Engineering Features Research Articles

Exploration of the antibiotic resistome in a wastewater treatment plant by a nine-year longitudinal metagenomic study

The spread of antibiotic resistance genes (ARGs) is a growing global problem. Activated sludge (AS) in wastewater treatment plants (WWTPs) has been proposed as a hotspot for ARGs. However, few studies have been conducted to uncover the temporal dynamics of the resistome of AS in WWTPs by long-term longitudinal sampling. In this study, we quantified ARGs and identified their host microbiome in a Hong Kong WWTP in 97 monthly AS samples spanning 9 years. Throughout this analysis, we demonstrated that both the abundance and structures of the resistome changed significantly every two to three years, implying that there was a successive selection of resistomes in the AS system over the study period. The detection of genes of antibiotic-resistant pathogens that are emerging major threats to public health in the AS samples, including mcr, CRE (carbapenem-resistant Enterobacteriaceae) and MRSA (methicillin-resistant Staphylococcus aureus)-related genes, highlight the role of WWTPs as reservoirs of ARGs. In addition, the core resistome (abundant and persistent genes) in AS were found to overlap with those in other ecosystems such as urban sewage, livestock feces, and fishpond sediments, revealing the broad dissemination of ARGs in WWTPs and other environments. Annual variation of resistomes were explained via structural equation modeling (SEM), which deciphered the structural linkages of determining factors such as the operational parameters, microbial community composition and horizontal gene transfer (HGT). Specifically, potentially relevant antibiotic resistance bacteria (ARBs) were explored and discussed based on assembly-based analyses and network correlations. Moreover, consistent with the clear relationship between resistomes and mobile genetic elements (MGEs), it was found that there was a relatively high potential for gene exchange in AS in comparison with soil genomes, which could be explained by the engineering features of WWTPs. Based on these findings, longitudinal monitoring of WWTPs is warranted for risk assessment to reveal emerging ARGs, resistome evolution, correlations with ARBs, and the potential for spread in downstream environments and concomitant exposure risks for humans.

Representation of Information about Part on The Basis of Its Engineering Features

Design stage of production processes for machining of parts is a nontrivial task, and technologists face considerable difficulties while selecting the best solution. Aiming at better selection of alternatives, it is important to apply intelligent systems to design production processes. Ontological model of information representation about production process is described using attribute graphs, which allows analyzing the form and spatial relationships between the structural elements of objects, and reduces the scope of interpretation of concepts and the number of interpretive functions.

Principles of MSW Landfill Sites’ Placement Depending on Geological and Hydrogeological Conditions of Territories (Based on Moscow Region)

More than 31 billion tons of unutilized waste have accumulated in Russia, and this amount is increasing every year. The dump sites’ locations require profound scientific analysis. When choosing areas for landfill sites with minimal environmental damage to surrounding areas, it is necessary to consider the following aspects: the degree of suitability of natural conditions, the engineering and geological features of the territories, including the lithological, soil, hydrological and hydrogeological, geofiltration conditions of territories, as well as the presence of settlements and sanitary zones around them, etc. At present, the choice of sites for landfills is carried out without engineering and geological surveys, without taking into account the presence of geochemical barriers and the depth to groundwater. The negative impact on the environment of MSW landfills, the design of which was carried out without taking into account the geological structure and hydrogeological conditions of the territories where they were located, was considered.

Analysis of short-to-long term heat flow in GSHP systems based on heat pump power

This paper presents a semi-analytical model based on the spectral element method for three-dimensional, short-to-long term heat flow in multiple borehole, multilayer ground source heat pump systems. The model is distinguished by its computational technique for expressing the input signal at the boundary of the borehole heat exchanger, giving rise to two important engineering features. First, the calculation can be conducted from seconds to years in a single run. This is achieved by discretizing the input signal at the inlet boundary of the borehole heat exchanger using a tailored fast Fourier transform with multiple time-stepping algorithm. Second, the calculation can be conducted using a Neumann boundary condition, instead of the commonly utilized Dirichlet boundary condition. This is achieved by mathematically relating the heat pump power to the heat flux at the inlet of the borehole heat exchanger, allowing direct use of the heat pump power signal as input instead of the inlet temperature. These features make the model computationally efficient that can readily be utilized for system design and included in inverse calculations. The two features are discussed in detail, verified against experimental measurements, and their functionality is highlighted by numerical examples.

