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The purpose of this paper is to establish and implement a direct topological reanalysis algorithm for general successive structural modifications, based on the updating matrix triangular factorization (UMTF) method for non-topological modification proposed by Song et al. [Computers and Structures, 143(2014):60-72].

In this method, topological modifications are viewed as a union of symbolic and numerical change of structural matrices. The numerical part is dealt with UMTF by directly updating the matrix triangular factors. For symbolic change, an integral structure which consists of all potential nodes/elements is introduced to avoid side effects on the efficiency during successive modifications. Necessary pre- and post processing are also developed for memory-economic matrix manipulation.

The new reanalysis algorithm is applicable to successive general structural modifications for arbitrary modification amplitudes and locations. It explicitly updates the factor matrices of the modified structure and thus guarantees the accuracy as full direct analysis while greatly enhancing the efficiency.

Examples including evolutionary structural optimization and sequential construction analysis show the capability and efficiency of the algorithm.

This innovative paper makes direct topological reanalysis be applicable for successive structural modifications in many different areas.

This paper presents a comprehensive pallet-picking approach for forklift robots, comprising a pallet identification and localization algorithm (PILA) to detect and locate the pallet and a vehicle alignment algorithm (VAA) to align the vehicle fork arms with the targeted pallet.

Opposing vision-based methods or point cloud data strategies, we utilize a low-cost RGB-D camera, and thus PILA exploits both RGB and depth data to quickly and precisely recognize and localize the pallet. The developed method guarantees a high identification rate from RGB images and more precise 3D localization information than a depth camera. Additionally, a deep neural network (DNN) method is applied to detect and locate the pallet in the RGB images. Specifically, the point cloud data is correlated with the labeled region of interest (RoI) in the RGB images, and the pallet's front-face plane is extracted from the point cloud. Furthermore, PILA introduces a universal geometrical rule to identify the pallet's center as a “T-shape” without depending on specific pallet types. Finally, VAA is proposed to implement the vehicle approaching and pallet picking operations as a “proof-of-concept” to test PILA’s performance.

Experimentally, the orientation angle and centric location of the two kinds of pallets are investigated without any artificial marking. The results show that the pallet could be located with a three-dimensional localization accuracy of 1 cm and an angle resolution of 0.4 degrees at a distance of 3 m with the vehicle control algorithm.

PILA’s performance is limited by the current depth camera’s range (< = 3 m), and this is expected to be improved by using a better depth measurement device in the future.

The results demonstrate that the pallets can be located with an accuracy of 1cm along the x, y, and z directions and affording an angular resolution of 0.4 degrees at a distance of 3m in 700ms.

Using Porter’s (1980) generic strategy to define strategic positioning of law firms, this paper aims to explain why some law firms have more/less pay inequality than others do and examine the impact of pay inequality on law firms’ partners and the job satisfaction of their associates.

This paper uses data from The American Lawyer. The strategic positioning, compensation and job satisfaction scores of 614 firm-year observations of US law firms are hand-collected over the period from 2007 to 2016.

Non-equity partners at law firms with differentiation strategy (Porter, 1980) are more likely to build rainmaking ability than those at law firms relying on billable hours. As a result, law firms with differentiation strategy have a narrower pay gap between their equity and non-equity partners than those firms relying on billable hours. After controlling for the effects of strategy on pay inequality using two-stage and three-stage least squares models, this paper finds that a wider pay gap deprives associates of job satisfaction.

Considering strategic positioning, this paper validates why some law firms have more/less pay inequality and proves how pay inequality affects job satisfaction.

In this paper, the authors aim to study the optimal strategy of original equipment manufacturers (OEMs) considering both consumer segmentation and upward substitution of remanufactured products in the product life cycle.

In this paper, the authors develop two remanufacturing models: the OEM remanufacturing model and the authorized remanufacturing model. Then, the authors study the impact of both green consumers' scale and the product life cycle expressed as the market growth rate on the OEM's optimal decision-making. Therefore, the authors derive the optimal solutions of the two models by using game theory.

