Miracle-dz/UniFAR-FTUs huggingface dataset:
Culture of Using Mobile Cranes for Building Construction

While tower cranes traditionally are identified with high-rise, congested urban building construction, and mobile cranes primarily are associated with heavy civil and infrastructure construction, there exists a vast population of building projects where both are feasible. The question, then, is: why are different crane types used under similar project conditions in different geographic areas (e.g., tower cranes in Europe, mobile cranes in the United States)? This paper examines the culture of using mobile cranes for building construction, as observed in the southwestern United States. Project-specific and environmental characteristics are identified, classified, and described, while comparatively relating to tower crane practice. The role of non–project-specific factors (such as planning culture, operating style, employment patterns, and market organization) is emphasized in shaping the mobile crane culture. A rather homogeneous population of projects with distinct features, such as short construction dur.
A 2-D analytic model for the threshold-voltage of fully depleted short gate-length Si-SOI MESFETs

A two-zone Green's function solution method is proposed to analytically model the potential distribution in the silicon film of fully depleted SOI MESFETs, in which the exact solution of 2-D Poisson's equation is obtained by using the appropriate boundary conditions. From the derived analytic 2-D potential distribution, the bottom potential in the active silicon film is used to analyze the drain-induced barrier lowering effect and the threshold voltage is defined in terms of minimum channel potential barrier. The results of the developed analytic threshold-voltage model are compared with those of 2-D numerical simulation, and good agreements are obtained for the gate length down to 0.1 /spl mu/m with wide ranges of structure parameters and bias conditions.
Aircraft Turbine Engine Control Research at NASA Glenn Research Center

This paper provides an overview of the aircraft turbine engine control research at NASA Glenn Research Center (GRC). A brief introduction to the engine control problem is first provided with a description of the state-of-the-art control law structure. A historical aspect of engine control development since the 1940s is then provided with a special emphasis on the contributions of GRC. With the increased emphasis on aircraft safety, enhanced performance, and affordability, as well as the need to reduce the environmental impact of aircraft, there are many new challenges being faced by the designers of aircraft propulsion systems. The Controls and Dynamics Branch (CDB) at the GRC is leading and participating in various projects to develop advanced propulsion controls and diagnostics technologies that will help meet the challenging goals of NASA Aeronautics Research Mission programs. The rest of the paper provides an overview of the various CDB technology development activities in aircraft engine control and diagnostics, both current and some accomplished in the recent past. The motivation for each of the research efforts, the research approach, technical challenges, and the key progress to date are summarized.
Performance characteristics of a 5 kW laboratory hall thruster

Abstract : The University of Michigan and United States Air Force Research Laboratory have jointly developed a 5 kW class Hall effect thruster. This thruster was developed to investigate, with a variety of diagnostics, a thruster similar to that specified by IHPRPT goals. The configuration of this thruster is adjustable so that diagnostic access to the interior of the thruster can be provided as necessary, and to allow for the exploration of various thruster geometries. At nominal conditions, the thruster was designed to operate at 5 kW with a predicted specific impulse of 2200 s. The actual operating parameters at 5 kW were 2326 s specific impulse, with 246 mN of thrust at an efficiency of 57%. These conditions are comparable to those of thrusters under commercial development, making the information learned from the study of this thruster applicable to the understanding of its commercial counterparts.
THE DEVELOPMENT OF AUTOMATED PATTERN RECOGNITION AND STATISTICAL FEATURE ISOLATION TECHNIQUES FOR THE DIAGNOSIS OF RECIPROCATING MACHINERY FAULTS USING ACOUSTIC EMISSION

Abstract This work presents techniques which can be used for the diagnosis of faults in reciprocating machines. The techniques are generic in nature but the applications considered here concentrate on the interrogation of acoustic emission (AE) signals acquired from three types of reciprocating machine under normal running and with various fault conditions. Analysis of the signals in the time domain enables identification of machine timing, which can then be used to isolate automatically those parts of the signal associated with specific mechanical events. Various statistical feature isolation and pattern recognition techniques are then used on a selected time window of the signal to identify machine fault conditions. The applications considered demonstrate the generic nature of this approach, which could be applied to the monitoring of many types of machines and faults using a variety of sensor data. The ultimate aim of the work, of which this paper is a part, is to provide a means of on-line automatic monitoring of reciprocating machines using AE without recourse to any additional sensors.
Effect of Short-term Flooding and Drainage on Soil Oxygenation

