A comparative study of two approaches for supporting optimal network location queries

Given a set S of sites and a set O of weighted objects, an optimal location query finds the location(s) where introducing a new site maximizes the total weight of the objects that are closer to the new site than to any other site. With such a query, for instance, a franchise corporation (e.g., McDonald’s) can find a location to open a new store such that the number of potential store customers (i.e., people living close to the store) is maximized. Optimal location queries are computationally complex to compute and require efficient solutions that scale with large datasets. Previously, two specific approaches have been proposed for efficient computation of optimal location queries. However, they both assume p-norm distance (namely, L₁ and L₂/Euclidean); hence, they are not applicable where sites and objects are located on spatial networks. In this article, we focus on optimal network location (ONL) queries, i.e., optimal location queries in which objects and sites reside on a spatial network. We introduce two complementary approaches, namely EONL (short for Expansion-based ONL) and BONL (short for Bound-based ONL), which enable efficient computation of ONL queries with datasets of uniform and skewed distributions, respectively. Moreover, with an extensive experimental study we verify and compare the efficiency of our proposed approaches with real world datasets, and we demonstrate the importance of considering network distance (rather than p-norm distance) with ONL queries.     

A Convenient Method for Preparation of Amphiphilic Monomethoxypoly (Ethylene Glycol)–Polystyrene Diblock Copolymer by NMRP Technique

Amphiphilic block copolymers are macromolecular compounds of great importance from both fundamental scientific and many technological point of views for a large variety of applications. Amphiphilic diblock copolymer containing segments of monomethoxypoly(ethylene glycol) and polystyrene (MPEG-b-PS) was synthesised by a convenient method for preparation of macroinitiator MPEG-TEMPO for ‘living’ free radical polymerization (NMRP technique). Initially, derivative of MPEG with chlorine function has been prepared in an one-step reaction with thionyl chloride. 1-hydroxy-2,2,6,6-tetramethyl-piperidine (TEMPO-OH) obtained by reduction of 2,2,6,6-tetramethyl-piperidinyl-1-oxy (TEMPO) with sodium ascorbate was coupled with chlorinated MPEG to yield the macroinitiator MPEG terminated with a TEMPO unit (MPEG-TEMPO), which was further used to prepare the diblock copolymer MPEG-b-PS of styrene. The product was purified and identified by ¹H NMR, GPC and, FT-IR.     

Resource discovery approaches in cloudIoT: a systematic review

The Journal of Supercomputing - The cloud of things (CloudIoT) represents a general system of supporting infrastructure for storing and processing information gathered from smart objects and their...     

Thermo-mechanical vibration analysis of rotating nonlocal nanoplates applying generalized differential quadrature method

In this study, thermal and small-scale effects on the flapwise bending vibrations of a rotating nanoplate, which can be the basis of nano-turbine design, have been analyzed. The nano-turbine is made of an orthotropic nanoplate with a setting angle that is modeled based on the classical plate theory (CPT) with cantilever boundary conditions. The axial forces are also included in the model as the true spatial variation due to the rotation and temperature change. The governing equations and boundary conditions are derived according to Hamilton's principle and the governing equations are solved with the aid of the generalized differential quadrature method. The effects of small-scale parameter, nondimensional angular velocity, temperature change, and setting angles in the first four nondimensional frequencies are discussed. Due to the consideration of the rotating effects, results of this study are applicable in nano-machines, such as nano-motors, nano-rotor, and other rotating nano-structures. Also, by considering the effect of thermal loading on rotation of a nanoplate, the results are useful in the design of nano-turbines.     

Creep analysis of fibre reinforced adhesives in single lap joints—Experimental study

In this paper, the effect of reinforcing the adhesive on the creep behaviour of single lap joints was studied experimentally. The reinforcement was in the form of fibre and three types of fibres namely aramid, carbon and glass were used. The test was performed at a temperature above the glass transition temperature of the adhesive. The effect of fibre orientation was also investigated. The failure time and initial strain for all the specimens were evaluated and compared to the un-reinforced adhesive joint. According to the results, adding fibres in the bondline considerably affects both the initial strain and the failure time and these effects are dependent on the fibre type and orientations. The fracture surfaces of the specimens were also studied to investigate the failure mechanisms of the reinforced adhesive in creep. The fibre breakage was observed along with adhesive and cohesive failures.     

Improving the functionality of biodegradable food packaging materials via porous nanomaterials

Non-biodegradability and disposal problems are the major challenges associated with synthetic plastic packaging. This review article discusses a new generation of biodegradable active and smart packaging based on porous nanomaterials (PNMs), which maintains the quality and freshness of food products while meeting biodegradability requirements. PNMs have recently gained significant attention in the field of food packaging due to their large surface area, peculiar structures, functional flexibility, and thermal stability. We present for the first time the recently published literature on the incorporation of various PNMs into renewable materials to develop advanced, environmentally friendly, and high-quality packaging technology. Various emerging packaging technologies are discussed in this review, along with their advantages and disadvantages. Moreover, it provides general information about PNMs, their characterization, and fabrication methods. It also briefly describes the effects of different PNMs on the functionality of biopolymeric films. Furthermore, we examined how smart packaging loaded with PNMs can improve food shelf life and reduce food waste. The results indicate that PNMs play a critical role in improving the antimicrobial, thermal, physicochemical, and mechanical properties of natural packaging materials. These tailor-made materials can simultaneously extend the shelf life of food while reducing plastic usage and food waste.     

Effect of fortification with asparagus powder on the qualitative properties of processed cheese

The qualitative properties of processed cheese (PC) fortified with different levels of asparagus powder (AP) (0.5%, 1% and 1.5% wt/wt) were evaluated during storage. AP decreased the pH and lipolysis indexes and increased the phenolic content, antioxidant activity and proteolysis of the processed cheeses. AP made the structure of the cheese more elastic, increased the rigidity and decreased the spreadability compared with the control sample, which corresponded to the results obtained using dynamic oscillatory rheometry. The results showed that AP as a rich source of bioactive components could be used for the fortification of processed cheeses.     

Exergoeconomic and environmental investigation of an innovative poly-generation plant driven by a solid oxide fuel cell for production of electricity,cooling, desalinated water,and hydrogen

Fuel cell and renewable-based poly-generation plants (PGPs) are proven as advanced technologies for multiple generation purposes. To limit the greenhouse gas emissions, an innovative PGP generating electricity, cooling, desalinated water, and hydrogen is proposed in the current study. The system consists of a solid oxide fuel cell as a prime mover integrated with a gas turbine, a biomass combustion chamber, an organic Rankine cycle, an ejector refrigeration cycle, a desalination unit, and a proton exchange membrane electrolyzer integrated with solar collectors. As the most effective tools for performance evaluation, exergoeconomic, and environmental analyses have been applied. The system produces electricity of 4.4 MW, refrigeration capacity of 0.16 MW, and desalinated water of 0.96 kg/s. The attained freshwater enters the electrolyzer during 12 daylight hours, leading to hydrogen and sanitary water generation with the values of 1.55 g/s and 0.94 kg/s, respectively. The cost per unit exergy and the total cost rate of the products are 11.28 $/GJ, 223 $/h, correspondingly. Carbon dioxide emission of the system is estimated to be 10.79 kmol/MWh. According to the evaluation, the total cost rate increases with increasing current density and fuel cell inlet temperature and decreasing fuel utilization factor.