Miracle-dz/UniFAR-FTUs huggingface dataset:
Steady‐state stability of shaft torsional oscillation in an ac‐dc interconnected system with self‐commutated converters

Recent progress in power electronics technology makes it possible to consider applying self-commutated converters using gate turn-off thyristors (GTOs) to HVDC transmission systems. Since the self-commutated converter can be operated stably without depending on ac-side voltage, the magnitude and the phase angle of the converter output voltage can be controlled independently. Therefore, this type of converter will improve voltage stability at its ac side. On the other hand, shaft torsional oscillation of a thermal power plant caused by the interaction between the shaft-generator system and the control system of the self-commutated converter is still an open problem. In this paper, a linearized model for eigenvalue analysis of a power system, including HVDC interconnection with self-commutated converters, is described to analyze the effect of the self-commutated converter on the shaft torsional oscillation of a thermal power plant. Then, numerical results from the eigenvalue analysis of the shaft torsional oscillation are presented. Results obtained by the frequency response method are also reported. The numerical results make it clear that parameter regions of DC-AVR and ACR control systems of self-commutated converters exist where the shaft torsional oscillation may be caused. © 1999 Scripta Technica, Electr Eng Jpn, 128(4): 25–37, 1999
Fuel axial relocation in ballooning fuel rods. [PWR; BWR]

Fuel movement, in the longitudinal direction in ballooning fuel rods, shifts the position of heat generation and may cause an increase in cladding temperature in the ballooning region. This paper summarizes the axial fuel relocation data obtained in fuel rod tests conducted in the United States and the Federal Republic of Germany, describes a model for calculating fuel axial relocation, and gives a quantitative analysis of the impact of fuel relocation on cladding temperature. The amount of fuel relocation in 18 ballooned fuel rods was determined from neutron radiographs, niobium gamma decay counts, and photomicrographs. The fuel rods had burnups in the range of 0 to 35,000 MWd/t and cladding hoop strains varying from 0 to 72%.
Behaviour of a unimorph circular piezoelectric actuator

This paper investigates the deflected behavior of unimorph circular piezoelectric diaphragm actuators under electrical loading. Among many other factors that affect the actuators’ performance, the effects of the boundary conditions, the thickness ratio of piezoelectric to substrate layers, and the radius of piezoelectric layer bonded to the metallic substrate on the resulting deflection of circular actuators are examined. Analytical models are presented with which to optimize the thickness ratio, and the radius ratio of piezoelectric to substrate for various boundary conditions. Experimental results for two circular actuators with different piezoelectric coverage are also demonstrated to validate the models. The measured deflections for the experimentally tested clamped diaphragms show close correlation with the analytical transverse deflections for elastically supported edge. The analytical solutions presented here can be used to optimize the transverse deflection of circular piezoelectric diaphragm actuators.
The analysis on nonlinear control of the aircraft arresting system

The aircraft arresting system is a complicated nonlinear system. This paper analyzes the mechanical-hydraulic structure of aircraft arresting system composed of electro hydraulic valve and establishes the dynamic equation of the aircraft arresting system. Based on the state-feedback linearization of nonlinear system, a PD-based controller is synthesized. Simulation studies indicate, while arresting the different type aircraft, the proposed controller has fast response, good tracking performance and strong robustness. By tuning the parameters of the PD controller, a satisfactory control performance can be guaranteed.
Effect of Active and Passive Fatigue on Performance Using a Driving Simulator

The present study investigated the effects of active fatigue (e.g., elevated distress) and passive fatigue (e.g., decreased task engagement) on driving performance. The study used similar manipulations developed by Saxby et al. (2007), which were shown to induce active and passive fatigue states. 168 undergraduates participated. There were 3 conditions (active, passive, control) and 2 durations (10, 30 minutes). The active condition used simulated wind gusts to increase the required number of steering and acceleration changes, while the passive condition was fully automated. In the control condition, drivers were in full control of steering and acceleration. Data confirmed that, over time, passive fatigue is expressed as decreasing task engagement. Furthermore, drivers in the passive condition had slower response times to an unexpected event and were more likely to crash than those in the active and control conditions. Theoretical and practical implications are discussed.
An Assessment of the Accuracy of Quantity Surveyors' Preliminary Cost Estimates in Nigeria

Accuracy of quantity surveyors’ preliminary cost estimates was evaluated through a questionnaire survey administered on quantity surveying firms in Nigeria. A total of 24 quantity surveying firms were surveyed and data on 40 completed and on-going projects collected to quantitatively measure the degree of accuracy of quantity surveyors’ preliminary cost estimates. The survey also evaluated preliminary cost estimating procedures employed generally. Within the limitation of the sample data analysed, it was concluded that quantity surveyors’ preliminary cost estimates in Nigeria were not significantly biased. However, the consistency of the estimates was found to be unsatisfactory and as such, an issue that needs to be addressed. Using analysis of variance (ANOVA), the paper also concluded that estimating accuracy improved with increasing contract size. However, for very large contracts, this was found to be contrary; the reasons adduced being time lag between preliminary cost estimate and invitation of tenders and political factors that are common with such projects.
Canadian Kiln Drying Survey: Benchmarks of Problems and Issues and a Comparison to Europe

