Miracle-dz/UniFAR-FTUs huggingface dataset:
Application of Particle Swarm Optimization Technique for the Design of Maximum Power Point Tracking

The generation of electricity from solar energy has gained worldwide acceptance and serves as a critical objective for the future due to its abundance and eco-friendly nature. However, the output power extracted from solar PV module varies based on the variation in environmental conditions such as irradiance, temperature, shadow etc. Therefore, Maximum Power Point Tracking (MPPT) algorithms are implemented for the proper utilization of the available photovoltaic energy. This paper proposes an algorithm using Particle Swarm Optimization technique which involves a simple and effective method to calculate the required duty cycle. The key feature of this method is its ability to track the maximum power accurately with almost zero steady state oscillations which in turn improves the performance of the tracking system. The effectiveness of this algorithm has been evaluated under uniform change in environmental conditions in MATLAB/SIMULINK. Moreover, superiority of the proposed method is verified by comparing its results with the conventional algorithms such as Hill Climbing and Incremental Conductance in terms of tracking speed and steady state oscillations.
A Coupled Finite Element Model of Thermo-Elastic-Plastic Large Deformation for Orthogonal Cutting

In this paper, a coupled model of the thermo-elastic-plastic material under large deformation for orthogonal cutting is constructed. A chip separation criterion based on the critical value of the strain energy density is introduced into the analytical model. A scheme of twin node processing and a concept of loading/unloading are also presented for chip formation. The flow stress is taken as a function of strain, strain rate and temperature in order to reflect realistic behavior in metal cutting. The cutting tool is incrementally advanced forward from an incipient stage of tool-workpiece engagement to a steady state of chip formation. The finite difference method is adopted to determine the temperature distribution within the chip and tool, and a finite element method, which is based on the thermo-elastic-plastic large deformation model, is used to simulate the entire metal cutting process. Finally, the chip geometry, residual stresses in the machined surface, temperature distributions within the chip and tool, and tool forces are obtained by simulation. The calculated cutting forces agree quite well with the experimental results. It has also been verified that the chip separation criterion value based on the strain energy density is a material constant and is independent of uncut chip thickness.
The Top Loading Antenna with Fractal Photonic Crystal Used in TD-LTE System

The performance of antenna has the conclusive influence to the performance of mobile communication terminal; one excellent-performance antenna can improve the communication quality of communication device greatly. With the developing of broadband wireless communication technology, the fourth generation mobile communication technology has advanced day after day, and will turn into practical soon. This article aim at the demand of the fourth generation mobile communication technologys standard of TD-LTE, combined with the fractal technology, photonic crystal texture and top loading technique, designing a fractal photonic crystal top loading antenna which can work in 2.6GHz frequency band, and make simulate analysis to the performance of antenna and make the sample of antenna to test. The result from simulation and test shows this antenna has a low return loss and the work bandwidth is big, which is suitable for the fourth generation mobile communications TD-LTE system.
Characterization of Substrate Materials for System-in-a-Package Applications

System-in-a-Package (SiP) aims to integrate the entire system functions within a system-level package containing multiple ICs and other components interconnected in a high-density substrate. A structure based on the SiP concept is proposed in this paper. Based onthis SiP structure, four substrate candidates, namely FR4, liquid crystal polymer (LCP),teﬂon (PTFE) and low temperature co-ﬁred ceramic (LTCC) were compared by assessingand measuring their mechanical reliability, electrical performance and environmentalinﬂuence. First, to evaluate long-term reliability, the 3D ﬁnite element method (FEM) wasused to calculate the stress distribution and warpage of the whole package. Both three-point bending and cooling in the manufacturing process were taken into consideration.The LCP has a coefﬁcient of thermal expansion (CTE) close to that of the silicon chip,and a Young’s module close to that of FR4, which gave the best reliability in both bendingand cooling situations. Next, the dielectric constants and the loss tangent for the foursubstrates were evaluated in the electrical performance investigation. The LCP has a lowrelative dielectric constant and a low dissipation factor for the frequency range 1 GHz to35 GHz, making it a good substrate for high frequency applications. An environmentalassessment included several environmental impact categories; this assessment indicatedthat LCP is the most environmentally acceptable substrate. @DOI: 10.1115/1.1648057#
Control of a Space Rigidizable Inflatable Boom Using Macro-fiber Composite Actuators

