a b s t r a c tThe member selection problem is an important aspect of the formation of cross-functional teams (CFTs). Selecting suitable members from a set of candidates will facilitate the successful task accomplishment. In the existing studies of member selection, the individual performance concerning a single candidate is mostly used, whereas the collaborative performance associating with a pair of candidates is overlooked. In this paper, as a solution to this problem, we propose a method for member selection of CFTs, where both the individual performance of candidates and the collaborative performance between candidates are considered. In order to select the desired members, firstly, a multi-objective 0-1 programming model is built using the individual and collaborative performances, which is an NP-hard problem. To solve the model, we develop an improved nondominated sorting genetic algorithm II (INSGA-II). Furthermore, a real example is employed to illustrate the suitability of the proposed method. Additionally, extensive computational experiments to compare INSGA-II with the nondominated sorting genetic algorithm II (NSGA-II) are conducted and much better performance of INSGA-II is observed.

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Problem definition: We have witnessed a rapid rise of on-demand platforms, such as Uber, in the past few years. Although these platforms allow workers to choose their own working hours, they have limited leverage in maintaining availability of workers within a region. As such, platforms often implement various policies, including offering financial incentives and/or communicating customer demand to workers in order to direct more workers to regions with shortage in supply. This research examines how behavioral biases such as regret aversion may influence workers’ relocation decisions and ultimately the system performance. Academic/practical relevance: Studies on on-demand platforms often assume that workers are rational agents who make optimal decisions. Our research investigates workers’ relocation decisions from a behavioral perspective. A deeper understanding of workers’ behavioral biases and their causes will help on-demand platforms design appropriate policies to increase their own profit, worker surplus, and the overall efficiency of matching supply with demand. Methodology: We use a combination of behavioral modeling and controlled laboratory experiments. We develop analytical models that incorporate regret aversion to produce theoretical predictions, which are then tested and verified via a series of controlled laboratory experiments. Results: We find that regret aversion plays an important role in workers’ relocation decisions. Regret-averse workers are more willing to relocate to the supply-shortage zone than rational workers. This increased relocation behavior, however, is not sufficient to translate to a better system performance. Platform interventions, such as demand information sharing and dynamic wage bonus, can help further improve the system. We find that workers’ regret-aversion behavior may lead to an increased profit for the platform, a higher surplus for the workers, and an improved demand-supply matching efficiency, thus benefiting the entire on-demand system. Managerial implications: Our research emphasizes the importance and necessity of incorporating workers’ behavioral biases such as regret aversion into the policy design of on-demand platforms. Policies without considering the behavioral aspect of workers’ decision may lead to lost profit for the platform and reduced welfare for workers and customers, which may ultimately hurt the on-demand business.

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The effects of cold work on the pitting corrosion resistance of a nickel-free high-nitrogen stainless steel in chloride solution have been investigated by electrochemical tests, surface chemical analysis, immersion tests, and microscopic observations. Potentiodynamic polarization revealed that pitting resistance was degraded by cold work as convinced by the decreased critical pitting potential. This could be due to a less compact and protective anodic passive film based on the results of electrochemical impedance spectroscopy, Mott-Schottky measurement, and X-ray photoelectron spectroscopy analysis. The growth of such an imperfect passive film could be attributed to a high density of deformation bands and other defects introduced by cold work. Scanning electron microscopy observation of the pitted specimens after polarization tests showed no obvious change in size and density of corrosion pits with increasing cold work level, whereas immersion tests showed varied pit density with cold work although the average size of pits did not increase linearly as a function of cold work level. The effects of cold work on the characteristics of passive films are discussed.The beneficial effects of nitrogen on the properties of highalloyed steels have led to a widespread development of highnitrogen stainless steels ͑HNSSs͒ owing to recent advances in processing technologies. 1-3 Nitrogen as an alloying element causes several beneficial effects on the properties of steels, in particular, those related to an excellent combination of high yield strength and good fracture toughness. 1 Nitrogen is also a strong austenitestabilizing element and is expected to substitute for nickel, which is expensive and causes an allergic reaction in human skin. Moreover, nitrogen alloying, especially together with molybdenum, improves resistance to localized corrosion, in general, and resistance to general corrosion in some environments. Therefore, the austenitic HNSSs constitute a group of promising structural materials that possess a favorable combination of mechanical and corrosion-resistance properties.With these increasing demands, it is necessary to investigate the pitting resistance of the HNSSs. Thus far, a number of possible mechanisms by which nitrogen improves the localized corrosion resistance have been reported. 4-7 Cold work is unavoidable for the fabrication of stainless steel ͑SS͒ components. It might affect the pitting corrosion resistance of SSs because deformation substructures, such as planar dislocation arrays 1,8 and deformation twinning, 9 could be introduced. Several investigations have reported the role of cold work on the localized corrosion resistance of SSs. 10-17 Kamachi Mudali et al. 10 have reported that the pitting corrosion resistance of a nitrogen-bearing 316 SS was improved first by cold work in neutral chloride medium and then reduced beyond 20% cold work. Peguet et al. 11 have reported the different role of cold work on the pitting corrosion resistance at different pitting stages, including pit initiation, prop...

The microstructural evolution of 18Cr18Mn2Mo0.77N high nitrogen austenitic stainless steel in aging treatment was investigated by optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that hexagonal intergranular and cellular Cr 2 N with a=0.478 nm and c=0.444 nm and body-centered cubic intermetallic χ phase with a=0.892 nm precipitate gradually in the isothermal aging treatment. The matrix nitrogen depletion due to the intergranular Cr 2 N precipitation induces the decay of Vickers hardness, and the formation of cellular Cr 2 N and χ phase causes the increase in the values. The impact toughness presents a monotonic decrease and SEM morphologies show the leading brittle intergranular fracture. The tensile strength and elongation deteriorate obviously except for the sample aged for 1 h in yield strength. Stress concentration occurs when the matrix dislocations pile up at the precipitation and matrix interfaces, and the interfacial dislocations may become precursors to the misfit dislocations, which can form small cleavage steps and accelerate the formation of cracks.