Despite the importance of the wood products industry to Canada, scarce information currently exists regarding the general kiln drying situation across the country. A mail survey was conducted to benchmark the kiln drying problems and issues that the industry faces. Topics covered by the study included dried product quality problems, drying process and kiln control issues, and level of kiln drying related knowledge of different groups of stakeholders such as kiln operators, kiln equipment suppliers, distributors, sales personnel and customers. The research design allowed a comparison of these results with kiln drying problems and issues in major European lumber producing countries. Results indicated that drying process and kiln control issues were generally considered important to Canadian producers, with the most important ones being quality control during drying and airflow. Dried product quality issues were only of moderate concern, with the spread of final moisture content between boards and achieving target moisture content being considered the most pressing issues. Finally, various stakeholders appeared to be knowledgeable about kiln drying issues, with kiln operators having the highest level of knowledge. The comparison between the kiln drying situation in Canada and Europe revealed that drying process and kiln control issues were more important for Canadian companies than for the European counterparts. However, dried product quality issues were considered to be more serious in Europe. A possible explanation for these results is the structure of the Canadian wood products industry, which is more focused on primary wood products and volume maximization and less concerned about product quality. The generally superior wood supply in Canada could also account for fewer problems with drying defects.
Wavelength division multiplexing devices with high-wavelength shift tolerance and their applications in broadband network communication applications

Wavelength division multiplexers (WDMs) with high-wavelength-shift-tolerance (HWST) are proposed for both multi-mode and single-mode regimes, based on a 1:1 magnification transmission lens imaging system combined with a Littrow grating configuration. The HWST WDMs have a high wavelength-packing-ratio; up to 1:2. In this paper, their optical properties are discussed, and related technological problems are analyzed. In addition, design and experimental results, as well as current applications for both multi- and single-mode WDM devices are provided.
Frequency domain lifetime characterization

Time-based measurements are commonly used for lifetime characterization of semiconductors. We have developed the theory, verified by experiment, of frequency-based lifetime characterization as an alternative to time-based measurements for MOS devices biased in inversion. One consideration during lifetime/diffusion length measurements, is whether the near-surface space-charge region or the bulk or quasineutral region is characterized. To characterize the near-surface space-charge region of the device, one usually makes room temperature pulsed MOS capacitor or diode leakage current measurements. We show that room-temperature, frequency-domain capacitance, conductance, or resistance measurements characterize the quasineutral bulk, not the space charge region, in contrast to room-temperature pulsed MOS-C or diode leakage current measurements which characterize the space-charge region.
Water pump mechanical faults display at various frequency resolutions

When an electrical machine suffered a mechanical fault, it generally emits certain sounds. These sounds came from the vibration. Therefore, based on the vibration, it could be detected if there was a mechanical fault in an electrical machine. This paper discussed the graphical display of the vibration of electrical machines in the form of household water pumps which were in good condition, faulty bearing, faulty impeller, or faulty foot valve. Vibration could be displayed in the time domain, or in the frequency domain, by using the three axes, i.e. X, Y, and Z. In the frequency domain, the vibration could be displayed at various frequency resolutions. Based on the observations, the higher frequency resolution, the lower detail in the graphical display of frequency domain would be shown. Although there was lower detail in the graphical display of frequency domain, at frequency resolution of 11.7 Hz in the X axis, showed that it could be visually distinguished among water pumps which were in good condition, faulty bearing, faulty impeller, or faulty foot valve.
DOM CASMURRO

Uma noite destas, vindo da cidade para o Engenho Novo, encontrei num trem da Central um rapaz aqui do bairro, que eu conheço de vista e de chapéu. Cumprimentou-me, sentou-se ao pé de mim, falou da lua e dos ministros, e acabou recitando-me versos. A viagem era curta, e os versos pode ser que não fossem inteiramente maus. Sucedeu, porém, que, como eu estava cansado, fechei os olhos três ou quatro vezes; tanto bastou para que ele interrompesse a leitura e metesse os versos no bolso.
DEA-Analysis Of The Effectiveness Of The Country’s Information Security System