Three aeration indicators, namely oxygen (O2) concentration, redox potential (Eh), and oxygen diffusion rate (ODR), were measured to determine the aeration status of soil under short-term flooding and unflooded conditions. Relationships between these indicators were developed and results of some measurements made over short time intervals during flooding and drainage of soil are presented.
Understanding Gas-Well Load-Up Behavior

This paper describes the hydraulics of wellbore load-up for gas wells. A theoretical model of transient load-up hydraulics is presented and compared with field test data. Application of this technology allows predictive techniques to be used in analyzing gas-well load-up. It also establishes an understanding of load-up behavior, which is valuable in analyses of production problems and evaluations of production alternatives for low-pressure gas wells.
Fundamental Periods of Vibration of Braced Steel Frames for Seismic Design

An analytical study is performed to propose a simple expression for the fundamental period of vibration of concentrically braced steel frames. This work was carried out in the context of the development of the 2005 National Building Code of Canada (NBCC) and is mainly applicable to structures located in moderate and low seismic regions. Available field and test measurements of building periods are compared to analytical predictions. An empirical period formula is developed based on a survey of analytically computed building periods published in the literature. The influence of the 2005 NBCC design provisions on braced steel-frame periods is examined through a closed-form period solution and an extensive parametric study. Building periods are found to vary significantly with seismic hazard levels and soil conditions. An expression is tentatively proposed that provides reasonable lower-bound period estimates for most situations in Canada.
'Out of my kitchen!' Architecture, gender and domestic efficiency

The link between the kitchen and the image of a professional housewife was established in the first half of the twentieth century when industrial efficiency pervaded every aspect of society, including the privacy of the home. However, the initial application of efficiency principles in the home had been realised at an earlier stage by the introduction of more efficient means of communication between 'upstairs' and 'downstairs' in nineteenth-century upper-class households. The subsequent shortage of servants propelled all kinds of initiatives, not only collective district kitchens and apartment hotels, but also efficient kitchen designs fit for lonesome heroines, being middle-class housewives. The efficiency of step-saving kitchen designs, however, was thwarted by the position of the kitchen in the back of the house and the omission of a separate supplier's entrance. The absence of a separate supplier's entrance to the kitchen in combination with a provisioning system of daily door-to-door delivery forced housewives to run up and down the hallway to answer the door for suppliers and bill-collectors. In a period roughly between the late 1960s and the early 1980s the traditional floorplans of middle-class houses were restructured, inspired by the then-modern ideal of open plan living. The creation of spacious living freed women from their isolated position in the kitchen. Not only the outlook of kitchen cabinets was adjusted to the homey style of the living, but also kitchen duties were adjusted and integrated into a shared homelife on the ground floor. In this family theatre actors competed for visibility and applause.
Quality function development: a new paradigm for involving customers in product development process

The success of new products is determined particularly by the extent to which the producer succeeds in developing products that meet consumer demands. This implies that product development has to be fast in order to incorporate the latest trends in the product. Over the last few years an impressive body of research has accumulated on the topic of product development and the purpose of this article is to synthesise and to assess our understanding of involving users in the development process. In this paper, an attempt is made not only to analyse existing models of product development but also introduces an integrated concept and methodology to address these issues. The paper is composed of product development background, related literature review and list of steps for model development. The concepts presented in this paper are not yet widely practiced. Nevertheless, this work integrates several theories and practices into a useful framework.
Current transients in the small salient-pole alternator during sudden short-circuit and synchronisation events

Small salient-pole machines, in the range 30 kVA to 2 MVA, are often used in distributed generators, which in turn are likely to form the major constituent of power generation in power system islanding schemes or microgrids. In addition to power system faults, such as short-circuits, islanding contains an inherent risk of out-of-synchronism re-closure onto the main power system. To understand more fully the effect of these phenomena on a small salient-pole alternator, the armature and field currents from tests conducted on a 31.5 kVA machine are analysed. This study demonstrates that by resolving the voltage difference between the machine terminals and bus into direct and quadrature axis components, interesting properties of the transient currents are revealed. The presence of saliency and short time-constants cause intriguing differences between machine events such as out-of-phase synchronisations and sudden three-phase short-circuits.
Optimal supply chain configurations in semiconductor manufacturing

