bluuebunny/crossref_metadata_2025 huggingface dataset:
Cutting Camp with Killing: ‘Bad’ Feelings, Refusing Respectability, and Homeopathic Camp
Authors: Morrison Josh
Published: March 2018

This essay argues that Ticked-Off Trannies with Knives (dir. Israel Luna, 2010, hereafter TOTWK) uses homeopathic trans camp to re-mediate the phobic traumas that trans people face. TOTWK reworks its exploitation cinema aesthetic roots, turning traumas committed against trans people and the ‘bad’ feelings they espouse into homeopathic methods of healing trans bodies, both cinematic and material, through the practice of introjection. Building on philosophies of homeopathy and theories of body camp TOTWK explicates new modes of working through trauma that do not conform to individualistic social norms or to LGBT respectability politics, decentering medicalized, pathologized narratives of transition and trans embodiment.
A Gradient-Based Cuckoo Search Algorithm for a Reservoir-Generation Scheduling Problem
Authors: Feng Yu , Zhou Jianzhong , Mo Li , Wang Chao , Yuan Zhe , Wu Jiang
Published: March 2018

In this paper, a gradient-based cuckoo search algorithm (GCS) is proposed to solve a reservoir-scheduling problem. The classical cuckoo search (CS) is first improved by a self-adaptive solution-generation technique, together with a differential strategy for Lévy flight. This improved CS is then employed to solve the reservoir-scheduling problem, and a two-way solution-correction strategy is introduced to handle variants’ constraints. Moreover, a gradient-based search strategy is developed to improve the search speed and accuracy. Finally, the proposed GCS is used to obtain optimal schemes for cascade reservoirs in the Jinsha River, China. Results show that the mean and standard deviation of power generation obtained by GCS are much better than other methods. The converging speed of GCS is also faster. In the optimal results, the fluctuation of the water level obtained by GCS is small, indicating the proposed GCS’s effectiveness in dealing with reservoir-scheduling problems.
Innovative Silicon Microgrippers for Biomedical Applications: Design, Mechanical Simulation and Evaluation of Protein Fouling
Authors: Potrich Cristina , Lunelli Lorenzo , Bagolini Alvise , Bellutti Pierluigi , Pederzolli Cecilia , Verotti Matteo , Belfiore Nicola
Published: March 2018

The demand of miniaturized, accurate and robust micro-tools for minimally invasive surgery or in general for micro-manipulation, has grown tremendously in recent years. To meet this need, a new-concept comb-driven microgripper was designed and fabricated. Two microgripper prototypes differing for both the number of links and the number of conjugate surface flexure hinges are presented. Their design takes advantage of an innovative concept based on the pseudo-rigid body model, while the study of microgripper mechanical potentialities in different configurations is supported by finite elements’ simulations. These microgrippers, realized by the deep reactive-ion etching technology, are intended as micro-tools for tissue or cell manipulation and for minimally invasive surgery; therefore, their biocompatibility in terms of protein fouling was assessed. Serum albumin dissolved in phosphate buffer was selected to mimic the physiological environment and its adsorption on microgrippers was measured. The presented microgrippers demonstrated having great potential as biomedical tools, showing a modest propensity to adsorb proteins, independently from the protein concentration and time of incubation.
Precision for Smallholder Farmers: A Small-Scale-Tailored Variable Rate Fertilizer Application Kit
Authors: Van Loon Jelle , Speratti Alicia , Gabarra Louis , Govaerts Bram
Published: March 2018

Precision agriculture technology at the hands of smallholder farmers in the developing world is often deemed far-fetched. Low-resource farmers, however, are the most susceptible to negative changes in the environment. Providing these farmers with the right tools to mitigate adversity and to gain greater control of the production process could unlock their potential and support rural communities to meet the increasing global food demand. In this study, a real-time variable rate fertilizer application system was developed and tested as an add-on kit to conventional farm machinery. In the context of low investment costs for smallholder farmers, high user-friendliness and easy installment were the main concerns for the system to be viable. The system used nitrogen (N)-sensors to assess the plant nutrient status on the spot and subsequently adjust the amount of fertilizer deposited according to the plant’s needs. Test bench trials showed that the add-on kit performed well with basic operations, but more precision is required. Variability between N-sensors and metering systems, combined with power fluctuations, created inaccuracies in the resulting application rate. Nevertheless, this work is a stepping stone towards catalyzing the elaboration of more cutting-edge precision solutions to support small-scale farmers to become successful, high producing agro-entrepreneurs.
High Glucose-Mediated Tyrosine Nitration of PI3-Kinase: A Molecular Switch of Survival and Apoptosis in Endothelial Cells
Authors: Elshaer Sally , Lemtalsi Tahira , El-Remessy Azza
Published: March 2018

