Journal articles: 'CHP model'

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Wong-Kcomt, Jorge B. "The CHP Space: A Basic Model." Distributed Generation & Alternative Energy Journal 27, no. 3 (June 2012): 72–80. http://dx.doi.org/10.1080/21563306.2012.10531124.

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Wong-Kcomt, Jorge B. "The CHP Space: A Basic Model." Distributed Generation & Alternative Energy Journal 27, no. 4 (September 2012): 74–78. http://dx.doi.org/10.1080/21563306.2012.10554223.

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Mansour, Ahmed, Sherif Rashad, Kuniyasu Niizuma, Miki Fujimura, and Teiji Tominaga. "A novel model of cerebral hyperperfusion with blood-brain barrier breakdown, white matter injury, and cognitive dysfunction." Journal of Neurosurgery 133, no. 5 (November 2020): 1460–72. http://dx.doi.org/10.3171/2019.7.jns19212.

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OBJECTIVECerebral hyperperfusion (CHP) is associated with considerable morbidity. Its pathophysiology involves disruption of the blood-brain barrier (BBB) with subsequent events such as vasogenic brain edema and ischemic and/or hemorrhagic complications. Researchers are trying to mimic the condition of CHP; however, a proper animal model is still lacking. In this paper the authors report a novel surgically induced CHP model that mimics the reported pathophysiology of clinical CHP including BBB breakdown, white matter (WM) injury, inflammation, and cognitive impairment.METHODSMale Sprague-Dawley rats were subjected to unilateral common carotid artery (CCA) occlusion and contralateral CCA stenosis. Three days after the initial surgery, the stenosis of CCA was released to induce CHP. Cortical regional cerebral blood flow was measured using laser speckle flowmetry. BBB breakdown was assessed by Evans blue dye extravasation and matrix metalloproteinase–9 levels. WM injury was investigated with Luxol fast blue staining. Cognitive function was assessed using the Barnes circular maze. Other changes pertaining to inflammation were also assessed. Sham-operated animals were prepared and used as controls.RESULTSCerebral blood flow was significantly raised in the cerebral cortex after CHP induction. CHP induced BBB breakdown evident by Evans blue dye extravasation, and matrix metalloproteinase–9 was identified as a possible culprit. WM degeneration was evident in the corpus callosum and corpus striatum. Immunohistochemistry revealed macrophage activation and glial cell upregulation as an inflammatory response to CHP in the striatum and cerebral cortex. CHP also caused significant impairments in spatial learning and memory compared with the sham-operated animals.CONCLUSIONSThe authors report a novel CHP model in rats that represents the pathophysiology of CHP observed in various clinical scenarios. This model was produced without the use of pharmacological agents; therefore, it is ideal to study the pathology of CHP as well as to perform preclinical drug trials.

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Śladewski, Łukasz, Rafał Wereszczyński, Jerzy Majchrzak, Krzysztof Możejko, Wojciech Bujalski, Konrad Świrski, and Maks Sędzielski. "Close loop optimisation of large CHP based on approximation model." E3S Web of Conferences 137 (2019): 01051. http://dx.doi.org/10.1051/e3sconf/201913701051.

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Complex optimization of CHP plants becomes a very important issue in research and implementation, particularly in the context of increasing environmental requirements. The process in industrial CHP plants could be decomposed into several subprocesses, which could be optimized individually using dedicated solutions. The article presents the results of work of complex, multi-modular optimization project of one CHP plant located in petrochemical and refinery plant in Poland. The scope of the project is economical load dispatch optimizer aimed to increase economical profit of CHP operation, combustion optimization for boiler efficiency increase and NOX emission reduction, steam temperature advanced control for improved control quality, sootblowing optimization for reduction of steam demand for sootblowing process. The solution includes also measurement validation and correction system, which is based on data reconciliation algorithm and on-line performance monitoring system.

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Owaku, Takashi, Hiromi Yamamoto, and Atsushi Akisawa. "Optimal SOFC-CHP Installation Planning and Operation Model Considering Geographic Characteristics of Energy Supply Infrastructure." Energies 16, no. 5 (February 25, 2023): 2236. http://dx.doi.org/10.3390/en16052236.

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Combined heat and power (CHP) is crucial for promoting thorough energy conservation and advanced energy use, aimed toward greenhouse gas reduction. Solid oxide fuel cell (SOFC)-CHP is expected to be introduced as a measure against global warming and has been the focus of attention, and this study examined the effects of its introduction. This study introduces a linear programming evaluation model that can simulate optimized facility configuration and operation, based on the power supply and demand. The novelty of the proposed model is the consideration of geographic characteristics, which influences parameters dependent on gas transportation infrastructure and electricity. A sensitivity analysis was conducted considering the number of units and location of SOFC-CHP introductions in the National Capital Region of Japan. As a result, it was predicted that SOFC-CHP would likely begin to be introduced in areas where there is a large shadow price difference between electricity and gas at each node. The total power generation will decrease, as transmission and distribution losses decrease, owing to the diffusion of SOFC-CHP installed in the vicinity of demand. The widespread use of SOFC-CHP is an economically feasible CO2 emissions reduction pathway. These results will help assess the introduction of various distributed power sources in addition to SOFC-CHP to reduce CO2 emissions.

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Hughes, R. A., B. Ramsay, and C. Rossini. "A Knowledge-Based Decision Support System for Combined Heat and Power Investment Appraisal and Plant Selection." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 210, no. 1 (February 1996): 15–24. http://dx.doi.org/10.1243/pime_proc_1996_210_004_02.

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Combined heat and power (CHP) can, in the most suitable cases, reduce a consumer's total energy costs by up to 40 per cent. It is important to stress that CHP is not viable at all sites and further that poor choice of CHP plant often results in inefficient and uneconomic operation. It is therefore vitally important to build a clear picture of what specific factors determine the profitability of a CHP scheme. The development of an accurate, reliable economic model is necessary for any sector where a potential market for CHP exists. Conventional economic models have a number of limitations, particularly where situations involve a high degree of risk and uncertainty. This paper shows how decision analysis techniques can be combined with a conventional spreadsheet to overcome these weaknesses and demonstrates the power and flexibility of the resulting model with a case study.

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Şah, Sezgin, and M. Handan Çubuk. "CHP Microturbine Configuration Model and Economic Analysis." Cogeneration & Distributed Generation Journal 24, no. 2 (April 2009): 51–61. http://dx.doi.org/10.1080/15453660909509008.

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Jin, Xiao Long, Hai Feng Li, Tao Jin, Xian Dong Xu, Ming Shen Wang, and Jian Meng. "Economical and Coordinated Dispatch of CHP Based Microgrid with Renewable Energy Resources." Advanced Materials Research 960-961 (June 2014): 1022–28. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.1022.

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The advantages of high energy efficiency and economic benefit promote the wide application of combined heat and power system (CHP) based microgrid. Firstly, a mathematical model of the CHP based microgrid is developed. Then, a cost function for the coordination of heat and electric load is proposed. Finally, an optimal dispatch model is developed to achieve the economical and coordinated operation of the CHP based microgrid system. Simulation results verify effectiveness of the proposed dispatch model, which is a powerful tool for the energy management of CHP based microgrid with renewable energy resources.

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Razak, Amir A. "Library Structure of Dynamic Simulation for Combined Heat and Power Plant in Modelica Language." Applied Mechanics and Materials 110-116 (October 2011): 4925–31. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.4925.