As a semiconductor supply chain becomes widespread and the competition pressure is very fierce, the detrimental effects of increasing varieties and variations are magnified in the supply chain. But many important issues, such as different service priorities, adaptability, controllability and scalability of performance metrics, have not been addressed in the literature. Conventional modelling techniques of supply chain operations are no longer effective for supply chain configuration. Therefore, a proposed empirical model was first built to catch up the relationship between supply-chain configuration and metrics under the influence of the variability sources. Next, an optimal supply chain configuration model is formulated as a polynomial goal programming model to accommodate different goal objectives. Finally, an efficient solution methodology is further developed to find out the optimal supply chain configuration. Our results show that our proposed approach can easily be adapted to the practices in semiconductor supply chain, and the solution methodology developed in this paper is truly promising.
Prolonged haemodialysis increases the risk of the impairment of global longitudinal strain in patient after kidney transplantation and a preserved ejection fraction of left ventricle

Background. Patients with chronic kidney disease, including these after kidney transplantation (KTx), have higher cardiovascular mortality. Global longitudinal strain (GLS) detects subtle changes in the left ventricle (LV) and is more sensitive predictor of cardiovascular mortality than the LV ejection fraction (LVEF). The aim of this study was to assess the prevalence of impaired GLS among kidney transplant recipients with preserved LVEF. We also aimed to identify possible clinical factors responsible for GLS impairment. Methods. A total of 79 patients following KTx with preserved LVEF and no history of cardiac disease were evaluated. We assessed echocardiogram parameters with the calculation of GLS, laboratory parameters, presence of diabetes, hypertension, duration of haemodialysis (HD) and time after KTx. An impaired GLS value was set on ≥-18%. The multivariate stepwise logistic regression analysis were used to identify the factors related to impaired GLS. Results. Among 79 (42 females, mean age 60.3) kidney transplant recipients with preserved LVEF, 39% had impaired GLS. ROC analysis revealed that the cut-off point for the prediction GLS ≥-18 % by HD duration is more than 28 months (AUC 0.67 (95%CI 0.545-0.79; P=0.007). In multivariate stepwise logistic regression analysis for variables related to impaired GLS duration of HD more than 28month is associated with GLS ≥-18( OR 4.06; 95CI (1.45-11.34) P=0.008). Conclusions. In our study group, a total of 39% of KTx patients with preserved LVEF had impaired GLS. The risk factor of GLS impairment was a prolonged duration of HD (>28months) prior to the transplantation procedure.
Exploring the Relationship between Industrial Economic Growth and Environmental Pollution - An Empirical Analysis Based on Cointegration and Granger Causality Test

This paper aims at investigating the cointegration relationship between industrial economic growth and environmental pollutions from the timing dimension by using three types of environmental pollution indicators of industrial emissions and going further to test whether this relationship is bidirectional Granger causality. Firstly, the cointegration analysis’ result shows that the relationship between industrial economic growth and environmental quality may not meet the hypothesis of EKC curve. In the timing period analyzed, the relationship is linear and positive. Hence, promoting the relationship to be negative when only relying on self-regulation of the market will probably not be achieved. Secondly, based on cointegration test, this paper goes further to conduct Granger causality test of cointegration relationship. The result shows industrial economic growth causes pollution emission but it is not true vice versa. The reasons possibly include that that the technological progress in recent years may not embody on the reduction of pollution emission intensity, the absence of resources product market, the lack of tradable emission permits market and no effective incentives of green production behaviors of enterprises to react up on encouraging enterprises’ development. These generate external pressure to the transformation of industrial economic growth pattern.
360° reflection-type analogue phase shifter implemented with a single 90° branch-line coupler

A small reflection-type 360/spl deg/ analogue phase shifter is realised with four varactors and a 90/spl deg/ branch-line coupler. New design formulas for the phase shift and the insertion loss are derived and applied to the circuit optimisation. The phase shifter shows a total phase shift of 380/spl deg/ and an insertion loss of 4.5/spl plusmn/0.8 dB at 10 GHz. The variation of the phase is <4/spl deg/ over the whole range of temperature from 0 to 50/spl deg/C.
Fabric Hand as Perceived by U.S. and Korean Males and Females

The purpose of this research was to explore the possibility of developing comparable sets of unipolar adjectives for consumer evaluation of fabric hand for English and Korean speakers. To better understand differences in use of adjectives, the researchers examined (a) how male and female respondents in the United States and Korea apply these adjectives and (b) their preferences for hand for a specific end use for members of the judge's own sex and for the other sex. The research included four phases: focus group interviews, word list development, trial, and final data collection. Stimuli were selected to represent shirting fabrics for U.S. and Korean males and females. Subjects were 70 Korean males, 70 Korean females, 70 U.S. males, and 68 U.S. females. Three hypotheses were examined by using analyses of variance; comments made during focus group interviews suggested interpretations of results. Sex and country interacted to affect responses to fabric hand; sex and country differences were found in fabric preferences for persons of the judges' sex and for persons of the other sex. Results provided implications for international manufacturers and retailers and for researchers using affective stimuli.
Experimental Studies and Models for Ductile Fracture in ASTM A992 Steels at High Triaxiality

