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This paper aims to provide a process-driven scientific data quality (DQ) monitoring framework by information product map (IP-Map) in identifying the root causes of poor DQ issues so as to assure the quality of scientific data.

First, a general scientific data life cycle model is constructed based on eight classical models and 37 researchers’ experience. Then, the IP-Map is constructed to visualize the scientific data manufacturing process. After that, the potential deficiencies that may arise and DQ issues are examined from the aspects of process and data stakeholders. Finally, the corresponding strategies for improving scientific DQ are put forward.

The scientific data manufacturing process and data stakeholders’ responsibilities could be clearly visualized by the IP-Map. The proposed process-driven framework is helpful in clarifying the root causes of DQ vulnerabilities in scientific data.

As for the implications for researchers, the process-driven framework proposed in this paper provides a better understanding of scientific DQ issues during implementing a research project as well as providing a useful method to analyse those DQ issues based on IP-Map approach from the aspects of process and data stakeholders.

The process-driven framework is beneficial for the research institutions, scientific data management centres and researchers to better manage the scientific data manufacturing process and solve the scientific DQ issues.

This research proposes a general scientific data life cycle model and further provides a process-driven scientific DQ monitoring framework for identifying the root causes of poor data issues from the aspects of process and stakeholders which have been ignored by existing information technology-driven solutions. This study is likely to lead to an improved approach to assuring the scientific DQ and is applicable in different research fields.

This study aims to address the problem of low-temperature wave soldering in industry production with Sn-9Zn-2.5 Bi-1.5In alloys and develop qualified process parameters. Sn–Zn eutectic alloys are lead-free solders applied in consumer electronics due to their low melting point, high strength, and low cost. In the electronic assembly industry, Sn–Zn eutectic alloys have great potential for use.

This paper explored developing and implementing process parameters for low-temperature wave soldering of Sn–Zn alloys (SN-9ZN-2.5BI-1.5 In). A two-factor, three-level design of the experiments experiment was designed to simulate various conditions parameters encountered in Sn–Zn soldering, developed the nitrogen protection device of waving soldering and proposed the optimal process parameters to realize mass production of low-temperature wave soldering on Sn–Zn alloys.

The Sn-9Zn-2.5 Bi-1.5In alloy can overcome the Zn oxidation problem, achieve low-temperature wave soldering and meet IPC standards, but requires the development of nitrogen protection devices and the optimization of a series of process parameters. The design experiment reveals that preheating temperature, soldering temperature and flux affect failure phenomena. Finally, combined with the process test results, an effective method to support mass production.

In term of overcome Zn’s oxidation characteristics, anti-oxidation wave welding device needs to be studied. Various process parameters need to be developed to achieve a welding process with lower temperature than that of lead solder(Sn–Pb) and lead-free SAC(Sn-0.3Ag-0.7Cu). The process window of Sn–Zn series alloy (Sn-9Zn-2.5 Bi-1.5In alloy) is narrow. A more stringent quality control chart is required to make mass production.

In this research, the soldering temperature of Sn-9Zn-2.5 Bi-1.5In is 5 °C and 25 °C lower than Sn–Pb and Sn-0.3Ag-0.7Cu(SAC0307). To the best of the authors’ knowledge, this work was the first time to apply Sn–Zn solder alloy under actual production conditions on wave soldering, which was of great significance for the study of wave soldering of the same kind of solder alloy.

Low-temperature wave soldering can supported green manufacturing widely, offering a new path to achieve carbon emissions for many factories and also combat to international climate change.

There are many research papers on Sn–Zn alloys, but methods of achieving low-temperature wave soldering to meet IPC standards are infrequent. Especially the process control method that can be mass-produced is more challenging. In addition, the metal storage is very high and the cost is relatively low, which is of great help to provide enterprise competitiveness and can also support the development of green manufacturing, which has a good role in promoting the broader development of the Sn–Zn series.

This paper aims to present the slip/no-slip design in two-dimensional water-lubricated tilting pad thrust bearings (TPTBs) considering the turbulence effect and shifting of pressure centers.

