months. All thrombotic blocks occurred in the mitral position. Anticoagulation was sub-therapeutic in 13 patients. Clinically, the patients presented with dyspnea, congestive cardiac failure, acute pulmonary edema or chest pain. Prosthetic valve closure sounds were absent or muffled in all patients and new murmurs developed in two. The average duration of symptoms was 3.0 days (range eight hours to 15 days). Diagnosis was made on physical examination alone, and echocardiographic confirmation was possible in 11 patients. Ten underwent emergency surgery, all by valve debridement with retention of the prosthesis.Of the operated patients, eight survived with restoration of prosthetic valve function. Complications including hypoxic encephalopathy and acute renal failure occurred in two patients (20%). One death occurred 13 months later due to renal failure. At a follow up of 18 to 32 months (mean 21.3 months), seven patients are alive and well, and in NYHA functional class I or II. One patient developed a recurrent prosthetic valve thrombotic occlusion, and underwent successful surgical debridement for a second time. Thrombolysis was attempted in two cases with early success, but recurrent prosthetic valve thrombosis occurred.The incidence of PVT was 6.7% in 270 patients with Sorin tilting disc valves implanted and followed up for 26 months. Though thrombolysis is initially successful, recurrent valve thrombosis is a risk. Emergency surgical treatment allowed 70% mid term survival after valve debridement alone. Adequate anticoagulation and regular medical follow up postoperatively need to be strongly emphasized.

The present work is carried out to investigate the delamination defects and surface roughness during drilling on newly developed biodegradable hybrid composite laminates. The natural hybrid composite consists of Natural vetiveria zizaniodes (vetiver) and synthetic glass are used as reinforcements in vinyl ester resin to form four composite specimens based on varying the fiber compositions in each specimen while the resin content is kept as a constant. The specimens are subjected to drilling operations during which machining parameters like speed, feed rate, tool point angle and work sample are varied between four levels to form 4 4 D-optimal factorial design. After 28 runs the delamination factor at the entrance and exit of hole and machined sub- surface roughness are measured as responses. The responses are analyzed using response surface method and non-linear regression equations are developed. Optimization on the data resulted in selection of best level of speed, feed and tool angle for the selected samples. Confirmatory runs have been conducted and the responses are measured. Average error between the model and confirmatory run was found minimal and hence the optimization was found to be satisfactory.