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The most common form of energy recycling system is Combined Heat and Power (CHP) plants. The CHP plant is a complex system and still under intensive development by many researchers. The system needs to be developed in quick and efficient manners with low resources based on modeling and simulation method. With the development of CHP library in open source Modelica language, it could be used as a base for further advancement of CHP technology. The aim of this work is to design a structure of initial version of a model library for the dynamic simulation of Combined Heat and Power plants (CHP). Modular approach and top-down design have been implemented in the model library development. A solid base for this work is defined which includes rules in modeling the components (e.g. robustness and reusability), default library structure arrangement and model documentation. By strictly follow the rules and concepts introduced in this work, the mistakes in modeling is minimized. The designed library in Modelica language will provide an organized environment in modeling a CHP plant.

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De Souza, Ronelly, Melchiorre Casisi, Diego Micheli, and Mauro Reini. "A Review of Small–Medium Combined Heat and Power (CHP) Technologies and Their Role within the 100% Renewable Energy Systems Scenario." Energies 14, no. 17 (August 27, 2021): 5338. http://dx.doi.org/10.3390/en14175338.

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The energy transition towards a scenario with 100% renewable energy sources (RES) for the energy system is starting to unfold its effects and is increasingly accepted. In such a scenario, a predominant role will be played by large photovoltaic and wind power plants. At the same time, the electrification of energy consumption is expected to develop further, with the ever-increasing diffusion of electric transport, heat pumps, and power-to-gas technologies. The not completely predictable nature of the RES is their well-known drawback, and it will require the use of energy storage technologies, in particular large-scale power-to-chemical conversion and chemical-to-power re-conversion, in view of the energy transition. Nonetheless, there is a lack in the literature regarding an analysis of the potential role of small–medium CCHP technologies in such a scenario. Therefore, the aim of this paper is to address what could be the role of the Combined Heat and Power (CHP) and/or Combined Cooling Heat and Power (CCHP) technologies fed by waste heat within the mentioned scenario. First, in this paper, a review of small–medium scale CHP technologies is performed, which may be fed by low temperature waste heat sources. Then, a review of the 100% RE scenario studied by researchers from the Lappeenranta University of Technology (through the so-called “LUT model”) is conducted to identify potential low temperature waste heat sources that could feed small–medium CHP technologies. Second, some possible interactions between those mentioned waste heat sources and the reviewed CHP technologies are presented through the crossing data collected from both sides. The results demonstrate that the most suitable waste heat sources for the selected CHP technologies are those related to gas turbines (heat recovery steam generator), steam turbines, and internal combustion engines. A preliminary economic analysis was also performed, which showed that the potential annual savings per unit of installed kW of the considered CHP technologies could reach EUR 255.00 and EUR 207.00 when related to power and heat production, respectively. Finally, the perspectives about the carbon footprint of the CHP/CCHP integration within the 100% renewable energy scenario were discussed.

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Ling, Wen Choong, Viknesh Andiappan, and Yoke Kin Wan. "Design of Biomass Combined Heat and Power (CHP) Systems based on Economic Risk using Minimax Regret Criterion." MATEC Web of Conferences 152 (2018): 01006. http://dx.doi.org/10.1051/matecconf/201815201006.

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It is a great challenge to identify optimum technologies for CHP systems that utilise biomass and convert it into heat and power. In this respect, industry decision makers are lacking in confidence to invest in biomass CHP due to economic risk from varying energy demand. This research work presents a linear programming systematic framework to design biomass CHP system based on potential loss of profit due to varying energy demand. Minimax Regret Criterion (MRC) approach was used to assess maximum regret between selections of the given biomass CHP design based on energy demand. Based on this, the model determined an optimal biomass CHP design with minimum regret in economic opportunity. As Feed-in Tariff (FiT) rates affects the revenue of the CHP plant, sensitivity analysis was then performed on FiT rates on the selection of biomass CHP design. Besides, design analysis on the trend of the optimum design selected by model was conducted. To demonstrate the proposed framework in this research, a case study was solved using the proposed approach. The case study focused on designing a biomass CHP system for a palm oil mill (POM) due to large energy potential of oil palm biomass in Malaysia.

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Latosov, E., and A. Siirde. "Heat load model for small-scale CHP planning." Renewable Energy and Power Quality Journal 1, no. 08 (April 2010): 788–91. http://dx.doi.org/10.24084/repqj08.475.

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Polo, Christine, Jim Rowan, David Long, Patricia Scanlan, Hari Santha, Bobby Burchett, Steven Marshall, and Vic Godlewski. "Finding the Right Fit – CoGenie CHP Optimization Model." Proceedings of the Water Environment Federation 2014, no. 2 (October 1, 2014): 1–12. http://dx.doi.org/10.2175/193864714816196583.

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Saarinen, Jaakko, Matias Halinen, Jukka Ylijoki, Matti Noponen, Pekka Simell, and Jari Kiviaho. "Dynamic Model of 5kW SOFC CHP Test Station." Journal of Fuel Cell Science and Technology 4, no. 4 (June 22, 2006): 397–405. http://dx.doi.org/10.1115/1.2759502.

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A dynamical model for a 5kW class solid oxide fuel cell (SOFC) combined heat and power (CHP) test station has been composed using the APROS® environment. The model is based on a real test station being constructed and operated at VTT Technical Research Centre of Finland and it comprises the following main components of the real test system: the autothermal reforming unit, SOFC stack situated inside a furnace, catalytic afterburner, and three heat exchangers. The constructed model has been verified against experimental results obtained from the autothermal reforming unit, catalytic afterburner, and the two cathode side heat exchangers. The model has been used for the phenomenological studies of the system during current transient simulations using a simplified and fast zero-dimensional model including internal reforming reactions for the SOFC stack. The test station model was capable of operating at a speed of 18 times the real time using a standard personal computer.

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König, P., A. Weber, N. Lewald, T. Aicher, L. Jörissen, and E. Ivers-Tiffée. "Model-Aided Testing of a PEMFC CHP System." Fuel Cells 7, no. 1 (February 2007): 70–77. http://dx.doi.org/10.1002/fuce.200500208.

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Ko, Woong, and Jinho Kim. "Generation Expansion Planning Model for Integrated Energy System Considering Feasible Operation Region and Generation Efficiency of Combined Heat and Power." Energies 12, no. 2 (January 11, 2019): 226. http://dx.doi.org/10.3390/en12020226.

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Integrated energy systems can provide a more efficient supply than individual systems by using resources such as cogeneration. To foster efficient management of these systems, the flexible operation of cogeneration resources should be considered for the generation expansion planning model to satisfy the varying demand of energy including heat and electricity, which are interdependent and present different seasonal characteristics. We propose an optimization model of the generation expansion planning for an integrated energy system considering the feasible operation region and efficiency of a combined heat and power (CHP) resource. The proposed model is formulated as a mixed integer linear programming problem to minimize the sum of the annualized cost of the integrated energy system. Then, we set linear constraints of energy resources and describe linearized constraints of a feasible operation region and a generation efficiency of the CHP resource for application to the problem. The effectiveness of the proposed optimization problem is verified through a case study comparing with results of a conventional optimization model that uses constant heat-to-power ratio and generation efficiency of the CHP resource. Furthermore, we evaluate planning schedules and total generation efficiency profiles of the CHP resource for the compared optimization models.

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WANG, JIAHAI. "A MOLECULAR RECOGNITION MODEL FOR ENANTIOSELECTIVITY AND AUTOINDUCTION IN CYANOHYDRIN FORMATION CATALYZED BY CYCLO[(S)-HIS-(S)-PHE]." Journal of Theoretical and Computational Chemistry 09, no. 02 (April 2010): 495–510. http://dx.doi.org/10.1142/s0219633610005803.