AbstractThis study presents the results of experimental investigation and models for ductile fracture in the ASTM A992 structural steels subjected to high stress triaxiality. To this end, uniaxial tension tests on the notched tensile specimens are conducted, and subsequent scanning electron microscopy (SEM) studies are performed on the fractured surfaces. From this SEM analysis, the fracture initiation mechanism in ASTM A992 steels is found to be the ductile fracture; however, the fracture propagation mode can be either ductile or cleavage fracture. Nonlinear finite-element analysis of the notched specimens is carried out to obtain the stress triaxiality distributions, and the location of the peak stress triaxiality is found to be strongly correlated to the location of the ductile fracture initiation zones. Finally, two uncoupled ductile fracture prediction models, the void growth model (VGM) and the stress modified critical strain model (SMCS), are calibrated, and the model parameters are provided for A9.
Stress-laminated arches: a stronger case for timber bridges

Timber bridges have been around for a long time but are still viewed with suspicion by design engineers and the public alike. Though not as durable or strong as steel and concrete, timber is nevertheless a sustainable material in plentiful supply and can be combined with other materials to make up for its structural shortcomings. ‘Stress-laminated construction’, where short planks of low-grade timber are simply bolted together to make large flat slabs, is now a primary design option for secondary road applications in the US. This paper reports on pioneering UK research which has shown such bridges can be even stronger when built with arched rather than flat decks.
Natural frequencies measured from ambient vibration response of the arch dam of Mauvoisin

The resonance frequencies of the 250-m-high arch dam of Mauvoisin are obtained by way of ambient vibration tests. It is observed that the resonance frequencies initially increase with rising water level and then decrease with a further rise. This is linked to the two competing features of increasing entrained mass of water (reduction of the resonance frequencies) and of dam stiffening due to closing of the vertical construction joints (augmentation of the resonance frequencies). The ambient vibration test results are complemented by those obtained during earthquakes at an array of 12 accelerographs. Copyright © 2000 John Wiley & Sons, Ltd.
Identification of Suitable Limit States from Nonlinear Dynamic Analyses of Masonry Structures

Performance-based earthquake engineering, developed over the last decades for the design and assessment of other structures, can also be applied for masonry structures if the particularities of masonry are incorporated into the procedure. According to this methodology, structural performance can be assessed according to damage states which are identified through displacement/damage indicators. While various methods for the identification of limit states from the results of nonlinear static analyses exist, the identification of damage states from the results of nonlinear dynamic analyses is still uncertain. This article investigates a number of criteria allowing to identify the attainment of significant limit states from the results of time history analyses, in terms of appropriately identified response quantities. These criteria are applied to five building prototypes and their results are compared. A comparison with the limit states derived from nonlinear static analyses is also made.
Perceptions of academic quality and approaches to studying among technology students in distance education

Primary objective. To examine perceptions of academic quality and approaches to studying in students taking six technology courses by distance education. Research design. Students taking four courses received an end-of-course questionnaire. The following year, students taking all six courses received a mid-course questionnaire. Method. The Course Experience Questionnaire and the Revised Approaches to Studying Inventory were administered in a postal survey to 3539 students of the UK Open University. Outcomes and results. Across successive levels of study, students were progressively less likely to adopt a deep approach, were more likely to adopt a surface approach and rated their courses less favourably, especially with regard to the workload and materials. Between the middle and end of a course, students were more likely to adopt a deep approach and gave more positive ratings with regard to the materials and amount of choice. Conclusions. The survey instruments can be recommended as useful tools for monitoring the experiences of engineering and technology students.
A Model for Sustainable Humanitarian Engineering Projects

The engineering profession should embrace a new mission statement—to contribute to the building of a more sustainable, stable, and equitable world. Recently, engineering students and professionals in the United States have shown strong interest in directly addressing the needs of developing communities worldwide. That interest has taken the form of short-and medium-term international trips through Engineers Without Borders—USA and similar organizations. There are also several instances where this kind of outreach work has been integrated into engineering education at various US institutions such as the University of Colorado at Boulder. This paper addresses the challenges and opportunities associated with balancing two goals in engineering for humanitarian development projects: (i) effective sustainable community development, and (ii) meaningful education of engineers. Guiding principles necessary to meet those two goals are proposed.