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The paper aims to study cut resistant property of basic weft plain-knitted fabric for protective clothing.

Effects of fiber materials, fabric direction and knitting technology (sinking-depth) were explored, respectively. Cut process of fabric was tracked and the theoretical analysis was provided to evaluate energy transferring of cutting. Fiber-based cut behavior was observed by SEM images. Deformation energy stored in the loop due to yarn bending was regard as initial elastic potential energy of the fabric, which was related to loop structure.

Cut resistance of the fiber material was the dominant factor for cut resistance of weft plain-knitted fabric, while unit loop structure played a critical role in improving cut resistance.

Cut resistance of the fiber material was the dominant factor for cut resistance of weft plain-knitted fabric, while the unit loop structure played a critical role in improving cut resistance.

The paper provides theoretical support of developing flexible protective clothing.

The purpose of this paper is to investigate the various factors that influence consumer trust and privacy on e-commerce system and identify different ethical factors that affect consumer perceptions toward e-commerce adoption.

The theoretical background used in this study was critical theory on trust in e-commerce. Online survey from Second Life users was conducted to study ethical issues in e-commerce and their influencing factors.

The results were focussed on significance of e-commerce ethics on consumer purchase and its influence on online marketing. The ethical performance of the e-commerce web site will facilitate an increase in trust, which in turn enhances customer commitment and loyalty.

The survey data in this study has some common method bias. The possibility of the existence of the common method bias cannot be completely eliminated. Security and privacy are the two major aspects that drive online businesses which lead online consumers to develop trust on the digital environment.

The findings on e-commerce ethical research will be useful for current management practice such as making business policies and strategies and sharing information to managers and organization leaders.

With the introduction of internet and e-commerce a large of companies has been performing their business transactions through electronic network. Increasing communication technologies has bought speedy changes in online business transactions. E-commerce networks are playing a pivotal role in online business and consumers are more concerned on ethical issues of e-commerce including security, privacy and trust.

The purpose of this paper is: to track the methods by which farmers access groundwater for irrigation in the North China Plain (NCP); to explore whether climate factors influence farmers’ decisions on the methods of groundwater access for irrigation; and to examine whether the amount of groundwater use for irrigation and crop yield systematically differ across groups of farmers using various methods of groundwater access, and how climate factors affect them.

Descriptive statistical analysis and econometric models are used on household survey data collected over several years and county-level climate data.

Over the past few decades, a significant share of farmers have switched the methods of groundwater access from collective tubewells to own tubewells or groundwater markets. Farmers who bought water from groundwater markets applied less water to wheat plots than those who had their own tubewells. However, wheat yield was not negatively affected. Both average climate conditions and long-term variations were found to be related to farmers’ choice of methods of groundwater access for irrigation. More frequent droughts and increasingly volatile temperatures both increased the likelihood of farmers gaining groundwater irrigation from markets.

The analysis results suggest farmers are using groundwater markets to help them adapt to climate change. Applying empirical analysis to identify the impact of the methods by which farmers access groundwater for irrigation on the amount of groundwater use and crop yield will help policy makers design reasonable adaptation policies for the NCP.

In the grid‐based simulation, the resource application needed is distributed in the grid environment as grid service, and time management is a key problem in the simulation system. Grid workflow provides convenience for grid user to management and executes grid services. But it emphasizes process and no time‐management, so a temporally constrained grid workflow model is pointed out based on grid flow with temporally constraint to schedule resources and manage time.

The temporally constrained grid workflow model is distributed model: the federate has local temporal constraints and interactive temporal constraints among federates. The problem to manage time is a temporally distributed constraint satisfaction problem given deadline time and duration time of grid services. Multi‐asynchronous weak‐commitment search (AWS) algorithm is an approach to resolve DCSP, so a practical example of a simulation project‐based grid system was presented to introduce application of Multi‐AWS algorithm.

The temporally constrained grid workflow is based temporal reasoning and grid workflow description about grid services.

The new problem about scheduling resources and managing time in the grid‐based simulation is pointed out; and the approach to resolve the problem is applied into a practical example.

The purpose of this paper is to acquire doubly variable precision‐based knowledge rules from incomplete decision tables (IDTs) in the framework of pansystems methodology. It suggests a new variable precision limited tolerance – a special pansystems relation – rough set model with precision inclusion and a reduct procedure in which it overcomes the non‐monotony in forming tolerance classes when reducing an attribute from attribute set.

