On the Breeding of “CSR18${\times}$CSR19”- A Robust Bivoltine Hybrid of Silkworm, Bombyx mori L. for the Tropics

Kumar, N.Suresh,Basavaraja, H.K.,Kumar, C.M.Kishor,Reddy, N.Mal,Datta, R.K. Korean Society of Sericultural Science 2002 International Journal of Industrial Entomology Vol.5 No.2

Earlier breeding experiments undertaken at Central Sericultural Research and Training Institute, Mysore, India since a decade had resulted in the development of many productive and qualitatively superior bivoltine hybrids. However, the hot climatic conditions of tropics prevailing particularly in summer are not conducive to rear these high yielding bivoltine hybrids. This has necessitated breeding of compatible bivoltine hybrids for year-round rearing. Accordingly, the Japanese hybrid, B2Ol ${\times}$ BCS12 which was found to be tolerant to high temperature was used as breeding resource material. Following hybridization and selection rearing of silkworms was taken up in SERICATRON (Environmental chamber with precise and automatic control facilities for uniform maintenance of temperature and humidity) at high temperature of $36{\times}1^{\circ}C$ and 85${\times}$5% RH in fifth instar and the control batches at $25{\times}1^{\circ}C$ and 65{\times}$5% RH. Directional selection was resorted to the batches reared at 36$\pm$1$^{\circ}C$ till F$_{5}$ keeping pupation rate as important selection criteria. From $F_{2}% onwards the experiment was modified in such a way as to conduct normal rearing every alternate generation to regain the lost vitality due to continuous exposure to high temperature and high humidity stress. At $F_{2}$ , Oval and dumb-bell cocoons were separated out and designated as CSR18 and CSR19, respectively. By utilizing these lines at $F_{12}$, the hybrid CSR18$\times$CSR19 was prepared and studied for the thermotolerance by subjecting to stress condition at high temperature of 36$\pm$1$^{\circ}C$ and 85$\pm$5% RH in fifth instar and the control batches at $25{\times}1^{\circ}C$ and 65${\times}$5% RH. The better performance of CSR18${\times}$CSR19 (survival > 88%) at $36{\times}1^{\circ}C$ clearly indicates the general superiority of CSR18${\times}$CSR19 with regard to high temperature tolerance over the productive hybrids and CSR18$\times$CSR19 can perform well in varied agro-climatic conditions of the tropics with optimum qualitative and quantitative characteristics.s.

NUMERICAL AND EXPERIMENTAL INVESTIGATION OF LUBRICATING OIL FLOW IN A GEROTOR PUMP

M. SURESH KUMAR,K. MANONMANI 한국자동차공학회 2011 International journal of automotive technology Vol.12 No.6

Gerotor pumps are widely used in the automotive industry for engine oil lubrication, due to their high volumetric efficiency and smooth pumping action. In many cases, the lubricating oil from the sump is mixed with contaminants, such as dust and tiny solid particles, or becomes thickened, due to aging. These problems will lead to critical situations, such as increased noise, enhanced wear and erosion, and poor lubrication of the engine. These critical situation were studied by conducting a detailed CFD integrated investigation on a gerotor pump’s performance at different operating conditions in three phases, and the results are presented in this paper. In first phase, a CFD model of a gerotor pump was developed with a dynamic mesh for the rotary movement of both the inner and outer rotors. The effects on pump flow rate of important parameters, such as rotor speed, fluid viscosity and number of ports, were simulated using non-contaminated oil at room temperature and an elevated temperature of 140oC. The relationship between flow rate and pressure at different rotor speeds was predicted and validated with test data for further parametric study. The pressure ripples at different time steps were measured at different angular positions of the rotors to examine the model accuracy. It was found that the flow rate increased and pressure pulsation, as well as flow recirculation, was reduced when ports were added to the cover plate. A suction pipe with a strainer was added for the second phase to capture the undesired changes in flow behavior, such as cavitation, which is caused by negative suction at the inlet region of pump. A suitable size for the inlet suction pipe for this pump was chosen after performing tests to characterize the flow behavior with single and double ports. Next, the relationship between pressure drop and strainer porosity was determined using different porosity values for the strainers. In the final phase, oil with different concentrations of solids was simulated to measure the effect of solid particles on flow rates and pressure losses. It was observed that the intensity of the recirculation was reduced at the suction end at the higher concentration of 0.04%, due to particle inertial effects. It was also found that particle size distribution affected the overall efficiency and pressure head of the pump.