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A molecular recognition mechanism based on dimeric model for cyclic dipeptide Cyclo[(S)-His-(S)-Phe] (abridged CHP) catalyzed autoinduction is proposed according to the inference of previous experimental findings, which is supported by theoretical calculation with Oniom(B3LYP/3-21G*:AM1) method. The most unstable CHP dimer whose intermolecular hydrogen bonds are immensely lessened by two intramolecular hydrogen bonds is defined as the highest active component (IIa) existing in solid among the three possible dimers (Ia, IIa, and IIb). The carbonyl group of benzaldehyde coordinates to CHP dimer (IIa) by a hydrogen bond with Phe–NαH rather than His–NαH and HCN interacted with the imidazole moiety of His residue to form cyanide ion. In view of the theoretical calculation and experimental results, the structures of the nine-ring complexes derived from interaction between catalytic active dimer CHP(IIa) and cyanohydrins were postulated to explain the enantioselective autoinduction: The structure of no nitrile involved six-ring complex derived from interaction between catalytic active dimer CHP(IIa) and cyanohydrins were postulated to explain the elimination of enantioselective autoinduction.

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Ma, Zhao, Huiru Zhao, Qun Su, and Xuejie Wang. "Distributionally Robust Optimal Dispatching of CHP Microgrid considering Concentrating Solar Power and Uncertainty." Mathematical Problems in Engineering 2022 (April 26, 2022): 1–15. http://dx.doi.org/10.1155/2022/1994063.

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In order to solve the problem of diversified low-carbon energy supply with renewable energy as the main body, concentrating solar power (CSP) stations are introduced to act as cogeneration units. Taking full advantage of the flexible coupling and multienergy complementarity of electric, heat, and gas, an economic dispatch method for combined heat and power microgrid systems (CHP microgrid) with interconnected electric, heat, and gas is proposed. First, build the CSP-CHP microgrid structure and model the main equipment. Then, aiming at the minimum operating cost of the system, a regular scheduling model of the CSP-CHP microgrid system is established. On this basis, in order to deal with the uncertainty of renewable energy output, a distributionally robust optimization (DRO) model is introduced. In the DRO model, the Kullback–Leibler (KL) divergence is used to construct an ambiguity set about the predicted error of renewable energy output, and finally, the CSP-CHP microgrid DRO economic dispatch model is established. Finally, the system is simulated and analyzed in a typical CSP-CHP microgrid system, and the feasibility and effectiveness of the proposed method are verified by analysis. In addition, the necessity of introducing CSP and the advantages of the DRO model is further explained by comparison.

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Gonzalez-Castellanos, Alvaro, Priyanko Guha Thakurta, and Aldo Bischi. "Congestion management via increasing integration of electric and thermal energy infrastructures." E3S Web of Conferences 238 (2021): 05005. http://dx.doi.org/10.1051/e3sconf/202123805005.

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Congestion caused in the electrical network due to renewable generation can be effectively managed by integrating electric and thermal infrastructures, the latter being represented by large scale District Heating (DH) networks, often fed by large combined heat and power (CHP) plants. The CHP plants could further improve the profit margin of district heating multi-utilities by selling electricity in the power market by adjusting the ratio between generated heat and power. The latter is possible only for certain CHP plants, which allow decoupling the two commodities generation, namely the ones provided by two independent variables (degrees-of-freedom) or by integrating them with thermal energy storage and Power-to-Heat (P2H) units. CHP units can, therefore, help in the congestion management of the electricity network. A detailed mixed-integer linear programming (MILP) optimization model is introduced for solving the network-constrained unit commitment of integrated electric and thermal infrastructures. The developed model contains a detailed characterization of the useful effects of CHP units, i.e., heat and power, as a function of one and two independent variables. A lossless DC flow approximation models the electricity transmission network. The district heating model includes the use of gas boilers, electric boilers, and thermal energy storage. The conducted studies on IEEE 24 bus system highlight the importance of a comprehensive analysis of multi-energy systems to harness the flexibility derived from the joint operation of electric and heat sectors and managing congestion in the electrical network.

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Liu, Lu. "Improving seismic image using the common-horizon panel." GEOPHYSICS 84, no. 5 (September 1, 2019): S449—S458. http://dx.doi.org/10.1190/geo2018-0656.1.

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Generating high-quality seismic images requires accurate velocity models. However, velocity errors are predictably brought into the models. To mitigate the influences of velocity errors, we have used the common-horizon panel (CHP) for migration velocity analysis. CHP provides quantitative information to adjust mispositioned interfaces or correct deformed wavefields, which leads to improved image quality. It is generated by extrapolating seismic gathers to a selected target horizon and applying the time-shift imaging condition. Compared with the commonly used common-image gathers, the events in CHPs are more trackable because geologic interfaces are typically continuous in space. For a correct velocity model, the panel indicates a flat event at zero time lag, whereas in the case of an erroneous velocity model, the event becomes kinematically oscillating. This distinguishing difference provides a practical criterion to verify whether the migration velocity model is correct and to estimate the velocity or wavefield errors based on how much the event deviates from zero time lag. Tests on synthetic and field data sets have shown that the seismic images are improved by using the proposed CHP technique.

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Lonkwic, Paweł. "A MATHEMATICAL MODEL OF CHP 2000 TYPE PROGRESSIVE GEAR." Advances in Science and Technology Research Journal 10, no. 32 (December 1, 2016): 150–55. http://dx.doi.org/10.12913/22998624/65120.

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Feldman, Tatyana, Denise Zou, Mayvis Rebeira, Joseph Lee, Mack Harris, Wenkang Ma, Michelle A. Fanale, et al. "Cost-Effectiveness of brentuximab vedotin with chemotherapy in frontline treatment of CD30-expressing peripheral T-cell lymphoma." Journal of Clinical Oncology 37, no. 15_suppl (May 20, 2019): e19060-e19060. http://dx.doi.org/10.1200/jco.2019.37.15_suppl.e19060.

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e19060 Background: The most common frontline treatment for peripheral T-cell lymphoma (PTCL) is cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or a CHOP-like regimen. In the recently reported phase 3 ECHELON-2 trial, brentuximab vedotin (BV) in combination with CHP (A+CHP) demonstrated significant improvement in progression-free survival (PFS) and overall survival (OS) compared to CHOP, with a manageable safety profile. The objective of this analysis was to evaluate the cost-effectiveness of A+CHP in the frontline setting for CD30-expressing PTCL. Methods: A partitioned survival model consisting of 3 health states (PFS, post progression survival, and death), was constructed using clinical and quality of life data from ECHELON-2 from a US payer perspective over a lifetime time horizon. PFS and OS observed from ECHELON-2 were extrapolated using standard parametric distributions. The best-fitting distributions (log-normal for both arms) were selected based on statistical goodness of fit and clinical plausibility of the long-term projections. Health utilities were derived from the European Quality of Life 5-Dimensions (EQ-5D) data collected in ECHELON-2. The average utility scores for the pre- and post-progression periods were estimated via a repeated-measures mixed-effects model. Medical resource use and costs were from literature. Results: The model predicted A+CHP extended undiscounted PFS by 2.92 and OS by 3.38 years over CHOP. These survival gains drive the value in the model. After adjusting for quality of life and discounting, A+CHP was associated with 1.79 quality-adjusted life years (QALYs) gained at an incremental cost of $176,842, yielding an incremental cost-effectiveness ratio (ICER) of $98,987. Sensitivity analyses of alternative model assumptions provided ICERs from $64,000 to $154,000. The estimated probability that A+CHP is cost-effective compared with CHOP was 75% at a willingness-to-pay threshold of $150,000. Conclusions: Based on the ECHELON-2 trial data, this analysis showed for patients with previously untreated CD30-expressing PTCL, treatment with BV in combination with CHP is likely to be cost-effective in comparison to CHOP.