An experimental investigation of vibration testing and active control of a space rigidizable inflatable composite boom containing embedded piezoelectric composite actuators was conducted. Inflatable deployable space structures offer reduced mass, higher packaging efficiency, lower life cycle cost, simpler design with fewer parts, and higher deployment reliability for many large deployable spacecraft structures applications. Enhancing deployed precision and repeatability for these structures is an ongoing research area, in particular for rigidizable inflatable material systems. In this study, in situ vibration testing and active damping using piezoelectric macro-fiber composite actuators embedded within a typical space-rigidizable deployable composite boom are investigated The embedded macro-fiber composites are shown to be capable of surviving integration, packaging, deployment and thermal rigidization in vacuum, and subsequently operating at their full actuation capability. Positive position feedback controllers using accelerometer, laser vibrometer, and strain gage feedback signals are designed and experimentally evaluated. Velocity-proportional and acceleration-proportional controllers are shown to be capable of attenuating fundamental bending response significantly using only modest control authority (—23dB with 10% of available voltage).
Analytical method for determining equivalent circuit parameters of GaAs FETs

An analytical method has been developed that gives a simple and practical means of extracting small-signal equivalent circuit parameters (ECPs) of GaAs FETs with negligibly small bond-pad capacitances. Only the S-parameter measurement of the pinched-off cold field-effect transistor (FET) is enough to determine the extrinsic FET ECPs. The intrinsic FET ECPs of a medium-power Ku-band GaAs FET chip with a total gate width of 800 /spl mu/m have been analytically extracted for two types of eight-element intrinsic FET models; Model 1 (Curtice model) and Model 2 that differ in the control voltage (V/sub G/) definition. Model 2 with V/sub G/ defined across the gate-source capacitance is found more appropriate judging from the smaller frequency dependence of the ECPs and a better agreement between the calculated and measured S-parameters over 2-20 GHz.
Simulation and performance evaluation of partially and fully integrated sales and operations planning

This article presents rolling horizon simulation models and performance analysis of partially and fully integrated sales and operations planning (S&OP) against traditional decoupled planning in a multi-site make-to-order (MTO) based manufacturing supply chain. Three simulation models are developed illustrating, respectively, the fully integrated S&OP model, which integrates cross-functional planning of sales, production, distribution, and procurement centrally; the partially integrated S&OP model, in which the joint sales and production planning is performed centrally while distribution and procurement are planned separately at each site; and the decoupled planning model, in which sales planning is carried out centrally while production, distribution, and procurement are planned separately and locally. A solution procedure is provided for each model so that a more realistic planning process can be simulated. Performances of rolling horizon simulation models are evaluated against those of the fixed horizon deterministic models. The results demonstrate that while deterministic models are important for theoretical studies, they are insufficient for decision support and performance evaluations in a real business environment. A rolling horizon simulation model is required to provide more realistic solutions. The effects of demand uncertainties and forecast inaccuracies are incorporated in the evaluation. The study is carried out based on a real industrial case of a Canadian-based oriented strand board (OSB) manufacturing company.
New Environmentally Safe High-Temperature Water-Based Drilling-Fluid System

A new, environmentally safe water-based polymer system has been developed for drilling applications with temperatures up to 232 C (450 F) and high pressures. The system components are newly developed synthetic polymers that do not contain chromium or other environmentally harmful materials. These new synthetic polymers are designed to perform specific functions at high temperatures and the innovative designs of these thermally stable polymers allow for the use of a minimum number of products in the formulation of high-temperature fluids. The new system consists of two basic polymeric components for rheology and filtration control at high temperatures. High-temperature fluid formulations are greatly simplified utilizing this new system, with only the two polymeric components being required, along with a pH control additive, weight material,l and small amounts of clay for filter cake quality. This simplicity is a significant advantage over traditional high-temperature systems, which normally require the use of a large number of additives to control or limit the effects of thermal degradation. The new system may be formulated with fresh water or sea water, providing flexibility for a variety of drilling environments. Excellent resistance to common contaminants, such as calcium and magnesium hardness and solids accumulation, is another important characteristicmore » of this new system. This paper will review the previous state of the art with respect to high-temperature, water-based muds and will generically discuss the unique chemistry of the newly developed polymer system components. System formulation and application will be discussed. « less
Singularity-Free Joint Actuation in Omnidirectional Mobile Platforms With Powered Offset Caster Wheels

This paper presents the analysis of singularity and motion capability of a mobile platform articulated by offset powered caster wheels. Specifically, it presents the analysis of the equations of motion resulting in the sufficient and necessary actuation condition to yield a workspace that is entirely free of singular configurations. This paper shows that powering both the steer and drive joints on two sets of offset caster wheels in a mobile platform guarantees a singularity-free condition throughout the entire workspace. Analysis and discussion on equations of motions that lead to this result are presented.
The application of TQM: organic or mechanistic?

