bluuebunny/crossref_metadata_2025 huggingface dataset:
Detuning Minimization of Induction Motor Drive System for Alternative Energy Vehicles
Authors: Rehman Habibur
Published: August 2015

This paper evaluates different types of AC machines and various control techniques for their suitability for the drive system of Alternative Energy Vehicles (AEV). An Indirect Field Oriented (IFO) drive system for the AEV application is chosen and its major problem of detuning is addressed by designing an offline and an online rotor resistance adaptation technique. The offline scheme sets the slip gain at various operating conditions based on the fact that if the rotor resistance is set correctly and field orientation is achieved, then there should be a linear relationship between the torque current and the output torque. The online technique is designed using Model Reference Adaptive System (MRAS) for the rotor resistance adaptation. For an ideal field oriented machine, the rotor flux along the q-axis should be zero. This condition acts as a reference model for the proposed MRAS scheme. The current model flux observer in the synchronous frame of reference is selected as an adjustable model and its rotor resistance is tuned so that the flux along the q-axis becomes zero. The effectiveness of the offline tuning scheme is evident through performance validation of the drive system, which is implemented in a real Ford vehicle. The experimental results obtained while driving the test vehicle are included in the paper while the proposed online scheme is validated on a 3.75 kW prototype induction motor.
Warm and Fertile Sub-Humid Conditions Enhance Litterfall to Sustain High Soil Respiration Fluxes in a Mediterranean Cork Oak Forest
Authors: Zribi Lobna , Mouillot Florent , Gharbi Fatma , Ourcival Jean-Marc , Hanchi Belgacem
Published: August 2015

Soil respiration is a major component of the global carbon budget and Mediterranean ecosystems have usually been studied in locations with shallow soils, mild temperatures, and a prolonged dry season. This study investigates seasonal soil respiration rates and underlying mechanisms under wetter, warmer, and more fertile conditions in a Mediterranean cork oak forest of Northern Tunisia (Africa), acknowledged as one of the most productive forests in the Mediterranean basin. We applied a soil respiration model based on soil temperature and relative water content and investigated how ecosystem functioning under these favorable conditions affected soil carbon storage through carbon inputs to the soil litter. Annual soil respiration rates varied between 1774 gC m−2 year−1 and 2227 gC m−2 year−1, which is on the highest range of observations under Mediterranean climate conditions. We attributed this high soil carbon flux as a response to favorable temperatures and soil water content, but this could be sustained only by a small carbon allocation to roots (root/shoot ratio = 0.31–0.41) leading to a large allocation to leaves with a multiannual leaf production, enhanced annual twig elongation (11.5–28.5 cm) with a reduced leaf life span (<1 year) maintaining a low LAI (1.68–1.88) and generating a high litterfall (386–636 gC m−2 year−1). Thus, the favorable climatic and edaphic conditions experienced by these Mediterranean cork oak forests drove high soil respiration fluxes which balanced the high carbon assimilation leading to a relatively small overall contribution (10.96–14.79 kgC m−2) to soil carbon storage.
Low Dose Gamma Irradiation Does Not Affect the Quality or Total Ascorbic Acid Concentration of “Sweetheart” Passionfruit (Passiflora edulis)
Authors: Golding John , Blades Barbara , Satyan Shashirekha , Spohr Lorraine , Harris Anne , Jessup Andrew , Archer John , Davies Justin , Banos Connie
Published: August 2015

Passionfruit (Passiflora edulis, Sims, cultivar “Sweetheart”) were subject to gamma irradiation at levels suitable for phytosanitary purposes (0, 150, 400 and 1000 Gy) then stored at 8 °C and assessed for fruit quality and total ascorbic acid concentration after one and fourteen days. Irradiation at any dose (≤1000 Gy) did not affect passionfruit quality (overall fruit quality, colour, firmness, fruit shrivel, stem condition, weight loss, total soluble solids level (TSS), titratable acidity (TA) level, TSS/TA ratio, juice pH and rot development), nor the total ascorbic acid concentration. The length of time in storage affected some fruit quality parameters and total ascorbic acid concentration, with longer storage periods resulting in lower quality fruit and lower total ascorbic acid concentration, irrespective of irradiation. There was no interaction between irradiation treatment and storage time, indicating that irradiation did not influence the effect of storage on passionfruit quality. The results showed that the application of 150, 400 and 1000 Gy gamma irradiation to “Sweetheart” purple passionfruit did not produce any deleterious effects on fruit quality or total ascorbic acid concentration during cold storage, thus supporting the use of low dose irradiation as a phytosanitary treatment against quarantine pests in purple passionfruit.
Glucagon Like Peptide-1 (GLP-1) Modulates OVA-Induced Airway Inflammation and Mucus Secretion Involving a Protein Kinase A (PKA)-Dependent Nuclear Factor-κB (NF-κB) Signaling Pathway in Mice
Authors: Zhu Tao , Wu Xiao-ling , Zhang Wei , Xiao Min
Published: August 2015