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Li, Rui, and Peng Li. "Community Based of CHP Microgrid Optimal Operation." Advanced Materials Research 981 (July 2014): 673–76. http://dx.doi.org/10.4028/www.scientific.net/amr.981.673.

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This paper presents a community-based CHP microgrid model for optimal operation. The model introduces a microgrid controller and consumption parameters, and that the existing restrictions, the optimization of microgrid operation.bacterial foraging optimization(BFO) algorithm was used to develop microgrid problems. Test results show the effectiveness of the model micro-grid operation.

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Genovski, Ivan, and Kaloyan Hristov. "Model research of the energy efficiency of a cogeneration backpressure steam turbine installation." E3S Web of Conferences 207 (2020): 02004. http://dx.doi.org/10.1051/e3sconf/202020702004.

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In the contemporary district heating systems (DHS) heat energy for the customers is generated by cogeneration method, which leads to the saving of primary energy resources compared to the separate production method. The most widespread technology for combined production is based on steam turbine installations with adjustable steam extraction and backpressure steam turbine. In these technologies district heating water is heated to the required temperature either in district heaters in case of steam turbine with adjustable steam extractions or in boiler-condenser in case of backpressure steam turbine installations. The temperature of the district heat water at the inlet of the CHP installation depends on the mode of operation of the DHS. The heat load, distributed to consumers, is regulated at the heat source (CHP installation) by temperature and flow rate of the district heating water, mainly following the change in climatic factors. Current study presents the development of a simulation model of existing CHP backpressure steam turbine. The object studied is a backpressure steam turbine type SST-300 CE2L/V36S. Presented are results from the validation of the simulated model with data from the design documentation. The model has been used to study the energy efficiency of a steam turbine installation based on multivariate simulation calculations. The results obtained relate the energy efficiency indicators of CHP backpressure steam turbine with the factors that characterize the mode of operation of the district heating system.

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Banica, Florinel G., and Ana Ion. "Electrochemical Investigations of the Nickel(II)-Penicillamine System. 3. A Study of the Catalytic Hydrogen Prewave in Connection with Structure of Nickel(II)-Penicillamine Complexes." Collection of Czechoslovak Chemical Communications 65, no. 6 (2000): 995–1013. http://dx.doi.org/10.1135/cccc20000995.

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The catalytic hydrogen evolution on the dropping mercury electrode in the presence of Ni(II) and D-penicillamine (Pen) at pH around 6 yields a catalytic hydrogen prewave (CHP) with E1/2 = -1.21 V vs SCE. This wave is similar to the CHP produced by selenocysteine and cysteine described previously. The occurrence of the CHP depends on the formation of the mono(D-penicillamine-N,S)nickel(II) complex whereas bis(D-penicillamine-N,S)nickel(II) complex is inert and has no influence on the CHP electrode process. Although the analogous bis(cysteine) complex is labile, there is strong evidence that it does not take part directly in the CHP process in the Ni(II)-cysteine system. The actual proton donor in the CHP electrode process is the hydronium ion and not the acid component of the buffer. A tentative reaction mechanism was formulated with emphasis on the state of the intermediate hydrogen species. The characteristic pH, nickel ion involvement and the structure of the ligand make the CHP process an attractive model for hydrogen redox reactions catalyzed by [NiFe] hydrogenase.

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Kelly, N. J., J. A. Clarke, A. Ferguson, and G. Burt. "Developing and testing a generic micro-combined heat and power model for simulations of dwellings and highly distributed power systems." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 222, no. 7 (October 24, 2008): 685–95. http://dx.doi.org/10.1243/09576509jpe532.

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This paper elaborates an approach to the modelling of domestic micro-combined heat and power (μ-CHP) using a building simulation tool that can provide a detailed picture of the environmental performance of both the μ-CHP heating system and the dwelling it serves. The approach can also provide useful data for the modelling of highly distributed power systems (HDPS). At the commencement of the work described in this paper no μ-CHP device model that was compatible with a building simulation tool was available. The development of such a model is described along with its calibration and verification. The simulation tool with the device model was then applied to the analysis of a dwelling with a Stirling engine-based heating system. Different levels of thermal insulation and occupancy types were modelled. The energy and environmental performance of the μ-CHP device was quantified for each case; additionally, the potential for its participation in the control and operation of an HDPS was assessed. Analysis of the simulation results indicated that the parasitic losses associated with the μ-CHP system balance of plant reduced the overall heating system efficiency by up to 40 per cent. Performance deteriorated with increasing levels of insulation in the dwelling, resulting in reduced thermal efficiency and increased cycling, though overall fuel use was reduced. The analysis also indicated that the device was generally available to participate in HDPS control for greater than 90 per cent of the simulation time. The potential length of the participation time ranged from 1 to 800+min and depended upon the state of the μ-CHP system thermal buffer and prevailing heat loads. Probabilities for different participation times and modes were calculated.

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Guo, Junshan, Wei Zheng, Zhuang Cong, Panfeng Shang, Congyu Wang, and Jiwei Song. "Steam-Water Modelling and the Coal-Saving Scheduling Strategy of Combined Heat and Power Systems." Energies 15, no. 1 (December 26, 2021): 141. http://dx.doi.org/10.3390/en15010141.

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China aims to peak carbon emissions by 2030. As a result, small-scale coal-fired combined heat and power (CHP) units and self-provided units are gradually shut down, and large-scale coal-fired CHP units are a solution to undertake the industrial heat loads. From the perspective of the industrial heat load allocation during the non-heating season, the problems regarding the coal-saving scheduling strategy of coal-fired CHP units are addressed. The steam-water equations of CHP units are established to analyze the heat-power coupling characteristics. The energy utilization efficiency, exergy efficiency and the coal consumption are analyzed. The optimization model of saving coal consumption is established and the adaptive mutation particle swarm optimization (AMPSO) is introduced to solve the above model. The 330 MW coal-fired CHP unit is taken as an example, and the results show that for the constant main flow rate, each increase of 1 t/h industrial steam extraction will reduce the power output by about 0.321 MW. The energy utilization efficiency and the exergy are mainly influenced by industrial steam supply and the power load, respectively. For the CHP system with two parallel CHP units, the unequal allocation of industrial heat load between two units saves more coal than equal allocation. The coal consumption can be reduced when the unit with lower power load undertakes more industrial heat load. In the typical day, the total coal consumption after optimization is 3203.92 tons, a decrease of 14.66 tons compared to the optimization before. The two CHP units in the case can benefit about 5,612,700 CHY extra in one year.

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Lyu, Quan, Haoyan Gong, Nan Yang, Xiandong Xu, Na Zhang, and Haixia Wang. "An Evaluation Method of Wind Power Integration in Power Systems with Flexible Combined Heat and Power Plant." Energies 12, no. 21 (October 30, 2019): 4129. http://dx.doi.org/10.3390/en12214129.

