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The purpose of this paper was to study some effective evaluation methods for the biocide performance on sulfate-reducing bacteria (SRB) biofilm.

The most probable number method, electrochemical impedance spectroscopy (EIS) measurements, scanning electron microscopy (SEM), three-dimensional (3D) photos and epifluorescent microscopy were used in this study.

The results showed that the minimum inhibitory concentrations and minimum bactericidal concentrations of them to sessile SRB were greatly more than planktonic SRB. The EIS of the two biocides indicated that the biofilm exposed to higher concentrations of biocide were much more compact and flat, which perfectly coincided with the SEM, 3D photos and the epifluorescent microscopies.

In this paper, it, thus, appears that these methods evaluating biocide performance on the SRB biofilm were really effective by comparing the performance of bis-quaternary ammonium salt (BAQS) and tetrakis hydroxymethyl phosphonium sulfate.

Exploring the antecedents of members community participation is extremely important for virtual communities (VCs) research and practice. As an important social characteristic of individuals, social embeddedness has been proved as an important antecedent of many individual behaviors; however, few research has investigated the influence of virtual community members social embeddedness on virtual community members’ participation. To fill this gap, the purpose of this paper is to explore the relationship between social embeddedness and community participation in VCs.

This paper conducted empirical study to test the hypotheses. Based on existing scales, this research designed the questionnaire and used a web-based survey to collect the data from VCs in China. To avoid the common method bias, this study collected data at two different times. The final sample included 96 virtual community members from seven communities (community size ranging from 10 to 25) of Baidu Tieba, which is the largest Chinese online communication platform. And this paper used regression models to analysis the data.

Based on social network theory, this paper found that virtual community members’ social embeddedness in their virtual community has a curvilinear (i.e. inverted U-shaped) effect on their community participation behaviors. And members’ perceived autonomy mediates the curvilinear (i.e. reversed U-shaped) relationship between social network embeddedness and community participation. Furthermore, member instability moderates the curvilinear (i.e. inverted U-shaped) main effect, such that the curvilinear relationship is weakened when member instability is high.

Departing from previous virtual community studies that examine antecedences of participation in linear logic, this study applied social network theory to create a complex, curvilinear, moderated mediation model. The result reveals a curvilinear (i.e. inverted U-shaped) relationship between virtual community members’ social embeddedness in the virtual community and their community participation. And this study also introduce autonomy as mediator and member instability as moderator. By testing the whole model between community members’ social embeddedness and community participation, this study contributes to deepen the understanding of social embeddedness and virtual community participation.

Organizations, both large and small, are increasingly outsourcing their applications to application service providers (ASPs) for a variety of reasons such as cost reduction, shortened time‐to‐market, lack of internal expertise, and risk reduction. However, the adoption of the ASP model has not been smooth sailing for many organizations, and only a few organizations have a formal approach to making ASP outsourcing decisions. Partially to fill this void, develops a value‐driven approach to outsourcing using ASP based on outsourcing theories and the industry’s best practices. The value‐driven approach is an adaptation and extension of Simon’s decision‐making process. It is designed to guide IS managers systematically through the complex process of identifying outsourcing opportunities, evaluating the viability of using the ASP model, making outsourcing decisions, managing contractual and implementation issues, and assessing the service quality of ASP vendors. Provides important implications for research and practice. For researchers, identifies ample research opportunities in this new field. For practitioners, the value‐driven approach gives them an invaluable tool to manage today’s complex information technology outsourcing.

This chapter analyzes the technological growth of the modern Russian economy through the prism of evaluating its effectiveness from the position of costs and profits. It also determines the factors of this growth and develops recommendations for managing them in the interests of acceleration of rate and increase of effectiveness of technological growth of the modern Russian economy. While technological growth in Russia shows high effectiveness, the model of technological growth in Russia has its specifics, connected to the unconventional influence of a standard set of the factors on technological growth. The influence of the factor of the number of organizations that implement R&D is insignificant, and the influence of the number of personnel involved with R&D, volume of private expenditures for R&D, and the number of used leading production technologies is negative (reverse). We offer recommendations for increasing the effectiveness of technological growth of the modern Russian economy, which are connected to increase of the volume of state expenditures for R&D (recommended volume – USD 35.09, its growth as compared to 2018 constitutes 191.76%) and increase of the number of developed leading production technologies (recommended number of these technologies – 2350.05, its growth as compared to 2018 constitutes 62.34%).

In the last few decades, there has been growing interest in forecasting with computer intelligence, and both fuzzy time series (FTS) and artificial neural networks (ANNs) have gained particular popularity, among others. Rather than the conventional methods (e.g., econometrics), FTS and ANN are usually thought to be immune to fundamental concepts such as stationarity, theoretical causality, post-sample control, among others. On the other hand, a number of studies significantly indicated that these fundamental controls are required in terms of the theory of forecasting, and even application of such essential procedures substantially improves the forecasting accuracy. The aim of this paper is to fill the existing gap on modeling and forecasting in the FTS and ANN methods and figure out the fundamental concepts in a comprehensive work through merits and common failures in the literature. In addition to these merits, this paper may also be a guideline for eliminating unethical empirical settings in the forecasting studies.