Asthma is a common chronic pulmonary inflammatory disease, featured with mucus hyper-secretion in the airway. Recent studies found that glucagon like peptide-1 (GLP-1) analogs, including liraglutide and exenatide, possessed a potent anti-inflammatory property through a protein kinase A (PKA)-dependent signaling pathway. Therefore, the aim of current study was to investigate the value of GLP-1 analog therapy liraglutide in airway inflammation and mucus secretion in a murine model of ovalbumin (OVA)-induced asthma, and its underlying molecular mechanism. In our study, BALB/c mice were sensitized and challenged by OVA to induce chronic asthma. Pathological alterations, the number of cells and the content of inflammatory mediators in bronchoalveolar lavage fluid (BALF), and mucus secretion were observed and measured. In addition, the mRNA and protein expression of E-selectin and MUC5AC were analyzed by qPCR and Western blotting. Then, the phosphorylation of PKA and nuclear factor-κB (NF-κB) p65 were also measured by Western blotting. Further, NF-κB p65 DNA binding activity was detected by ELISA. OVA-induced airway inflammation, airway mucus hyper-secretion, the up-regulation of E-selectin and MUC5AC were remarkably inhibited by GLP-1 in mice (all p < 0.01). Then, we also found that OVA-reduced phosphorylation of PKA, and OVA-enhanced NF-κB p65 activation and NF-κB p65 DNA binding activity were markedly improved by GLP-1 (all p < 0.01). Furthermore, our data also figured out that these effects of GLP-1 were largely abrogated by the PKA inhibitor H-89 (all p < 0.01). Taken together, our results suggest that OVA-induced asthma were potently ameliorated by GLP-1 possibly through a PKA-dependent inactivation of NF-κB in mice, indicating that GLP-1 analogs may be considered an effective and safe drug for the potential treatment of asthma in the future.
Visualization of Biosurfactant Film Flow in a Bacillus subtilis Swarm Colony on an Agar Plate
Authors: Kim Kyunghoon , Kim Jung
Published: August 2015

Collective bacterial dynamics plays a crucial role in colony development. Although many research groups have studied the behavior of fluidic swarm colonies, the detailed mechanics of its motion remains elusive. Here, we developed a visualization method using submicron fluorescent beads for investigating the flow field in a thin layer of fluid that covers a Bacillus subtilis swarm colony growing on an agar plate. The beads were initially embedded in the agar plate and subsequently distributed spontaneously at the upper surface of the expanding colony. We conducted long-term live cell imaging of the B. subtilis colony using the fluorescent tracers, and obtained high-resolution velocity maps of microscale vortices in the swarm colony using particle image velocimetry. A distinct periodic fluctuation in the average speed and vorticity of flow in swarm colony was observed at the inner region of the colony, and correlated with the switch between bacterial swarming and growth phases. At the advancing edge of the colony, both the magnitudes of velocity and vorticity of flow in swarm colony were inversely correlated with the spreading speed of the swarm edge. The advanced imaging tool developed in this study would facilitate further understanding of the effect of micro vortices in swarm colony on the collective dynamics of bacteria.
Doing “Life”: A Glimpse into the Long-Term Incarceration Experience
Authors: Willis Anthony , Zaitzow Barbara
Published: August 2015

“Life means life” is a mantra of elected state officials who would rather spend already-compromised state budgets on increasing the use of imprisonment as a punishing tool rather than being viewed by their constituents as “soft on crime”. As a result of tough-on-crime initiatives, approximately 160,000 out of 2.2 million inmates being held in jails and prisons in the United States are serving life sentences. While surviving imprisonment is a challenge for most individuals, prisoners who serve long sentences—including “life”—have different adaptation mechanisms, and for them, adaptation is a longer, more complex process. Further, while persons serving life sentences include those who present a serious threat to public safety, they also include those for whom the length of sentence is questionable. In particular, life without parole (LWOP) sentences often represent a misuse of limited correctional resources and discount the capacity for personal growth and rehabilitation that comes with the passage of time. The purpose of this article is to explore the “doing life” experiences of a man who has chosen to redirect the focus of his life by transforming himself and helping others.
Interaction between Marine-Derived n-3 Long Chain Polyunsaturated Fatty Acids and Uric Acid on Glucose Metabolism and Risk of Type 2 Diabetes Mellitus: A Case-Control Study
Authors: Li Kelei , Wu Kejian , Zhao Yimin , Huang Tao , Lou Dajun , Yu Xiaomei , Li Duo
Published: August 2015

The present case-control study explored the interaction between marine-derived n-3 long chain polyunsaturated fatty acids (n-3 LC PUFAs) and uric acid (UA) on glucose metabolism and risk of type 2 diabetes mellitus (T2DM). Two hundred and eleven healthy subjects in control group and 268 T2DM subjects in case group were included. Plasma phospholipid (PL) fatty acids and biochemical parameters were detected by standard methods. Plasma PL C22:6n-3 was significantly lower in case group than in control group, and was negatively correlated with fasting glucose (r = −0.177, p < 0.001). Higher plasma PL C22:6n-3 was associated with lower risk of T2DM, and the OR was 0.32 (95% confidence interval (CI), 0.12 to 0.80; p = 0.016) for per unit increase of C22:6n-3. UA was significantly lower in case group than in control group. UA was positively correlated with fasting glucose in healthy subjects, but this correlation became negative in T2DM subjects. A significant interaction was observed between C22:6n-3 and UA on fasting glucose (p for interaction = 0.005): the lowering effect of C22:6n-3 was only significant in subjects with a lower level of UA. In conclusion, C22:6n-3 interacts with UA to modulate glucose metabolism.
Autodisplay of Human Hyaluronidase Hyal-1 on Escherichia coli and Identification of Plant-Derived Enzyme Inhibitors
Authors: Orlando Zoya , Lengers Isabelle , Melzig Matthias , Buschauer Armin , Hensel Andreas , Jose Joachim
Published: August 2015

