Theoretical Impact of Building Façade Thickness on Daylight Metrics and Lighting Energy Demand in Buildings: A Case Study of the Tropics

In daylighting design, variation of building façade thickness (f) will result in variation of the daylight opening areas, which in turn will modify the values of daylight metrics within the space. However, studies dedicated to investigating the impact of varying f on indoor daylight metrics are relatively scarce. This study, therefore, aims to assess the theoretical impact of various façade thicknesses on various daylight metrics and lighting energy demands in a reference office space. Analytical calculations are performed using an outdoor diffuse illuminance profile of a tropical city. The building façade thickness values are varied within 0–0.50 m, at window-to-wall ratios (WWR) of 25%, 50%, and 75%. Based on sensitivity analysis, it is found that variation of f yields different impacts on the observed metrics, with sDA300/50% being the least influenced. Among all metrics in the central calculation point, DA300, UDI-a, and UDI-a′ yield relatively small coefficients of variation, and thus, have the lowest uncertainty with respect to f. Among all metrics for the entire room, sDA300/50% and sUDI-a50% have the lowest uncertainty, with interquartile ranges of no more than 0.4%. Overall, the contribution of this study is providing insight into the impact of façade thickness on various daylight metrics in indoor spaces, particularly in the worst-case scenario under the standard CIE overcast sky.

Clearinghouses Versus Central Counterparties From Margin Calculation Point Of View

Clearinghouses and central counterparties (CCPs) have a notable role in financial markets, namely facilitating securities trading and derivative transactions on exchanges and over-the-counter markets. They have to clear the transactions and carry out their settlements to decrease costs and settlement risk. To efficiently carry out this activity, they need to collect adequate collateral from the trading parties as guarantees. Two main elements of these guarantees are the margin requirement and default fund contribution. Our paper focuses on the margin calculations and emphasizes their notable difference in the case of clearinghouses and CCPs. Our main result is that clearinghouses’ margin requirement is better from a procyclicality point of view; however, CCP margining is more prudent based on our results.

Kinematic characteristics of the car movement from the top to the calculation point of the marshalling hump

Introduce analytical acceleration formulas that are derived from the classic d'Alembert principle of theoretical mechanics for high-speed sections and sections of retarder positions; show the possibility of determining the instantaneous car speeds in each section of the marshalling hump according to the formulas of elementary physics both for high-speed sections and for sections of retarder positions; provide formulas for determining the time of movement of a car with uniformly accelerated and/or uniformly retarded motion of the car on the inclined part of the hump, as well as in areas of retarder positions. Research methods: The classic d'Alembert principle of theoretical mechanics is widely used in the paper. Main results: For the first time, the results of constructing a graphical dependence of the estimated height of the marshalling hump over the entire length of its profile are presented in the form of a decrease in the profile height of each section of the inclined part in proportion to the slope of the track. The results of constructing graphical dependences on changes in the speed and time of movement of a car along the entire length of the inclined part of the marshalling hump are fundamentally different from the existing methodology, where, for example, curves of medium (rather than instantaneous) speeds of a car are built. The proposed new methodology for calculating the kinematic characteristics of the car movement along the entire length of the hump allows an analysis of the mode of shunting car at the marshalling humps.

Thermodynamics Cycle of Gas-Cooled Fast Reactor

This paper deals with the thermo-hydraulic aspect of gas cooled fast 4 generation reactor. The paper is focused on the comparison of direct and indirect strategy of thermodynamics cycle of helium cooled reactor from the thermodynamics and turbomachinary point of view. The analyses respect pressure looses at all major part of the equipment - reactor, heat exchanger, pipe lines, etc. The compressor and gas turbines efficiency are includes in calculation as well. The working fluid in primary circuit is helium. In the secondary circuit a mixture of helium and nitrogen is considered. The Cycle characteristic point and efficiency calculation reflects mixture properties of the real gas. Calculation point out the influence of mixture composition on the basic structural parameters of the turbines, compressor and heat exchangers. Thermodynamics cycle efficiency, specific heat input/output, heat flux and cycle work will be presented as characteristic parameters.

