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Coal and power generation are related upstream and downstream industries. Coal price marketization and electricity price regulation have caused the price of coal to be sensitive to the benefits of generators. The paper aims to discuss these issues.

As a financial tool, contracts for differences can both help balance interests and reduce risks caused by spot price fluctuation. This thesis regards coal demand as a triangular fuzzy stochastic variable while directing a levelling consideration towards risk returns for coal and power enterprises that are involved in coal generation contracts for differences. Risk and benefit measurement models were established between coal suppliers and power generators, and risk and benefit balance optimization models for contract negotiation were constructed.

A numerical example showed that the above models can be effectively used to avoid the risks of coal-electricity parties.

This thesis regards coal demand as a triangular fuzzy random variable while directing a levelling consideration towards the risk return to coal and power enterprises that are involved with coal generation contracts for differences. The features of this thesis are the following: demand information is regarded as a fuzzy random variable instead of a random variable. With historical data, sales experience and increasingly clear macro-economic conditions, coal and power enterprises are able to make a fuzzy decision – to a certain extent – when the transaction approaches. Accurate market information enables the supply chain system to satisfy the clients’ needs better, improve the profit level or avoid severe financial damages; by developing a feasible set of contracts for different parameters, it is possible to estimate whether the price difference enables supply chain coordination, requires changes or gives accounts to all involved parties of the supply chain; and without the assumption that the traditional M-V rule is unfavourable to decision makers, this thesis proposes the prospect M-V rule, which involves decision makers’ projections of future coal generation prices and enables wide applicability of the response method to contracts for differences.

This study aims to obtain the speed and angle during safe and comfortable standing of elderly people. With the advancement of society, it is becoming increasingly difficult for the elderly to sit-to-stand (STS) independently and comfortably in a safe and comfortable manner. Safety is essentially a prerequisite for the elderly to achieve a comfortable STS. The speed, angle and power of the STS process can all affect safe STS. From the standpoint of health-care delivery and administration, comfortable STS can be realized easily by addressing the safety issues during STS.

This paper summarizes the research progress on speed and angle during safe and comfortable standing of older people. The authors analyzed the speed and angle of the STS using the Vicon optical gait acquisition system and plantar pressure sensor to find the appropriate angle and speed thresholds.

The center of gravity movement is a prerequisite for the elderly to achieve a comfortable STS. The authors found that the standing speed during the STS process should not be higher than 103.8 mm/s so that the elderly can stand comfortably and safely (safe and dangerous speeds are 72.8 mm/s and 125.2 mm/s). The limitations of waist angle, waist angle speed and the acceleration are also obtained.

This paper analyzes and summarizes the research status of speed and angle during safe and comfortable standing of elderly people, which is essentially a prerequisite for the elderly to achieve a comfortable STS. These results can lay the foundation for the development of assistive devices and related technologies that meet the needs of older adults.

This paper aims to find proper technological parameters of low-temperature joining technique by silver sintering to eventually use this technique for reliable electronic packaging.

Based on the literature and author’s own experience, the factors influencing the nanosized Ag particle sintering results were identified, and their significance was assessed.

It has been shown that some important technological parameters clearly influence the quality of the joints, and their choice is unambiguous, but the meaning of some parameters is dependent on other factors (interactions), and they should be selected experimentally.

The value of this research is that the importance of all technological factors was analyzed, which makes it easy to choose the technological procedures in the electronic packaging.

This paper aims to use nano-silver paste to design a new bonding method for super-large-area direct-bonded-aluminum (DBA) plates. It compared several frequently used bonding methods and proved the feasibility of an optimized low-pressure-assisted double-layer-printed silver sintering technology for large-area bonding to increase the thermal conductivity of power electronic modules with high junction temperature, higher power density and higher reliability.

The bonding profile was optimized by using transparent glasses as substrates. Thus, the bonding qualities could be directly characterized by optical observation. After sintering, the bonded DBA samples were characterized by nondestructive X-ray computed tomography system, scanning electron microscopy equipped with an energy dispersive spectrometer. Finally, bonding stress evolution was characterized by shear tests.

Low-pressure-assisted large-area double-layer-printed bonding process consisting of six-step was successfully developed to bond DBA substrates with the size of 50.8 × 25.4 mm. The thickness of the sintered-silver bond-line was between 33  and 74 µm with the average porosity of 12.5 per cent. The distribution of shear strength along the length of DBA/DBA bonded sample was from 9.7  to 18.8 MPa, with average shear strength of 15.5 MPa. The typical fracture primarily propagated in the sintered-silver layer and partially along the Ni layer.

The bonding stress needs to be further improved. Meanwhile, the thermal and electrical properties are encouraged to test further.

If nano-silver paste can be used as thermal interfacial material for super-large-area bonding, the thermal performance will be improved.

The paper accelerated the use of nano-silver paste for super-large-area DBA bonding.

The proposed bonding method greatly decreased the bonding pressure.

The purpose of this paper is to establish a two-stage grey cloud clustering model to assess the drought risk level of 18 prefecture-level cities in Henan Province.

The clustering process is divided into two stages. In the first stage, grey cloud clustering coefficient vectors are obtained by grey cloud clustering. In the second stage, with the help of the weight kernel clustering function, the general representation of the weight vector group of kernel clustering is given. And a new coefficient vector of kernel clustering that integrates the support factors of the adjacent components was obtained in this stage. The entropy resolution coefficient of grey cloud clustering coefficient vector is set as the demarcation line of the two stages, and a two-stage grey cloud clustering model, which combines grey and randomness, is proposed.

This paper demonstrates that 18 cities in Henan Province are divided into five categories, which are in accordance with five drought hazard levels. And the rationality and validity of this model is illustrated by comparing with other methods.