A numerical model is established to analyze the slip condition and the effect of turbulence according to a Reynolds number defined in terms of the slip condition. Simulations are carried out for eccentrically and centrally pivoted bearings and the influence of different slip parameters is discussed.

A considerable enhancement in load capacity, as well as a reduction in friction, can be achieved by heterogeneous slip/no-slip surface designs for lubricated sliding contacts, especially for near parallel pad configurations. The optimized design largely depends on the pivot position. The load capacity increases by 174 per cent for eccentrically pivoted bearings and 159 per cent for centrally pivoted bearings for a suitable design. When slip zone locates at the middle of the radial direction or close to the inner edge, the performance of the TPTB is better.

The simplification of slip effect on the turbulence (definition of Reynolds number) can only describe the trend of the increasing turbulence due to slip condition. The accurate turbulence expression considering the boundary slip needs further explorations.

The shifting of pressure center due to the slip/no-slip design for TPTBs is investigated in this study. The turbulence effect and influence of slip parameters is discussed for large water-lubricated bearings.

In the electronic assembly industry, low-temperature soldering holds great potential to be used in surface mounting technology. Tin–bismuth (Sn–Bi) eutectic alloys are lead-free solders applied in consumer electronics because of their low melting point, high strength and low cost. This paper aims to investigate how to address the problem of hot tear crack formation during Sn–Bi low-temperature solder (LTS) in the mass production of consumer electronics.

This paper explored the development of hot tear cracks during Sn–Bi soldering in the fabrication of flip chip ball grid arrays. Experiments were designed to simulate various conditions encountered in Sn–Bi soldering. Quantitative analysis was conducted on the number of hot tear cracks observed in different alloy compositions and solder volumes to explore the primary cause of hot tear cracks and possible methods to suppress crack formation.

Hot tear cracks existed in Sn–Bi solders with different bismuth (Bi) contents, but increasing the solder volume reduced the number of hot tear cracks. Experiments were designed to test the degree of chip transient thermal warpage with temperature change, and, according to the results, glue was dispensed in specific areas to reduce chip warpage deformation. Finally, the results of combined process experiments pointed to an effective method of low-temperature soldering to suppress hot tear cracks.

The study focuses on Sn–Bi solders only without other solder pastes such as SAC305 or Sn–Zn series.

With the growing popularity of smart electronics, especially in intelligent terminals, new energy vehicles electronics, solar photovoltaic and other field, there will be more and more demand for low- temperature, energy-saving, lead-free solders. Therefore, this study will help the industry to roll out LTS (Sn–Bi) solutions rapidly.

In the long term, lean and green manufacturing is expected to be essential for maintaining an advanced manufacturing industry across the world. Developing new LTSs and soldering processes is the most effective, direct solution for energy conservation and emission mitigation. With the growing popularity of smart electronics, especially in intelligent terminals, new energy vehicles and solar photovoltaics, there would be an increased demand for low-temperature, energy-saving, lead-free techniques.

Although there are many methods that can be used to suppress hot tear cracks, there is little research on how to control the hot tear cracks caused by the low-temperature soldering of Sn–Bi in laptop applications. The authors studied the hot tear cracks that developed during the world’s first mass production of 50 million personal laptops based on low-temperature Sn–Bi alloy solder pastes. By controlling the Bi content, redesigning the solder paste printing process (e.g. through a printer’s stencil) and adding dispensing processes, the authors obtained reliable and stable experimental data and conclusions.

To develop an automated system for identifying and repairing cracks in asphalt pavements, addressing the urgent need for efficient pavement maintenance solutions amidst increasing workloads and decreasing budgets.

The research was conducted in two main stages: Crack identification: Utilizing the U-Net deep learning model for pixel-level segmentation to identify pavement cracks, followed by morphological operations such as thinning and spur removal to refine the crack trajectories. Automated crack repair path planning: Developing an enhanced hybrid ant colony greedy algorithm (EAC-GA), which integrates the ant colony (AC) algorithm, greedy algorithm (GA) and three local enhancement strategies – PointsExchange, Cracks2OPT and Nearby Cracks 2OPT – to plan the most efficient repair paths with minimal redundant distance.