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During the heating period in Northeast China, the electricity generated by Combined Heat and Power (CHP) plants has caused a large amount of wind power curtailment. To avoid this curtailment, Heat Storages (HS) and Electric Boilers (EB) are being widely applied to CHP plants. However, the effectiveness of HS and EB on the curtailment of wind power has still not been well evaluated. This paper proposes a new evaluation method consisting of an operation boundary model and an internal coordinated operation model for each flexible CHP plant with HS and EB. Then a system power balance model based on hour-by-hour analysis is established to determine the wind power integration, down-regulation subsidy and the utilization degree of the flexible equipment. The models are validated by using field measured data of a province in China. The results show that the capacity change of the EB has a bigger impact on the down-regulation subsidy than that of the HS, while the EB is more effective when the level of wind power integration is high.

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Gbadamosi, Saheed Lekan, and Nnamdi I. Nwulu. "Optimal Power Dispatch and Reliability Analysis of Hybrid CHP-PV-Wind Systems in Farming Applications." Sustainability 12, no. 19 (October 5, 2020): 8199. http://dx.doi.org/10.3390/su12198199.

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Renewable energy sources (RES) are seen as potential alternative energy sources for rural communities to meet energy demand where electricity supply is inaccessible. Wind and Photo-Voltaic (PV) power is seen as mature and sustainable alternatives for rural electrification. This paper discusses the optimal power dispatch for hybrid combined heat and power (CHP), wind, PV and battery systems with a view to determining the operation of the hybrid system for farming applications. This is accomplished by considering the basic power system probability concepts to assess the performance of the reliability indices. The proposed mathematical model seeks to minimize the system operation costs from CHP. The developed model was validated on five case studies with the same load profile, solar radiation, wind speed and CHP generating unit parameters and solved using a CPLEX solver embedded in Algebraic Modelling Language. The sensitivity analysis performed indicates that the hybrid system achieved a higher reliability as compared to other case studies. The result shows 48% of energy cost reduction is achievable when considering the proposed hybrid CHP, wind, PV and battery system as compared to energy supply via CHP.

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Kang, Ying Wei, Wei Huang, Yang Xue, Guang Yi Cao, and Heng Yong Tu. "Dynamic Simulation of a Solid Oxide Fuel Cell System for Micro Combined Heat and Power Application." Applied Mechanics and Materials 336-338 (July 2013): 695–99. http://dx.doi.org/10.4028/www.scientific.net/amm.336-338.695.

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In the past decade, developing solid oxide fuel cell (SOFC) systems for micro combined heat and power applications (micro-CHP, 1-10 kWe) is one of the hot spots in the world energy field. To meet the requirements for system optimization and control design of SOFC micro-CHP systems, in this paper a dynamic model of an SOFC micro-CHP system is developed, based on which dynamic simulations are also carried out. Simulation results show that the present model can reflect the behavior of the SOFC micro-CHP system quite well; the influence of one component on another is an important factor to determine system dynamic behavior; as the system comprises many components and concerns different physical and chemical processes, it has dynamic processes with several kinds of time scales; for the air preheating need, the heat-exchange area of air pre-heater is quite big, which leads to its big thermal inertia, and causes the dynamic process lasting for several ten thousands of seconds.

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Weiler, Verena, Jonas Stave, and Ursula Eicker. "Renewable Energy Generation Scenarios Using 3D Urban Modeling Tools—Methodology for Heat Pump and Co-Generation Systems with Case Study Application †." Energies 12, no. 3 (January 28, 2019): 403. http://dx.doi.org/10.3390/en12030403.

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In the paper, a method was developed to automatically dimensionalize and calculate central energy generation and supply scenarios with a district heating system for cities based on 3D building models in the CityGML format and their simulated heat demand. In addition, the roof geometry of every individual building is used to model photovoltaic energy generation potential. Two types of supply systems, namely a central heat pump (HP) system and a large co-generation (combined heat and power-CHP) system (both with a central storage and district distribution system), are modeled to supply the heat demand of the area under investigation. Both energy generation models are applied to a case study town of 1610 buildings. For the HP scenario, it can be shown that the case study town’s heat demand can be covered by a monovalent, low-temperature system with storage, but that the PV only contributes 15% to the HP electricity requirement. For the CHP scenario, only 61% of the heat demand can be covered by the CHP, as it was designed for a minimum of 4000 operating hours. Both the PV and the CHP excess electricity are fully injected into the grid. As a result, the primary energy comparison of both systems strongly depends on the chosen primary energy factors (PEF): with given German regulations the CHP system performs better than the HP system, as the grid-injected electricity has a PEF of 2.8. In the future, with increasingly lower PEFs for electricity, the situation reverses, and HPs perform better, especially if the CHP continues to use natural gas. Even when renewable gas from a power to gas (P2G) process is used for the CHP, the primary energy balance of the HP system is better, because of high conversion losses in the P2G process.

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Xu, Ye, Na Meng, Xu Wang, Junyuan Tan, and Wei Li. "A Multiobjective Fractional Programming for a CHP System Operation Optimization Based on Energy Intensity." Energies 15, no. 6 (March 8, 2022): 1965. http://dx.doi.org/10.3390/en15061965.

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The objective of this research is to establish a multiobjective fractional programming (MOFP) model for supporting the operational management of a combined heat and power (CHP) system. Compared with the traditional operational optimization model of the CHP system, the importance of the energy intensity (i.e., the ratio of energy consumption and energy production) was emphasized in the MOFP model, which is considered as the system objective for replacing the common objective of minimizing the economic cost. This innovative transformation effectively reduces excessive energy consumption, accompanied by improvement in the system revenue. The CHP system of an industrial park in the City of Jinan, China, was used as a study case for demonstration. The obtained results reflected that the combination of two gas turbines (GTs) ensured safe, efficient, and stable output for meeting daily power requirements in various seasons. As for the steam load, during the summer, two heat recovery steam generators (HRSGs) play a major role, where the insufficient part is supplemented by two gas-fired boilers (SBs); conversely, the steam load in winter is mainly satisfied by the aid of two SBs. The successful application of the MOFP model in the park could provide a good demonstration for CHP management in many other districts and cities.

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Hagan, Donald L., Elena A. Mikhailova, Timothy M. Shearman, Patrick T. Ma, Jedidah S. Nankaya, Samantha K. Hart, Hillary E. Valdetero, William C. Bridges, and He Yun. "The Role of Soil and Landscape Factors in Chinese Privet (Ligustrum sinense) Invasion in the Appalachian Piedmont." Invasive Plant Science and Management 7, no. 3 (September 2014): 483–90. http://dx.doi.org/10.1614/ipsm-d-14-00002.1.

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AbstractThere is a limited understanding about the ecological mechanisms that enable certain plant species to become successful invaders of natural areas. This study was conducted to determine the soil and landscape characteristics that correlate with invasion of Chinese privet (CHP), and to develop a model to predict the probability of CHP invasion in Piedmont forests. A landscape ecosystem classification (LEC) system—based on the percentage of clay in the B horizon, depth to maximum clay (cm), exposure, terrain shape, and aspect (degrees)—was used to determine the soil moisture characteristics of invaded and uninvaded plots. Additional measurements included the cover classes of CHP and other species, litter depth (cm), slope (degrees), overstory basal area (m2 ha−1), and soil chemical properties. CHP invasion was negatively correlated with overstory basal area and slope and positively with litter depth and pH. A stepwise logistic regression model containing these four variables was highly sensitive, with an overall accuracy of 78%. Given the accuracy of this model, we propose that it can be used to calculate the probability of invasion in a given area, provided that some basic, readily obtainable site characteristics are known.

