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Deriving the gravitational effective action directly from exact renormalization group is very complicated, if not impossible. Hence, to study the effects of running gravitational coupling which tends to a non-Gaussian UV fixed point (as it is supposed by the asymptotic safety conjecture), two steps are usually adopted. Cutoff identification and improvement of the gravitational coupling to the running one. As suggested in Ref. 1, a function of all independent curvature invariants seems to be the best choice for cutoff identification of gravitational quantum fluctuations in curved space–time and makes the action improvement, which saves the general covariance of theory, possible. Here, we choose Ricci tensor square for this purpose and then the equation of motion of improved gravitational action and its spherically symmetric vacuum solution are obtained. Indeed, its effect on the massive particles’ trajectory and the black hole thermodynamics is studied.

With the rapid development of online e-commerce, traditional collaborative filtering algorithms have the disadvantages of data set reduction and sparse matrix filling cannot meet the requirements of users. This paper takes handicrafts as an example to propose the design and application of handicraft recommendation system based on an improved hybrid algorithm. Based on the theory of e-commerce system, through the traditional collaborative filtering algorithm of users, the personalized e-commerce system of hybrid algorithm is designed and analyzed. The personalized e-commerce system based on hybrid algorithm is further proposed. The component model of the business recommendation system and the specific steps of the improved hybrid algorithm based on user information are given. Finally, an experimental analysis of the improved hybrid algorithm is carried out. The results show that the algorithm can effectively improve the effectiveness and exemption of recommending handicrafts. What’s more, it can reduce the user item ratings of candidate set and improve accuracy of the forecast recommendation.

The end users' expectations for the software services are increasing. With new technologies, e.g. cloud computing and software as a service trend, the quality of the services through a full product life cycle, together with the cost of services, are key factors in making the competitive advantage in new markets. In most cases in today's business, there is always the Service Level Agreement (SLA) that has to be maintained as well. Therefore, there is a clear need for taking into consideration the complexity of the programmed solution, that is the basis of the given service, probability of an error occurrence, and all costs that will be associated with operating the service. In this paper, the important elements of the quality of the software that is considered a service to a business function are analyzed. The proposal of the six step method, which could be utilized in continuous quality improvements, is given. With this method, it is possible to better understand the root reasons for a specific service's behavior. Understanding service behavior is the key prerequisite for service improvement. The method encapsulates systematic approach in comparative analysis of the defined parameters of each service, with the same parameters of other services that belong to the same rank. These relative comparisons are proposed to be done in drill-in cycles until getting to the point of clear understanding of what makes one service better than the other and vice versa, in the given business environments. Each single conclusion on each level of cycled comparative measurements would trigger improvement action at that level. This method also provides the management with better tools to perform adequate human resources capacity planning for each software service for the given time frame. An example of the method utilization on one selected use case is given as well.

The BOOTSTRAP approach to software process assessment and improvement offers a methodology which can be suitably used with different types of the software process and products, and with different software producing organization structures and sizes. The approach is supported by cumulative data about the software industry as a whole as well as its individual sectors. At the same time BOOTSTRAP is based on the ISO 9000 series quality standards and appropriately general software project management standards (ESA-PSS-05), as well as is related to such defacto maturity standards as SEI's CMM. More granularity in expressing capability (in terms of scale and multidimensionality) makes BOOTSTRAP particularly suitable for process improvement. While having established position in Europe and participating in such wider standardization efforts as ISO/SPICE, it is important for BOOTSTRAP to look for comparisons of assumptions and results elsewhere. This paper presents the BOOTSTRAP methodology and and in conclusions brings forward some topics that may constitute a cultural interface orspecific boundary conditions between different software process assessment and improvement approaches.

The mature and scale utilization of renewable energy is restricted by the deficient efficiency of latent heat storage (LHS) technology. To address this, an innovative Vicsek fractal fin is first proposed herein for the heat charging/discharging rate enhancement. The phase transition behavior and thermal characteristics of the innovative LHS unit are solved numerically and compared to the traditional one, employing the enthalpy–porosity algorithm and a two-dimensional transient model. The results indicate that Vicsek fractal fins remarkably promote the thermal efficiency of LHS units. Compared to the traditional LHS units, innovative LHS units with Vicsek fractal fins, respectively, reduce the melting/solidification duration by 16.1% and 28.7%. The melting process is divided into early thermal conduction, subsequent convective thermal transport, and later thermal conduction, while solidification processes are dominated by the initial natural convection and the subsequent continuous heat conduction. Moreover, the impact of free convection is higher on melting processes than on solidification processes. Importantly, the efficient heat transfer path of Vicsek fractal fins allows the inherent natural convection suppression to be much weaker than the improvement level of heat transfer efficiency, facilitating the interstitial thermal transport between the phase change material (PCM) and fins and improving the overall temperature uniformity of LHS units.

The venation-finned porous network has been demonstrated as a promising method to maximize the thermal transport access. To improve the heat storage efficiency, an innovative venation-finned porous network is employed here to enhance the melting performance of phase change materials (PCMs). The venation-finned porous network is quantitatively described by Murray’s law and Voronoi method, and a modified thermal lattice Boltzmann model of PCM melting processes in a square cavity is developed and numerically analyzed to optimize the venation-finned porous network. The melting performance of composite PCMs with three configurations (venation fin, porous network and venation-finned porous network) are compared and analyzed. Moreover, the effects of branching angle and Murray coefficient on melting performance are comprehensively studied. It indicates that venation-finned porous network is favorable to melting performance improvement due to venation’s inherent efficient heat transfer paths. Compared to venation fins and porous networks, the melting duration time of venation-finned porous networks is reduced by 78.4% and 21.4%, respectively. Furthermore, the branching angle of 45${}^{\circ }$ and Murray coefficient of 3 are suggested for maximizing the melting efficiency. Importantly, the melting mechanism is conduction and convective conjugated heat transfer in composite PCMs with venation fins, however, it is dominated by heat conduction for those with porous networks or venation-finned porous networks.