The EAC-GA demonstrated significant advantages in solution quality compared to the GA, the traditional AC and the AC-GA. Experimental validation on repair areas with varying numbers of cracks (16, 26 and 36) confirmed the effectiveness and scalability of the proposed method.

The originality of this research lies in the application of advanced deep learning and optimization algorithms to the specific problem of pavement crack repair. The value is twofold: Technological innovation in the field of pavement maintenance, offering a more efficient and automated approach to a common and costly issue. The potential for significant economic and operational benefits, particularly in the context of reduced maintenance budgets and increasing maintenance demands.

Face contact has a strong impact on the service life of non-contacting gas face seals; the current research which mainly focuses on the face contact had appeared during the startup or shutdown operation. This paper aims to present a closed-form contact model of a gas face seal during the opened operation.

Referring to the axial rub-impact model of rotor dynamics, a closed-form contact model is developed under a nonparallel plane contact condition that corresponds to the local face contact of sealing rings arising from some disturbances during the opened operation. The closed-form contact model and a direct numerical contact model are performed on Gaussian surfaces to compare the contact behavior.

The closed-form contact model is in a good agreement with the direct numerical contact model. However, the closed-form contact model cannot involve the influence of grooves on the sealing ends. The error is eliminated in some other types of gas face seals such as coned gas face seals. Besides non-contacting face seals, the closed-form model can be applied to the axial rub impact of rotor dynamics.

A closed-form contact model of a gas face seal is established during the opened operation. The closed-form contact model is validated by a direct numerical contact model. The closed-form contact model also suits for axial rub-impact of rotor dynamics.

This study aims to focus on the surface curvature, jet to target spacing and jet Reynolds number effects on the heat transfer and fluid flow characteristics of a slot jet impinging on a confined concave target surface at constant jet to target spacing.

Numerical simulations are used in this research. Jet to target spacing, H/B is varying from 1.0 to 2.2, B is the slot width. The jet Reynolds number, Rej, varies from 8,000 to 40,000, and the surface curvature, R2/B, varies from 4 to 20. Results of the target surface heat transfer, flow parameters and fluid flow in the concave channel are performed.

It is found that an obvious backflow occurs near the upper wall. Both the local and averaged Nusselt numbers considered in the defined region respond positively to the Rej. The surface curvature plays a positive role in increasing the averaged Nusselt number for smaller surface curvature (4-15) but affects little as the surface curvature is large enough (> 15). The thermal performance is larger for smaller surface curvature and changes little as the surface curvature is larger than 15. The jet to target spacing shows a negative effect in heat transfer enhancement and thermal performance.

The surface curvature effects are conducted by verifying the concave surface with constant jet size. The flow characteristics are first obtained for the confined impingement cases. Then confined and unconfined slot jet impingements are compared. An ineffective point for surface curvature effects on heat transfer and thermal performance is obtained.

The purpose of this paper is to investigate the economic significance of informal borrowing between friends and relatives in rural China. Guided by an economic model of household‐production interactions, the paper provides results from a survey of over 1,500 households including general linear model and logistic regression results. The paper finds evidence of a “small farm bias” in the use of informal credit, but the paper cannot generalize this to credit rationing as a matter of course. In part, it is believed that a preference for informal borrowing is related to some forms of credit rationing, spillover effects and collateral as some literature suggests, but the results suggest that by no means are these mutually exclusive or exhaustive.

This paper uses regression techniques based on 1,557 farm household surveys gathered by the authors in Shaanxi, Gansu and Henan Provinces in 2007 and 2008.

The paper argues that informal lending amongst friends and relatives cannot be dismissed as a significant economic factor in the financing of China's agricultural sector. A small farm bias in formal lending is indicated by the results, but there are many factors other than credit rationing which affect a households' decision to borrow informally.