Hyaluronan (HA) is the main component of the extracellular matrix (ECM). Depending on its chain size, it is generally accepted to exert diverse effects. High molecular weight HA is anti-angiogenic, immunosuppressive and anti-inflammatory, while lower fragments are angiogenic and inflammatory. Human hyaluronidase Hyal-1 (Hyal-1) is one of the main enzymes in the metabolism of HA. This makes Hyal-1 an interesting target. Not only for functional and mechanistic studies, but also for drug development. In this work, Hyal-1 was expressed on the surface of E. coli, by applying Autodisplay, to overcome formation of inactive “inclusion bodies”. With the cells displaying Hyal-1 an activity assay was performed using “stains-all” dye. Subsequently, the inhibitory effects of four saponins and 14 plant extracts on the activity of surface displayed Hyal-1 were evaluated. The determined IC50 values were 177 µM for glycyrrhizic acid, 108 µM for gypsophila saponin 2, 371 µM for SA1657 and 296 µM for SA1641. Malvae sylvestris flos, Equiseti herba and Ononidis radix extracts showed IC50 values between 1.4 and 1.7 mg/mL. In summary, Autodisplay enabled the expression of functional human target protein Hyal-1 in E. coli and facilitated an accelerated testing of potential inhibitors.
Identification and Antioxidant Properties of Phenolic Compounds during Production of Bread from Purple Wheat Grains
Authors: Yu Lilei , Beta Trust
Published: August 2015

Phenolic profiles and antioxidant properties of purple wheat varieties were investigated to document the effects of bread-making. Bread crust and crumb along with samples collected after mixing, 30 min fermenting, 65 min fermenting, and baking were examined. Free phenolic content (105.4 to 113.2 mg FAE/100 g) significantly (p < 0.05) increased during mixing, fermenting, and baking (65% to 68%). Bound phenolics slightly (p > 0.05) decreased after 30 min fermentation (7% to 9%) compared to the dough after mixing, but increased significantly (p < 0.05) during 65 min fermenting and baking (16% to 27%). Their antioxidant activities followed a similar trend as observed for total phenolic content. The bread crust demonstrated increased free (103% to 109%) but decreased bound (2% to 3%) phenolic content, whereas bread crumb exhibited a reversal of these results. Total anthocyanin content (TAC) significantly (p < 0.05) decreased by 21% after mixing; however, it gradually increased to 90% of the original levels after fermenting. Baking significantly (p < 0.05) decreased TAC by 55%, resulting in the lowest value for bread crust (0.8 to 4.4 mg cyn-3-glu equiv./100 g). p-Hydroxybenzoic, vanillic, p-coumaric, and ferulic acids were detected in free-phenolic extracts, while protocatechuic, caffeic syringic, and sinapic were additional acids in bound-phenolic extracts. Cyanidin-3-glucoside was the detectable anthocyanin in purple wheat. Bread-making significantly (p < 0.05) increased the phenolic content and antioxidant activities; however, it compromised the anthocyanin content of purple wheat bread.
Lean Body Mass Associated with Upper Body Strength in Healthy Older Adults While Higher Body Fat Limits Lower Extremity Performance and Endurance
Authors: Charlton Karen , Batterham Marijka , Langford Kelly , Lateo Jenna , Brock Erin , Walton Karen , Lyons-Wall Philippa , Eisenhauer Katie , Green Nick , McLean Cameron
Published: August 2015

Impaired strength adversely influences an older person’s ability to perform activities of daily living. A cross-sectional study of 117 independently living men and women (age = 73.4 ± 9.4 year; body mass index (BMI) = 27.6 ± 4.8 kg/m2) aimed to assess the association between body composition and: (1) upper body strength (handgrip strength, HGS); (2) lower extremity performance (timed up and go (TUG) and sit to stand test (STS)); and (3) endurance (6-minute walk (SMWT). Body composition (% fat; lean body mass (LBM)) was assessed using bioelectrical impedance. Habitual physical activity was measured using the Minnesota Leisure Time Physical Activity Questionnaire (MLTPA) and dietary macronutrient intake, assessed using 24 h recalls and 3-day food records. Regression analyses included the covariates, protein intake (g/kg), MLTPA, age and sex. For natural logarithm (Ln) of right HGS, LBM (p < 0.001) and % body fat (p < 0.005) were significant (r2 = 46.5%; p < 0.000). For left LnHGS, LBM (p < 0.000), age (p = 0.036), protein intake (p = 0.015) and LnMLTPA (p = 0.015) were significant (r2 = 0.535; p < 0.000). For SMW, % body fat, age and LnMLTPA were significant (r2 = 0.346; p < 0.000). For STS, % body fat and age were significant (r2 = 0.251; p < 0.000). LBM is a strong predictor of upper body strength while higher % body fat and lower physical activity are associated with poorer outcomes on tests of lower extremity performance.
Development of Biodegradable Polycation-Based Inhalable Dry Gene Powders by Spray Freeze Drying
Authors: Okuda Tomoyuki , Suzuki Yumiko , Kobayashi Yuko , Ishii Takehiko , Uchida Satoshi , Itaka Keiji , Kataoka Kazunori , Okamoto Hirokazu
Published: August 2015

