Model-driven development of composite context-aware web applications

Context-awareness constitutes an essential aspect of services, especially when interaction with end-users is involved. In this paper a solution for the context-aware development of web applications consisting of web services is presented. The methodology proposes a model based approach and advocates in favour of a complete separation of the web application functionality from the context adaptation at all development phases (analysis, design, implementation). In essence, context adaptation takes place on top of and is transparent to the web application business functionality. Starting from UML diagrams of independent web services and respective UML context models, our approach can produce a functional composite context-aware application. At execution level this independence is maintained through an adaptation framework based on message interception.     

Vibrational spectroscopic study on the origin of stress oscillation during step-wise stretching in poly(ethylene terephthalate)

The origin of the phenomenon of stress oscillation during step-wise stretching at room temperature for amorphous poly(ethylene terephthalate) (PET) was investigated using vibrational spectroscopy. For the first time, transmission Fourier transform infrared (FT-IR), attenuated total reflection (ATR) FT-IR, and micro-Raman spectroscopies were used in order to investigate the correlation of the orientation of the molecular chains, their conformational transformations, and the appearance of stress-induced crystallization to the phenomenon of stress oscillation during the step-wise stretching procedure. The phenomenon of stress oscillation occurs when amorphous PET is exposed to mechanical stress during which the extension rate is increased in a step-wise manner. This phenomenon leads to the formation of a pattern of opaque and transparent stripes ('striated' or oscillating region), clearly distinguished from the unstretched ('bulk') and the 'necking' regions. Both infrared and Raman spectroscopic investigations revealed that the main conformational transformations and a significant increase of the crystallinity occur simultaneously in the 'striated' region. Polarized infrared experiments showed the presence of increased molecular orientation, which is more profound for the 'intense striated' region. Finally, micro-Raman spectroscopy allowed the study of opaque and transparent stripes individually and showed that the opaque stripes are more crystalline. Thus, our findings provide conclusive experimental support for the theory, which directly correlates the appearance of the stress-oscillation phenomenon with the induction of crystallinity and heat release and is based on Barenblatt's model. Our study also provides new conformational assignments for the infrared bands in PET for the high-frequency region from 3200 to 3800 cm(-1). Specifically, the bands at 3336 cm(-1) and at 3298 cm(-1) have been attributed to the trans and gauche conformations, respectively.     

Organizational socialization: Its content and consequences.

Content dimensions of the socialization domain were defined to determine relationships between learning particular features of a job/organization and the process and outcomes of socialization. Six socialization dimensions (performance proficiency, politics, language, people, organizational goals/values, and history) were supported by a factor analysis on data from 594 full-time professionals. The socialization process was then examined by comparing 3 groups of respondents who did not change jobs, changed jobs within the organization, or changed jobs and organizations. Results showed these groups had significantly different response patterns on all dimensions. Finally, relationships between socialization content and career outcomes showed the dimensions accounted for more variance in all criteria than typical tenure operationalizations of socialization. Furthermore, socialization changes were significantly related to changes in career outcomes for 1-, 2-, and 3-yr time intervals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A longitudinal investigation of newcomer expectations, early socialization outcomes, and the moderating effects of role development factors.

This longitudinal study examined hypothesized moderating effects of role development on the link between unmet expectations and socialization outcomes. Data were collected from 248 new hires before organizational entry and at an average of 4 weeks after entry. Three role expectations, conflict, clarity, and acceptance, were measured at both data collections. Two role development constructs, leader-member exchange (LMX) and team-member exchange (TMX), and three socialization outcomes, organizational commitment, turnover intention, and job satisfaction, were measured after entry. Results showed that met expectations, LMX, and TMX were significant predictors of all outcomes. In addition, LMX and TMX significantly moderated several relationships, such that favorable role development relationships with supervisors or work groups ameliorated the negative effects of unmet expectations. Research and applied implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rare Earths Outlook 2019:EV Production to Drive Demand

<正>Of the 17 rare earth elements (REEs), some have proven rarer than others. Neodymium and praseodymium(NdPr), two metals instrumental to the rapidly expanding green energy and electric vehicle (EV) sectors, saw the greatest demand and price movement in 2018.     

Study of thermomechanical,structural and antibacterial properties of poly(lactic acid) reinforced with graphene oxide nanoparticles via melt mixing

Addition of graphene oxide (GO) to poly(l ‐lactic acid) (PLLA) offers an alternative approach for tuning its crystallinity, improving its mechanical properties and transfusing an antibacterial behavior. GO/PLLA nanocomposites were prepared by melt extrusion, thus avoiding the potentially toxic, for biomedical applications, residue of organic solvents. Fourier transform infrared spectroscopy verified the formation of intermolecular hydrogen bonds. Using differential scanning calorimetry experiments concerning the isothermal crystallization of PLLA and PLLA containing 0.4 wt% GO, a two‐dimensional disc‐like geometry of crystal growth was determined, whereas at 125 and 130 °C the nanocomposite developed three‐dimensional spherulitic growth. Higher crystallization rate constant values suggest that the incorporation of 0.4 wt% GO accelerated the crystallization of PLLA. The lowest crystallization half‐time for PLLA was observed at 115 °C, while at 110 °C GO caused its highest decrease, accompanied by the highest increase in melting enthalpy (ΔH_m), as compared to that of PLLA, after completion of isothermal crystallization. Their ΔH_m values increased with T_ic, whereas multiple melting peaks transited to a single one with increasing T_ic. GO improved the PLLA thermal stability, tensile strength and Young's modulus. Incorporation of 0.8 wt% GO endowed PLLA with another potential application as a biomaterial since the derived composite presented good thermomechanical properties and effective prohibition of Escherichia coli bacteria attachment and proliferation. This effect was more prominent under simulated sunlight exposure than in the dark. The preparation method did not compromise the intrinsic properties of GO. © 2020 Society of Chemical Industry     

Assessment of public acceptance and willingness to pay for renewable energy sources in Crete

The aim of this study is to analyse and to evaluate the citizens’ public acceptance and willingness to pay (WTP), for Renewable Energy Sources (RES) in Crete. For this purpose a contingent valuation study was conducted, using a double bound dichotomous choice format to elicit people's WTP and factors affecting it. Residents of 1440 households all over Crete were interviewed face-to-face. Major conclusions can be used as a basis for sustainable energy planning, for policies and the formulation of awareness campaigns and for RES investment programs and projects in order to prepare implementation conditions and enhance public acceptance of renewable energy investments and programmes. Mean WTP per household was found to be 16.33€ to be paid quarterly as an additional charge on the electricity bill. Larger willingness to pay was reported by those with high family income and residence size, those having a higher level of energy information and awareness concerning climatic change, those who have invested in some energy saving measures, and those who suffer from more electricity shortages than others.