The authors find that in the case of low market growth rate, when there only exist ordinary consumers, if the substitutability of remanufactured products produced by the OEM is below one threshold or above another threshold, the OEM can obtain higher profit in the OEM remanufacturing model, and vice versa. If the substitutability of remanufactured products produced by the OEM is below a threshold when there are both ordinary and green consumers, the OEM prefers the authorized remanufacturing model; and vice versa. Moreover, in the case of high market growth rate, the OEM prefers the OEM remanufacturing model only when the substitution-level in OEM remanufacturing model is above a threshold.

The present study fills the gap in existing researches by simultaneously discussing product life cycle and green consumers' scale. The authors provide manufacturers with a new basis for remanufacturing decisions.

The purpose of this paper is to identify the key determinants of the information value of enterprises’ micro-blogs, drawing on the consumer’s perspective. This paper examines the effects of such information value on consumers’ purchase intention through the building of online brand equity. The paper also investigates how perceived usefulness intervenes in the relationship between micro-blog information value and consumer purchase intention.

The proposed research model is examined empirically using a survey of 315 users of the Sina micro-blog. The statistical analysis applies a method based on variance using partial least squares.

The results show that online retailers’ micro-blog posts, which are characterized by informativeness and persuasiveness as perceived by customers, positively impact online retailers’ brand equity, which in turn influences consumer purchase intention. In addition, perceived information usefulness is found to be an important contextual factor that moderates the relationship between perceived persuasiveness and online retailer brand equity.

This work adds significance to the literature by extending the research on micro-blog marketing and also provides practical recommendations for online retailers on the operation of micro-blogs.

This paper aims to verify the inhibition of the hydrogen permeation effect of the coating and to quantitatively and qualitatively characterize the coating-induced stress.

By means of slow strain rate tensile testing (SSRT) in humid air, thickness measurement, fracture morphology, cross-section morphology and surface morphology, hydrogen content measurements, flow stress difference method.

The results demonstrate that the mechanism of the inhibition of hydrogen embrittlement by the coating is mainly attributed to the repression of hydrogen permeation and the additional coating-induced compressive stress.

It is proven that the micro-arc oxidation (MAO) coating does inhibit hydrogen entry into the alloy, and the stress induced by the MAO coating is compressive stress, which can restrain the hydrogen embrittlement of the alloy. Therefore, the mechanism of the inhibition of hydrogen embrittlement is dominated by the mechanisms of both hydrogen permeation inhibition and coating-induced stress.

The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.

First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.

Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.

The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.

The purpose of this is to study the effects of organic sealing on the structure and performance of the micro-arc oxidation (MAO) film of 7075 aluminum alloy.

The 7075 aluminum alloy was treated by micro-arc oxidation technology, then the MAO films were sealed by polyvinylidene fluoride (PVDF) solutions with different concentrations to forms a MAO/PVDF composite coating on the surface of the 7075 aluminum alloy matrix.

The results show that the MAO/PVDF film thickness increased to 24.8 um. When the PVDF concentration was 8 g/L, and the sealed film reached best corrosion resistance and wear resistance.

The effects of different concentrations of PVDF on microarc oxidation properties of 7075 aluminum alloy were studied.

This paper seeks to discuss the genealogical sources for Chinese immigrants as well as the settlement of Chinese in the USA and the historical evolution of Chinese names, their origins, arrangement and development. It aims to cover the origins of various classes of Chinese surnames, followed by the content description of a traditional genealogical book for jiapu.

The paper researches the various ways that a Chinese person can find out about their ancestry.

The paper reveals the roles of libraries, including serving the needs of patrons interested in genealogical research, preserving and interpreting information through oral and family history projects and collaborating with other libraries through interlibrary loan, document delivery, library consortia, collection management and international resource‐sharing.

The study provides information on where and how to locate the genealogical resources for researching the genealogy of a Chinese family.

The paper analyzes the value of genealogical research as a documentary source for population history, life expectancy in a clan, marriages and family connections, as well as lineage organizations and inter‐lineage relations.