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Kambhampati, Swetha, Monica Saumoy, Stacy Pak, L. Elizabeth Budde, Matthew Genyeh Mei, Leslie Popplewell, Yi-Ping Wen, et al. "Cost effectiveness of polatuzumab vedotin in combination with chemoimmunotherapy (Pola-R-CHP) in previously untreated diffuse large B-cell lymphoma." Journal of Clinical Oncology 40, no. 16_suppl (June 1, 2022): 7568. http://dx.doi.org/10.1200/jco.2022.40.16_suppl.7568.

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7568 Background: In patients with treatment naive diffuse large B-cell lymphoma (DLBCL), the POLARIX study demonstrated a 6.5% improvement in the 2-year (yr) progression-free survival (PFS) with no difference in overall survival or safety using polatuzumab vedotin + R-CHP compared to standard RCHOP. We evaluated the cost effectiveness of pola-R-CHP for DLBCL. Methods: We modeled a hypothetical cohort of US adults (mean age, 58 yrs) with treatment naïve DLBCL by developing a Markov model with a 1-month cycle and 20-yr horizon. The cost-effectiveness of two strategies were directly compared (pola-R-CHP, RCHOP) using a range of plausible long-term outcomes. A patient with DLBCL in remission after treatment could develop subsequent progression or relapse, death, or alternative toxicity. Progression rates and overall survival were estimated from POLARIX study. Outcome measures were reported in incremental cost-effectiveness ratios (ICERs), with a willingness-to-pay (WTP) threshold of $150,000/quality-adjusted life-yr (QALY). Results: Assuming a 5-yr PFS of 69.6% with pola-R-CHP and 62.6% with RCHOP, pola-R-CHP was more effective (0.81 incremental QALYs) but more costly ($66,218) and was cost-effective at a WTP of 150,000 (ICER $82,220/QALY). Its cost effectiveness was highly dependent on the 5-yr PFS of pola-R-CHP with it no longer being cost effective if the 5-yr PFS was < 65%. One way sensitivity analysis demonstrated that pola-R-CHP is cost effective up to a cost of $270,506 at a WTP of $150,000. Probabilistic sensitivity analysis was derived from performing 10,000 Monte-Carlo model iterations and demonstrated that pola-R-CHP was the cost-effective strategy in 61.3% of iterations with RCHOP being cost-effective in 38.6% of iterations at a WTP of $150,000. Conclusions: If the absolute benefit in PFS is maintained over time, frontline pola-R-CHP for treatment of DLBCL would be cost effective at its current cost when compared to RCHOP at a WTP of $150,000/QALY. However, its cost effectiveness is highly sensitive to changes in long-term PFS and the cost of pola-R-CHP. If pola-R-CHP is adopted as frontline therapy for the 29,108 incident cases of DLBCL annually in the US, this will lead to an additional 1.8 billion dollars in healthcare expenditures. This highlights the importance of decreasing the cost of pola-R-CHP and identifying sub-populations that derive the highest benefit from it.[Table: see text]

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Carnovali, Marta, Gina Ramoni, Giuseppe Banfi, and Massimo Mariotti. "Herbal Preparation (Bromelain, Papain, Curcuma, Black Pepper) Enhances Mineralization and Reduces Glucocorticoid-Induced Osteoporosis in Zebrafish." Antioxidants 10, no. 12 (December 14, 2021): 1987. http://dx.doi.org/10.3390/antiox10121987.

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Natural foods with antioxidant properties, such as curcuma, papain, bromelain and black pepper, have been indicated as a potential natural therapeutic approach against osteoporosis. Zebrafish are an excellent animal model to study the effects of herbal preparations on osteogenesis and bone metabolism, both in physiological and in pathological conditions. Our study was aimed at evaluating whether curcuma-bromelain-papain-pepper herbal preparation (CHP) administered in embryos and adult fish is capable of promoting bone wellness in physiological and osteoporotic conditions. The effect of CHP has been studied in embryonic osteogenesis and glucocorticoid-induced osteoporosis (GIOP) in an adult fish model in which drug treatment induces a bone-loss phenotype in adult scales very similar to that which characterizes the bones of human patients. CHP prevented the onset of the osteoporotic phenotype in the scales of GIOP in adult zebrafish, with the osteoblastic and osteoclastic metabolic activity maintaining unaltered. CHP is also able to attenuate an already established GIOP phenotype, even if the alteration is in an advanced phase, partially restoring the normal balance of the bone markers alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) and stimulating anabolic reparative processes. The results obtained indicated CHP as a potential integrative antioxidant therapy in human bone-loss diseases.

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He, Liangce, Zhigang Lu, Lili Pan, Hao Zhao, Xueping Li, and Jiangfeng Zhang. "Optimal Economic and Emission Dispatch of a Microgrid with a Combined Heat and Power System." Energies 12, no. 4 (February 14, 2019): 604. http://dx.doi.org/10.3390/en12040604.

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With the rapid development of the new concept of energy internet, electric power systems often need to be investigated together with thermal energy systems. Additionally, to reduce pollution from gas emissions, it is very important to study the economic and emission dispatch of integrated electrical and heating systems. Hence, this paper proposes a multi-objective optimization dispatch model for a microgrid (MG) with a combined heat and power (CHP) system. This CHP-based MG system consists of a CHP unit, a wind turbine, a PV system, a fuel cell, an electric boiler, an electric storage, and a heat storage. It can exchange electricity with the distribution network and exchange heat with the district heating network. Minimum economic cost and minimum environmental cost are considered as the two objectives for the operation of this CHP-based MG system. To solve the two objective optimization problem, the multi-objective bacterial colony chemotaxis algorithm is utilized to obtain the Pareto optimal solution set, and the optimal solution is chosen by the Technique for Order of Preference by Similarity to Ideal Solution method. Finally, numerical case studies demonstrate the effectiveness of proposed model and method for the optimal economic and emission dispatch of the CHP-based MG system.

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Stanek, Wojciech, and Michał Budnik. "Exergy diagnosis of coal fired CHP plant with application of neural and regression modelling." Thermal Science 16, no. 3 (2012): 773–87. http://dx.doi.org/10.2298/tsci120509133s.

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Mathematical models of the processes, that proceed in energetic machines and devices, in many cases are very complicated. In such cases, the exact analytical models should be equipped with the auxiliary empirical models that describe those parameters which are difficult to model in a theoretical way. Regression or neural models identified basing on measurements are rather simple and are characterized by relatively short computation time. For this reason they can be effectively applied for simulation and optimization of steering and regulation processes, as well as, for control and thermal diagnosis of operation (eq. power plants or CHP plants). In the paper regression and neural models of thermal processes developed for systems of operation control of thermal plants are presented. Theoretical-empirical model of processes proceeding in coal fired CHP plant have been applied. Simulative calculations basing on these models have been carried out. Results of simulative calculations have been used for the exergetic evaluation of considered power plant. The diagnosis procedure let to investigate the formation of exergy costs in interconnected components of the system of CHP, as well as, investigate the influence of defects in operation of components on exergy losses and on the exergetic cost in other components.

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Khassouani, Chems-Eddouha, Abdellatif Asri, and Abdelmajid Soulaymani. "Risk management and surveillance systems: A Model proposed for the provincial public hospital (CHP)." E3S Web of Conferences 319 (2021): 01061. http://dx.doi.org/10.1051/e3sconf/202131901061.