Deformation of cantilever foundation pit engineering in sand ground: centrifuge model test

A centrifuge model test was conducted to investigate the excavation-induced deformation characteristics of the foundation pit engineering in sand ground. Laser displacement sensors (LDSs) and the particle image velocimetry (PIV) technology were jointly used to obtain the horizontal deflection (δH) of the retaining wall and ground surface settlement (δV), and the relationship between δH and δV. Test results show that the profile of δV is a spandrel type with the maximum values (δVm) close to the wall, which is consistent with Peck’s result. While, the profile of the retaining wall deflection is a straight line with the maximum values (δHm) at the top. The δVm is equal to 1.05∼1.75 δHm for the cantilever foundation pit engineering in sand ground. Although the deformation obtained by PIV method is smaller than that obtained by LDSs because of the inevitable boundary effect of the model box, PIV is an effective method to get the deformation characteristic in the deep zone.

A Study on Petrochemical Engineering Knowledge

This study is based on the characteristics of petrochemical engineering; in it, the basic properties and characteristics of petrochemical engineering knowledge are described. The petrochemical engineering knowledge system structure and knowledge cluster are mainly introduced. The study is conducted from a philosophical point of view to analyze and develop a conception on the practice of petrochemical engineering knowledge along with the development of its industry, and forms a comprehensive, clear-cut, and well-structured knowledge system.

Teaching Reform of “Engineering Chemistry” for Mechanical Electronic Engineering Specialty

“Engineering Chemistry” is a compulsory course designed for non-chemical specialty. The course in Guangdong University of Technology aims to impart students an in-depth knowledge of various aspects of chemistry as applied to engineering. However, in teaching practice for mechanical electronic engineering specialty students, the course was found some problems, such as limited teaching hours, too many contents, little connection with engineering application, and low interests from the students. According to the requirements of mechanical electronic engineering specialty, combining the knowledge of engineering chemistry and the professional features of mechanical electronic engineering, the reforms of teaching contents, teaching methods, assessment methods of the “Engineering Chemistry” course were effectively explored.

Exploration on the Construction of Industrial Colleges of Local Normal University

Due to the lack of engineering application-oriented research ability in local normal universities, and the lack of service industry enterprises or local economic and social development experience, how to establish industrial colleges has become the current problem that some local normal universities need to solve. Based on the existing practice of colleges and universities, this paper analyzes the operation mode of industrial colleges, and then puts forward a new mode for the establishment and operation of industrial colleges according to the weak characteristics of science and engineering in local normal colleges, to improve the quality of talent cultivation in normal universities.

Mindful Engineers in Sustainable Engineering

According to the Encyclopadia Britannica, the establishment of the Royal Society of London for Improving Natural Knowledge (Royal Society), the "oldest national scientific society in the world," was on November 28, 1660. In 1818, the Institution of Civil Engineers (ICE), the first professional engineering body, was also set up in London. Ten years later King Georges IV granted ICE its Royal Charter. Throughout the past 200 years, the world, and Western societies in particular, have experienced deep social changes. The engineering profession has not been an exception, and today its ethos is much broader and complex than the roots and conditions that were found at its origins. What elements are required for professional self-awareness in 21st century engineers? Our goal here is to outline these potential characteristics of contemporary engineering.

One for All: Neural Joint Modeling of Entities and Events

The previous work for event extraction has mainly focused on the predictions for event triggers and argument roles, treating entity mentions as being provided by human annotators. This is unrealistic as entity mentions are usually predicted by some existing toolkits whose errors might be propagated to the event trigger and argument role recognition. Few of the recent work has addressed this problem by jointly predicting entity mentions, event triggers and arguments. However, such work is limited to using discrete engineering features to represent contextual information for the individual tasks and their interactions. In this work, we propose a novel model to jointly perform predictions for entity mentions, event triggers and arguments based on the shared hidden representations from deep learning. The experiments demonstrate the benefits of the proposed method, leading to the state-of-the-art performance for event extraction.

Evaluation of Engineering Properties of Calcium Sulfoaluminate Cement-based Concretes Reinforced with Different Types of Fibers.