Performance study of various discontinuous PWM strategies for multilevel inverters using generalized space vector algorithm

Suresh Kumar, A.,Sri Gowri, K.,Vijaya Kumar, M. The Korean Institute of Power Electronics 2020 JOURNAL OF POWER ELECTRONICS Vol.20 No.1

The space vector (SV) pulse-width modulation (PWM) approach is extensively preferred in the control of multilevel inverters (MLI). In this paper, the implementation of various advanced discontinuous pulse-width modulation (ADPWM) strategies using a generalized space vector algorithm is presented. The ADPWM MIN, ADPWM MAX, and ADPWM 0~ADPWM 3, strategies are developed using a combination of advanced switching sequences 1012-2721 and 0121-7212. The output performance in terms of voltage THD, current THD, and reduction of common mode voltage (CMV) of a three-level inverter-fed induction motor for different ADPWM strategies is investigated initially through MATLAB simulation and comparison of the obtained results is presented. It can be observed that the ADPWM 1 strategy with the 0121-7212 switching sequence offered the best performance in terms of the voltage and current THD at the modulation range of 47.5 Hz to 50 Hz. In addition, it is validated experimentally. Experimental work is done on a V/f-controlled three-level inverter-fed induction motor with the help of dSPACE. To validate the study, experimental results of the line voltage, stator current, and CMV waveforms for the ADPWM 1 (optimal performance PWM strategy) are presented in comparison with the 0127 sequence at fundamental frequencies of 49 Hz and 30 Hz.

Fluorescence quenching of 5-methyl-3-phenyl-2-[s-oxadiazol-2'-thione- 5'-yl]indole by CCl4 and aniline in different solvents

Kumar, H M Suresh,Kunabenchi, R S,Biradar, J S,Math, N N,Kadadevaramath, J S 한국광과학회 2003 Journal of Photosciences Vol.10 No.3

New Generalized SVPWM Algorithm for Multilevel Inverters

Kumar, A. Suresh,Gowri, K. Sri,Kumar, M. Vijay The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.4

In this paper a new generalized space vector pulse width modulation scheme is proposed based on the principle of reverse mapping to drive the switches of multilevel inverters. This projected scheme is developed based on the middle vector of the subhexagon which holds the tip of the reference vector, which plays a major role in mapping the reference vector. A new approach is offered to produce middle vector of the subhexagon which holds tip of the reference vector in the multilevel space vector plane. By using middle vector of the subhexagon, reference vector is linked towards the inner two level sub-hexagon. Then switching vectors, switching sequence and dwell times corresponding to a particular sector of a two-level inverter are determined. After that, by using the two level stage findings, the switching vectors related to exact position of the reference vector are directly generated based on principle of the reverse mapping approach and do not need to be found at n level stage. In the reverse mapping principle, the middle vector of subhexagon is added to the formerly found two level switching vectors. The proposed generalized algorithm is efficient and it can be applied to an inverter of any level. In this paper, the proposed scheme is explained for a five-level inverter and the performance is analyzed for five level and three level inverters through MATLAB. The simulation results are validated by implementing the propose scheme on a V/f controlled three-level inverter fed induction motor using dSPACE control desk.