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During the Covid-19 pandemic, the provincial hospitals (CHP) of Morocco have demonstrated a remarkable capacity for reactivity. They were able to reorganize themselves to ensure the response to the pandemic and maintain basic functions. However, this reactivity alone does not prove their resilience in the face of new infections and possible disasters. The CHP must plan its responsiveness well in advance by building an intra-hospital health vigilance system that meets basic provincial requirements and that communicates with its internal and external environments. A qualitative analysis, using the focus group method, on Ifrane hospital risk management system revealed that, the systems for notification and declaration of adverse events are set up under the responsibility of multiple actors and using multiple notification forms. The processes and procedures are not clear with an overlap between the activities of quality assurance, risk management and complaints treatment system. A lot of information does not arrive at its destination on time, which impacts decision-making. This work proposes a hospital risk management model with two systems, one for safety of care and the other for risk management, taking into account the missions of the CHP and the different sources of information.

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Hussain, Fida, M. Ashfaq Ahmad, Saeed Badshah, Rizwan Raza, M. Ajmal Khan, Saleem Mumtaz, Saad Dilshad, Raja Ali Riaz, M. Jafar Hussain, and Ghazanfar Abbas. "A modeling approach for low-temperature SOFC-based micro-combined heat and power systems." International Journal of Modern Physics B 33, no. 04 (February 10, 2019): 1950001. http://dx.doi.org/10.1142/s0217979219500012.

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The world’s challenge is to determine a more efficient, economical and environmental-friendly energy source to compete and replace the ongoing conventional energy resources. Solid oxide fuel cells (SOFCs) provide a highly efficient system to use divergent energy resources and have proved to provide the cleanest energy, least energy use, and lowest emissions. A techno-economic study is required to investigate the model design for SOFC-based micro-combined heat and power (m-CHP) systems for applications in terms of educational and commercial buildings. This work models and explores the optimized application of hydrogen gas-fueled SOFC-based m-CHP systems in educational buildings. Two educational departments’ loads are presented and model of SOFC-based m-CHP system against the different electric power demands is performed, in order to provide a techno-economic assessment of the technology. For successful development of the technology, results are related to system rightsizing, operating strategies, thermal to electric ratios, and match between end-use, with an aim towards classifying the overall feasibility and essential application requirements.

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Ziebik, A., M. Warzyc, and P. Gładysz. "Determination of the Optimal Structure of Repowering a Metallurgical CHP Plant Fired with Technological Fuel Gases." Archives of Metallurgy and Materials 59, no. 1 (March 1, 2014): 105–16. http://dx.doi.org/10.2478/amm-2014-0017.

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Abstract CHP plants in ironworks are traditionally fired with low-calorific technological fuel gases and hard coal. Among metallurgical fuel gases blast-furnace gas (BFG) dominates. Minor shares of gaseous fuels are converter gas (LDG) and surpluses of coke-oven gas (COG). Metallurgical CHP plant repowering consists in adding a gas turbine to the existing traditional steam CHP plant. It has been assumed that the existing steam turbine and parts of double-fuel steam boilers can be used in modernized CHP plants. Such a system can be applied parallelly with the existing steam cycle, increasing the efficiency of utilizing the metallurgical fuel gases. The paper presents a method and the final results of analyzing the repowering of an existing metallurgical CHP plant fired with low-calorific technological fuel gases mixed with hard coal. The introduction of a gas turbine cycle results in a better effectiveness of the utilization of metallurgical fuel gases. Due to the probabilistic character of the input data (e.g. the duration curve of availability of the chemical energy of blast-furnace gas for CHP plant, the duration curve of ambient temperature) the Monte Carlo method has been applied in order to choose the optimal structure of the gas-and-steam combined cycle CHP unit, using the Gate Cycle software. In order to simplify the optimizing calculation, the described analysis has also been performed basing on the average value of availability of the chemical energy of blast-furnace gas. The fundamental values of optimization differ only slightly from the results of the probabilistic model. The results obtained by means of probabilistic and average input data have been compared using new information and a model applying average input data. The new software Thermoflex has been used. The comparison confirmed that in the choice of the power rating of the gas turbine based on both computer programs the results are similar.

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Tarasova, Victoria. "FACTOR ANALYSIS OF THE THERMAL SCHEME OF CHP WITH SUPER CRITICAL STEAM CYCLE ON THE BASIS OF EXERGY METHOD." Bulletin of the National Technical University «KhPI» Series: New solutions in modern technologies, no. 2(8) (June 15, 2021): 46–55. http://dx.doi.org/10.20998/2413-4295.2021.02.07.

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The most promising direction of CHP modernization is the introduction of power units on supercritical steam parameters. Increasing steam parameters is one of the most effective ways to increase the efficiency of a CHP plant. Thus, the development of the concept of thermal schemes turbines for supercritical steam parameters, taking into account the characteristics of their operation at the existing CHP Ukraine is an actual scientific problem. The solution to this problem will make it possible to replace or modernize the power generating equipment that has exhausted its resource with modern power units that meet world economic and environmental standards. The method of exergy analysis is adapted to the study of thermal schemes of CHP plants with supercritical steam cycle. As an example of application of a method the exergy analysis of the power plant working on the one-stage thermal scheme is carried out. Within the framework of the proposed method, a thermodynamic and topology-exergetic model of the power plant is created. Based on the topology-exergetic model the indicators of thermodynamic efficiency of the power plant operating on supercritical parameters of steam are determined. It is proposed to apply the theory of experiment planning in exergy analysis of the thermal circuit of a CHP. With the involvement of this theory, a multifactor numerical experiment was conducted to determine the impact on the exergetic efficiency of the thermal scheme of CHP of the main determining variable factors, such as adiabatic and thermal efficiency of the plant, as well as the operating parameters. The generalized equation of functional interrelation of exergetic efficiency of system and exergetic efficiency of elements of thermal scheme of CHP is received. The proposed equation can be used as a tool for further training of neural networks and their application both in the design and in the diagnosis of energy efficiency of CHP. According to the results of the factor analysis, a rather high conservatism of the considered one-stage scheme of CHP to the change of the varied parameters was revealed. This indicates the presence of more rigid structural links between the elements, which is generally a positive aspect of the reconstruction.

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Allman, Erik, Qian Wang, Rachel L. Walker, Molly Austen, Maureen A. Peters, and Keith Nehrke. "Calcineurin homologous proteins regulate the membrane localization and activity of sodium/proton exchangers in C. elegans." American Journal of Physiology-Cell Physiology 310, no. 3 (February 1, 2016): C233—C242. http://dx.doi.org/10.1152/ajpcell.00291.2015.

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Calcineurin B homologous proteins (CHP) are N-myristoylated, EF-hand Ca2+-binding proteins that bind to and regulate Na+/H+ exchangers, which occurs through a variety of mechanisms whose relative significance is incompletely understood. Like mammals, Caenorhabditis elegans has three CHP paralogs, but unlike mammals, worms can survive CHP loss-of-function. However, mutants for the CHP ortholog PBO-1 are unfit, and PBO-1 has been shown to be required for proton signaling by the basolateral Na+/H+ exchanger NHX-7 and for proton-coupled intestinal nutrient uptake by the apical Na+/H+ exchanger NHX-2. Here, we have used this genetic model organism to interrogate PBO-1's mechanism of action. Using fluorescent tags to monitor Na+/H+ exchanger trafficking and localization, we found that loss of either PBO-1 binding or activity caused NHX-7 to accumulate in late endosomes/lysosomes. In contrast, NHX-2 was stabilized at the apical membrane by a nonfunctional PBO-1 protein and was only internalized following its complete loss. Additionally, two pbo-1 paralogs were identified, and their expression patterns were analyzed. One of these contributed to the function of the excretory cell, which acts like a kidney in worms, establishing an alternative model for testing the role of this protein in membrane transporter trafficking and regulation. These results lead us to conclude that the role of CHP in Na+/H+ exchanger regulation differs between apical and basolateral transporters. This further emphasizes the importance of proper targeting of Na+/H+ exchangers and the critical role of CHP family proteins in this process.

