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The purpose of this paper is to clarify how the micro-structure and -properties of wool fibers influence the pilling property of woolen fabrics.

The fuzzing and pilling property of woolen fabrics was investigated, based on micro-scale including basic structural characteristics of wool fibers, wool scale topography and surface friction, etc. Scanning electron microscope was used to analyze wool fiber structure; frictional coefficients were measured by capstan method. Then three different kinds of wool fibers are spun into yarns, then knitted into woolen fabrics, whose pilling grade were estimated by means of Pillbox method.

Results show that the finer the fiber, the fabric pilling degree will be higher; the shorter the fiber, the fabric’s pilling is more serious; the number of pilling is decreasing with the increasing number of crimp; the longer the scales, the better anti-pilling property of fabrics, while the larger the scale thickness, the worse the anti-pilling property; and initially, with the increasing DFEs, fabrics are not easy to pilling, however, there exists a critical value.

Fuzzing and pilling property of woolen fabrics are affected by number of factors, including raw fibers, yarns, fabric tissue and finishing process, etc. In this paper, the authors exclude the influence of yarns’ parameter and fabrics’ tissue, etc., but focus on the micro-structure and -properties of raw wool fibers; and establish a direct connection between fabrics’ pilling property and fibers’ parameters.

This paper aims to report on a new pilling measurement system that has been developed using image processing technique.

A pilling assessment cabinet is designed and developed which captures images and a software is developed to process and analyze the image of a pilled fabric to find out the various pilling parameters such as total number of pills, total area of the pills, mean area and number of pills per unit area. The image processing software processed image data of both the existing subjective assessment standards and pilled fabrics and assign suitable grades for comparison.

The grades assigned by the machine correlates well with that of the experts grades and the results are reliably reproducible. The system can count the number of pills, find their total area, and their mean area. The results of EMPA‐W2 and EMPA‐W3 standards behave almost similar. The ASTM standards also gives somewhat the same results as the EMPA standards in number of pills but has a wide variation in the pilled area and mean pill area. The IWS standards produced an entirely different result from the other two standards, which leads us to the conclusion that all these standards are not objectively comparable to each other.

The machine grade becomes a suitable methodology to compare the different grading systems.

Traditional pilling tests are subjective by nature. Moreover, standards set by different organizations are not comparable with each other. This method presents a more universal and objective approach to describe the nature of the pilling.

The purpose of this paper is to develop a new objective evaluation method of fabric pilling using data-driven visual attention model.

First, the multi-scale filtering images are formed by Gaussian pyramid decomposition. Second, center-surround differences algorithm is used between multi-scale filtering images to build saliency map. On this basis, the pilling information is segmented from saliency map by the segmentation threshold. Finally, the pilling is objectively evaluated by extracting pilling feature. Experimental result shows that compared with the traditional detection methods, the proposed objective evaluation method has strong anti-interference ability, and correct classification rate (CCR) is 96 percent.

Fabric pilling saliency can be effectively improved by data-driven visual attention model, which will lead to stronger anti-interference ability and higher correct classification rate.

To void uneven illumination, noise, and texture interference, the proposed method can enhance the saliency of small targets in saliency map using a bottom-up visual attention model. Through the threshold segmentation according to pilling feature, the pilling information is effectively from the fabric texture. Pilling feature about pilling area density is extracted to pilling grade evaluation.

Pilling and abrasion resistance are two of the most important mechanical properties of the fabric that influence the appearance and performance of the fabric, particularly in the case of knitted fabrics. Since, these fabric features are affected by fabric structure the aim of present research is to investigate how utilizing miss stitches and tuck stitches in the fabric structure for design purposes will influence the pilling and abrasion resistance of interlock weft-knitted fabrics.

In this research, interlock fabrics with different number of miss or tuck stitches on successive Wales were produced and pilling performance and abrasion resistance of the fabrics were investigated.

The results revealed that increasing the number of miss/tuck stitches on successive Wales decreases the abrasion resistance and enhances the pilling tendency of the fabric. The presence of miss/tuck stitches on both sides of the fabric improves the abrasion resistance and pilling performance of the fabric compared to fabrics containing these stitches on one side of the fabric. Furthermore, the fabric resistance against abrasion and pilling is higher in fabrics consisting of miss stitches compared to fabrics consisting of tuck stitches.

The use of tuck and miss stitches in designing the weft-knitted fabrics is a common method for producing fabrics with variety of knit patterns. Since pilling and abrasion resistance of the fabric influence on its appearance and performance, and none of the previous research studied the pilling and abrasion resistance of interlock-knitted fabrics from the point of presence of tuck and miss stitches on successive Wales of the fabric, this subject has been surveyed in the present research.

This paper examines the relationship between poison pills, real earnings management and initial public offering (IPO) failure.

The authors sampled 2,997 IPO firms that went public during 1993-2015.

The authors find that IPO firms manipulate earnings upward using real earnings management. The authors also find that IPO firms exhibiting a higher level of real earnings management have a higher probability of IPO failure. In addition, the authors find that weak shareholders' governance is positively associated with IPO failure.

These results suggest that poor governance structures in failed firms open the door to manipulating real activities and increasing operational risk.

The study findings are of most significant interest to potential investors and other stakeholders affiliated with a firm going public, an auditor, an underwriter, the lawyers who consult with the firm and employees or executives who might consider joining that firm.

Pilling is a fabric surface fault comprising of small, fuzzy balls on the surface of a fabric that leads to poor handle and quality. The purpose of this paper is to investigate the effect of the fabric color in terms of depth and hue on the visual perception of pilling on the fabric surface.

