Algorithm to select the voltage class for the gas field electricity supply system

The current algorithms and mathematical models to select the voltage class based on the theory of experimental planning are developed for industrial enterprises (overhead lines with a length of up to 10 km, a power of up to 20 MV, a radial arrangement with a transformation at the end of the line). They do not consider the features of gas fields (overhead lines with a length of up to 20 km and a capacity of 1 MV with a projected growth of up to 10 MV, a transmission network with one pass-through trunk line with distributed transformation along the line). Currently, to develop a mathematical model, the following factors are considered: the average length of the power line and the total load of an enterprise. The proposed models do not allow us to quantify the dynamics of the gas fields power supply system considering the multiple growth of the electrical load in each period of the life cycle. The purpose of this study is to develop a model to solve this problem. An extreme experiment has been carried out during the research. The following input data are set: the average length of the power line; the number of gas clusters; the growth rate of the electric load. The response function is the voltage class that is optimal for the minimum discounted cost. The authors suggest the regression model. In this model the “total load” factor is split into two components, they are gas clusters and growth rate of electric loads. The algorithm to select the optimal voltage class of a distribution grid is proposed. The dynamic experiment is carried out and the growth rate of electric loads in the regressive model is being changed while other factors are being unchanged. As a result, the optimal minimum of the discounted costs of the voltage class for each period of the field life cycle is obtained. The algorithm is implemented in “PRON” software. With the help of “PRON” software, the distribution grids of several operating gas fields in Western Siberia have been investigated. The optimal voltage class of a distribution grid of gas fields is 20 kV. The reliability of the results is verified by reference models of calculating discounted costs.

Cost-efficient pre-commercial thinning: effects of method and season of early cleaning

This study’s aim was to identify how the application season and the method of early cleaning (EC), the first stage of multistage pre-commercial thinning (PCT), affected the time consumption in EC and in the subsequent second PCT operation. The worktime in EC was recorded in the spring, summer, and autumn in 22 sites, which were either totally cleaned or point cleaned. Later, these sites were measured at the time of the second PCT. Time consumption was estimated in PCT, based on the removal of the sites. The time consumption in EC was 5.3 productive work hours (pwh) ha, 7.3 pwh ha, and 6.2 pwh ha respectively in the spring, summer, and autumn. EC in the spring instead of the summer saved 27–30% of working time, depending on the cleaning method. Point cleaning was 0.8 pwh ha quicker than total cleaning, but the difference was statistically insignificant. The second stage, PCT, was 1 pwh ha slower to conduct in sites which had been early cleaned in the spring instead of the summer. However, at the entire management program level, EC applied in the spring or autumn instead of the summer saved 11% or 5% respectively of the total discounted costs (3% interest rate) of multistage pre-commercial thinning. Today, the commonest time to conduct EC is in the summer, which was the most expensive of the analyzed management alternatives here. We can expect savings in juvenile stand management in forestry throughout boreal conifer forests by rethinking the seasonal workforce allocation.–1–1–1–1–1

Cost-Effectiveness of Surveillance Scanning Strategies after Curative Treatment of Non–Small-Cell Lung Cancer

Background After curative treatment of primary non–small-cell lung cancer (NSCLC), patients undergo intensive surveillance with the aim to detect recurrences from the primary tumor or metachronous second primary lung cancer as early as possible and improve overall survival. However, the benefit of surveillance is debated. Available evidence is of low quality and conflicting. Microsimulation modeling facilitates the exploration of the impact of different surveillance strategies and provides insight into the cost-effectiveness of surveillance. Methods A microsimulation model was used to simulate a range of computed tomography (CT)–based surveillance schedules, differing in the frequency and duration of CT surveillance. The impact on survival, quality-adjusted life-years, costs, and cost-effectiveness of each schedule was assessed. Results Ten of 108 strategies formed the cost-effectiveness frontier; that is, these were the strategies with the optimal cost-health benefit balance. Per person, the discounted QALYs of these strategies varied between 5.72 and 5.81 years, and discounted costs varied between €9892 and €19,259. Below a willingness-to-pay threshold of €50,000/QALY, no scanning is the preferred option. For a willingness-to-pay threshold of €80,000/QALY, surveillance scanning every 2 y starting 1 y after curative treatment becomes the best option, with €11,860 discounted costs and 5.76 discounted QALYs per person. The European Society for Medical Oncology guideline strategy was more expensive and less effective than several other strategies. Conclusion Model simulations suggest that limited CT surveillance scanning after the treatment of primary NSCLC is cost-effective, but the incremental health-benefit remains marginal. However, model simulations do suggest that the guideline strategy is not cost-effective.