The research is limited to the survey data used. China's agricultural economy is too large to assert that the informal‐formal relationships described herein are general, even though the results are supported by other research.

The paper makes the case that the study of agricultural finance in China should include informal lending as part of any credit study. In addition, the paper argues that the use of the term “informal lending” should not generally group familial lending with other forms of interest‐bearing loans such as pawn shops or money lenders.

China's rural credit needs are huge and many farmers do not have access to formal credit. This paper argues that the strength of trust relationships between friends and family is sufficiently high that nearly 60 percent of all credit outstanding is between friends and relatives at zero interest rates.

This, it is believed, is one of the first comprehensive studies on informal lending in China.

The purpose of this paper is to provide an overview of the farm and rural credit system in China. To do this the authors use the so‐called “7 Cs” of credit (these include: Credit, Character, Capacity, Capital, Condition, Capability, and Collateral) and for each “C” provide some aspect of importance related to agricultural finance.

This paper is largely based on a survey of 897 farm households in Shaanxi and Gansu provinces, and extensive interviews of agricultural lenders conducted in the summer and fall of 2009. These data are used in simple form and in regression form to explain a variety of credit issues in China.

A number of key factors related to credit delivery and demand are found. First, using the 7 Cs as a guide proved to be very fruitful for disentangling the many institutional and cultural facets affecting rural credit in China. Under “Character” the authors discuss the cultural characteristics of the Chinese farmer in terms of informal lending and borrowing; under “Capacity” the authors discuss the challenges of delivering credit to farms with limited resources; under “Condition” the authors discuss group guarantees and credit worthy villages, credit rationing and insurance and incomplete markets; under “Capability” the authors discuss income inequality and challenges in economies of scale and size; and for “Collateral” the authors discuss the implications of lack of collateral and limitations on farm economic growth due to the collectivization of land and the potential for agricultural lending from the transferability and mortgagability of land or forestry use rights.

Although the assessment provides a great deal of breadth and depth across many credit‐related issues in China, it is not an exhaustive study. Agricultural and rural credit in China is very complex and in many instance under developed. The survey results from Shaanxi and Gansu tell a story that is consistently told throughout China, but the authors would caution against using the data to characterize farm credit across China as a whole.

Large swaths of China have either no or very rudimentary credit services. Even in areas where credit is in supply there are issues of poverty that could be aided with credit access and delivery. In order to improve livelihoods through credit institutions, it is important to understand rural credit in many dimensions. This paper takes a step in that direction.

Despite the importance of rural credit in China, it is largely understudied and not well understood. This paper makes progress in providing such an understanding. Our reasoning for using our unique approach is that by understanding the 7 Cs of credit one comes to understand the elemental characteristics of the credit decision from the lender's point of view but in a way that takes into account conditions at the farm level. The 7 Cs provide an objective approach to credit assessment that balances both the supply of and demand for credit.

The purpose of this paper is to investigate the relationships between business risks and credit choices of 400 farm households surveyed in Shaanxi province in October 2007 in the Yangling district. More specifically, this paper investigates whether or not rural farm households in China balance business risks from agricultural production with financial risk from the use of debt.

The data were collected through a survey of 400 farm households in Shaanxi province conducted in October 2007. Four separate regressions are run using a credit measure as the dependent variable and measures of profitability, risk, risk aversion, and demography, and debt source (formal versus informal lending) as independent variables.

The model shows evidence of risk balancing. That is, there is strong evidence that Chinese farmers reduce credit use and financial risk, as business risks increase.

The results suggest that Chinese policy makers could encourage the use of finacial leverage and prudent debt use by offering risk reducing programs such as crop insurance, weather insurance, or price insurance.

This paper uses a unique survey form to collect production risk data as well as gather information on credit use and sources. Data were collected so that risk measures could easily be computed using a triangular distribution. Furthermore, this is believed to be the first empirical validation of the risk balancing hypothesis.