The consequences of the fourth industrial revolution caused an increase in the level of computerization and digitalization of society, which led to problems related to the protection of information of individual users, companies and the state as a whole. The aim of this paper is to analyze the effectiveness of the information security system of countries in terms of its ability to counter information threats. Two groups of input indicators were used for this purpose. The first group was formed by 12 indicators of the country’s world development, which were selected from the World Bank database and based on the results of correlation analysis. The second group includes 5 information technology indicators that characterize certain areas of information security: information technology development, digitalization of the country, countries’ commitment to cybersecurity, readiness to counter cyber threats and use the latest information and communication technologies. The country’s information security threat index is used as a starting point. Data from 159 countries of the world for 2018 were taken for the analysis, as for this number of countries and period there is a complete set of data on selected indicators. Country data were considered based on clusters, which allowed the use of 7 groups. The analysis was performed using the analytical tool Frontier Analyst. The study built CRR and BCC models, among which CRR was preferred, which allowed a more critical assessment of the potential of countries. The paper analyzes the structural effectiveness of socio-economic development indicators and information security indicators of countries, considering the current level of the information security threat index. As a result, the following were identified: an increase in government security spending for zero-cluster countries; the need to transform the information technology component for the countries of the first and second clusters; increasing personal protection, strengthening corruption control and legal regulation for third cluster countries; the need for economic growth and higher social standards for the fourth, fifth and sixth clusters. The obtained models allowed us to estimate the maximum level of growth of the information security threat index with the available resource potential of the country. As a result, it was found that the largest increase in the information security threat index is possible due to the existing potential of the countries of the zero and fifth clusters, which will increase the effectiveness of their response to information threats. Keywords: BBC-model, CCR-model, Data Envelopment Analysis, socio-economic development, information, threat, security.
Control of the vertical motion of a hydrofoil vessel

This paper presents the motion control of a fast ship equipped with fully submerged hydrofoils in following waves. The change of lift force produced by the orbital motion of fluid particles is included as a time-varying disturbance in the equation of coupled heave and pitch motions, and the corresponding state-space equation is derived. Three control algorithms, including proportional–integral–derivative (PID), linear quadratic regulator (LQR) and sliding mode controls are applied for regular and irregular wave conditions, and the subsequent motion responses are compared. Motion responses are also compared with existing experimental data to observe the effectiveness of each algorithm. In order to investigate the robustness of each control algorithm, systematic motion simulations are performed for various wavelengths and wave heights. PID control is easy to implement as is well known, however a poor performance is observed in irregular waves. LQR control predicts robust and stable motion and acceleration throughout all the simulations. Sliding mode control shows excellent performance particularly when the disturbance is known, despite its sensitivity to wave environments.
Effects of Internal Combustion Engine Vibrations on Vehicle Ride Comfort

25 www.wjrr. org  Abstract— The vibration sources of the internal combustion Engine (ICE) are widely known to affect not only the noise but also the vehicle ride comfort. In order to evaluate their effects on vehicle ride comfort, a full-vehicle dynamic model with 10 degree of freedoms combining from road surface roughness and ICE excitations is established. The vehicle ride comfort with ICE vibrations is compared to that without ICE vibration based on the values of the root mean square (r.m.s) acceleration responses of motion, pitch and roll angles of vehicle body according to the international standard ISO 2631-1 (1997). The results indicate that the ICE vibrations have a significant effect on vehicle ride comfort. The study results also provide a theoretical basis for designers and researchers in the field of dynamics and controlling of vehicle and ICE systems
Use of computers and applications by senior executives

Purpose: Analyze the relationship between the senior executive and ICT use. Design/methodology/approach: Empirical research through which we propose a framework to establish the main factors that might lead to an increase in ICT use by senior executives. Findings: The main contribution of the present study is the creation of the list of factors that affect the use of computers and applications by senior executives and a smaller group of categories. Research limitations/implications: A limitation of this research is that it should be confirmed by means of quantitative research that would allow us to test the validity of the proposed framework, and also to ascertain the relative importance of each factor. Practical implications: Thus reducing the number of factors and forming a smaller group of categories that can facilitate research. Originality/value: The list of factors that affect the use of computers and applications by senior executives and the smaller group of categories.
Transcriptome analysis identifies signaling pathways related to meat quality in broiler chickens – the ECM receptor interaction signaling pathway

