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The purpose of this paper is to develop a novel MEMS vector hydrophone with the key features of smaller size, better consistency, higher sensitivity and directional reception, and to develop a highly effective and economical obstacle avoidance sonar system. Currently, the typical vector hydrophones are resonant vector hydrophones based on the accelerometer, which greatly increases the volume and constrains the detection sensitivity. Also, because the system is composed of a number of devices, its size is difficult to be reduced.

A novel double T-shape MEMS vector hydrophone is proposed with a fish’s lateral line organs as prototypes. The structure size and layout location of the piezoresistors were determined by simulation analysis, and the double T-shape microstructure was fabricated integrally by MEMS manufacturing technology, after which, the acoustic package of the microstructure was completed and the prototype was produced. Finally, the packaged hydrophone was calibrated in a standing wave field in the first-class national-defense underwater acoustic calibration station of China. Also, the design and test of an obstacle avoidance sonar system based on the vector hydrophone were completed.

The calibration data show that the double T-shape vector hydrophone has a flat frequency response curve, exhibits a sensitivity of −180 dB (1 kHz, 0 dB reference 1 V/uPa) and shows a good directivity pattern in the form of an “8” shape. The test results of the obstacle avoidance sonar system further verify the feasibility of detecting underwater acoustic signals.

The next work is to increase the sensitivity by optimizing the microstructure and to realize orientation by organizing array.

The hydrophone has the advantages of smaller size, lower cost and directional reception. It can be used to develop highly effective and economical obstacle avoidance sonar system, thus solving the problems of water transport efficiency and traffic safety. The hydrophone has broad application prospects and a huge market potential in the civilian fields.

The MEMS technology and innovative bionic microstructure enable the miniaturization and low cost of the hydrophone. The hydrophone is easy to form array and can narrow the array aperture greatly. So, the hydrophone can be widely used in civil sonar systems.

The purpose of this study is to examine the demand for credit and credit rationing conducted by formal, informal and emerging microfinance lenders in the four poor counties of China.

This paper extends the existing studies on credit rationing in rural China by comparing the determinants of credit rationing by three different lenders, the formal lenders rural credit cooperatives (RCCs), the informal lenders and the new microfinance institutions (MFIs).

MFIs are capable of reaching out to the even poorer households if they develop the loan products based on the income and expenditure flows of these households.

The determinants of credit rationing by three types of institutions are estimated separately.

RCCs in China shall change their policy of discrimination against female-headed households. RCCs shall also simplify the loan application procedures and assess the clients based on their repayment capacities rather than the age or assets alone. RCCs could learn from MFIs to use incomes from migrant workers as a criterion to assess the loan applicants.

gender equity for loan access.

This paper extends the existing studies on credit rationing in rural China by comparing the determinants of credit rationing by three different lenders, the formal lenders (RCCs), the informal lenders and the new MFIs.

Compelling chemical, biochemical, clinical and epidemiological evidence supports the view that the antioxidant nutrients exert vital contributions towards the prevention or delayed onset of cancer and cardiovascular disease. The presence of antioxidants in fruit, vegetables, tea and red wine may help to explain why their presence in the diet is associated with reduced incidence of heart disease and cancer.

The purpose of this paper is to optimize experimental parameters and gain further insights into the plating process in the fabrication of high-density interconnections of printed circuit boards (PCBs) by the rotating disc electrode (RDE) model. Via metallization by copper electrodeposition for interconnection of PCBs has become increasingly important. In this metallization technique, copper is directly filled into the vias using special additives. To investigate electrochemical reaction mechanisms of electrodeposition in aqueous solutions, using experiments on an RDE is common practice.

An electrochemical model is presented to describe the kinetics of copper electrodeposition on an RDE, which builds a bridge between the theoretical and experimental study for non-uniform copper electrodeposition in PCB manufacturing. Comsol Multiphysics, a multiphysics simulation platform, is invited to modeling flow field and potential distribution based on a two-dimensional (2D) axisymmetric physical modeling. The flow pattern in the electrolyte is determined by the 2D Navier–Stokes equations. Primary, secondary and tertiary current distributions are performed by the finite element method of multiphysics coupling.

The ion concentration gradient near the cathode and the thickness of the diffusion layer under different rotating velocities are achieved by the finite element method of multiphysics coupling. The calculated concentration and boundary layer thicknesses agree well with those from the theoretical Levich equation. The effect of fluid flow on the current distribution over the electrode surface is also investigated in this model. The results reveal the impact of flow parameters on the current density distribution and thickness of plating layer, which are most concerned in the production of PCBs.

