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The purpose of this paper is to solve the problem that the location of the initiation point cannot be measured accurately in the shallow underground space, this paper proposes a method, which is based on fusion of multidimensional vibration sensor information, to locate single shallow underground sources.

First, in this paper, using the characteristics of low multipath interference and good P-wave polarization in the near field, the adaptive covariance matrix algorithm is used to extract the polarization angle information of the P-wave and the short term averaging/long term averaging algorithm is used to extract the first break travel time information. Second, a hybrid positioning model based on travel time and polarization angle is constructed. Third, the positioning model is taken as the particle update fitness function of quantum-behaved particle swarm optimization and calculation is performed in the hybrid positioning model. Finally, the experiment verification is carried out in the field.

The experimental results show that, with root mean square error, spherical error probable and fitness value as evaluation indicators, the positioning performance of this method is better than that without speed prediction. And the positioning accuracy of this method has been improved by nearly 30%, giving all of the three tests a positioning error within 0.5 m and a fitness less than 1.

This method provides a new idea for high-precision positioning of shallow underground single source. It has a certain engineering application value in the fields of directional demolition of engineering blasting, water inrush and burst mud prediction, fuze position measurement, underground initiation point positioning of ammunition, mine blasting monitoring and so on.

The purpose of this paper is to enable robots to intelligently adapt their damping characteristics and motions in a reactive fashion toward human inputs and task requirements during physical human–robot interaction.

This paper exploits a combination of the dynamical system and the admittance model to create robot behaviors. The reference trajectories are generated by dynamical systems while the admittance control enables robots to compliantly follow the reference trajectories. To determine how control is divided between the two models, a collaborative arbitration algorithm is presented to change their contributions to the robot motion based on the contact forces. In addition, the authors investigate to model the robot’s impedance characteristics as a function of the task requirements and build a novel artificial damping field (ADF) to represent the virtual damping at arbitrary robot states.

The authors evaluate their methods through experiments on an UR10 robot. The result shows promising performances for the robot to achieve complex tasks in collaboration with human partners.

The proposed method extends the dynamical system approach with an admittance control law to allow a robot motion being adjusted in real time. Besides, the authors propose a novel ADF method to model the robot’s impedance characteristics as a function of the task requirements.

The purpose of this paper is to present a method which enables a robot to learn both motion skills and stiffness profiles from humans through kinesthetic human-robot cooperation.

Admittance control is applied to allow robot-compliant behaviors when following the reference trajectories. By extending the dynamical movement primitives (DMP) model, a new concept of DMP and stiffness primitives is introduced to encode a kinesthetic demonstration as a combination of trajectories and stiffness profiles, which are subsequently transferred to the robot. Electromyographic signals are extracted from a human’s upper limbs to obtain target stiffness profiles. By monitoring vibrations of the end-effector velocities, a stability observer is developed. The virtual damping coefficient of admittance controller is adjusted accordingly to eliminate the vibrations.

The performance of the proposed methods is evaluated experimentally. The result shows that the robot can perform tasks in a variable stiffness mode as like the human dose in the teaching phase.

DMP has been widely used as a teaching by demonstration method to represent movements of humans and robots. The proposed method extends the DMP framework to allow a robot to learn not only motion skills but also stiffness profiles. Additionally, the authors proposed a stability observer to eliminate vibrations when the robot is disturbed by environment.

In Beijing, urban agriculture (UA) experienced a corkscrew development with its role changing in decades: It has evolved from the purely production mode to multi-functional urban agriculture, fulfilling both social and ecological demands. At present, the practice of UA as well as the number of rural to urban migrants is growing rapidly in peri-urban Beijing. Through Multi-stakeholder Process for Action planning and Policy Design (MPAP) methodology and four in-depth case studies, we can see that UA activities are playing very important roles in reshaping peri-urban Beijing. Socially, UA induces the emergence of new migrant communities. While migrants rebuild their social network, they are changed by the city as well, which has also changed the local community. The new comers are on their way to creating a new balance. Physically, urban and peri-urban farmland limits urban sprawl, supplies agricultural products for everyday life, and reserves urban green spaces for recreation and leisure for citizens in Beijing, which has changed the landscape and land use and land cover (LUCC) pattern greatly. Under Beijing's land policy, the concentric configuration spatial allocation through multi-functional UA is formed, which at the same time due to migrants' UA activities are creating harmful and low efficient land use pattern which should be of concern.

The purpose of this paper is to further explore the co-citation and bibliographic-coupling relationship among the core authors in the field of Chinese information science (IS), to expose research activity and author impact, and to make induction analyses about Chinese IS research patterns and theme evolution.

The research data include 8,567 papers and 70,947 cited articles in the IS field indexed by Chinese Social Sciences Citation Index from 2000 to 2009. Author co-citation analysis, author bibliographic-coupling analysis, social network analysis, and factor analysis were combined to explore co-citation and bibliographic-coupling relationships and to identify research groups and subjects.

Scholars with greatest impact are different from the most active scholars of Chinese IS; there is no uniform impact pattern forming since authors’ impact subjects are scattered and not steady; while authors’ research activities present higher independence and concentration, there is still no steady research pattern due to no deep research existing. Furthermore, Chinese IS studies can be delineated by: foundation or extension. The research subjects of these two parts, as well as their corresponding/contributing authors, are different under different views. The general research status of core authors is concentrated, while their impact is broad.

The combined use of some related methods could enrich the development and methodology research of the discipline, and the results establish a reference point on the development of IS research.

The purpose of the work is to verify the offered hypothesis and to evaluate the potential of the modern Russian entrepreneurship in economy’s informatization.

