Miracle-dz/UniFAR-FTUs huggingface dataset:
Reliability Evaluation in Seismic Design: A Response Surface Methodology

Performance-based seismic design requires consideration of the uncertainties in corresponding demands and capacities. A response surface methodology is used to evaluate the annual exceedance probability in each specified, damage-related performance level. The nonlinear dynamic response of the structure to the seismic action is studied considering, among the uncertainties, the peak acceleration and the frequency content of the ground motion. Advantages and disadvantages of two types of response surface formulations are discussed, including two ways of considering dispersion produced by different ground motions. The procedure is illustrated with two examples: an elevated water tank and a five-story portal frame. Finally, the method is applied to the calibration of a deterministic, factored design code approach with multiple performance objectives.
A Review and Classification of Most Used MPPT Algorithms for Photovoltaic Systems

Energy has become an indispensable need to sustain our lives. Approximately 80% of the energy consumed in the world is produced from fossil sources. For the reasons such as the depletion of fossil resources and their damages to the environment, the interest in renewable resources is increasing and the importance of solar systems, which draws attention with unlimited energy resource, is increasing day by day. The biggest disadvantages of solar systems are seen as low production efficiency and high setup cost. A PV cell can convert only 5-20% of the solar energy coming on it to electricity. Based on this, it is very important to provide the power obtained from PV with maximum efficiency and minimum cost. Accordingly, many different maximum power point tracking (MPPT) algorithms have been proposed over the years. Although the purpose of all proposed algorithms is the same, they have many advantages and disadvantages compared to each other. In this study, the most used MPPT algorithms have been examined and compared by considering many parameters such as tracking speed, stability, and cost etc. and a new classification of these algorithms is proposed.
A new PWM pattern generation method for a PWM converter applied to a superconducting magnet

This paper presents a new algorithm for pulse-width modulation (PWM) pattern generation for three-phase current-source converters. Since switching devices of the converters require a minimum conducting duration to ensure current commutation, it is difficult to keep stably their output voltage close to zero for the converters using the conventional methods of PWM pattern generation. We propose a new PWM pattern generation method that can realize the zero output voltage perfectly without any restrictions on the conducting duration of the switching devices by optimizing the arrangement of the pulse patterns. The performance of this new algorithm is demonstrated by the numerical simulation using PSCAD/EMTDC. This method is applicable to a PWM converter of the superconducting magnet power supply, because it can maintain the coil current constant stably by keeping the output voltage zero and change its operation mode between rectification and inversion without additional complicated controls.
Business Roadmap Model: A Review of Research

In doing business, business actors must understand the importance of a business model in entrepreneurship; a business strategy is needed. There are several business models, but the one most often used by business actors is the Business Model Canvas or what we usually know (BMC). According to several studies, the Business Model Canvas is a business model that can still be developed into a more detailed business model and better mapping. Then from the Business Model Canvas, a new business model was developed, namely the Business Road Map, to win the market competition. Business Road Map is a pattern or Business Mapping Method to build a business model/business plan capable of creating growth over time.
Mechanism and growth rate of underfill delaminations in flip chips

Delamination of underfill in flip chips is a widely accepted major cause for failure. However, there is a lack of information on the mechanism of this effect. A novel methodology is used to examine these delaminations in this paper. Instead of the expensive and time-consuming scanning acoustic microscopy with limited resolution, an optical method is established. For that the silicon chip was replaced by a glass chip (Pyrex). With usual passivations, the component is comparable to silicon flip chips from the mechanical point of view. This gives the possibility to look at the interface underfill/passivation or underfill/PCB by a microscope and a CCD camera. Photo analysis software allows to quantify delaminated versus not delaminated regions. Hence, an evaluational method for material and geometric impacts to delaminations is available. The effect of the following parameters were observed: chip size, bump height, substrate thickness; passivation, underfill material; flux material, die sites with and without solder resist. Beside other results, it has been shown, that the most reliable combination was made of 0.8 mm substrate, a passivation of SiO/sub 2/ and no use of solder resist. A good meniscus could improve the hydro-thermal fatigue. As a function of geometric parameters different behavior of crack growth were found.
Task Interference in Prospective Memory: Adopting a Retrieval Mode and Checking for Targets

Embedding a prospective memory task in an ongoing activity can interfere with performance of that ongoing activity. One explanation of this task interference is that it entails (a) adopting a retrieval mode or readiness to encounter the targets that indicate when to perform the intended action and (b) checking the environment for those targets. An experiment using a new method is reported and provides evidence for these processes. On control trials, participants performed just the ongoing activity (a short-term memory task combined with a 4-choice RT task). On experimental trials, a prospective memory task (press the Enter key if certain words appear in the short-term memory task) was embedded in the ongoing activity. Evidence for adopting a retrieval mode came from finding slower RT task performance on control trials when participants had already been instructed about the prospective memory task than when they had not yet been so instructed. Evidence for target checking came from finding slower RT task performance on experimental trials when a target could appear in any one of five locations than in just one location
The Role of University-Based Incubators in Social Entrepreneurship’s Development: The Capability Approach as an Evaluative Framework