Acrylic fabrics were prepared at various color depths and hues and then were applied with relatively equal amount of pilling on the surface of samples. The amount of perceived pilling was evaluated by human observers by employing paired comparison method and the results were analyzed using statistical methods.

According to the results, color depth and the visual perception of pilling in achromatic sample were nearly independent. Color hue can be considered as an important factor in the visual perception of pilling so when the color contrast between the pill and background decreases, the visual perception of pilling decreases as well. Hence, the achromatic sample have the most amount of pilling perception whereas green and blue samples show less pilling, in visual sensation.

There is a strong demand for acrylic fabrics in apparel industry but they have high tendency for pilling formation. To overcome this problem, experts have suggested some methods to prevent or reduce pilling. If it is proved that color influences on pilling perception, an useful instruction will be available for acrylic fabric manufacturers in order to satisfy their customer with good quality of products. In this work, the authors tried to find such relationships between the color and the pilling perception for human observers.

Poison pill securities can be used to deter takeover activity by making the acquisition cost prohibitive or to increase bargaining power of target firms. Poison pills, which are also known as shareholder rights plans, are typically used in conjunction with other takeover defense mechanisms, such as anti‐takeover charter amendments or dual classes of stock. This study examines the role that debt plays as an anti‐takeover strategy in the presence of poison pills. The results show that, on average, capital markets have little reaction to poison pill announcements. A regression equation, however, shows that announcement period abnormal returns are positively related to leverage ratios. This paper provides empirical evidence that the capital structure of firms plays an important role in the perceived strength of poison pills.

This paper aims to provide an initial determination of the date of construction, locations and a typology of design of the pill‐boxes of the Gin Drinker's Line constructed by the colonial Hong Kong Government.

Post‐war aerial photos taken by the Royal Air Force and R.C. Huntings were examined and site visits made to locate and measure the pill‐boxes. Relevant archive materials were consulted to help interpret findings.

A total of 76 pill‐boxes, most in ruins due to post‐war destruction for obtaining their steel bars, were mapped on a 1:25,000 scale to give a good idea of the nature of the Gin Drinker's Line. The study finds that, of these, 50 have survived. The pill‐boxes predated those built in the UK to anticipate of German landing.

The paper demonstrates how aerial photos can be used for historical research and conservation planning. Though the locations of the pill‐boxes identified are subject to detailed site surveying, the basic pattern of pill‐box distribution has been identified.

This is the first attempt to map the Gin Drinker's Line and classify its pill‐boxes. The findings are useful references for the actual conservation of colonial heritage in Hong Kong as part of China, as well as for further inquiry into the military history of the Second World War.

The purpose of this paper is to examine the effect of stock price crash risk on the adoption of poison pills.

The authors estimate logit and probit regressions. Their sample includes 185 Brazilian public firms for the period 2010–2018. Following previous studies, the authors use the negative skewness of firm-specific weekly returns and the down-to-up volatility of firm-specific weekly returns as measures of firm's stock price crash risk. As proxies of poison pills, the authors employ the “conventional” poison pills in their baseline models and the “eternity” poison pills, which prevent the removal of poison pills from bylaws, in additional models.

The authors find that stock price crash risk measures are not associated with poison pill adoption. However, although stock price crash risk does not lead to poison pill adoption as a complementary corporate governance mechanism that protects firms against hostile takeover attempts, further results show that managers do not draw on stock price crash risk as a pretext to entrench themselves. Additional analyses also highlight that CEO power seems to play a role in moderating the relationship between stock price crash risk and eternity poison pill adoption.

The authors contribute to the literature on stock price crash risk, which calls for research in international contexts to better understand the effect of stock price crash risk on country-specific idiosyncratic features. The authors discuss a controversial anti-takeover mechanism that has been debated by Brazilian policymakers.

The paper aims to build a finite element simulation model for pilling of polyester hairiness on the fabric to study the effects of hairiness performance on pilling and reveal pilling mechanisms.

The finite element simulation model of pilling of polyester hairiness was established by ABAQUS. Polyester hairiness was treated as elastic thin rod, which was divided by two-node linear three-dimensional truss element. The effects of hairiness elastic modulus, hairiness friction coefficient and hairiness diameter on frictional dissipation energy, strain energy and kinetic energy produced by pilling have been studied. The analysis solution values were compared with the finite element simulation results, which was used to verify finite element simulation.

The paper provides new insights about how to reveal pilling mechanisms of polyester hairiness with different performance. Comparing finite element simulation results with analysis solutions shows that the fitness is greater than 0.96, which verifies finite element simulation. Larger hairiness elastic modulus gives rise to higher friction dissipation energy and strain energy of hairiness but lower kinetic energy. Increasing friction coefficient enhances friction dissipation and strain energy of hairiness. However, kinetic energy decreases with the increase of friction coefficient. Hairiness diameter also has an important effect on hairiness entanglement and pilling. Increasing hairiness diameter can decrease friction dissipation energy but enhance strain energy and kinetic energy.

Finite element simulation was verified by analysis solutions. The solutions include friction dissipation energy, strain energy and kinetic energy, which cannot measured b experiment. Therefore, researchers are encouraged to simulate pilling to obtain pilling grades, which be compared with experiment results.

Pilling of polyester hairiness was simulated by ABAQUS. This method makes pilling process visualization, and pilling mechanisms was revealed from non-linear dynamics.