Cost-Effectiveness of a 12-Month Fixed Duration of Venetoclax in Combination with Obinutuzumab Versus Chemoimmunotherapy and Other Novel Combinations in First-Line Chronic Lymphocytic Leukemia in Canada

OBJECTIVES: To estimate the cost-effectiveness of venetoclax + obinutuzumab (GAZYVA®, G), (VEN+G) in the treatment of first-line (1L) chronic lymphocytic leukemia (CLL) from a Canadian health care system cost perspective. METHODS: A three-state partitioned-survival model was used to extrapolate progression-free survival (PFS) and overall survival (OS) over a 10-year time horizon. Cost-effectiveness was estimated comparing 12-month fixed duration of VEN+G versus (vs) G + Chlorambucil (GClb) based on the CLL14 clinical trial (NCT02242942). Other comparators included Bendamustine + rituximab (BR), Chlorambucil + rituximab (Clb+R), Ibrutinib (Ibr), Acalabrutinib (Acala) and Acalabrutinib + GAZYVA (Acala+G). VEN+G was also compared to the combination of fludarabine, cyclophosphamide and rituximab (FCR) in the overall 1L CLL population which included unfit and fit patients. Relative efficacy of VEN+G vs other comparators was estimated using a network meta-analysis. Health state utilities and adverse event disutilities were derived from a systematic literature review and other published sources. Costs included CLL treatment, routine care and monitoring, adverse events, disease progression costs, subsequent treatment costs, and end of life care. Uncertainty was assessed using an underlying probabilistic model (probabilistic analysis of uncertainty generated from 5,000 iterations), through deterministic sensitivity analyses (i.e., one-way sensitivity analyses (OWSA)), and through a series of alternative scenario analyses. RESULTS: For the overall unfit 1L CLL patient population, the probabilistic total discounted costs incurred over a 10-year time horizon were as follows: $217,727 for VEN+G vs $312,287 for GClb, $399,219 for BR, $380,713 for Clb+R, $736,017 for Ibr, $868,797 for Acala and $916,139 for Acala+G. The probabilistic total discounted quality adjusted life years (QALYs) were 4.964 for VEN+G vs 4.750, 4.550, 4.422, 4.709, 5.269, and 5.359, respectively for the comparators. For the overall 1L CLL patient population, the probabilistic total discounted costs were $219,651 for VEN+G vs $312,570 for GClb, $342,195 for FCR, $397,262 for BR, $380,551 for Clb+R, $757,129 for Ibr, $868,388 for Acala, and $916,798 for Acala+G. The probabilistic total discounted QALYs were 5.888 for VEN+G vs 5.519, 5.067, 5.198, 5.073, 5.597, 6.259 and 6.380, respectively for the comparators. VEN+G was found to be less costly and more efficacious (i.e., dominant) compared to GClb, BR, Clb+R, Ibr and FCR. As a result, incremental cost utility ratios (ICERs) were not calculated for these comparators. Acala and Acala+G resulted in ICERs ranging from $1.4-$2.1 million per QALY gained relative to VEN+G, which is not cost-effective. Based on the probabilistic model and 5,000 simulations, VEN+G was found to be at least 97% cost-effective across all decision maker willingness-to-pay thresholds. The results from the deterministic model were found to be similar to the probabilistic model. Using the deterministic model, and in comparison to the most commonly prescribed treatment for 1L CLL in Canada (i.e., Ibr), the OWSA comparing VEN+G to Ibr found that the most influential variables in the model were the PFS and OS hazard ratios for Ibr and the utility values for PFS and post-progression survival. CONCLUSION: VEN+G is an effective novel fixed duration treatment option which leads to deep and durable responses for the treatment of patients with unfit 1L CLL and provides excellent value-for-money compared with existing chemoimmunotherapy and treat to progression novel combinations. Disclosures Chatterjee: Pharmerit: Current Employment. Van de Wetering:Pharmerit: Current Employment. Goeree:AbbVie Inc.: Consultancy. Desbois:AbbVie Inc.: Current Employment, Current equity holder in publicly-traded company. Manzi:AbbVie Inc.: Current Employment, Current equity holder in publicly-traded company. Manzoor:AbbVie: Current equity holder in publicly-traded company. Owen:AbbVie, F. Hoffmann-La Roche, Janssen, Astrazeneca, Merck, Servier, Novartis, Teva: Honoraria. Sail:AbbVie Inc.: Current Employment, Current equity holder in publicly-traded company.