In this study, two types of biodegradable polycation (PAsp(DET) homopolymer and PEG-PAsp(DET) copolymer) were applied as vectors for inhalable dry gene powders prepared by spray freeze drying (SFD). The prepared dry gene powders had spherical and porous structures with a 5~10-μm diameter, and the integrity of plasmid DNA could be maintained during powder production. Furthermore, it was clarified that PEG-PAsp(DET)-based dry gene powder could more sufficiently maintain both the physicochemical properties and in vitro gene transfection efficiencies of polyplexes reconstituted after powder production than PAsp(DET)-based dry gene powder. From an in vitro inhalation study using an Andersen cascade impactor, it was demonstrated that the addition of l-leucine could markedly improve the inhalation performance of dry powders prepared by SFD. Following pulmonary delivery to mice, both PAsp(DET)- and PEG-PAsp(DET)-based dry gene powders could achieve higher gene transfection efficiencies in the lungs compared with a chitosan-based dry gene powder previously reported by us.
Photonic Nanostructures Design and Optimization for Solar Cell Application
Authors: Liu Qian , Sandgren Eric , Barnhart Miles , Zhu Rui , Huang Guoliang
Published: August 2015

In this paper, a semiconducting photonic nanostructure capable of wide range absorption and tunable optical resonance has been designed with a proposed theoretical optimization model. The design consists of ZnO/CdS core-shell nanowire arrays as well as multilayer thin films that act to absorb incident electromagnetic (EM) waves over a broad frequency range. Theoretical, as well as numerical, studies of the nanostructure inside a solar cell plate have been conducted in order to validate the proposed microstructural design. Excellent energy absorption rates of EM waves have been achieved in the high frequency range by using the optical resonance of the nanowire array. By combining multilayer thin film with the core-shell nanowire in the unit cell of a photonic solar cell, a broadband high absorption has been achieved. Moreover, the geometry of the proposed photonic nanostructure is obtained through the implementation of a genetic algorithm. This avoids local minima and an optimized absorption rate of ~90% over the frequency range of 300 to 750 THz has been obtained in the solar cell.
Assessing Rare Metal Availability Challenges for Solar Energy Technologies
Authors: Grandell Leena , Höök Mikael
Published: August 2015

Solar energy is commonly seen as a future energy source with significant potential. Ruthenium, gallium, indium and several other rare elements are common and vital components of many solar energy technologies, including dye-sensitized solar cells, CIGS cells and various artificial photosynthesis approaches. This study surveys solar energy technologies and their reliance on rare metals such as indium, gallium, and ruthenium. Several of these rare materials do not occur as primary ores, and are found as byproducts associated with primary base metal ores. This will have an impact on future production trends and the availability for various applications. In addition, the geological reserves of many vital metals are scarce and severely limit the potential of certain solar energy technologies. It is the conclusion of this study that certain solar energy concepts are unrealistic in terms of achieving TW scales.
A Practical Approach to Screening Potential Environmental Hotspots of Different Impact Categories in Supply Chains
Authors: Nakatani Jun , Maruyama Tamon , Fukuchi Kosuke , Moriguchi Yuichi
Published: August 2015

Identification of environmental hotspots becomes a pressing issue for companies pursuing sustainable supply chain management. In particular, excessive dependence on water resources outside the country may put the supply chain at unanticipated risk of water shortage. This article presents a practical approach to screening potential environmental hotspots of different impact categories that occur in the supply chain using environmental input-output analysis. First, the amounts of domestic and foreign potential impacts of global warming, terrestrial acidification, and water resource consumption, induced through supply chains were calculated for 403 sectors of Japanese products. Thereafter, with a focus on potential impacts induced through the import of raw materials, a framework for screening foreign potential hotspots was presented. The results showed that the sectoral potential impacts of water resource consumption had high rates of foreign impacts at deeper tiers of the supply chains for some sectors, which indicated that there exist hidden water hotspots outside the country. In the case study of fiber yarns, impacts on water resource consumption induced as a result of the import of crops, as well as that induced in silviculture as a result of the import of wood chips, were found to be the foreign potential hotspots.
Enantioselective Organocatalyzed Synthesis of 2-Amino-3-cyano-4H-chromene Derivatives
Authors: Sonsona Isaac , Marqués-López Eugenia , Herrera Raquel
Published: August 2015

The structural motif that results from the fusion of a benzene ring to a heterocyclic pyran ring, known as chromene, is broadly found in nature and it has been reported to be associated with a wide range of biological activity. Moreover, asymmetric organocatalysis is a discipline in expansion that is already recognized as a well-established tool for obtaining enantiomerically enriched compounds. This review covers the particular case of the asymmetric synthesis of 2-amino-3-cyano-4H-chromenes using organocatalysis. Herein, we show the most illustrative examples of the methods developed by diverse research groups, following a classification based on these five different approaches: (1) addition of naphthol compounds to substituted α,α-dicyanoolefins; (2) addition of malononitrile to substituted o-vinylphenols; (3) addition of malononitrile to N-protected o-iminophenols; (4) Michael addition of nucleophiles to 2-iminochromene derivatives; and (5) organocatalyzed formal [4+2] cycloaddition reaction. In most cases, chiral thioureas have been found to be effective catalysts to promote the synthetic processes, and generally a bifunctional mode of action has been envisioned for them. In addition, squaramides and cinchona derivatives have been occasionally used as suitable catalysts for the substrates activation.
Monoclonal Antibodies that Inhibit the Proteolytic Activity of Botulinum Neurotoxin Serotype/B
Authors: Fan Yongfeng , Dong Jianbo , Lou Jianlong , Wen Weihua , Conrad Fraser , Geren Isin , Garcia-Rodriguez Consuelo , Smith Theresa , Smith Leonard , Ho Mengfei , Pires-Alves Melissa , Wilson Brenda , Marks James
Published: August 2015

