ANN Control for Improved Performance of Wind Energy System Connected to Grid

This paper proposes the novel control strat- egy to improve the power quality injection of wind energy system using Doubly Fed Induction Generator (DFIG) into the grid by implementing artificial neu- ral network. The torque ripple produced in DFIG due to loading by grid tied inverter, which leads to poor power quality injection into the system. Also, these ripples transferred by DC link and causes heating losses and generator phase current distortion. There- fore, this paper modelled ANN based control scheme to reduce the torque ripple content and restrict the trans- fer of ripple by DC link to improve the outcome of wind energy system while operating in variable conditions. The DFIG system under studied are modelled and simulated in MATLAB SIMULINK to verify the improvement using proposed control strategy. The recent control technique is also simulated for reflecting the effectiveness in the proposed control method. The outcomes obtained are studied and analysed with the existing control scheme to highlight the improvement obtained by proposed control

Understanding the Impact of Male Circumcision Interventions on the Spread of HIV in Southern Africa

BACKGROUND: Three randomised controlled trials have clearly shown that circumcision of adult men reduces the chance that they acquire HIV infection. However, the potential impact of circumcision programmes--either alone or in combination with other established approaches--is not known and no further field trials are planned. We have used a mathematical model, parameterised using existing trial findings, to understand and predict the impact of circumcision programmes at the population level. FINDINGS: Our results indicate that circumcision will lead to reductions in incidence for women and uncircumcised men, as well as those circumcised, but that even the most effective intervention is unlikely to completely stem the spread of the virus. Without additional interventions, HIV incidence could eventually be reduced by 25-35%, depending on the level of coverage achieved and whether onward transmission from circumcised men is also reduced. However, circumcision interventions can act synergistically with other types of prevention programmes, and if efforts to change behaviour are increased in parallel with the scale-up of circumcision services, then dramatic reductions in HIV incidence could be achieved. In the long-term, this could lead to reduced AIDS deaths and less need for anti-retroviral therapy. Any increases in risk behaviours following circumcision, i.e. 'risk compensation', could offset some of the potential benefit of the intervention, especially for women, but only very large increases would lead to more infections overall. CONCLUSIONS: Circumcision will not be the silver bullet to prevent HIV transmission, but interventions could help to substantially protect men and women from infection, especially in combination with other approaches

Natural orifice transluminal endoscopic surgery (hybrid) cholecystectomy: The Dhillon technique

Introduction: This study presents a novel technique to perform cholecystectomy and assess its outcome and feasibility. Patients and Methods: This study presents the novel Dhillon technique and experience of hybrid natural orifice transluminal endoscopic surgery (NOTES) technique, that is, laparoscopic-assisted transvaginal cholecystectomy. We have evaluated the outcomes in terms of cosmesis, post-operative recovery and analgesic requirement. The study included 257 patients who underwent hybrid NOTES cholecystectomy at single tertiary hospital. The biographical data, surgical time, pain score on day 1 and 2, need of analgesia, intra- and post-operative complication and aesthetic assessment on day 7 were recorded. Results: Out of a total of 1100 cases of laparoscopic cholecystectomy 257 had hybrid NOTES cholecystectomy. Only two of these cases were converted to standard laparoscopic cholecystectomy. The mean operative time was 31.5 ± 5.1 (25–40) min. None of the patients had any complication or biliary leakage. The mean pain score on day 1 and 2 was 3.6 ± 0.4 (3–4) and 1.0 ± 0.06 (1–2), respectively. The mean paracetamol (analgesic) dose requirement was 6.1 ± 0.6 (4–6.9) g. The aesthetic score was excellent in all the cases. Conclusions: Using the present technique of hybrid NOTES is beneficial in terms of cosmetic results, lesser need of analgesic and shorter hospital stay

Preduodenal portal vein: A recipe for disaster during laparoscopic cholecystectomy

We had encountered a very rare congenital anomaly of a preduodenal portal vein while doing laparoscopic cholecystectomy. More significant in our case is that this preduodenal vein is hiding behind omental adhesions with the gallbladder. We want to raise awareness about this very rare anomaly. Recognition and knowledge of this anomaly will prevent the potential of a serious operative misadventure