28 research outputs found

    A simplified analytical approach for optimal planning of distributed generation in electrical distribution networks

    Get PDF
    DG-integrated distribution system planning is an imperative issue since the installing of distributed generations (DGs) has many effects on the network operation characteristics, which might cause significant impacts on the system performance. One of the most important characteristics that mostly varies because of the installation of DG units is the power losses. The parameters affecting the value of the power losses are number, location, capacity, and power factor of the DG units. In this paper, a new analytical approach is proposed for optimally installing DGs to minimize power loss in distribution networks. Different parameters of DG are considered and evaluated in order to achieve a high loss reduction in the electrical distribution networks. The algorithm of the proposed approach has been implemented using MATLAB software and has been tested and investigated on 12-bus, 33-bus, and 69-bus IEEE distribution test systems. The results show that the proposed approach can provide an accurate solution via simple algorithm without using exhaustive process of power flow computations

    Contemporary results from the PelvEx collaborative: improvements in surgical outcomes for locally advanced and recurrent rectal cancer

    Get PDF
    Aim: The PelvEx Collaborative collates global data on outcomes following exenterative surgery for locally advanced and locally recurrent rectal cancer (LARC and LRRC, respectively). The aim of this study is to report contemporary data from within the collaborative and benchmark it against previous PelvEx publications. Method: Anonymized data from 45 units that performed pelvic exenteration for LARC or LRRC between 2017 and 2021 were reviewed. The primary endpoints were surgical outcomes, including resection margin status, radicality of surgery, rates of reconstruction and associated morbidity and/or mortality. Results: Of 2186 patients who underwent an exenteration for either LARC or LRRC, 1386 (63.4%) had LARC and 800 (36.6%) had LRRC. The proportion of males to females was 1232:954. Median age was 62 years (interquartile range 52-71 years) compared with a median age of 63 in both historical LARC and LRRC cohorts. Compared with the original reported PelvEx data (2004-2014), there has been an increase in negative margin (R0) rates from 79.8% to 84.8% and from 55.4% to 71.7% in the LARC and LRRC cohorts, respectively. Bone resection and flap reconstruction rates have increased accordingly in both cohorts (8.2%-19.6% and 22.6%-32% for LARC and 20.3%-41.9% and 17.4%-32.1% in LRRC, respectively). Despite this, major morbidity has not increased. Conclusion: In the modern era, patients undergoing pelvic exenteration for advanced rectal cancer are undergoing more radical surgery and are more likely to achieve a negative resection margin (R0) with no increase in major morbidity

    Contemporary Management of Locally Advanced and Recurrent Rectal Cancer: Views from the PelvEx Collaborative

    Get PDF
    Pelvic exenteration is a complex operation performed for locally advanced and recurrent pelvic cancers. The goal of surgery is to achieve clear margins, therefore identifying adjacent or involved organs, bone, muscle, nerves and/or vascular structures that may need resection. While these extensive resections are potentially curative, they can be associated with substantial morbidity. Recently, there has been a move to centralize care to specialized units, as this facilitates better multi-disciplinary care input. Advancements in pelvic oncology and surgical innovation have redefined the boundaries of pelvic exenterative surgery. Combined with improved neoadjuvant therapies, advances in diagnostics, and better reconstructive techniques have provided quicker recovery and better quality of life outcomes, with improved survival This article provides highlights of the current management of advanced pelvic cancers in terms of surgical strategy and potential future developments

    Effect of Integrating Photovoltaic Systems on Electrical Network Losses Considering Load Variation

    No full text
    Planning of Distributed Generation (DG) units in the power distribution networks is an important issue, one of the most important considerations that is directly affected by installing DG units is the power losses. Improper allocation of DG units to the grid can lead to a noticeable increase in the power losses. Moreover, the load variation is considered as critical matter when studying the optimal scenario that minimizes the power losses in the network. The aim of this paper is to investigate the effect of integrating photovoltaic (PV) units on the distribution network losses considering load variation. The optimal parameters of the DG units were calculated for the various load demands in the system. Moreover, a comparison between the power losses in the case of varying DG penetration level with constant penetration level of DG has been presented. All of the results in this paper have been tested, simulated and investigated on a modified 33-bus IEEE test system using Matlab program
    corecore