Existing antibodies (Abs) used to treat botulism cannot enter the cytosol of neurons and bind to botulinum neurotoxin (BoNT) at its site of action, and thus cannot reverse paralysis. However, Abs targeting the proteolytic domain of the toxin could inhibit the proteolytic activity of the toxin intracellularly and potentially reverse intoxication, if they could be delivered intracellularly. As such, antibodies that neutralize toxin activity could serve as potent inhibitory cargos for therapeutic antitoxins against botulism. BoNT serotype B (BoNT/B) contains a zinc endopeptidase light chain (LC) domain that cleaves synaoptobrevin-2, a SNARE protein responsible for vesicle fusion and acetylcholine vesicle release. To generate monoclonal Abs (mAbs) that could reverse paralysis, we targeted the protease domain for Ab generation. Single-chain variable fragment (scFv) libraries from immunized mice or humans were displayed on yeast, and 19 unique BoNT/B LC-specific mAbs isolated by fluorescence-activated cell sorting (FACS). The equilibrium dissociation constants (KD) of these mAbs for BoNT/B LC ranged from 0.24 nM to 14.3 nM (mean KD 3.27 nM). Eleven mAbs inhibited BoNT/B LC proteolytic activity. The fine epitopes of selected mAbs were identified by alanine-scanning mutagenesis, revealing that inhibitory mAbs bound near the active site, substrate-binding site or the extended substrate-binding site. The results provide mAbs that could prove useful for intracellular reversal of paralysis and identify epitopes that could be targeted by small molecules inhibitors.
Trends in Abundance and the Influence of Bioclimatic Factors on Westslope Cutthroat Trout in Idaho
Authors: Kennedy Patrick , Meyer Kevin A.
Published: August 2015

Westslope cutthroat trout Oncorhynchus clarkii lewisi is arguably the most widely distributed subspecies of cutthroat trout in western North America, but there has been a general lack of information on the species’ trends in abundance across the landscape. We estimated westslope cutthroat trout population growth rates using 17 data sets (including data from screw traps, daytime snorkeling, and angler creel) averaging 19 y of record that indexed abundance across Idaho. We also examined several bioclimatic indices to help understand what factors might be influencing trout abundance. Lastly, we evaluated observation error in the data sets, which is important because high observation error leads to spuriously inflated error bounds around estimates of population growth rates, reducing the ability to detect changes in population growth. Trend data showed that abundance for westslope cutthroat trout was increasing for 10 data sets, declining for 2 data sets, and stable for 5 data sets (where the confidence intervals spanned zero). Bioclimatic indices generally explained a low amount of variation in westslope cutthroat trout abundance through time, but abundance of Chinook salmon Oncorhynchus tshawytscha was significantly related to trend most often; however, the influence of Chinook salmon on westslope cutthroat trout abundance was equally likely to be positive or negative. Most (58%) data sets were estimated to have zero or minimal observation error; high observation error was most prevalent in screw-trap data sets. The results of our study suggest that most westslope cutthroat trout populations in Idaho are currently stable or increasing in abundance, but the factors affecting population trends are poorly understood.
Game Theory-Based Coverage Optimization for Small Cell Networks
Authors: Zhou Yiqing , Huang Liang , Tian Lin , Shi Jinglin
Published: August 2015

Focusing on the coverage optimization of small cell networks (SCN), this chapter starts with a detailed analysis on various coverage problems, based on which the coverage optimization problem is formulated. Then centralized and distributed coverage optimization methods based on game theory are described. Firstly, considering the coverage optimization with a control center, a modified particle swarm optimization (MPSO) is presented for the self-optimization of SCN, which employs a heuristic power control scheme to search for the global optimum solution. Secondly, distributed optimization using game theory (DGT) without a control center is concerned. Considering both throughput and interference, a utility function is formulated. Then a power control scheme is proposed to find the Nash Equilibrium (NE). Simulation results show that MPSO and DGT significantly outperform conventional schemes. Moreover, compared with MPSO, DGT uses much less overhead. Finally, further research directions are discussed and conclusions are drawn.
Resource Allocation for Device-to-Device Communications in LTE-A Network
Authors: Xu Shaoyi , Xia Chunmei
Published: August 2015

In the Long Term Evolution-Advanced (LTE-A) system, Device-to-device (D2D) communication underlying cellular networks can bring some advantages such as high data rates, low delay, low power consumption by reusing frequency bands with cellular user equipments (UEs). While at the same time, inter-cell and intra-cell interference is inevitable. The D2D users and cellular UEs will compete or cooperate to coordinate interference and share resources which incurs game theory an effective mathematical tool. This chapter proposed a Stackelberg game based algorithm to jointly allocate power and resources when the uplink frequency is shared with LTE-A users. In the game, the evolved NodeB (eNB) and D2D UEs are grouped to form the seller-buyer pair and the eNB sets prices to reduce the interference that it suffers meanwhile maximizes its revenue. For given specified prices, the D2D users compete for the resources to communicate with each other and reach their individual utility maximization. Simulation results prove that satisfying performance can be achieved by using the proposed mechanisms.
Auction-Based Resource Management in Multi-Cell OFDMA Networks
Authors: Alavi Seyed Mohamad , Zhou Chi
Published: August 2015

