A MILP algorithm for the optimal sizing of an off-grid hybrid renewable energy system in South Tyrol

The exploitation of renewable energy sources through sustainable energy technologies are taking the field to decrease the pollutions' emissions into the Earth's environment. To offset the limitations of such resources, hybrid energy systems are becoming fundamental in grid-connected applications as well as in off-grid ones. However, the unsteady behavior of renewable sources, such as Sun and Wind, complicates the prediction of the energy production's trend. The main factors and components involved in the design of hybrid energy systems are: (i) type of generators, (ii) their optimal number, (iii) storage systems and (iv) optimal management strategies. All of them have to be considered simultaneously to develop the optimal solution aimed at either reducing the dependence from fossil fuels or granting the supply of energy. In this paper, a methodology based on the Mixed Integer Linear Programming (MILP) is presented and adopted to meet the electric demand of a mountain lodge located in a remote area in South-Tyrol (Italy). The methodology has been developed implementing an algorithm through the Matlab ©software. The algorithm is capable of evaluating the optimal size of a hybrid off-grid Solar–Wind system with battery storage in order to replace an Internal Combustion Engine (ICE) fueled by diesel. Keywords: Hybrid off-grid energy system, Mixed integer linear programming, Matlab©, Optimization algorithm, Renewable energ

The Role of <i>kunten</i> Materials in the Process of Sino-Japanese Hybridization

The history of the Japanese written language can be seen as a main frame of different registers of the native language – buntai 文体 – intersecting at various levels with a foreign one, namely classical Chinese. Although these diatypes are different, they are all part of the same lexico-syntactic repertoire shared by the community and whose use is determined by context. Hence, the type of code in use depends on the field and purpose of the message. In recent years the field has been enriched by a number of thought-provoking theories. However, buntai studies still constitute a complex and intricate discipline within which numerous questions remain to be answered. This paper will a) provide a review of existing scholarship on the role played by kunten materials in defining the formation process of Sino-Japanese hybrid writing – wakan konkōbun; b) outline, for the first time, the main differences between the two most controversial forms of written language, Japanized written Chinese – waka kanbun – and Sino-Japanese hybrid writing, and redefine their role within the history of the Japanese written language; c) survey textual evidence to show how an embryonic form of Sino-Japanese hybrid writing existed before the twelfth century, proving that the evolution of wakan konkōbun is not directly linked to the formation of middle Japanese

The Role of kunten Materials in the Process of Sino-Japanese Hybridization

The history of the Japanese written language can be seen as a main frame of different registers of the native language – buntai 文体 – intersecting at various levels with a foreign one, namely classical Chinese. Although these diatypes are different, they are all part of the same lexico-syntactic repertoire shared by the community and whose use is determined by context. Hence, the type of code in use depends on the field and purpose of the message. In recent years the field has been enriched by a number of thought-provoking theories. However, buntai studies still constitute a complex and intricate discipline within which numerous questions remain to be answered. This paper will a) provide a review of existing scholarship on the role played by kunten materials in defining the formation process of Sino-Japanese hybrid writing – wakan konkōbun; b) outline, for the first time, the main differences between the two most controversial forms of written language, Japanized written Chinese – waka kanbun – and Sino-Japanese hybrid writing, and redefine their role within the history of the Japanese written language; c) survey textual evidence to show how an embryonic form of Sino-Japanese hybrid writing existed before the twelfth century, proving that the evolution of wakan konkōbun is not directly linked to the formation of middle Japanese

Unit commitment optimization of a micro-grid with a MILP algorithm: Role of the emissions, bio-fuels and power generation technology

Abstract Management strategies of complex energy systems composed by different technologies is mandatory to exploit optimally the characteristics of each power generator, to reduce the cost of energy, the impact of greenhouse gases emissions and to increase the penetration of mini- and micro-grids into energy systems. To this purpose, optimization methods and algorithms have to be developed to assess the unit commitment of generators and to suggest decision variables in the definition of the emission costs. In this paper, a novel Mixed Integer Linear Programming (MILP) optimization algorithm has been developed to compute the optimal management of a micro-energy grid composed either by four Internal Combustion Generators (ICGs), or three ICGs and a Micro Gas Turbine (MGT). The algorithm optimizes a multi objective function that takes in consideration the total cost, the NO x and the CO2 emissions of the system, while setting some technological constraints, like start-ups and transients that are typically neglected. Moreover, different fuelling of the devices is evaluated. The model proved the importance of including an accurate model of the greenhouse gases emissions as they can significantly affect the optimization results. Furthermore, it proved to be very flexible and to be a proper basis to be adopted in more complex systems embedding energy storage devices and renewable energy systems

Study of a Pump-as-Turbine (PaT) speed control for a Water Distribution Network (WDN) in South-Tyrol subjected to high variable water flow rates