This paper uses Theory of Constraints (TOC) improvement questions to measure how employees' demographics influence their adoption of various Information Technology Equipments (ITEs) in organisations. Survey questions in the form of a Likert scale are prepared to address these possible effects. The number of total participants was 216 and they were from two universities: Argosy University, Atlanta campus; and Brigham Young University, Provo campus. The research question for this study asked how the factors of age, gender, race, and education level positively or negatively influence employees' attitudes toward ITE adoption at their place of employment. A Pearson product-moment correlation coefficient was computed to assess the relationships and the Kruskal–Wallis and the Mann–Whitney U tests were used to compare the independent groups. The results suggested that there was a correlation among age, race and education level and indicated that age negatively correlates with employees' level of comfort with ITE use. There was a statistically significant difference at the 0.01 level between White and Black participants.

The secure quantum sealed-bid auction protocol [Mosayeb Naseri, Opt. Commun.282 (2009) 1939] is revisited. It is found that, utilizing intercept-measure-resend attacks, any evil bidder can make the auction aborted without being detected by the auctioneer. Further, if the evil bidder succeeds to be the first bidder, then he/she can win conclusively in the auction. To prevent such attacks, some defence strategies are adopted in the qubit distribution stage and the channel security check stage respectively and the original protocol is therefore modified somewhat.

A quantum private comparison (QPC) protocol based on W states [W. Liu et al., Opt. Commun.284, 3160 (2011)] has pointed out there is a flaw of information leak [Y. B. Li et al., Eur. Phys. J. D.66, 110 (2012)]. In order to solve the problem, a special kind of W-class state is introduced, and its construction framework of quantum circuits is sketched. Based on this kind of W-class states, an improvement on Liu et al.'s protocol is presented. Analysis shows the improvement can not only hold the characteristics of original protocol, but also avoid the information leak that Li et al. pointed out.

The ISO56002 international standard for managing innovation systems was published in 2019. In this paper, we review the rationale, the key features, and the evidence base for this new standard. The primary objective of the standard is to promote the professionalisation of the field by providing a framework for management and organisational practice. The standard was developed by a wide range of stakeholders, including consultants and professional associations, and therefore features most of the elements we would expect from such a high-level, generic approach: strategy, organisation, leadership, planning, support, process, performance evaluation, and improvement. We examine the empirical base for each of these components in this paper. We also identify some critical shortcomings, such as the implicit adoption of a linear model, lack of specific tools to support practice, or any significant variation in application by sector or context. Finally, we recommend how the standard could be improved and implemented in practice.

Simulations of the gas fluidization of a cohesive powder were performed using the Stokesian Dynamics method and an agglomeration-deagglomeration model to investigate methods of improving the fluidizability of fine powders. Three techniques (a) high gas velocity (b) vibration-assisted fluidization and (c) tapered fluidizer were used in the simulations which provided detailed information on the bed microscopy such as the motion of 100 particles in a fluidizing vessel along with the formation and destruction of cohesive bonds during collisions. While all three techniques were found to effectively improve the fluidizability of a strongly cohesive powder, we suggest a combination of high velocity fluidization assisted by external vibration of the fluidized bed to minimize entrainment of particles.

The COVID-19 disease broke out globally, bringing great challenges to public health security and increasing the difficulties in constructing ecological civilization governance system. Under the leadership of the Central Committee of the Communist Party of China with Comrade Xi Jinping at its core, the Chinese Government and people have fought against the disease with courage and put people’s health and safety first. Through hard work, China has made achievements in controlling the COVID-19 pandemic and accelerated the restoring of work and life back to normalcy. While continuing to control the pandemic domestically, China promotes the building of a human community with shared destiny, and plays an active role in promoting global cooperation in public health, contributing extraordinarily to global public health and world economy. Guided by Xi Jinping’s Thought of Ecological Civilization, China has endeavored for modernization characterized by harmonious coexistence between man and nature. In response to the current crisis in public health and the challenges facing human–nature harmony thus incurred, the Editorial Department of Chinese Journal of Urban and Environmental Studies has co-hosted a seminar with CASS Thinktank for Eco-civilization Studies, aiming at brainstorming on and enhancing faith in continuing the building of an ecological civilization after completing the construction of a moderately well-off society in all respects. This paper intends to call for other countries to exchange and cooperate in building ecological civilization and building the world into a beautiful home for all.

The main objective of this laboratory project is to investigate the effectiveness of using polyamide grout injection on sand improvement. Soil samples with different dry densities in their loose, medium and dense state (cylindrical shaped) with 5cm diameter and 10cm height are subjected to polyamide injection. In order to investigate the grout injection effect on soil's strength, the specimens are subjected to one dimensional unconfined compression tests. We know that polyamide doesn't mix with water and we should mix it with citric acid. It has been observed that by increasing the polymer percent in polymer-water-citric acid mixture grout, the soil compressive strength and elastic modulus has been improved significantly. In general denser sands presented higher compressive strength and elastic modulus in comparison with looser ones in same polymer percents.

This paper describes the identity-based encryption scheme's basic procedures and algorithms, and briefly introduces the mathematical principles of elliptic curve, which is the mathematical ground for the algorithm, and the method of selecting the appropriate elliptic curve. It also discusses the constraints of parameters on algorithm implementation and the selection of algorithm. In terms of efficiency, security, key escrow, and key update, this paper explores the problems in IBE encryption scheme, and proposes some suggestions for the improvement of algorithm, so that the identity-based encryption scheme applies to the actual environment better.