This chapter addresses the complex scenario of multi cell OFDMA network resource allocation and interference control by auction theory. An auction framework that meets the properties of efficiency and incentive compatibility is proposed. We consider a multi-cell OFDMA network with Fractional Frequency Reuse (FFR) implementation. An auction is presented to allocate subcarriers. According to the proposed auction framework, users will avoid bidding for the subcarriers where they have a relatively low chance of winning. Optimal bidding strategy based on Bayesian Nash Equilibrium (BNE) is obtained in which users are maximizing their net profit. A focal distance which classifies the users into cell-center and cell-edge users is characterized. The proposed approach maximizes the total auctioneer revenue, while balancing a tradeoff between system performance in terms of total system throughput and quality of service provisioning for cell-edge users.
Game Theoretic Infrastructure Sharing in Wireless Cellular Networks
Authors: Bousia Alexandra , Kartsakli Elli , Antonopoulos Angelos , Alonso Luis , Verikoukis Christos
Published: August 2015

The emerging traffic demand has fueled the rapid densification of cellular networks. The increased number of Base Stations (BSs) leads to augmented energy consumption and expenditures for the Mobile Network Operators (MNOs), especially during low traffic, when many of the BSs remain underutilized. Hence, the MNOs are encouraged to provide “green” and cost effective solutions for their networks. In this chapter, an innovative algorithm for infrastructure sharing in two-operator environments is proposed, based on BSs switching off during low traffic periods. Motivated by the conflicting interests of the operators, the problem is formulated in a game theoretic framework that enables the MNOs to act individually to estimate the switching off probabilities that reduce their financial cost. The authors analytically and experimentally estimate the potential energy and cost savings that can be accomplished. The obtained results show a significant reduction in both energy consumption and expenditures, thus giving the operators the necessary incentives for infrastructure sharing.
Broadband Antennas
Authors: Zhang Zhiya , Ur-Rehman Masood , Yang Xiaodong , Serpedin Erchin , Ren Aifeng , Zuo Shaoli , Rahman Atiqur , Abbasi Qammer Hussain
Published: August 2015

Apart from the sleeve monopole, this chapter discusses other broadband antennas as well, and the performance evaluation in terms of various measured and simulated parameters is also illustrated. This chapter will help antenna engineers get a better understanding of the antennas discussed and make a comparison with other broadband antennas. The broadband antennas that have been discussed in this chapter include: Low-profile sleeve monopole antenna, Dual-sleeve monopole antenna, Disc-conical sleeve monopole antenna, Wideband with dumbbell-shaped open sleeve antenna, Wideband unidirectional patch antenna with G-shaped strip feed, Wideband folded bowtie antenna with G-shaped strip feed and tuning stubs, Wideband bowtie antenna with inverted L-shaped coupling feed and tuning stubs.
Bandwidth Efficient Relay Transmission Strategy for MIMO-OFDMA Multicellular Networks: Relay Transmission in OFDMA Networks
Authors: Anadiotis Angelos - Christos , Gkonis Panagiotis , Kaklamani Dimitra I. , Venieris Iakovos S.
Published: August 2015

A bandwidth efficient relay transmission strategy is proposed and analyzed for MIMO – OFDMA cellular networks. Unlike other relay approaches studied in the literature, requested content plays a key role in the relay node selection procedure. The overall systems' architecture, including relaying selection procedures, data forwarding and reception is described, while privacy and security issues are analyzed as well. In the final section of the manuscript, performance metrics are provided demonstrating the superiority of the described approach compared to the non-content aware case.
Energy-Efficient Power Allocation for HARQ Systems
Authors: Chaitanya Tumula V. K. , Le-Ngoc Tho , Larsson Erik G.
Published: August 2015

Reliability of data transmission is a fundamental problem in wireless communications. Fading in wireless channels causes the signal strength to vary at the receiver and this results in loss of data packets. To improve the reliability, automatic repeat request (ARQ) schemes were introduced. However these ARQ schemes suffer from a reduction in the throughput. To address the throughput reduction, conventional ARQ schemes were combined with forward error correction (FEC) schemes to develop hybrid-ARQ (HARQ) schemes. For improving the reliability of data transmission, HARQ schemes are included in the wireless standards like LTE, LTE-Advanced and WiMAX. Conventional HARQ systems use the same transmission power in different ARQ rounds. However this is not optimal in terms of minimizing the average energy spent for successful transmission of a data packet. In this book chapter, the recent research results related to HARQ systems are reviewed first. Next, optimal resource allocation in HARQ systems with a limit on the maximum number of allowed transmissions for a data packet is considered in the next part. Specifically, the problem of minimizing the rate-outage probability under a constraint on average energy consumption per data packet for both incremental redundancy (IR)-based and Chase combining (CC)-based HARQ systems is considered. Towards solving the optimization problems, the expressions for rate-outage probability of both IR-HARQ and CC-HARQ systems in i.i.d. Rayleigh fading channels is provided. Methods to solve the optimization problems using nonlinear optimization techniques are discussed. To reduce the complexity of finding a solution, the rate-outage probability expressions are approximated, using which, the non-convex optimization problems are converted into geometric programming problems (GPPs), for which the closed-form solutions are derived. Illustrative and analytical results show that the proposed power allocation provides significant gains in energy savings over the traditional equal power allocation transmission, and the closed-form GPP solution can provide a performance close to that of the exact method for smaller values of rate-outage probability.
Hybrid Simulated-Emulated Platform – HySEP
Authors: Bisio Igor , Delucchi Stefano , Lavagetto Fabio , Marchese Mario , Portomauro Giancarlo , Zappatore Sandro
Published: August 2015