A specially developed proprietary method of evaluation of entrepreneurship’s potential in economy’s informatization and the level of its opening is used, which is created on the basis of the classical method of effectiveness evaluation. The information and analytical basis of studying the entrepreneurship’s potential in economy’s informatization is the materials of the report “The Global Information Technology Report 2016. Innovating in the Digital Economy”, prepared and presented by INSEAD, JOHNSON (Cornell University) and World Economic Forum. The offered proprietary method envisages evaluation of entrepreneurship’s potential in economy’s informatization and the level of its opening on the basis of statistical data according to four criteria: business and innovational environment, business ICT infrastructure, usage of new ICT in business, and economic consequences of using new ICT in business.

The author evaluates the entrepreneurship’s potential in economy’s informatization in modern Russia in 2016 and concludes that entrepreneurship’s potential in modern Russia is rather high, due to which high value of the index of information economy’s formation in Russia is achieved. That is, large entrepreneurship’s potential in economy’s informatization should be viewed as a precondition for information economy’s formation in modern Russia.

The author proves that entrepreneurship’s potential in economy’s informatization is an important component of the process of information economy’s formation in the economic system and can stimulate successful and quick implementation of this process or, quite on the contrary, slow down it rated, based on which it should be paid more attention.

This paper aims to study the impact of manufacturer’s upgrading strategy of durable products on the retailer’s decision on trade-in program and her decision on the secondary market.

This paper develops a channel that consists of a manufacturer and a retailer, where the manufacturer releases an upgraded product, and the retailer introduces a trade-in program for consumers, simultaneously, decides whether to enter the secondary market. These approaches are modeled through Stackelberg game.

This paper reveals that the optimal conditions for manufacturer to release upgraded products and retailer to resell used products in the secondary market, and it reveals that under what conditions it is profitable for retailer to enter the secondary market under product upgrade levels.

If the manufacturer’s upgrade level is low, it is profitable for the retailer to enter the secondary market. However, if the manufacturer’s upgrade level is high, it is unprofitable for the retailer to enter the secondary market.

In this paper, the active secondary market, upgrading of new products, consumer market segmentation and especially, the upgrade degree of new products as a function of consumer demand are considered simultaneously.

The purpose of the investigation was to research the best process of electroless nickel (EN) plating on AZ91D magnesium alloy and the performance of EN plating coating.

Through single factor test and orthogonal test, EN plating on AZ91D magnesium alloy was researched. The plating rate and porosity were analyzed. The coating appearance of EN plating coating and magnesium alloy substrate was evaluated. The electrochemical properties of EN plating coating and substrate were researched using electrochemical workstation, and their compositions and structure were examined using X-ray diffraction and scanning electron microscopy.

The results made by combination of experimental and orthogonal test showed that the best formula of EN plating was 8.8 g·L⁻¹ nickel ion, 25 g·L⁻¹ lactic acid, 28 g·L⁻¹ reducing agent, 1.8 ml·L⁻¹ corrosion inhibitor, 1 mg·L⁻¹ stabilizer, temperature at 85°C and pH value at 5.5. The plating was uniform, dense and with no cracks. The electrochemical tests showed that the corrosion resistance of EN plating was better than that of magnesium alloy substrate.

The results indicated that the corrosion resistance of magnesium alloy improved markedly after EN plating at the best formula and the plating covered magnesium alloy completely.

Targeting the common functions of the Zhejiang Library website, elderly individuals were invited to complete six experimental tasks on the improved website interfaces, and subjective data (PAD emotion scale and usability evaluation) and objective data (eye movement data) were recorded to verify the effects of graphic layout and navigation position on the information-seeking experience of elderly individuals.

This study analyzes the effect of the graphic layout and navigation position of the Zhejiang Library’s website interface on the emotional state, perceived usability and information-seeking time of elderly individuals, with the aim of providing guidance and suggestions for the elderly-oriented reform of the public library website.

The experimental results show that the graphic layout has a significant effect on the emotional state and perceived usability of elderly individuals, and the navigation position has a significant effect on the information-seeking time; the interaction between graphic layout and navigation position exerts a significant effect on the information-seeking time of elderly individuals. The eye movement data show that elderly individuals have a better information-seeking experience when the top navigation bar and image-text matched arrangement are used for the interface layout.

This study adopts a new approach combining subjective data and eye movement data to evaluate the effect of the public library website’s interface layout on the information-seeking experience for older people. The findings can provide a theoretical basis and methodological support for the elderly-oriented reform of public library websites. They can also provide scientific design suggestions for age-friendly interface layouts of other Internet products and service applications.

This paper aims to re-examine the effect of middle managers’ participation in decision-making (DM) on the innovation performance of Chinese manufacturing firms. It also testifies the intermediation channels regarding how middle managers’ participation influences firm innovation performance by testing the mediating effect.

This paper constructs a model that determines firm innovation and tests the hypotheses with econometric regressions using first-hand data from the China Employer–Employee Survey. Semiparametric and intersectional regressions are used to show how middle managers’ participation in DM influences Chinese firm innovation after controlling for the characteristics of middle manager personnel, entrepreneurs, frontline workers, firm, industry and country.

This paper empirically shows that middle managers’ participation in DM has a significantly positive effect on firm innovation. After testing the mediating effect, the findings show that the improvement of middle managers’ DM participation leads to a certain increase in technicians and a reduced dependence on government. In this regard, middle managers’ participation is complementary to the human capital of entrepreneurs.

This paper measures the degree of middle managers’ participation in DM according to four indicators. It focuses on the influence mechanisms of middle managers’ participation in DM on firm innovation performance, based on their ability to allocate external and internal resources. These findings will be useful for investigating management resource reallocation within firms for developing countries.