Fluorescence quenching of 5-methyl-3-phenyl-2-[s-oxadiazol-2'-thione-5'-yl] indole by $CCl_4$ and aniline in different solvents

H M, Suresh-Kumar,R S, Kunabenchi,J S, Biradar,N N, Math,J S, Kadadevaramath Korean Society of Photoscience 2003 Journal of Photosciences Vol.10 No.3

The fluorescence quenching of 5-methyl-3-phenyl-2-[s-oxadiazol-2'-thionen5'-yl] indole by carbon tetrachloride ($CCl_4$) and aniline in different solvents viz., dioxane, benzene, toluene, methanol, propanol has been carried out at room temperature to understand the role of quenching mechanisms. The Stern-Volmer plots have been found to be linear. As probability of quenching per encounter 'p' is less than unity, and the activation energy for quenching 'E$_{a}$' is greater than the activation energy of diffusion 'E$_{d}$', it is inferred that the fluorescence of quenching mechanism is not due to material diffusion alone.e.e.

Design and simulation of resonance based DC current sensor

Santhosh Kumar, B.V.M.P.,Suresh, K.,Varun Kumar, U.,Uma, G.,Umapathy, M. Techno-Press 2010 Interaction and multiscale mechanics Vol.3 No.3

A novel resonance based proximity DC current sensor is proposed. The sensor consists of a piezo sensed and actuated cantilever beam with a permanent magnet mounted at its free end. When the sensor is placed in proximity to a wire carrying DC current, resonant frequency of the beam changes with change in current. This change in resonant frequency is used to determine the current through the wire. The structure is simulated in micro and meso scale using COMSOL Multi physics software and the sensor is found to be linear with good sensitivity.

New Generalized SVPWM Algorithm for Multilevel Inverters

A. Suresh Kumar,K. Sri Gowri,M. Vijay Kumar 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.4

In this paper a new generalized space vector pulse width modulation scheme is proposed based on the principle of reverse mapping to drive the switches of multilevel inverters. This projected scheme is developed based on the middle vector of the subhexagon which holds the tip of the reference vector, which plays a major role in mapping the reference vector. A new approach is offered to produce middle vector of the subhexagon which holds tip of the reference vector in the multilevel space vector plane. By using middle vector of the subhexagon, reference vector is linked towards the inner two level sub-hexagon. Then switching vectors, switching sequence and dwell times corresponding to a particular sector of a two-level inverter are determined. After that, by using the two level stage findings, the switching vectors related to exact position of the reference vector are directly generated based on principle of the reverse mapping approach and do not need to be found at n level stage. In the reverse mapping principle, the middle vector of subhexagon is added to the formerly found two level switching vectors. The proposed generalized algorithm is efficient and it can be applied to an inverter of any level. In this paper, the proposed scheme is explained for a five-level inverter and the performance is analyzed for five level and three level inverters through MATLAB. The simulation results are validated by implementing the propose scheme on a V/f controlled three-level inverter fed induction motor using dSPACE control desk.

On the Breeding of "CSR18×CSR19" - A Robust Bivoltine Hybrid of Silkworm, Bombyx mori L. for the Tropics

( N. Suresh Kumar ),( H. K. Basavaraja ),( C. M. Kishor Kumar ),( N. Mal Reddy ),( R. K. Datta ) 한국잠사학회 2002 International Journal of Industrial Entomology Vol.5 No.2

Fuzzy Location Algorithm for Cross-Country and Evolving Faults in EHV Transmission Line

A. Naresh Kumar,M. Chakravarthy,M. Suresh Kumar,M. Nagaraju,M. Ramesha,Bharathi Gururaj,Elemasetty Uday Kiran 한국지능시스템학회 2023 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.23 No.2

Fault protection is an important issue as it adversely affects the performance of conventional relays, particularly for cross-country and evolving faults in transmission lines. In this paper, a novel fault location algorithm for cross-country and evolving faults in extra high voltage transmission (EHVT) line using the fuzzy expert system (FES) is presented. The algorithm is based on the impedance values of relaying terminal fundamental component. In addition, the proposed FES is independent of communication links. It was designed using input variables via the IF-THEN rules and developed with the fuzzy MAMDANI structure. A triangular membership function was used to estimate the degree of inputs. MATLAB software was used to evaluate the error in the fault location for a 100-km, 400-kV, 50-Hz EHVT line. The FES algorithm yielded precise values. The test results were independent of the fault inception time, location, and type. The experimental results illustrate that the FES performed better than the other algorithms.