The main contribution of this chapter is the description of HySEP, Hybrid Simulated-Emulated Platform, developed by the authors and aimed at simulating/emulating heterogeneous networks to validate and test algorithms for traffic control and Quality of Service (QoS) assurance. Main features of HySEP are the appropriate level of accuracy and detail reached by using equipments available in most communication research laboratories, at low cost, and the easy configurability. HySEP is divided into three parts connected each others: the emulated core network; the simulated wireless access network communicating with the core network; and the real remote host. The overall platform is able to handle real traffic flows and overcomes the limitations introduced by other network simulators. HySEP is characterized by remarkable versatility and wide applicability to support the validation of different algorithms.
Advanced Approaches to Diagnose and Treat the Chronic Autoimmune Disorders
Authors: Sołtysiński Tomasz
Published: August 2015

Pathology and dynamics of particular cells and the molecular components of immune system is still challenging to be traced within living organisms. The techniques of molecular imaging (MI) are promising tools to monitor the immune system at work, to improve or allow personalized diagnostics and treatment, especially of the autoimmune diseases. In this study some possible targets for MI and biosensing are discussed. The personalized medicine, in addition to bioinformatics-based systemic approach, requires extensive research and novel high-throughput technologies like next generation of imaging, biosensing experimental systems based on microfluidics, nanotechnology, femtochemistry, superresolution (STED, STORM, PALM, SOFI, etc.), label-free imaging, spectroscopy (including TCSPC), MRI, multimodal optical methods, accoustic imaging through ultrasonic waves, nuclear medicine methods like SPECT and PET. Moreover, dedicated designs of modular Lab-on-Chip solutions are of high demand to perform multipurpose cell measurement and give a possibility to flexibly interact with sensed objects.
Isocenter Verification in Radiotherapy Clinical Practice Using Virtual Simulation
Authors: Matsopoulos George K. , Asvestas Pantelis A. , Markaki Vasiliki , Platoni Kalliopi , Kouloulias Vasilios
Published: August 2015

This chapter presents an overview of the procedures that are used for the verification of the patient position during radiotherapy. Furthermore, a method for the verification of the radiotherapy isocenter prior to treatment delivery is proposed. The method is based on the alignment of two Computed Tomography (CT) scans: a scan, which is acquired for treatment planning, and an additional verification scan, which is acquired prior to the treatment delivery. The proposed method was applied to CT scans, acquired from 20 patients with abdominal tumors and 20 patients with breast/lung cancer. The results of the proposed method were compared with the ones obtained using conventional methods, indicating that the estimated isocenter displacement can be translated into patient setup error inside the treatment room.
Crack Initiation Mechanism of a Cast Hybrid MMC in Low Cycle Fatigue
Authors: Iqbal A.K.M. Asif , Arai Yoshio
Published: August 2015

The low-cycle fatigue (LCF) behavior specially the fracture initiation mechanism in a cast hybrid metal matrix composite (MMC) was investigated in this research. Conventional three point bending fatigue test was carried out on a rectangular bar smooth specimen. Factographic analysis was conducted to observe the fracture initiation site. Experimental results showed that microcracks in LCF initiated at the particle–matrix interface which was located in the hybrid clustering region. Due to continued fatigue cycling, the interface debonding occurred, created additional secondary microcracks and the microcrack coalesced with other nearby microcracks caused the final fracture.
Effect of Tool Parameters on Mechanical Properties of Friction Stir Welded Aluminum Alloy
Authors: Pedapati Srinivasa Rao , Vimalan G. , Awang Mokhtar , Rani A.M.A.
Published: August 2015

The mechanical properties of weld joints in Friction Stir Welding (FSW) are influenced by the welding parameters such as rotational speed, tool geometry and welding speed. In the present study, three different tool profiles have been used to weld the joints with three different rotational speed and two welding speeds. Full factorial experiments have been conducted using DoE. The mechanical properties of weld joint were evaluated by means of tensile tests and hardness test at room temperature. The experiment result shows that the average highest number of hardness was 40.06 HRB with square tool at a rotational speed of 2000rpm while lowest hardness was 30.84 HRB with cylindrical threaded tool at rotational speed of 1800rpm. The maximum tensile strength of the joint obtained is 265 M Pa which is close to base material strength. It is observed from experimental results that joints made by square tool yield more strength compared to other tool profiles.
Effect of Electron Beam Irradiation on Mechanical Properties of Copper (II) Oxide Added LDPE Composites Aged under Acidic Condition
Authors: Tee Tiam Ting , Bee Soo Tueen , Sin Lee Tin , Ratnam Chantara Thevy , Jogindar Singh Haraveen Kaur , Low Chong Yu
Published: August 2015