Abstract The development of renewable energy technologies for producing clean energy has more and more become a priority worldwide. Research activities have not just to target the technological improvement of such systems, but they have also to consider their market deployment. In such a scenario, hydraulic machines, in particular Pumps-as-Turbines (PaTs), can play a key role in energy recovery applications. One of the main open issues of PaTs is the performance forecast in turbine mode, due to the lack of data from manufacturers, and their use in some applications with high flow rate and pressure variability, especially at part-load operating conditions like in energy recovery applications within Water Distribution Networks (WDNs). In this work, a MATLAB® Simulink model is developed for simulating a branch of the WDN located in Laives (South-Tyrol), where specific PaTs have been selected and used to substitute Pressure Reducing Valves (PRVs). A speed control by means of an inverter is performed due to the high variability of the flow rate inside the grid branch, allowing the machines to operate at their Best Efficiency Point (BEP). A preliminary analysis showed that it is possible to increase the energy production of about 23% with respect to a constant-speed machine, leading to a significant decrease of the PayBack Period (PBP)

oral hpv infection and persistence in patients with head and neck cancer

ObjectiveTo investigate the presence and persistence of human papillomavirus (HPV) infection in the oral mucosa of patients with head and neck squamous cell carcinoma (HNSCC), and its correlation with prognosis.Study designHPV infection was characterized in tumors and pre and posttreatment oral scrapings in 51 patients with HNSCC and matched controls using the SPF10 LiPA Extra assay. p16INK4A immunostain and in situ hybridization for high-risk HPV genotypes recognized transcriptionally active infection in tumor samples. The risk of infection was compared in patients and controls. The association of pretreatment HPV status with recurrence and survival and with posttreatment HPV persistence was assessed.ResultsOral HPV infection risk was significantly higher in patients with HNSCC than in controls (P < .001). Oral HPV infection was associated with infection in the first posttreatment scrapings (P = .015), but did not affect recurrence or prognosis.ConclusionOral HPV infection is frequent in patients with HNSCC and has no prognostic implications, suggesting that posttreatment polymerase chain reaction monitoring on oral cells is not effective to monitor patient recurrence risk

Kif13b Regulates PNS and CNS Myelination Through the Dlg1 Scaffold

Microtubule-based kinesin motors have many cellular functions, including the transport of a variety of cargos. However, unconventional roles have recently emerged, and kinesins have also been reported to act as scaffolding proteins and signaling molecules. In this work, we further extend the notion of unconventional functions for kinesin motor proteins, and we propose that Kif13b kinesin acts as a signaling molecule regulating peripheral nervous system (PNS) and central nervous system (CNS) myelination. In this process, positive and negative signals must be tightly coordinated in time and space to orchestrate myelin biogenesis. Here, we report that in Schwann cells Kif13b positively regulates myelination by promoting p38γ mitogen-activated protein kinase (MAPK)-mediated phosphorylation and ubiquitination of Discs large 1 (Dlg1), a known brake on myelination, which downregulates the phosphatidylinositol 3-kinase (PI3K)/v-AKT murine thymoma viral oncogene homolog (AKT) pathway. Interestingly, Kif13b also negatively regulates Dlg1 stability in oligodendrocytes, in which Dlg1, in contrast to Schwann cells, enhances AKT activation and promotes myelination. Thus, our data indicate that Kif13b is a negative regulator of CNS myelination. In summary, we propose a novel function for the Kif13b kinesin in glial cells as a key component of the PI3K/AKT signaling pathway, which controls myelination in both PNS and CNS

Speed and Pressure Controls of Pumps-as-Turbines Installed in Branch of Water-Distribution Network Subjected to Highly Variable Flow Rates

The use of Pumps-as-Turbines (PaTs) to replace hydraulic turbines as energy-recovery units in industrial and civil applications is widening the penetration of hydropower in small-scale plants. PaTs show advantages in terms of installation costs and the availability of solutions. Water Distribution Networks (WDNs) represent a potential application where PaTs can be installed to recover water-pressure energy. In this work, a MATLAB&copy;&ndash;Simulink model of a WDN branch located in South-Tyrol (Italy) was developed. The flow rate of the WDN was assessed though a measurement campaign showing high daily variability, which negatively affect PaT performance. To let the machine operate close to the Best Efficiency Point (BEP), four different operating strategies were studied to meet the constraint of a fixed pressure equal to 4 bar downstream the WDN branch, required to supply water to users. A PaT speed control strategy was implemented, granting better exploitation of flow rates even in the presence of high daily fluctuations. Energy recovery was 23% higher than that of the reference thanks to an advanced strategy based on controlling PaT rotational speed when the flow rate is smaller than that of the design, and operating in off-design conditions when flow rate is higher than that of the BEP

Comparison of Batteries and Pumping Hydro with PaTs as energy storage technologies for a micro-hybrid generation system: Multi-objective optimization through a MILP algorithm

Small-scale hybrid energy systems are often composed by different power production technologies and adopted in mini-grids. In this work, a Mixed Integer Linear Programming optimization algorithm has been developed to compute the optimal scheduling of a micro-grid constituted by Internal Combustion Generators (ICGs) and a Storage System that can be either a conventional battery storage system or a Pumping Hydro energy Storage (PHES) based on Pump-as-Turbines. The algorithm computes the optimal energy generation scheduling of the micro-grid, minimizing a multi-objective fitness function constituted by the total costs of the energy system and the total CO2 and NOx emissions. In particular, the emissions are modelled with varying trends depending on the ICG load and not with constant values, which represents a simplification that is often adopted but that can induce misleading results. Furthermore, the algorithm takes into account all the physical constraints related to the generators and the storage system, such as maximum and minimum power generation, ramp-up and ramp-down limits and minimum up and down-time. The two energy storage technologies are compared and results show that a management strategy based on this algorithm can reduce significantly the total emissions of the system