Purpose – This paper aims to examine the application of Total Quality Management (TQM) in five organizations in light of the assumption that its implementation is an ongoing negotiated order rather than an objective reality as often accepted by the literature. Guided by a theoretical framework identified by Spencer (1994), the perceptions of a cross‐section of managers and employees in these organizations are used to establish the nature of applied TQM in terms of mechanistic and organic “mental models” of organization.Design/methodology/approach – The paper shows that research methodology is qualitative, and evidence was collected primarily through semi‐structured in‐depth interviews. A non‐quantifying general analytic methodology was used to analyse the evidence collected via convenience sampling.Findings – The findings in this paper indicate that, in three of the organizations, TQM is being applied in generally organic ways. In the other two organizations, strong influences of the mechanistic model wer.
Analyzing longitudinal‐mode of single‐frequency ring fiber laser

To realize single‐frequency of the fiber laser, a ring configuration is devised. The single‐frequency operation is realized at 1549.63 nm by using a fiber Bragg grating (FBG) as wavelength‐selective element and a unpumped 1.5 m‐long erbium‐doped fiber, which can produce standing‐wave saturation effects in the cavity. A measurement method based on fiber‐coupling scanning Fabry–Perot (F‐P) interferometer at 1.55 μm is designed. The laser longitudinal‐mode spacing is 11.1 MHz. The single‐frequency is observed by the interferometer with free spectrum range (FSR) of 7.5 GHz. The longitudinal‐mode fabric is analyzed by the interferometer with FSR of 1.5 GHz. As the cavity length increases, the longitudinal‐mode spacing changes to 3.7 MHz. The structures of longitudinal‐modes under different cavity lengths are compared. The longitudinal‐mode linewidth of 20 MHz is measured. Experimental results show that single‐frequency of the fiber laser can be approved accurately, and the effectiveness of the method, which can analyze longitudinal‐mode of the fiber laser with scanning Fabry–Perot (F‐P) interferometer, is improved. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1494–1497, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI.10. 1002/mop.22467
Evaluation of the quality of clinical laboratory services in the University Hospital of Kinshasa, Democratic Republic of the Congo

The evaluation of the quality of a service is the critical assessment of the degree to which the service, or its component, provides customers’ satisfaction. Monitoring customer satisfaction is an important and useful quality improvement tool for clinical laboratories and health care organizations. The purpose of this research is to evaluate the satisfaction level with laboratory services among attending physicians and to identify factors associated with satisfaction and priorities for quality improvement. A cross-sectional study was conducted at the University Hospital of Kinshasa. Data were collected through a reliable and valid interviewer-administered questionnaire and analyzed by using SPSS version 21. The correlation between associated factors and customer satisfaction was analyzed using the chi-square test and multivariate regression analysis. The Importance-Performance Analysis was the determinant of improvement priority. The overall level of customers’ satisfaction toward clinical laboratory services in this study was 45.2% with a response rate of 330 (100%). Gender (ORadj = 1.75, 95% CI 1.06, 2.91), Department (ORadj = 3.09, 95% CI 1.50, 6.37) and academic title (ORadj = 6.85, 95% CI 3.51, 8.81) were found to have a statistically significant association with the overall satisfaction. Results accuracy (I = 0.944, P = 4.7), laboratory turnaround time (I = 0.932, P = 4.8), and availability of all the tests requested by physicians (I = 0.917, P = 4.9) were the most important opportunities for quality improvement. The overall level of customers’ satisfaction with laboratory services was low. Thus, the laboratory management must establish preventive and corrective measures to improve the results’ accuracy, reduce the laboratory turnaround time, and ensure the availability of all the tests requested by physicians. Keywords: Customers satisfaction, clinical laboratory, services’ quality, continuous improvement, Democratic Republic of the Congo.
Multi-phase, 2-kilowatt, high-voltage, regulated power supply

Development of a flight configured experimental power supply delivering 2 kw of conditioned power represents a concentrated effort at advancing the state-of-the-art in high voltage power supplies for space application. The power supply described herein was designed for use with the Jet Propulsion Laboratory (JPL) 20 cm Mercury Ion Thruster. However, its modularized design philosophy allows adaptation to various high voltage, high power requirements. Areas of principal concern are design of power and control circuits, performance parameters, packaging, efficiency, and weight.
Development of a flexible three-axis tactile sensor based on screen-printed carbon nanotube-polymer composite

A flexible, three-axis carbon nanotube (CNT)–polymer composite-based tactile sensor is presented. The proposed sensor consists of a flexible substrate, four sensing cells, and a bump structure. A CNT–polydimethylsiloxane (PDMS) composite is produced by a solvent evaporation method, and thus, the CNTs are well-dispersed within the PDMS matrix. The composite is directly patterned onto a flexible substrate using a screen printing technique to fabricate a sensor with four sensing cells. When a force is applied on the bump, the magnitude and direction of force could be detected by comparing the changes in electrical resistance of each sensing cell caused by the piezoresistive effect of the composite. The experimentally verified sensing characteristics of the fabricated sensor exhibit a linear relationship between the resistance change and the applied force, and the measured sensitivities of the sensor for the normal and shear forces are 6.67 and 86.7%/N for forces up to 2.0 and 0.5 N, respectively. Experiments to verify the load-sensing repeatability show a maximum 2.00% deviation of the resistance change within the tested force range.
Nurses’ Perceptions and Experiences of Rotating-Shift Work in Acute Hospitals: A Qualitative Study

