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When new items are released, it is necessary to promote these items. In this situation, a recommender system specializing in new items help item providers find potential customers. This study aims to suggest a Min-Max distance-based preference boundary, and to develop a preference boundary-based recommender procedure applied for recommending new items. The basic principle is that if a new item belongs within the preference boundary of a target customer, then it is evaluated to be preferred by the customer. The new item recommendation procedure is organized in the following two phases. The first phase defines each customer's preference boundary based on min-max distance, and the second phase decides the target customer set for recommending new items. In this research, customer' preferences and item characteristics including new items are represented in a feature space. And the scope of boundary of the target customer's preference is extended to those of neighbors'. Diverse algorithms are suggested for the procedure, and their effectiveness scores are measured and compared through a series of experiments with a real mobile image transaction data set. The experiment results are compared, and discussions about the results are also given with a further research opportunity.

Nano-size silica particles were functionalized with vinyl isocyanate and subsequently UV cured to synthesize polyurethane–silica nano-composites which were tested for mechanical, dynamic mechanical, cross-link density, contact angle and XPS. The modified silica provides composites with cross-links that are pinned at the surfaces and which effectively reinforce the materials mechanically as well as thermally.

To modify the surface of UV cured polyurethane dispersion (UV-PUD), fluorinated PU called surface modifying agent (SMA) was blended with base PU prior to dispersion in water. X-ray photoelectron spectroscopy (XPS) and contact angle measurements showed that surfaces of dispersion cast film are significantly enriched with fluorine groups. Atomic force microscopy (AFM) showed that surface was roughened with the addition of SMA, which provided possible mechanism of increased water resistance as well as low friction coefficient of the film. On the other hand, hardness, mechanical and dynamic mechanical properties indicated that the bulk properties are marginally altered by the additive amount of SMA.

Using a sol–gel process nanometer-scale silicas were incorporated into waterborne polyurethanes (PUs) which were synthesized from isophoronediisocyanate (IPDI), poly(tetramethyleneglycol) (PTMG), dimethylolpropionic acid (DMPA), triethylamine (TEA), diethylenetriamine (DETA) and 3-aminopropyltriethoxysilane as coupling agent. Thermal, mechanical, and dynamic mechanical properties of the hybrid composite have been studied. 29Si-NMR spectra gave evidence of condensation reaction between silica and silanes encaping the PU prepolymers, whereas transmission electron microscopy (TEM) showed the high connectivity of hybrid composites. It was found that greater thermal and mechanical properties of waterborne PU/silica hybrid composite were obtained when chemical networks were formed between PU and silica.

The objective of this study is to examine the effects of regulation policy on online gambling, an increasingly popular type of entertainment in the online game industry. Prior information systems (IS) studies on online game focus primarily on user behavior. However, there is a growing need to investigate the effects of regulation policy on dynamic changes of games or service providers instead of ad hoc heuristic approaches on individual behavior. Going beyond the approaches of previous studies, this study empirically test the regulation policy effect with three theoretical perspectives: social influence, prior experience and perceived switching cost. A vector autoregression (VAR) methodology is used to forecast game usage and to model several patterns of the co-movement of online games. Evidence is also provided of strong Granger-causal interdependencies within games and service providers. This study provides one of the first empirical evidences that examine the effects of regulation policies on online game. In research methodology aspect, this study also introduce an exposition of VAR methodology in IS research. Therefore, it provides advanced knowledge on gambling behavior and helps develop suitable regulation policy to protect users of online gambling as well as to satisfy policy makers.

As new items are frequently released nowadays, item providers and customers need the recommender system which is specialized in recommending new items. Because most of previous approaches for recommender system have to rely on the usage history of customers, collaborative filtering is not directly applicable to solve the new item problem. Therefore they have suggested content-based recommender system using feature values of new items. However it is not sufficient to recommend new items. This research aims to suggest hybrid recommendation procedures based on preference boundary of target customer. We suggest TC, BC, and NC algorithms to determine the preference boundary. TC is an algorithm developed from contents-based filtering, whereas BC and NC are algorithms based on collaborative filtering, which incorporates neighbors, similar customers to a target customer. We evaluate the performances of suggested algorithms with real mobile image transaction data set. Experimental test results that the performances of BC and NC is better than that of TC, which means that the suggested hybrid procedures are more effective than the content-based approach.

Thermoresponsive polyurethane (PU)–silica nanocomposites were synthesized by incorporating silica particles as multifunctional cross-linkers into the PUvia sol–gel reactions. At 2 wt% silica, the composites showed over 99% shape fixity and shape recovery up to the 4th thermomechanical cycle along with outstanding mechanical properties in their rubbery as well as glass state. The incorporated nano-sized silica particles gave dual effects of multifunctional chemical cross-links and reinforcing fillers. The properties were favorably compared with those of uncross-linked PU and conventionally cross-linked PU.