Introduction/Main Objectives: This study evaluates the role of a large university in developing the social entrepreneurship capabilities of its students and fresh graduates through its business incubator; and investigates why tenants choose to be or not to be social entrepreneurs after their incubation process. Background Problems: There are many discussions about university-based incubators for developing entrepreneurship, but the actual mechanism of how these incubators develop social entrepreneurs is still unknown. Novelty: This research explores the development of social entrepreneurship through the university-based incubator program. Hence, it can be used to provide best practices for the program, especially for developing the tenants’ capacity. Research Methods: This study applies a case study approach and adopts Amartya Sen’s capability approach as an evaluative framework. The C-Hub UGM was chosen as a case since it was selected as a good example of a social entrepreneurship incubator by the British Council. This research used three sources of evidence: documents, interviews, and focus group discussions to collect information from 14 of the incubator’s tenants. Finding/Results: The results reveal that the incubator serves as a hub for the resources that enhance the tenants’ personal conversion factors and their performance as agents for change. Subsequently, the incubator improves the tenants’ social entrepreneurship capabilities set; however, it is up to the tenants to choose whether they want to continue as social entrepreneurs or work in other roles as their functioning. Conclusion: This study illuminates the linkages among the concepts of the capability approach, the university-based incubator and social entrepreneurship. It reveals that the university-based incubator serves as a hub for the resources that enhance the tenants’ personal conversion factors; thereby they can be effective social entrepreneurs.
Aperture-coupled patch antenna on UC-PBG substrate

The recently developed uniplanar compact photonic bandgap (UC-PBG) substrate is successfully used to reduce surface-wave losses for an aperture-coupled fed patch antenna on a thick high dielectric-constant substrate. The surface-wave dispersion diagram of the UC-PBG substrate has been numerically computed for two different substrate thickness (25 and 50 mil) and found to have a complete stopband in the frequency range of 10.9-13.5 and 11.4-12.8 GHz, respectively. The thicker substrate is then used to enhance broadside gain of a patch antenna working in the stopband at 12 GHz. Computed results and measured data show that, due to effective surface-wave suppression, the antenna mounted on the UC-PBG substrate has over 3-dB higher gain in the broadside direction than the same antenna etched on a grounded dielectric slab with same thickness and dielectric constant. Cross-polarization level remains 13 dB down the co-polar component level for both E- and H-planes.
Characterization of bipolar snapback and breakdown voltage in thin-film SOI transistors by two-dimensional simulation

A two-dimensional finite-difference simulator for silicon-on-insulator (SOI) MOSFETs is presented. The simulator is derived from the MINIMOS4 simulator and incorporates additional features which permit the characterization of the bipolar snapback effect, which has been observed as a limiting feature in ultra-thin-film transistors. The snapback effect is illustrated as a hysteresis mechanism whereby, for a given bias condition, there are two different solutions to the semiconductor equations, depending on the starting condition. Examples of the application of the simulator to predict breakdown voltage in submicrometer devices are considered. Excellent agreement with measured values of breakdown voltage has been achieved for submicrometer n-channel transistors, both with and without the use of lightly doped drains. >
Evaluation of 5500 V-class SI-thyristor as pulsed power switching device utilizing a low inductance testing circuit

Characterization of 5500 V-class reverse conducting SI-thyristors as a pulsed power switching device was examined utilizing a low inductance testing circuit. The testing circuit consisted of nineteen doorknob type ceramic capacitors with the total capacitance of 38 nF, and had a residual inductance of less than 13 nH. The SI-thyristor, tested in this report, was specially designed for pulsed power applications. When the anode voltage of 5 kV was applied, a discharge current rose up to 4.2 kA with dl/dt of 6.8/spl times/10/sup 10/ A/s, and the anode voltage fall time reached 62 ns. The comparison with conventionally designed SI-thyristors indicated the effectiveness of the new design.
Properties and evolution of a submesoscale cyclonic spiral