Background Meat quality characteristics, including juiciness, flavor, and tenderness, can be mostly attributed to the total muscle fat content, intramuscular fat (IMF), and the composition of its fatty acids (FAs), which are regulated by the balance between lipid uptake, transport, synthesis, and subsequent metabolism, involving many genes and pathways. However, the detailed molecular mechanisms remain unclear. Results The present study reports the RNA-sequencing (RNA-seq) analysis of chest muscle and leg muscle tissue of the Zhuanghe dagu chicken (ZD chicken) and the Arbor Acres Broiler chicken (AA chicken). We identified certain differentially expressed genes that affect IMF deposition , such as EHHADH , TECRL , NDUFAB1 , PCCB , and HIBCH , which were upregulated in ZD chickens, and GCDH , TPI1 , ABHD13 , PSMC1 , MYST2 , and FBXO11 , which were upregulated in AA chickens. Pathway analysis using the Kyoto Encyclopedia of Genes and Genomes indicated that the extracellular matrix (ECM)–­receptor interaction pathway is co-enriched in both tissues, and forms a sub-pathway of other enriched pathways. Intriguingly, the ECM–receptor interaction pathway genes are regulated differently in different gene pools. Collagens, which are main ECM constituents, and laminin and integrinβ1 transmembrane receptors were significantly downregulated in both tissues of the AA chicken. Conclusions RNA-seq analysis of two tissues from two breeds of chicken hinted that interactions between transmembrane receptors and ECM components of fat cells affect breed-specific adipogenesis, which would affect quality and flavor of chicken meat. These findings will contribute to improving the quality attributes of chicken meat.
Enabling Capillary Self-Assembly for Microsystem Integration

Efficient and precise assembly of very-large quantities of sub-millimeter-sized devices onto pre-processed substrates is presently a key frontier for microelectronics, in its aspiration to large-scale mass production of devices with new functionalities and applications (e.g. thin dies embedded into flexible substrates, 3D microsystem integration). In this perspective, on the one hand established pickp assembly techniques may be unsuitable, due to a trade-off between throughput and placement accuracy and to difficulties in predictably handling very-small devices. On the other hand, self-assembly processes are massively parallel, may run unsupervised and allow contactless manipulation of objects. The convergence between robotic assembly and self-assembly, epitomized by capillarity-enhanced flip-chip assembly, can therefore enable an ideal technology meeting short-to-medium-term electronic packaging and assembly needs. The objective of this thesis is bridging the gap between academic proofs-of- concept of capillary self-assembly and its industrial application. Our work solves several issues relevant to capillary self-assembly of thin dies onto preprocessed substrates. Very-different phenomena and aspects of both scientific and technological interest coexist in such a broad context. They were tackled both experimentally and theoretically. After a critical review of the state-of-the-art in microsystem integration, a complete quasi-static study of lateral capillary meniscus forces is presented. Our experimental setup enables also a novel method to measure the contact angle of liquids. Recessed binding sites are introduced to obtain perfectly-conformal fluid dip-coating of patterned surfaces, which enables the effective and robust coding of geometrical information into binding sites to direct the assembly of parts. A general procedure to establish solder-mediated electro-mechanical interconnections between parts and substrate is validated. Smart surface chemistries are invoked to solve the issue of mutual adhesion between parts during the capillary self-assembly process. Two chemical kinetic-inspired analytic models of fluidic self-assembly are presented and criticized to introduce a novel agent-based model of the process. The latter approach allows realistic simulations by taking into account spatial factors and collision dynamics. Concluding speculations propose envisioned solutions to residual open issues and further perspectives for this field of rapidly-growing importance.
Combined PSK/ASK modulation format for the STARNET WDM local-area network

STARNET is a coherent optical wavelength division multiplexed (WDM) local area network. In STARNET, the use of low level amplitude modulation of phase modulated light has been proposed to implement a packet-switched ring network in addition to a high speed circuit- switched network. To verify the feasibility and characterize the effects of amplitude shift- keyed (ASK) modulation on a phase shift-keyed (PSK) receiver, we have measured the sensitivity of a 1.244 Gb/s PSK synchronous heterodyne receiver in the presence of 125 Mb/s ASK modulation. The experiments show that the unmodified (i.e., designed for no ASK modulation) PSK receiver successfully operates with a bit error ratio less than 10-9 and maintains phase-lock in the presence of ASK modulation for ASK modulation indexes less than 0.5.
Low stress dicing assisted by pulsed laser for multilayer MEMS

We have developed a novel debris-free in-air laser dicing technology, which is expected to give less failure of MEMS devices and hence improves yields. Our technology combines two processes: a dicing guide fabrication and a wafer separation process. The first process is internal transformation using a nanosecond Nd:YVO4 laser with high repetition rate and/or a pulsed fiber laser with 200ns pulsewidth. The laser pulses are focused inside the MEMS wafer without surface ablation. In order to make cross-sectional internal transformation, the laser beam is scanned several times with defocusing. The laser scanning speed per each scanning is 100-700 mm/sec depending on the layer material, the machining time is much faster than the conventional blade dicing. The second process is non-contact separation by thermally-induced crack propagation using a CO2 laser or mechanical separation by bending stress. In the each separation process, the internal transformation fabricated in the first process worked well as the guide of separation, and the processed wafer was diced with low stress. This dicing technology was applied for 4-inch MEMS wafers, e.g. pressure sensors, etc., and the sensor chips were separated without mechanical damages.