By RDE electrochemical model, we build a bridge between the theoretical and experimental study for control of uniformity of plating layer by concentration boundary layer in PCB manufacturing. By means of a multiphysics coupling platform, we can accurately analyze and forecast the characteristic of the entire electrochemical system. These results reveal theoretical connections of current density distribution and plating thickness, with controlled parameters in the plating process to further help us comprehensively understand the mechanism of copper electrodeposition.

The uniformity of electrodeposition is the key to successful application of pattern plating because the quality of electrodeposited copper layer has a huge impact on the performance of printed circuit boards (PCBs). The multi-physics coupling technology was used to accurately analyze and forecast the characteristics of electrochemical system. Further, an optimized plating bath was used to achieve a uniform electrodeposition.

A multi-physics coupling numerical simulation based on the finite element method was used to optimize electrodeposition conditions in pattern plating process. The influences of geometric and electrochemical factors on uniformity of current distribution and electrodeposited layer thickness were discussed by multi-physics coupling.

The model results showed that the distance between cathode and anode and the insulating shield had a great impact on uniformity of electrodeposition. By numerical simulation, it had been proved that using an auxiliary cathode was an effective and simple way to improve uniformity of electrodeposition due to redistributing of the current. This helped to achieve more uniform surface of the copper patterns by preventing the edge effect and the roughness of the copper layer was reduced to 1 per cent in the secondary current distribution model.

The research is still in progress with the development of high-performance computers.

A multi-physics coupling platform is an excellent tool for quickly and cheaply studying the process behaviors under a variety of operating conditions.

The numerical simulation method has laid the foundation for the design and improvement of the plating bath.

By multi-physics coupling technology, we built a bridge between theoretical and experimental study for control of uniformity of pattern plating in PCB manufacturing. This method can help optimize the design of plating bath and uniformity of pattern plating in PCB manufacturing.

This study aims to discuss the nutritional value and potential nutraceutical properties of Diospyros kaki L. (DKL); to encapsulate recent studies conducted across the world to develop functional foods using different parts of Persimmon fruit to emphasise on the need for further research on Persimmon fruit.

The methodology of the study involved surveying primary and secondary information generated in the respective field of interest. The papers found most suited for the research problem and objective of the study were selected. The perspectives taken by different studies and researchers were synthesised to generate a solution to the research problems and to bridge the research gaps in the field.

As a result of the global rise in the prevalence of metabolic disorders, researchers are aimed at identifying nutrient rich foods and techniques to develop functional foods for the population. Researchers have recognised the role of fresh fruits and vegetables, whole grains and probiotics, are now interested in leveraging these foods by incorporating them in conventional foods, such as breads, jams, pastas and yoghurts as functional ingredients. One such food that has gained the interests of various researchers is DKL. Owing to its rich macro-and micro-nutrient, as well as phytochemical content various studies have been conducted to explore the possibility of using it as a functional ingredient to develop a range of foods.

A limited studies are available that have investigated the effect of the functional foods developed using different parts of Persimmon fruit on different ailments.

This study collected the data/information from recently published research in the field of health and medicinal benefits of Persimmon fruits and its utilisation to develop functional food.

The purpose of this paper is to examine how Si-shu, a traditional form of local, private education grounded in classical instruction, responded to the rapid modernization of education during the late Qing dynasty and early Republic of China and to explain why these schools, once extraordinarily adaptable, finally disappeared.

The authors have examined both primary and secondary sources, including government reports, education yearbooks, professional annals, public archives, and published research to analyze the social, political and institutional changes that reshaped Si-shu in the context of China's late-19th- and early-20th-century educational modernization.

Si-shu went through four stages of institutional change during the last century. First, they faced increased competition from new-style (westernized) schools during the late Qing dynasty. Second, they engaged in a process of intense self-reform, particularly after the Xinhai Revolution of 1911. Third, they were marginalized by the new educational systems of the Republic of China, especially the Renxu School System of 1922 and the Wuchen School System of 1928. Finally, after the foundation of the People's Republic of China in 1949, they were considered remnants of feudal culture and forcibly replaced by modern schools.

This paper brings hitherto unexplored Chinese sources to an English-speaking audience in an effort to shed new light on the history of traditional Chinese education. The fate of Si-shu was part of the larger modernization of Chinese education – a development that had both advantages and disadvantages.