Abstract. The evolution of a submesoscale cyclonic spiral of 1 km in diameter is simulated with ROMS (Regional Ocean Modeling System) using 33.3 m horizontal resolution in a triple-nested configuration. The generation of the spiral starts from a dense filament that is rolled into a vortex and detaches from the filament. During spin-up, extreme values are attained by various quantities, that are organized in single-arm and multi-arm spirals. The spin-down starts when the cyclone separates from the filament. At the same time, the horizontal speed develops a dipole-like pattern and isotachs form closed contours around the vortex center. The amplitudes of most quantities decrease significantly, but the instantaneous vertical velocity w exhibits high-frequency oscillations and more pronounced extremes than during spin-up. The oscillations are due to vortex Rossby waves (VRWs), that circle the eddy counterclockwise and generate multi-arm spirals with alternating signs by means of azimuthal vorticity advection. Experiments with virtual surface drifters and isopycnal floats indicate downwelling everywhere near the surface. The downwelling is most intense in the center of the spiral at all depth levels, leading to a radial outflow in the thermocline and weak upwelling at the periphery. This overturning circulation is driven by convergent near-surface flow and associated subduction of isopycnals. While the downwelling in the center may support the export of particulate organic carbon from the mixed layer into the main thermocline, the upwelling at the periphery effectuates an upward isopycnal transport of nutrients, enhancing the growth of phytoplankton in the euphotic zone.
Comparative performance analysis of a flexible manufacturing system (FMS): a review-period-based control

The flexibility of a flexible manufacturing system (FMS) has provided it with the capability to become one of the most suitable manufacturing systems in the present manufacturing environment of customized and an increasing variety of products with shorter life cycles. Significant research has been made on flexibility from different points of views. The paper focuses on the study of flexibility in FMS from the view of a decision-and-information system. In modelling flexibility and other physical and operational parameters of an FMS, researchers have mostly assumed a decision-and-information system has the capability of real-time control. The literature reports qualitatively that real-time control may be difficult to achieve and justify economically. The paper presents a comparative study of an FMS operating under real-time control, review-period-based control and reactive control. It also focuses on the comparative performances of the key parameters such as routing flexibility and control strategies of an FMS operating under these different modes of a decision-and-information system. It contributes an approach using simulation under Taguchi's method to study the various factors contributing to FMS performance and identifies the critical parameters for improving performance. The result shows that review-period-based control can be effectively implemented in an FMS with a lower flexibility level. Smaller review-period size can perform comparable with real-time control. The decision-maker must ensure the FMS's capability of having real-time control, otherwise it may result in a reactive control that may considerably deteriorate the performance. The results under Taguchi's method indicate that the routing flexibility and control strategy should have maximum relative percentage contributions in the performance of an FMS, while the decision-and-information system should have the minimum. Increasing the relative percentage contribution of a decision-and-information system may deteriorate the performance of a given FMS.
Optimum Network Var Planning by Nonlinear Programming

Controllable network VAr compensators are required in high voltage transmission networks for system loss reduction and voltage maintenance during normal and emergency operation. Long term planning of network compensators is generally based on contingencies which cause the system voltage to move out of the desired operational range. A non-linear analysis based on multi-contingency states is presented for optimum network VAr planning. The proposed approach is critically evaluated and compared with the existing techniques and is illustrated by an application to a high voltage model system.
Assessing the Sustainability of Thryonomys swinderianus Hunting in Ogoni Land

Background: Thryonomys swinderianus is a renewable natural resource and is a major mammal that constitute what is termed bushmeat in Ogoni land. Between July 2017 and June 2018, 10320Kg of Thryonomys swinderianus meat or 2580 animals were obtained from the wild by hunting. The number of animals removed compared to its population as at June 2017 prompted this study. Aim: The aim of the study is to ascertain the sustainability of this level of harvest in Ogoni land. Methods: The Robinson and Redford model of 1991 was used to assess the sustainability of this harvest in this study. The maximum possible production of Thryonomys swinderianus from July 2017 to June 2018 was 3.5/Km² and the proportion of this production to be harvested sustainably is 2.1/Km² or 8.4Kg/Km². The actual harvest within this period was 2.58/Km² or 10.32Kg/Km². Results: The actual harvest of 2.58/Km² is greater than the maximum sustainable yield of 2.1/Km² and as such, the harvest of 2.58 Thryonomys swinderianus per square kilometer per year is not sustainable in Ogoni land. Conclusion: The unsustainable harvest of Thryonomys swinderianus should as a matter of urgent concern be monitored and regulated. Continuation of this rate of removal will diminish the renewal rate and lead to the extinction of Thryonomys swinderianus in the near future.
Real time monitoring of petroleum leakage detection using etched fiber Bragg grating

Detection of petroleum leakages in pipelines and storage tanks is a very important as it may lead to significant pollution of the environment, accidental hazards, and also it is a very important fuel resource. Petroleum leakage detection sensor based on fiber optics was fabricated by etching the fiber Bragg grating (FBG) to a region where the total internal reflection is affected. The experiment shows that the reflected Bragg’s wavelength and intensity goes to zero when etched FBG is in air and recovers Bragg’s wavelength and intensity when it is comes in contact with petroleum or any external fluid. This acts as high sensitive, fast response fluid optical switch in liquid level sensing, petroleum leakage detection etc. In this paper we present our results on using this technique in petroleum leakage detection.
A PROBABILISTIC DERIVATION OF WASTE CONCENTRATION LIMITS FOR THE RADIOACTIVE WASTE MANAGEMENT SITES AT THE NEVADA TEST SITE