Calcium sulfoaluminate (CSA) cement has recently gained increased attention due to its lower amount of CO2 emissions, as compared to that of the ordinary Portland cement (OPC). This paper evaluates the impact of different types of fibers on the engineering features of CSA-based concretes at different water-cement ratios of 0.35 and 0.28. In this study, metallic fibers including double hooked-end steel fibers and hooked-end steel fibers, and non-metallic fibers (i.e., polyvinyl alcohol (PVA) fibers) were utilized at fiber content of 1%. The mechanical properties of concretes were assessed at different curing ages. Dimensional stability of the concrete mixes was also examined. The morphology of the fractured specimens was studied by using the SEM method. The results indicate that the engineering properties of concrete were improved by introducing fibers to the concrete, irrespective of fiber type. The results show that DHE steel fiber has an important effect on the flexural performance of CSA cement-based concretes and results in deflection-hardening behavior. It was observed that fibers and particularly PVA fibers cause a decrease in shrinkage deformation. Microstructure tests demonstrate that prismatic ettringite is the main hydration product of CSA cement-based concrete. The SEM observation also confirms that the inclusion of CSA cement in concrete improves the cohesiveness between the fibers and cement matrix.

Tissue Engineering for Clean Meat Production

Increasing public awareness of foodborne illnesses, factory farming and the ecological footprint of the meat industry, has generated the need for animal-free meat alternatives. In the last decade, scientists have begun to leverage the knowledge and tools accumulated in the fields of stem cells and tissue engineering towards the development of cell-based meat (i.e., clean meat). In tissue engineering, the physical and biochemical features of the native tissue can be mimicked; cells and biomaterials are integrated under suitable culture conditions to form mature tissues. More specifically, in skeletal muscle tissue engineering, a plurality of cell types can be co-cultured on a 3D scaffold to generate muscle fibers, blood vessels and a dense extracellular matrix (ECM). This review focuses on tissue engineering of skeletal muscle and the adjustments needed for clean meat development. We discuss the skeletal muscle structure and composition, and elaborate on cell types from farm animals that have the potential to recapitulate the muscle ECM, blood vessels, muscle fibers and fat deposits. We also review relevant biomaterials, primarily for fabricating scaffolds that can mimic the intramuscular connective tissues, as well as gene expression studies on the biological pathways that influence meat quality.

3D Facial Expression Recognition for Defining Users’ Inner Requirements—An Emotional Design Case Study

This study proposes a novel quality function deployment (QFD) design methodology based on customers’ emotions conveyed by facial expressions. The current advances in pattern recognition related to face recognition techniques have fostered the cross-fertilization and pollination between this context and other fields, such as product design and human-computer interaction. In particular, the current technologies for monitoring human emotions have supported the birth of advanced emotional design techniques, whose main focus is to convey users’ emotional feedback into the design of novel products. As quality functional deployment aims at transforming the voice of customers into engineering features of a product, it appears to be an appropriate and promising nest in which to embed users’ emotional feedback with new emotional design methodologies, such as facial expression recognition. This way, the present methodology consists in interviewing the user and acquiring his/her face with a depth camera (allowing three-dimensional (3D) data), clustering the face information into different emotions with a support vector machine classificator, and assigning customers’ needs weights relying on the detected facial expressions. The proposed method has been applied to a case study in the context of agriculture and validated by a consortium. The approach appears sound and capable of collecting the unconscious feedback of the interviewee.

Research Note: Low‐frequency pneumatic seismic sources

ABSTRACTPneumatic seismic sources, commonly known as airguns, have been serving us well for decades, but there is an increasing need for sources with improved low‐frequency signal and reduced environmental impact. In this paper, we present a new pneumatic source that is designed to achieve these goals by operating with lower pressures and larger volumes. The new source will release more air creating larger bubbles with longer bubble periods than airguns. The release of the air will be tuned so that the rise time will be longer and the sound pressure level and its slope will be lower. Certain engineering features will eliminate cavitation. Larger bubbles increase low‐frequency content of the signal, longer rise times decrease mid‐frequency content and the elimination of cavitation reduces high‐frequency content. We have not yet built a full‐scale version of the new source. However, we have manufactured a small‐scale low‐pressure source incorporating most of the engineering features, and tested it in a lake. Here, we present the lake data that, as expected, show a significant reduction in the sound pressure level, increase in rise time, decrease in slope and decrease in high‐frequency content while maintaining the same low‐frequency content when the source prototype is operated at low pressure compared with high pressure. Synthetic data produced by numerical modelling of the full‐scale proposed pneumatic source suggest that the new source will improve the low‐frequency content and can produce geophysically useful signal down to 1 Hz.