This paper provides a practical and effective new method for drought risk assessment and, then, provides theoretical support for the government and production departments to master drought information and formulate disaster prevention and mitigation measures.

The model in this paper not only solves the problem that the result and the rule of individual subjective judgment are always inconsistent owing to not fully considering the randomness of the possibility function, but also solves the problem that it’s difficult to ascertain the attribution of decision objects, when several components of grey clustering coefficient vector tend to be balanced. It provides a new idea for the development of the grey clustering model. The rationality and validity of the model are illustrated by taking 18 cities in Henan Province as examples.

The purpose of this study is to investigate the influence mechanisms of multi-level ecological participants on technological innovation capabilities within the focal small and mid-size enterprises' (SME) innovation ecosystem. The author examines the moderating role of the innovation ecological environment.

With the lenses of innovation ecosystem theory, technological innovation theory and ecological theory, the author constructs and empirically tests a conceptual framework for exploring the effects of the focal SME's connections with universities and research institutions, and the industrial chain and ecosphere on their independent and collaborative innovation capabilities. The innovation ecological environment is employed as a moderating variable in the proposed model. The author issued email questionnaires to managers at innovative SMEs in Shenzhen, Shanghai and Jiangsu provinces. The data were used for multiple regression analyses to test the hypotheses.

As predicted, the author found that SMEs’ cooperation with universities and research institutions positively affects independent and collaborative innovation capability. The relationships between the industrial chain, the ecosphere and independent and collaborative innovation capabilities are all inverted U-shaped. Additionally, the author demonstrates that the innovation ecological environment positively moderates relationships between the focal SME's ecological participants and these two types of technological innovation capabilities.

The results enrich research on innovation ecosystems and technological innovation capability and provide important managerial implications for Chinese SMEs to enhance their technological innovation capability by constructing and coordinating innovation ecosystems. It also allows China, as well as other developing countries, to cultivate world-class enterprises as an innovative nation.

The aim is to apply pseudo‐random correlation method to detect very weak electrical signals because of various natural and artificial electron‐magnetic interferences in electrical prospecting.

Electrical prospecting is an important method of geophysical exploration and the electrical prospecting instruments are required to detect very weak electrical signals against strong interferences. Recently, pseudo‐random correlation coding has been widely applied in telecommunications and measurement and test systems to improve the signal noise ratio with great success, but has not been used in electric prospecting. This paper theoretically investigated the application model of pseudo‐random correlation techniques in electrical prospecting.

The model of pseudo‐random correlation techniques in electrical prospecting, including its principle, detailed protocol and parameter selection, is established.

With the continuing improvement in the capacity of electrical prospecting transmitters, the pseudo‐random correlation method will be widely used in electrical prospecting.

The pseudo‐random correlation techniques is originally investigated for its application in electrical prospecting. This paper is aimed at researchers and engineers in geophysical exploration.

China’s accelerated urbanisation leads directly to pressure on the urban environment. The purpose of this paper is to identify best practices involved in a real sustainable community projects for the experience to be replicated in future.

To explore the practical development experiences and technological applications, a case study was conducted, involving both document analysis and semi-structured interviews.

The findings identify the green technologies and strategies used in the project planning and design process. The social considerations of the project development are also recognised in providing comfort, convenience and safety for their residents. Furthermore, the research highlights the fact that sustainable communities can incur less operational costs compared with traditional ones and therefore provide a feasible option for clients with a greater capability for upfront investment.

The results of the research provide valuable references for developers in the development of sustainable communities in both China and other countries.

Knowledge sharing (KS) of employees has numerous benefits for organizations. Therefore, the aim of this study is to provide a model for KS in research centers (RCs) that can facilitate the employee's knowledge sharing behavior (KSB).

Based on the extensive literature review, a valid instrument was adopted to collect the required data set on KS, KSB and intention to KS, and finally 317 complete questionnaires were collected from Iranian research centers. The structural equation modeling (SEM) was used to assess the measurement model and to test the research hypotheses.

The findings show that intrinsic and extrinsic motivational factors and intention to methods of KS play an important role in KSB. In other words, simultaneous supply of motivational factors and KS methods interesting for employees lead to their KSB. The SEM confirmed the research model and showed a good fit of it.

The implication emanating from this study is that the employees' KSB in RCs as a significant part depends on simultaneous supplying of motivational factors (especially intrinsic motivational factors) and methods of KS that are interesting for employees.

What distinguishes this study from other studies in KS domain could be implied in two subjects. First, the presented model is simple and prepared of the introduced factors, which will lead to KSB. Second, this study was conducted in diverse research fields such as electrical and electronics, telecommunications, materials, chemistry, biotechnology, information technology, management and industrial engineering, computer network security, mechanical and manufacturing. The research model was derived from the collected data of these areas that is unique in this domain.

The purpose of this paper is to investigate the microstructures, slag inclusions, morphology and composition of ancient Chinese iron coins exhumed from Emei Mountain and Baoji after 818‐966 years of being imbedded underground.

Metallography, scanning electron microscopy, energy dispersive spectrometry, X‐ray photoelectron spectrometry and Fourier transform infrared spectroscopy were employed.

The results showed that archaeological coins exhibited characteristics of a typical hypoeutectic white cast iron, with slag inclusions of FeS strips and phosphate. Porous or hexagonal platey corrosion products were discovered on the archaeological iron coin, which were mainly identified as Fe₂O₃, FeOOH, Fe_x(OH)_1−xCO₃ and Fe_x(OH)_1−xSO₄. The possible corrosion mechanisms for the iron coins were discussed based on the corrosion products.

This study revealed the characterization of corrosion products on archaeological iron coins and may provide guidance for the preservation of archaeological iron.