Influence of Interlink Topology on Multilayer Network Robustness

Cascading failures between interdependent multilayer networks are being widely studied, especially the trend of robustness caused by the interlinks between networks. However, few researchers pay attention to the effect of the interlink topology on the robustness of coupled networks, which is a critical interlink factor of multilayer networks. In this study, the method frame of multilayer network experiment simulation is given. Through numerical simulation and actual network simulation, the exhaustive method is used to enumerate all the patterns of interlink topological relations of multilayer networks (three-layer or more). The research verifies that the interlink topology affects the global robustness and that there exists a fragile interlink pattern in the patterns of interlink topologies. The star-like interlink pattern with the most uneven interlink-degree distribution leads to the weakest robustness; the pattern with average interlink-degree distribution reveals good global stability as a loop-like pattern or entire interlink pattern. In addition, the influence of interlink topology is independent. The simulation results are not affected by the network layer number and intraparameters (including the network-generated form, each layer of network node number, and average degree of each layer of network). Thus, ignoring the interlink topology may result in the actual system suddenly becoming vulnerable before the theoretical calculation point. Interlink topology as an independent factor affecting the robustness of multilayer networks should be paid more attention.

Improving Solar Potential Map: Ditching Net-Metering, Embracing Demand Curve and Local Weather

The research expands the bottom-up approach to determine investment cost for self-sufficient Solar Plus systems. Existing solar maps usually utilize net-metering scheme and treat electricity grid as giant battery. However, with increased solar production, this might put an additional strain to the grid. In addition, to obtain national wide results, multiple weather patterns obtained from different meteorological stations were analyzed which also resulted in different demand curves. The scope of the research was therefore largely increased by calculating all available meteorological data in form of a typical year for Slovenia, which consist of 23 data points evenly spread all over Slovenia. However, those points vary quite a bit – some stations are positioned in the cities and towns, while others are located in small villages or places of interests (i.e., mountain resorts or airports). The points also vary in altitude (from few meters to over 2500 m) and cover different climate zones. The majority of Slovenia lies in continental zone (described with Dfb and Dfb by Köppen-Geiger climate classification) with cold winters and warm summers, with some subtropical climate at the coastal areas (Cfa and Cfb). Some mountain areas have tundra climate (ET). The presented research shows how to combine the existing data to calculate optimal Solar Plus instalment for self-sufficient buildings for each calculation point. The already validated simplified model was used for calculation of energy balance for the typical year which was later used for optimization of the results regarding costs. This includes the roof area for photovoltaic, optimal orientation of solar panels, the capacity of the battery storage and other influential parameters. The results clearly indicated the capability of each analyzed area for Solar Plus installation.

Study of acoustic characteristics of noise barriers

The acoustic efficiency of noise barriers has been studied using the developed two-dimensional finite element model in the COMSOL Multiphysics software package. Numerical calculations of the semi-infinite barrier efficiency have been compared with calculations conducted by the Maekawa formula. The main attention has been paid to the influence of the underlying surface on barrier acoustic characteristics. The barrier acoustic efficiency depends on its height, the position of the noise source and on the calculation point above the underlying surface. This dependence has been presented in this research.

Overdispersed-Poisson Model in Claims Reserving: Closed Tool for One-Year Volatility in GLM Framework

The aim of this paper is to carry out a closed tool to estimate the one-year volatility of the claims reserve, calculated through the generalized linear models (GLM), notably the overdispersed- Poisson model. Up to now, this one-year volatility has been estimated through the well-known bootstrap methodology that demands the use of the Monte Carlo method with a re-reserving technique. Nonetheless, this method is time consuming under the calculation point of view; therefore, approximation techniques are often used in practice, such as an emergence pattern based on the link between the one-year volatility—resulting from the Merz–Wüthrich method—and the ultimate volatility—resulting from the Mack method.

The use of NRCS synthetic unit hydrograph and Wackermann conceptual model in the simulation of a flood wave in an uncontrolled catchment/ Zastosowanie syntetycznego hydrogramu jednostkowego NRCS oraz konceptualnego modelu Wackermana do symulacji fali wezbraniowej w zlewni niekontrolowanej

The paper presents the results of using two models: a conceptual model of Wackermann and a NRCS-UH synthetic unit hydrograph, for flow calculation in uncontrolled catchment of the Słonka, Poland. These models were chosen because of simplicity of models’ parameters evaluation, what is important from engineering calculation point of view. Flows with the probability of exceed amounting to 0.5%, 1%, 2%, 5%, 10%, 20%, and 50% and for different levels of the catchment moisture were evaluated. The flood waves generated in the Wackermann model were characterized by a short duration (over 2 hours), shorter concentration time (about 1 hour), and by about 70% higher peak flow values than those generated using the NRCS-UH method. A common feature of both methods were higher values of peak flows for the third level of the catchment moisture, as compared to the second level. It is also worth noticing that in both methods no flood wave was generated for the probabilities of 10, 20 and 50% and for the second level of the catchment moisture. It was assumed that hydrographs made with use Wackermann model better describe flood wave in mountain river, which Słonka is.