Through introducing variable precision and limited tolerance relation in IDT, it constructs symmetric binary relation, dissimilar to non‐symmetric relation proposed by others, and then forms tolerance classes. It proposes a new reduction procedure with absolute value calculation to avoid tolerance classes being non‐monotone. Using variable inclusion, it obtains lower and upper approximations with noises.

Tolerance classes are not monotone with the reduction of attribute from attribute set in the proposed variable precision and limited tolerance relation, but it remains symmetry. Proposed reduction procedure with absolute value calculation is a new approach in adjudging whether a reduct equals to the original whole attribute set within a error range or not.

Using variable precision and limited rough set model with variable inclusion to mine deep knowledge from IDT is a paradise in knowledge discovery in dealing with non‐determinative and vague problems.

The formation of symmetric tolerance relation is natural. The reduction procedure with absolute value calculation is new and not similar to those existed in literatures.

The purpose of this paper is to develop an environmentally friendly dyeing process using brown pigment from chestnut shells (BPFCS). This material is obtained from foodstuff residues and can make a significant contribution to reusing a reproducible biomass resource, economizing petroleum, avoiding water pollution and protecting human health.

The brown pigment is extracted from the raw material and purified with solvents containing 30 and 100 per cent EtOH. It is then used to dye flax fabric in aqueous solution with added NaCl as a dye accelerator. The effects of dyeing conditions and fastness are investigated. The pigment, and the pristine and dyed fabrics are analysed by Fourier‐transform infrared spectroscopy (FT‐IR) and the fabric samples are observed using a scanning electron microscope (SEM). Fastness to washing, rubbing and light are also measured.

BPFCS show promising dyeability on cellulosic fibers. White flax fabric is successfully dyed with the pigment to a yellow‐brown colour. The base dyeing conditions are as follows: pigment concentration 16 g/l, NaCl concentration 10 g/l, liquor ratio 10:1, temperature 95°C, dyeing time 40 min. The dyed fabrics have lower fastness to washing and higher fastness to rubbing and light. A total of 4 per cent Al³⁺ or Fe²⁺ treatment of dyed fabric can improve fastness to washing, but decrease fastness to rubbing. The yellowish‐brown samples are transformed to brown or dark‐green after Al³⁺ or Fe²⁺ treatment, respectively. The pigment is a mixture with abundant hydroxyl groups.

The studies of dyeing conditions and fastness are carried out in detail as BPFCS used as a dye. However, a qualitative analysis of the pigment could not be performed due to the difficulty of separating the mixture. The BPFCS used in this paper can dye cellulosic fiber and can also be used to dye other fibers such as silk, wool and PET. Dyeing conditions for these other fibers need to be investigated.

BPFCS may play an important role in the dyeing industries because of its good dyeability, lack of toxicity and resistance to water, rubbing and light. The present work offers an environmentally friendly dye and a simple dyeing method.

At present, no report exists in the literature of work on dyeing flax fabric with BPFCS. This paper represents a preliminary study to determine the relationships of dyeing conditions to fastness and the role of mordant. BPFCS appears to be a new and practically useful natural dye.

The purpose of this paper is to investigate service quality of e-commerce Websites in online platform and their contribution on e-business promotion.

The online survey was performed on a survey portal provided by Nepal Telecom in Nepal.

The findings of this study suggest that information quality and online service quality were the key determinants for user satisfaction and sustainability of e-commerce technology.

Research opportunities of web services and e-commerce area are fruitful and important for both academics and practitioners.

The findings on online service quality of e-commerce technology will be useful for current management practice such as making business policies and strategies and sharing information to managers and organization leaders. This study can be used for e-commerce Website operators wishing to enhance the competitiveness of their Websites in the highly competitive online market.

E-commerce is considered an excellent alternative for individuals and companies to reach new customers. Service quality delivery through Internet is an essential strategy to success, more important than price and web presence. The e-commerce Website has been identified as having a significant impact on business activities in solving the geographical problem. A number of performance problems have been observed for e-commerce Websites, and much work has gone into characterizing the performance of web-servers and Internet applications.