Introduction: With the accelerated process of building metropolitans, more and more people tend to live in cities. So, to deal with this, the need has arisen to make smart everything that we have around us even when we arrived at the term of the smart city. All of this produces data we call big data that is generated by citizens.

Aim: So, cloud computing is the main idea implementation which we can use ineffective from all of these services which we call smart. And taking into account all of this, in this literature review, we have used different techniques to extract the most relevant papers on our topic. Mainly, we focus on smart cities and their taxonomy of it such as smart homes, smart buildings, traffic monitoring, security and emergencies, and so on. For a smart city, we discussed different proposed system architectures which represent the real work of researchers.

Results: In this way, we mention services that are offered and have the base services cloud services. Also, the articles we used are extracted and analysed from the most powerful and relevant databases such as IEEE, ACM, Elsevier, Science Direct, and so on. In total, we take 88 papers, and from all of these papers we have extracted 53 with different methods. This Systematic Literature Review presents building and using smart cities inside of cloud computing services.

Conclusion: However, a different implementation idea to do better life for all of us is by converting our lifestyle into a new form of living. The only form of implementation is by digitalising and implementing everything around us which means making every service in one place, where you can have access from anywhere, anytime. So, the smart city is the future.

Originality/value: This systematic literature review contributes to everyone who expresses interest to implement and provides additional evidence for existing studies in smart city patterns which used cloud services. Researchers offer various implementation forms of different models and express the impact of cloud services, especially for placements, where there are more people populated. Also, this study identifies a major weakness in existing smart city implementation by using cloud services, which have identified the main obstacles now and it needs to reanalyse the form of implementation for more complex systems in the future.

The criteria importance through intercriteria correlation (CRITIC) and range of value (ROV) combined methods were used to determine a single index for all multiple responses.

This paper used cold metal transfer (CMT) and pulse metal-inert gas (MIG) welding processes to study the weld-on-bead geometry of AA2099-T86 alloy. This study used Taguchi's approach to find the optimal setting of the input welding parameters. The welding current, welding speed and contact-tip-to workpiece distance were the input welding parameters for finding the output responses, i.e. weld penetration, dilution and heat input. The L9 orthogonal array of Taguchi's approach was used to find out the optimal setting of the input parameters.

The optimal input welding parameters were determined with combined output responses. The predicted optimum welding input parameters were validated through confirmation tests. Analysis of variance showed that welding speed is the most influential factor in determining the weld bead geometry of the CMT and pulse MIG welding techniques.

The heat input and weld bead geometry are compared in both welding processes. The CMT welding samples show superior defect-free weld beads than pulse MIG welding due to lesser heat input and lesser dilution.

Ti-Al composite plates have been used in aerospace and other important fields for specific purposes in recent years. However, relatively few studies have concentrated on Ti-Al additive manufacturing because during additive manufacturing process the local fusion and mixing of Ti/Al are inevitable. These areas where Ti and Al are mixed locally, especially interface, could easily generate high residual stresses and cracks. This study aims to manufacture Ti-Al functionally graded material and investigate the interaction of interface.

In this study, Ti6Al4V/AlSi10Mg functionally graded materials were fabricated by laser based directed energy deposition (L-DED) and a strategy using V interlayer to relieve interfacial stress was investigated.

The area between the two materials was divided into transition zone (TZ) and remelting zone (RZ). The phase distribution, microstructure and micro-Vickers hardness of the TZ and RZ were investigated. Typical intermetallic compounds (IMCs) such as TiAl3, Ti3Al and Ti5Si3 were found in both composites. The addition of V interlayer promoted the homogenization of IMCs near interface and led to the formation of new phases like V5Si3 and Al3V.

The solidification process near the interface of Ti-Al functionally graded material and the possible generation of different phases were described. The result of this paper proved the feasibility of manufacturing Ti-Al functionally graded material by L-DED.

This paper aims to investigate magnetic field anneal in micro-patterned Co-based amorphous ribbon on giant magneto-impedance (GMI) effect enhancement.

The amorphous ribbons were annealed in transverse and longitudinal magnetic field. The influence of different field annealing directions on GMI effect and impedance Z, resistance R and reactance X with a series of line width have been deeply analyzed.

In comparison with GMI sensors microfabricated by unannealed and transversal field annealed ribbons, GMI sensor which was designed and microfabricated by longitudinal field anneal ribbon performs better. The results can be explained by the domain wall motion and domain rotation during annealing process and the geometric structure of Co-based GMI sensor. In addition, shrinking the line width of GMI sensor can promote GMI effect significantly because of the effect of demagnetizing field, and the optimum GMI ratio is 209.7 per cent in longitudinal field annealed GMI sensor with 200 μm line width.

In conclusion, annealing in longitudinal magnetic field and decreasing line width can enhance GMI effect in micro-patterned Co-based amorphous ribbon.