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Kane, Gabrielle M. "Step-by-step: A model for practice-based learning." Journal of Continuing Education in the Health Professions 27, no. 4 (2007): 220–26. http://dx.doi.org/10.1002/chp.141.

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Ahn, Samuel S., Wesley S. Moore, Terry L. Kaiura, and Martin D. Shickman. "The endovascular training model for continuing medical education courses." Journal of Continuing Education in the Health Professions 13, no. 3 (1993): 215–20. http://dx.doi.org/10.1002/chp.4750130304.

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Adelson, Richard, Wendy J. Vanloy, and Kenneth Hepburn. "Performance change in an organizational setting: A conceptual model." Journal of Continuing Education in the Health Professions 17, no. 2 (1997): 69–80. http://dx.doi.org/10.1002/chp.4750170201.

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Fedotov, A., G. Vagapov, L. Grackova, and R. Abdullazyanov. "Rated Power Determination for Autonomous Micro Combined Heat and Power and Rechargeable Battery System." Latvian Journal of Physics and Technical Sciences 57, no. 6 (December 1, 2020): 12–22. http://dx.doi.org/10.2478/lpts-2020-0030.

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AbstractAn autonomous micro combined heat and power (Micro-CHP) is usually installed to increase energy efficiency and reduce energy costs in areas remote from large power systems. The main goal of autonomous Micro-CHP is to provide residential and industrial areas with electricity and heat. By designing an autonomous Micro-CHP, one of the key issues is the determination of rated power, since the energy efficiency of equipment and the costs of fossil fuels depend on the rated power. The mathematical model can better calculate the necessary rated power for an autonomous Micro-CHP in the case of operation with rechargeable batteries. Overall, the results have shown that the engine characteristics, operation process of three-phase synchronous generator and statistical information on loads are the criteria for improving energy efficiency.

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Zhang, Ruoyu, Haichao Wang, Xiaozhou Wu, Xiangli Li, and Lin Duanmu. "The application of the TES technology in CHP heating system with Chinese demand profiles——A techno-economic feasibility case study." E3S Web of Conferences 111 (2019): 06010. http://dx.doi.org/10.1051/e3sconf/201911106010.

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The thermal energy storage (TES) technology is an effective method to enhance the planning and the economy of the combined heat and power (CHP) plants, while it has still not been broadly promoted in China. In this paper we firstly establish a mathematical model for a Chinese CHP plant with TES. Then the EnergyPRO software is used to find the optimum type of the TES tank in a three-tariff electricity pricing market and the operation strategy of the CHP plant with the selected TES tank is studied. Thirdly, the economic benefits of the system with/without TES is evaluated. The results show that adding a TES tank with volume of 24000m3 can significantly increase operational profits of the CHP system and reduce the use of peak-shaving heat source.

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Davoodi, Elnaz, Salar Balaei-Sani, Behnam Mohammadi-Ivatloo, and Mehdi Abapour. "Flexible Continuous-Time Modeling for Multi-Objective Day-Ahead Scheduling of CHP Units." Sustainability 13, no. 9 (April 30, 2021): 5058. http://dx.doi.org/10.3390/su13095058.

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Increasing applications of CHP units have turned the problem of finding the best optimization model into a significant subject for scholars. In this respect, this paper is aimed at driving a novel formulation to the multi-objective day-ahead scheduling of CHP units using Bernstein polynomials, which more optimally schedules power and heat generations as well as ramping trajectories. This procedure includes yielding an affine function that closely approximates real-time net-load and generation trajectories, which is demonstrated to have a superior performance to the conventional hourly day-ahead scheduling of CHP units based on discrete-time approximation. The problem of how to handle various objective functions by function space method is also addressed. The simulations conducted on the sample test systems, which consist of CHP systems, thermal and heat-only units, as well as thermal and electrical loads, show that the suggested multi-objective model can perfectly cover the total heat and electrical loads in terms of economic and environmental criteria. More importantly, the results indicate that the accuracy of the proposed approach renders cost saving of 1.67% and emission saving of 1.46% in comparison with the conventional hourly-based model, apart from leading to fewer ramping scarcities in real-time operations.

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Perikova, E. I., and V. M. Byzova. "Factor Structure of the Russian Version of the «Metacognitive Awareness Inventory»." Cultural-Historical Psychology 18, no. 2 (2022): 116–26. http://dx.doi.org/10.17759/chp.2022180213.

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Metacognitive processes are important for the success in the wide range of educational activities of youth and young adults. However, the positive correlations between metacognition and academic achievements are not high enough, and the instruments used in these studies might be the reason. We explored the factor structure of the Russian version of the questionnaire “Metacognitive Awareness Inventory” developed by G. Schraw and R. Dennison and adapted by A.V. Karpov and I.M. Skityaeva into Russian. The participants of our study were 527 residents of St. Petersburg, which were studying at the university at the time. Among them there were 366 students getting their first diploma and 161students getting their second diploma (average age 23.8 ± 8.8). In this article the authors present the results of a confirmatory factor analysis of four models, which are the most frequently used in foreign and Russian literature: unidimensional model; two different two-factor models; eight-factor model. Evaluation of the model fit indices for the four models showed that none of them were a god fit. We reduced the number of items of the questionnaire and re-implemented the factor analysis of these four models. The values of indicators of a good model fit improved. In the short version of the questionnaire “Metacognitive Awareness Inventory” the authors discovered two scales – knowledge of cognition and regulation of cognition, which included 8 subscales: declarative knowledge, procedural knowledge, conditional knowledge, planning, information management strategies, comprehension monitoring, debugging strategies, evaluation.

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Nagatomo, Daiki, Madoka Taniai, Harumi Ariyasu, Mutsuko Taniguchi, Miho Aga, Toshio Ariyasu, Tsunetaka Ohta, and Shigeharu Fukuda. "Cholesteryl Pullulan Encapsulated TNF-αNanoparticles Are an Effective Mucosal Vaccine Adjuvant against Influenza Virus." BioMed Research International 2015 (2015): 1–15. http://dx.doi.org/10.1155/2015/471468.

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We encapsulated tumor necrosis factor-α(TNF-α), a major proinflammatory cytokine, into cholesteryl pullulan (CHP) to prepare TNF/CHP nanoparticles. In this report, we describe the immune-enhancing capability of the nanoparticles to act as a vaccine adjuvant. TNF/CHP nanoparticles showed excellent storage stability and enhanced host immune responses to external immunogens. The nanoparticles were effective via the nasal route of administration for inducing systemic IgG1as well as mucosal IgA. We applied the nanoparticles in a model experimental influenza virus infection to investigate their adjuvant ability. TNF/CHP nanoparticles combined with a conventional split vaccine protected mice via nasal administration against a lethal challenge of A/PR/8/34 (H1N1) influenza virus. Mechanistic studies showed that the nanoparticles enhanced antigen uptake by dendritic cells (DCs) and moderately induced the expression of inflammation-related genes in nasopharynx lymphoid tissue (NALT), leading to the activation of both B and T cells. Preliminary safety study revealed no severe toxicity to TNF/CHP nanoparticles. Slight-to-moderate influences in nasal mucosa were observed only in the repeated administration and they seemed to be reversible. Our data show that TNF/CHP nanoparticles effectively enhance both humoral and cellular immunity and could be a potential adjuvant for vaccines against infectious diseases, especially in the mucosa.

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Journal articles on the topic 'CHP model'

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