Effect of reactor operator intervention during unprotected LOFA in a typical MTR

Abstract The main objective for reactor engineering and inherent safety features is to keep the nuclear fuel in a thermally safe condition with enough safety margins during all operational states (normal-abnormal and accidental states). In this work, an accident analysis of the unprotected loss of flow transient in a typical material test reactor is presented. The effect of reactor operator intervention during the accident in case of manually triggering the shutdown system at different flow coast down ratios is studied. Flow trip scenarios are compared for flow trip ratios of 14, 15, 20, 30, 40, 50 and 60 %. The calculations were performed with the nuclear reactor analysis code PARET. The reactor stability region is described in terms of initial reactor power, core inlet temperature, and power peaking factor.

Characteristics of regional international engineering contracting market of the Belt and Road

With the implementation of the Belt and Road, international contractors face more opportunities and challenges. Based on the Engineering News-Record data, this paper analyzes the current situation of the international engineering contracting market in the region of the Belt and Road and uses the cluster analysis to conduct research on the leading international contractors in the region of the Belt and Road. Then the differences of the industry and contractors characteristics in different regional markets are confirmed. Finally, proposals are put forward for the contractors to develop regional market of the Belt and Road.

Numerical Analysis of Deep Foundation Pit Excavation under Complex Beam Support

With the deepening of people’s understanding of foundation pit engineering, people pay more and more attention to the three-dimensional characteristics of foundation pit engineering, and the continuous development of computer technology makes it possible to carry out complex three-dimensional finite element analysis of foundation pit. The three-dimensional space finite element of foundation pit is a whole structure that regards all supporting systems and vertical retaining structures as a coordinated work, which can simulate various construction conditions and calculate the internal force and deformation of each component under each working condition. This whole calculation method can also take into account the influence of the deformation of the previous working condition through the life and death technique of the unit, so that the calculation model is basically consistent with the actual situation.

Research on Overhead Line Cost Prediction Based on Index Construction

In order to meet the growing demand of the society for electric power, the construction of electric power infrastructure is constantly carried out. However, investment in construction and cost control are particularly important. Because of its own characteristics, overhead line project cost control management is difficult to carry out. According to the characteristics of overhead line engineering, this paper constructs an overhead line engineering cost index system composed of 24 indexes including voltage grade from three aspects: technical conditions, engineering quantity attribute and cost attribute. Combining with the actual data of the completed project, the BP neural network algorithm is used to predict the static investment of the project. The accuracy of the prediction model reaches 99.9%. This verifies the rationality and comprehensiveness of the overhead line project cost index system constructed in this paper, and provides reliable guidance for the overhead line project cost management.

Ambipolar SB-FinFETs: A New Path to Ultra-Compact Sub-10 nm Logic Circuits

Ultracompact sub-10-nm logic gates based on ambipolar characteristics of Schottky-barrier (SB) FinFETs and gate workfunction engineering (WFE) approach are introduced. Novel logic gate designs are proposed using WFE, whereby adjustment of workfunction in the contacts as well as two independently biased FinFET gates leads to an unprecedented degree of freedom for logic functionality that has not been explored before. The use of SB contacts, along with the high-k gate dielectric and ultrathin body, bestows a high-degree of short-channel immunity to the SB-FinFETs with ambipolar current–voltage characteristics down to 5 nm. The unique trait of the proposed novel logic gates is to lower CMOS transistor count by 50% and hence reduce overall area and power dissipation significantly. To illustrate this potential, an entirely novel conjugate (n/p channel) CMOS pass-gate transistor that can function as a two-transistor (2T) XOR and minimalist 2T NAND/NOR gates is designed and verified with TCAD simulations. Depending on the gate designed, TCAD simulations indicate that judicious choice of gate workfunctions between 3.7 and 5.2 eV can lead to CMOS logic gates with a power–delay product (PDP) at ${5}\times {10}^{-{18}}$ J level with immunity to ±0.1-eV workfunction variations. It is shown that WFE in independent-gate SB-FinFETs can lead to ultracompact logic circuits with 50% reduction in area and up to 10 times reduction in power, without significant degradation to overall PDP performance due to slower switching response compared with the conventional designs with p-n junction FinFET counterparts.

Study on Hospital Medical Information Engineering

On the base of the current status of hospital medical information engineering, this paper analyzes some major problems existing in computer hardware, and puts forward some plans and reform measures in connection with the characteristics of medical information engineering. Because the application of electronic information engineering in hospitals is perfect and comprehensive, and there is no corresponding management training, so that the management personnel do not have the information technology and skills required by the application of electronic information engineering, the training of relevant personnel should be strengthened.