In this study, the effect of aging time duration in acidic solution and electron beam irradiation on the physical and mechanical properties of copper (II) oxide added LDPE composites haven been investigated. The tensile strength of all (3 phr and 5 phr) copper (II) oxide added LDPE composites was gradually increased with increasing of electron beam irradiation dosages from 0 kGy to 200 kGy. The electron beam irradiation could induce the formation of crosslinking networks in LDPE matrix by increasing the resistance ability of LDPE matrix towards applied straining stress. The increasing of aging time duration in acidic condition up to 4 days has marginally reduced the tensile strength of all un-irradiated and irradiated all copper (II) oxide added LDPE composites. This might be attributed to the hydrochloric acid solution could degrade and breakdown the macromolecular chains in LDPE matrix and thus further reduce the tensile strength of copper (II) oxide added LDPE composites.
Finite Element Modeling of Intermetallic Compound (IMC) Solder Joints Fracture: Part B
Authors: Ooi Eang Pang , Daud Ruslizam , Amin N.A.M. , Hong T.W. , Abdul Majid M.S. , Afendi M. , Mohamad Azizul , Ariffin Ahmad Kamal
Published: August 2015

Solder joints are exposed to drop impact, vibration loading, bending, and twisting of PCBs. Study on this matter will lead to prediction of fracture load, prevalent fracture mode, exact joint interconnect size and life of joints under brittle and fatigue failure. This paper presents a finite element modeling of intermetallic compounds solder joints failure based on displacement extrapolation method. Based on conceptual FE model of intermetallic IMC solder joints, this paper present the full model of IMC model for intermetallic Mode I and Mode II fracture prediction.
Effect of Stiffness Ratio of Piecewise-Linear Spring on the Occurrence of Subharmonic Nonlinear Vibration in Automatic Transmission Powertrain
Authors: Ryu Takahiro , Rosbi S. , Matsuzaki K. , Nakae T. , Sueoka A. , Takikawa Y. , Ooi Y.
Published: August 2015

In the torque converter, a damper with a piecewise-linear spring is used to reduce the forced vibration, and the subharmonic vibration occurs when the spring restoring torque characteristics approach the switching point. This research analyzed the effect of stiffness ratio between the neighboring piecewise-linear springs on the occurrence of the subharmonic nonlinear vibration in automatic transmission powertrain. The powertrain is modeled with multi degree-of-freedom nonlinear system as an actual vehicle. The result shows higher value of the stiffness ratio between the neighboring springs creates larger value of the subharmonic vibration.
Two Way Assessments in Measuring Vibration Exposure among Workers: A Review
Authors: Khamis Nor Kamaliana , Md Deros Baba , Ismail Faizul Rizal
Published: August 2015

To this date, there were numerous studies that investigate the prevalence of work related musculoskeletal problems related to vibration. This review paper discuss recent studies related to subjective and objective assessment among workers around the world. The two main objectives of this review are: to examine published subjective and objective assessment related to vibration among workers and to extract and comprehend the detailed process of each assessment. Thirteen relevant studies were identified and chosen from electronic databases. “Vibration”, “musculoskeletal problem”, “worker”, and “subjective and objective measures” were the keywords search terms for this review paper. Past studies demonstrated various purposes for implementing subjective and objective assessments of vibration effects among industrial and non-industrial workers. It provides better understanding for future researchers and industrial practitioners to deal with vibration issues among workers. Many mixed methodology research that combines subjective and objective assessments among the workers have been applied in the past studies. However, extensive assessment were not covered by many researchers in dealing with vibration issues. Therefore, investigation and evaluation of the vibration exposure at the workplace is necessary because these groups of workers are frequently exposed to vibration in their daily work and thus faced higher risks of vibration related health effects.
Study of Vibration Absorbers Using Epoxy Reinforced Natural Fibers
Authors: Zaman Izzuddin Bin , Manshoor Bukhari , Khalid Amir
Published: August 2015

It is well known fact that vibrations contribute to excessive wear, fatigue failure and other premature failure of machine components. Thus, various methods have been applied to control these vibrations. One of the commonly used is vibration absorber. The aim of this paper is to explore the potential of epoxy reinforced natural fibers as an alternative material for vibration absorber. Both mechanical properties and dynamic characteristic of the composites are investigated through tensile test and transmissibility test, respectively. Two types of natural fibers were selected for the study; coconut coir and pineapple leaf. The results show that the tensile modulus of composites increases with the increase of fiber content, although the strength was found decreases. This reduction indicates an ineffective stress transfer between the fiber and matrix. From the tensile test result, 20 vol% of pineapple leaf fiber was found to be the optimum fraction, in which afterward was employed for fabrication vibration absorber. Meanwhile, from the transmissibility test, it was noticed that when base excitation increases, the resonance peak and attenuation frequency were changed to the lower value. The fixed-fixed end beam with attached composite vibration absorbers showed that the resonance amplitude of the beam decreased significantly. More absorbers attached on the beam produce better result in attenuating the global structural vibration.
CFD Modelling and Validation of Newtonian and Non-Newtonian Fluids in Curved Conduits
Authors: Yousif Abdulrahman , Japper-Jaafar Azuraien
Published: August 2015

CFD modelling of drag reduction agents (also called Flow Improvers) polymer additives dissolved in a newtonian solvent (UTP tap Water) was carried out in a curved conduit, A 7 equation Reynolds stress set of equations was used to simulate this flow. The purpose of this simulation is validate experimental results that show unusual pressure drop behaviour. CFD experiments show that there is pressure build-up near the end of the curved conduit due to severe centrifugal forces produced by the fluid, confirming the validity of the experimental results.