A probabilistic approach to performance assessment was used to derive waste concentration limits for the Area 5 and Area 3 Radioactive Waste Management Sites at the Nevada Test Site (NTS). Probabilistic techniques employed in the performance assessments include probabilistic treatment of parameter uncertainty, the occurrence of inadvertent human intrusion scenarios, and the longevity of institutional controls. Sitespecific and probabilistic treatment of the intruder at NTS is appropriate given the location of the low-level waste disposal facilities in a remote desert environment. The probability of intrusion and the length of the institutional control period was estimated from the elicitation of a panel of subject matter experts (SMEs). The SMEs concluded that the probability of future inadvertent human intrusion and human settlement would be very low in the remote arid valleys of the NTS. Moreover, the SMEs believed that institutional controls were likely to be effective beyond 100 years at the NTS. The NTS SMEs estimated the probabilities of inadvertent human intrusion for a 10,000year compliance period and a 0.8-hectare disposal site footprint. Application of elicitation-derived intruder probabilities to the disposal facilities was a three-step process: 1) adjust probabilities to a 1,000-year performance assessment compliance period based on new regulatory guidance; 2) adjust probabilities to the actual footprint of the waste cell; and 3) adjust for an elicitation-derived institutional control period of 250 years. The probability-weighted dose, or expected dose to an intruder for a disposal cell at the NTS, was determined by multiplying the dose by the probability of a well-drilling intruder scenario. When the intruder performance objectives were found to be limiting, waste concentration limits were derived for select radionuclides using the probability-weighted intruder dose. The paper explores the benefits of the NTS probabilistic approach on waste concentration limits: • accounting for site-specific conditions at the waste disposal facility allows full credit to be taken for the advantages offered by a remote, arid site
A micromachined 4-port optical switch with no propagation length difference for add drop modules

We demonstrate a micromachined 4-port optical switch with 4 moving micromirrors. It features no propagation length difference and requires no collimators or planar lightwave circuits for low insertion loss. The optical performances were evaluated using 8 optical fibers (4 input-output pairs) of thermally expanded core (TEC) fibers.
Assessing Cloud Transient Impacts of Solar and Battery Energy Systems on Grid Inertial Responses

Abstract To assess the dynamic impact of intermittency of rapidly increasing solar photovoltaic generation on the grid, this article presents the modeling and integration of the components that need to be considered, including the solar photovoltaic plant, battery energy storage system, grid-tied interface, and associated control systems. The complexity and accuracy of these models are suitable for evaluating the transient impact on bulk power systems. Of particular interest is the grid inertial response in such situations as different penetration levels of solar generation and fast cloud transient induced solar generation decrease coupled with outages that recurrently occur in the grid, e.g., a generator trip. The impact of such events on the grid frequency responses is investigated using a simplified simulation approach to account for the locational or spatial irradiance variation patterns and cloud movements. Responsive battery energy storage systems are recognized as an effective means to improve the inertial response.
Design of Feedback Controller for Boost Converter Using Optimization Technique

In this paper a new method of controller design for boost type dc-dc converter is proposed. A feedback controller for DC-DC boost converter is designed to obtain constant output voltage of 24v.The optimal values of feedback controller is obtained using Genetic Algorithm (GA). Design equations are derived and it is modeled in MATLAB. Extensive simulation is carried out with linear controller parameters and the results are presented. To compare the output of the GA based design and BFOA, the controller parameters are also determined using conventional method (Z-N). Simulation results are validated through hardware results.
Determination of Thermal Barrier Coatings Average Surface Temperature After Engine Operation for Lifetime Validation

Assessment of ex-service parts is important for power generation industry. It gives the opportunity to correlate part conditions to specific operating conditions like fuel used, local atmospheric conditions, operating regime, and temperature load. For assessment of thermal barrier coatings, one of the most valuable information is the local thermal condition. A method has been developed in Alstom, allowing determination of a thermal barrier coating average surface temperature after engine operation. It is based on the analysis of the phase composition of the thermal barrier coating by the acquisition of an X-Ray diffraction spectrum of the coating surface, and its analysis using Rietveld refinement. The method has been validated by comparing its outcome to thermal models and base metal temperature mapping data. It is used for assessment of combustor and turbine coatings with various purposes: determination of remnant coating life, building of lifing models, or determination of the coating degradation mechanisms under some specific operating conditions. Examples will be presented showing applications of this method.