The purposes of this paper are to study the characterization of drill bit breakage in printed circuit board (PCB) drilling process based on high-speed video analysis and to provide an important reference for micro drill bit breakage prediction.

Based on PCB drilling experiment, the high-speed camera was used to observe the micro drill breakage process and the chip removal process. The variation of chip in the drilling process was studied and one of the key reasons for the drill bit breakage was analysed. Finally, the swing angles’ feature during the breakage process of the micro drill was analysed and researched with the image processing tools of MATLAB.

The micro drill was prone to breakage mainly because of the blocked chips. The breakage process of the micro drill can be divided into the stage of stable chips evacuation, the stage of blocked chips and the stage of drill bit breakage. The radians of swing angles were basically in the range of ±0.01 when the drilling possess is normal. But when the radians of swing angles considerably exceeded the range of ±0.01, the micro drill bit may be fractured.

This paper presented the method to study the characterization of drill bit breakage in the PCB drilling process by using high-speed video analysis technology. Meanwhile, an effective suggestion about monitoring the radians of swing angles to predict the breakage of micro drill bit was also provided.

Micro-holes are drilled and plated in flexible printed circuit boards (FPCs) for connecting circuits from different layers. More holes, with diameters smaller than 0.3 mm, are required to be drilled in smaller areas with flexible circuits’ miniaturization. The micro-hole quality of micro-drilling is one of the biggest issues of the flexible circuit manufacturers’ production. However, it is not easy to control the quality of micro-holes. The purpose of this study was to conduct research on the tool wear characteristics of FPC drilling process and its influence on micro-hole quality to improve the micro-hole quality of FPC.

The tool-wear characteristics of micro-drills after FPC drilling were observed. The influence of spindle speed, feed rate, number of drilled holes and entry board materials on tool-wear was analyzed. The hole qualities of FPC micro-drilling were measured and observed. The relationship between tool-wear and hole quality was analyzed.

The result showed that the tool-wear characteristics of FPC micro-drilling was similar to the tool-wear characteristics of rigid printed circuit board (RPC) micro-drilling. Abrasive wear occurred on both the main cutting edges and the chisel edges of micro-drills, even though there was no glass fiber reinforcing the cloth inside FPC. Resin adhesion was observed on the chisel edge. The influence of feed and number of drilled holes on tool-wear was significant. Tool-wear significantly influences the hole quality of FPC. Tool-wear will largely decrease the hole position accuracy of FPC micro-holes. Tool-wear will increase the thickness of PI nail heads and the height of exit burrs. Fracture was the main difference between tool wear of FPC and RPC micro-drilling. Resin adhesion of RPC was much more severe than FPC micro-drilling. Increasing the spindle speed properly may improve tool life and hole quality.

The technology and manufacturing of FPC has been little investigated. Research on micro-drilling FPC and research data is lacking so far. The micro-hole quality directly affects the reliability of FPC. Thus, improving the micro-hole quality of FPC is very important.

The flexible printed circuit (FPC) board with the characteristic of light and thin strengthened confronted the growing miniaturization requirements of the electronic product and the popularity of wearable devices. The reliability of circuit could be influenced by the hole quality of FPC, such as burrs, which is one of the major problem in FPC.

In this paper, micro-drill with a diameter of 0.1 mm was used to drill the double-sided flexible copper clad laminate. The thrust force, the burr and tool wear were investigated. The influencing factors of the height of the burrs were studied. The relationship between the thrust force and the height of the burrs was also explored. Finally, the formation mechanism of burrs was analyzed.

The entrance burrs were usually less than the exit burrs. The burr height increased with the feed per rotation. The height of the burr increased with the increase of the thrust force for the plastic deformation of the copper foil was dominant. The abrasion of the drill gave rise to increase the height of burr. In micro-hole drilling, the growth of burrs can be suppressed effectively by reducing the clearance between the FPC and the backup plate. The thrust force would be controlled in a certain range to reduce the burr with specific drilling parameters. There existed a certain relationship of Gaussian distribution between the height of the burrs and the thrust force of FPC.

The reliability of the integrated circuit was directly affected by the burrs of the FPC. This research on the formation mechanism of FPC burrs and forecast of burr height provided a firm foundation for further work in the area of improvement of the micro-hole quality.