Cost-Effectiveness of a 12-Month Fixed Duration of Venetoclax in Combination with Obinutuzumab in First-Line Chronic Lymphocytic Leukemia in the United States

INTRODUCTION: Historically chemoimmunotherapy has been the standard of care in the treatment of first-line (1L) chronic lymphocytic leukemia (CLL). More recently several effective oral targeted agents, such as ibrutinib-based regimens, have provided effective chemotherapy-free treatment options in CLL. However, these therapies require continuous treatment until disease progression. Recently FDA approved (May 2019), venetoclax plus obinutuzumab (VenG) is a highly effective chemotherapy-free therapy that is used over a 12-month fixed treatment duration (Fischer et al, N Eng J Med 2019). The objective of this study is to estimate the cost-effectiveness of VenG in the treatment of 1L CLL from a US-payer perspective. METHODS: A three-state partitioned-survival model was used to extrapolate progression-free survival and overall survival over a lifetime horizon (20 years). Cost-effectiveness was estimated by comparing a 12-month fixed duration of VenG versus (vs.) chlorambucil-obinutuzumab (ClbG) based on the CLL14 clinical trial (NCT02242942). Other comparators included treat-to-progression therapies, such as ibrutinib (IBR), IBR + rituximab (IR), and IBR + G (IG), and a 6-month course of bendamustine + rituximab (BR). Using a network meta-analysis, the relative efficacy of VenG and ClbG vs. other selected comparators was estimated. Health state utilities and adverse event (AE) disutilities were derived from a systematic literature review and published health-technology assessment reports. To generate total quality-adjusted life years (QALYs), these health state utilities and AE disutilities were applied to the relative efficacy data. US-specific costs included those for CLL treatment, routine care and monitoring, AEs, disease progression (including subsequent treatment), and end-of-life care. Cost-effectiveness results are presented in terms of incremental cost per QALY. A new treatment that is both lower in total cost and more efficacious (in QALYs) vs. identified comparator treatments is described as being "dominant". Uncertainty in the model was tested through deterministic, probabilistic, and scenario analyses. RESULTS: The benefits in the cost-effectiveness model (CEM) were measured in terms of total discounted QALYs which were 6.47 for VenG, 6.12 for ClbG, 6.11 for IBR, 6.08 for IR, 6.41 for IG, and 5.98 for BR. The total discounted costs incurred by VenG and ClbG were $322,613 and $847,571, respectively. IBR-based treat-to-progression regimens incurred total discounted costs of $1,485,368 for IBR, $1,447,010 for IR, and $1,988,706 for IG. BR incurred total discounted costs of $808,756. Compared to these regimens, VenG is less costly (incremental cost ranges between: -$1,666,093 to -$486,143). The incremental discounted QALYs of VenG was: 0.36 vs. GC, 0.49 vs. BR, 0.37 vs. IBR, 0.06 vs. IG, and 0.39 vs. IR. Thus, VenG with a 12-month fixed duration, has lower total costs and is more efficacious ("dominant") over all comparators in the CEM. The probabilistic sensitivity analysis results were in line with the deterministic results. Sensitivity analysis indicated the post-progression survival utility was the most influential parameter on the model outcomes. As the CLL14 trial data matures, these cost-effectiveness estimates may change and additional scenarios for post-progression survival for VenG will be explored. Updated results will be presented. CONCLUSIONS: VenG is projected to be cost-effective vs. ClbG within accepted US cost-effectiveness thresholds. Compared with BR and IBR-based treat-to-progression regimens (IBR, IR, and IG), a 12-month fixed-duration treatment option with VenG seems cost saving and more efficacious based on the CEM. Taken together, VenG appears to be a cost-effective standard therapy for 1L CLL patients. Disclosures Davids: AbbVie, Acerta Pharma, Adaptive, Biotechnologies, Astra-Zeneca, Genentech, Gilead Sciences, Janssen, Pharmacyclics, TG therapeutics: Membership on an entity's Board of Directors or advisory committees; Research to Practice: Honoraria; AbbVie, Astra-Zeneca, Genentech, Janssen, MEI, Pharmacyclics, Syros Pharmaceuticals, Verastem: Consultancy; Acerta Pharma, Ascentage Pharma, Genentech, MEI pharma, Pharmacyclics, Surface Oncology, TG Therapeutics, Verastem: Research Funding. Ravelo:Genentech: Employment, Equity Ownership. Shapouri:Roche: Equity Ownership; Genentech, Inc.: Employment. Manzoor:AbbVie: Employment, Other: and may hold stock or stock options. Sail:AbbVie: Employment, Other: and may hold stock or stock options. Van de Wetering:AbbVie: Consultancy. Hallek:Roche, Gilead Sciences, Inc., Mundipharma, Janssen, Celgene, Pharmacyclics, AbbVie: Honoraria, Research Funding, Speakers Bureau.

ECONOMIC CORRECTION OF CURRENT DENSITIES IN THE WIRES OF THE EXISTING OVERHEAD LINES OF 110-220 KV

In this article, we present the methods used to date, the choice of the cross-sections of the wires of overhead transmission lines, taking into account not only the losses from the load currents, but also the corona losses and linear insulation of overhead transmission lines. The method of economic optimization of electrical loads and current density in operating air lines is considered, where the target functions are the specific discounted costs for transmission of 1 kW. h of electric power.