Background: An 8-hour shift system with faster rotation (e.g., shift changes every 2 to 5 days) is common for nurses at acute hospitals in Korea. However, there is a lack of information regarding nurses’ perceptions and experiences of rotating shift schedules, as well as the ways in which rotating-shift work affects patient outcomes. This study aimed to identify and describe emergent themes and offer new insights into nurses’ perceptions and experiences of rotating-shift work in Korea. Moreover, it explored the relationship between rotating-shift work and nurse and patient outcomes.Methods: A qualitative descriptive design was employed. Focus group interviews were conducted with 24 rotating-shift nurses at Korean acute care hospitals. Qualitative data were collected between January and February 2019, and conventional content analysis was employed. Results: Three themes and eight subthemes emerged. Major themes were unsatisfactory work schedules, the impact of shift work on nurses' lives, and the impact of schedule-related fatigue on overall work performance.Conclusion: Study findings highlight the importance of optimal scheduling, to reduce fatigue among rotating-shift nurses. Managers and administrators may improve nurse performance and patient safety by reviewing scheduling practices, considering the potential impact of shift schedules on nurse and patient outcomes, and addressing nurse’s scheduling issues. Furthermore, hospital authorities should consider revising schedules to include sufficient breaks between shifts. This study addressed issues that stem from rotating shift work, affecting both nurses and patients. Nurse interviews clarified these issues, which were classified according to theme. This study aimed to find practical solutions for shift planning problems, particularly in Korea, and to inform the development of scheduling guidelines for rotating-shift work in the future.
Low Profile ZnO Growth on Si Wafer Using Hydrothermal Method for Sensor Applications

ZnO was grown on a silicon wafer (1 cm x 1 cm) via hydrothermal method in this study. Initially, the zinc oxide colloid solution was spin-coated on the Si wafer at 400 rpm for 30 s for the seeding process prior to the ZnO growth. The presence of ZnO from the growing process was confirmed with the X-ray diffraction (XRD). The crystallite size was calculated to be 6.34 nm using Scherer equation. In addition, an energy dispersive X-ray (EDX) characterization was carried out to further verify the presence of the ZnO. Meanwhile, the scanning electron microscopy (SEM) characterization was done to observe the surface morphology of the sample. It is found that the ZnO structure has a coral-like shape, which is full of asperities and sharp edges. The sample was able to generate a voltage in the range of 180 mV to 240 mV peak to peak under random pressure.
Vibration Control System Using Electromagnetic Forces

This paper presents the concept of a new vibration control system in which motions of an Al-Fe alloy thin beam/plate with magnetized segments can be suppressed or activated through electromagnetic forces induced by an applied electric current. Analytical evaluation of the induced electromagnetic forces acting both on the electric current applied and on the magnetized segments are derived from an electromagnetic consideration. To examine the feasibility of the proposed vibration control system, we have formulated a simple regulator problem in which the disturbed motion of the thin alloy beam caused by an impulsive force is suppressed.
Position sensorless control for interior permanent magnet synchronous motor using adaptive flux observer with inductance identification

A position sensorless control of interior permanent magnet synchronous motors (IPMSMs) is proposed using the adaptive full-order observer with inductance identification. First, mathematical models are discussed for robustness improvement to inductance variation and inductance identification in IPMSMs, the models show that a high-frequency signal needs to be injected to identify the inductance. Next, novel adaptive schemes for inductance identification are proposed here. Finally, identification experiments under IPMSM position sensorless control are carried out with the proposed methods, in which the feasibility and effectiveness of the methods are shown in terms of inductance identification performance and the convergence of position estimation error.
Quasi-optical 225GHz polarization converter

Recently, system designers have looked toward the higher frequency, shorter wavelength (to THz), consequently the device requires smaller and more precision. And this paper describes a polarization converter works in the radar system set-up at 225 GHz. Its working principle is similar to the optical diffraction. After simulations, the model size is confirmed and the data show a good result. And this component have an advantage is easy to machining. It also can be used in other frequency band through adjusting its size.
33.2: High‐Efficiency Integrated Charge Pump Circuits for Poly‐Si TFT‐LCDs

A novel charge pump circuit composed of poly‐Si TFTs has been designed for LTPS TFT‐LCDs to generate high voltage level. The proposed configuration is based on connecting two identical but opposite‐phase switched‐capacitor type charge pumps in parallel, thus eliminating the need for extra voltage boost circuits. The simply clock scheme is very suitable for integrated poly‐Si AMLCDs. Excellent TFT performance also enables the external voltage to the charge pump circuit down to 3V below. The simulated power efficiency of the proposed charge pump circuit is beyond 70%.