Diabetes and hyperglycemia are associated with increased retinal oxidative and nitrative stress and vascular cell death. Paradoxically, high glucose stimulates expression of survival and angiogenic growth factors. Therefore, we examined the hypothesis that high glucose-mediated tyrosine nitration causes inhibition of the survival protein PI3-kinase, and in particular, its regulatory p85 subunit in retinal endothelial cell (EC) cultures. Retinal EC were cultured in high glucose (HG, 25 mM) for 3 days or peroxynitrite (PN, 100 µM) overnight in the presence or absence of a peroxynitrite decomposition catalyst (FeTPPs, 2.5 µM), or the selective nitration inhibitor epicatechin (100 µM). Apoptosis of ECs was assessed using TUNEL assay and caspase-3 activity. Immunoprecipitation and Western blot were used to assess protein expression and tyrosine nitration of p85 subunit and its interaction with the p110 subunit. HG or PN accelerated apoptosis of retinal ECs compared to normal glucose (NG, 5 mM) controls. HG- or PN-treated cells also showed significant increases in tyrosine nitration on the p85 subunit of PI3-kinase that inhibited its association with the catalytic p110 subunit and impaired PI3-kinase/Akt kinase activity. Decomposing peroxynitrite or blocking tyrosine nitration of p85 restored the activity of PI3-kinase, and prevented apoptosis and activation of p38 MAPK. Inhibiting p38 MAPK or overexpression of the constitutively activated Myr-Akt construct prevented HG- or peroxynitrite-mediated apoptosis. In conclusion, HG impairs pro-survival signals and causes accelerated EC apoptosis, at least in part via tyrosine nitration and inhibition of PI3-kinase. Inhibitors of nitration can be used in adjuvant therapy to delay diabetic retinopathy and microvascular complication.
Characterization of Phenolic Compounds in Wine Lees
Authors: Zhijing Ye , Shavandi Amin , Harrison Roland , Bekhit Alaa El-Din
Published: March 2018

The effect of vinification techniques on phenolic compounds and antioxidant activity of wine lees are poorly understood. The present study investigated the antioxidant activity of white and red wine lees generated at early fermentation and during aging. In this study, the total phenol content (TPC), total tannin content (TTC), mean degree of polymerization (mDP), and antioxidant activities of five white and eight red wine lees samples from different vinification backgrounds were determined. The results showed that vinification techniques had a significant (p < 0.05) impact on total phenol and tannin content of the samples. White wine lees had high mDP content compared with red ones. Catechin (50–62%) and epicatechin contents were the predominant terminal units of polymeric proanthocyanidin extracted from examined samples. Epigallocatechin was the predominant extension unit of white wine lees, whereas epicatechin was the predominant compound in red wine marc. The ORAC (oxygen radical absorbance capacity) assay was strongly correlated with the DPPH (α, α-diphenyl-β-picrylhydrazyl) assay, and the results showed the strong antioxidant activities associated with red wine lees (PN > 35 mg Trolox/g FDM) (PN: Pinot noir lees; FDM: Freeze-dried Material). This study indicates that tannin is one of the major phenolic compounds available in wine lees that can be useful in human and animal health applications.
An Ensemble Based Evolutionary Approach to the Class Imbalance Problem with Applications in CBIR
Authors: Irtaza Aun , Adnan Syed , Ahmed Khawaja , Jaffar Arfan , Khan Ahmad , Javed Ali , Mahmood Muhammad
Published: March 2018

In order to lower the dependence on textual annotations for image searches, the content based image retrieval (CBIR) has become a popular topic in computer vision. A wide range of CBIR applications consider classification techniques, such as artificial neural networks (ANN), support vector machines (SVM), etc. to understand the query image content to retrieve relevant output. However, in multi-class search environments, the retrieval results are far from optimal due to overlapping semantics amongst subjects of various classes. The classification through multiple classifiers generate better results, but as the number of negative examples increases due to highly correlated semantic classes, classification bias occurs towards the negative class, hence, the combination of the classifiers become even more unstable particularly in one-against-all classification scenarios. In order to resolve this issue, a genetic algorithm (GA) based classifier comity learning (GCCL) method is presented in this paper to generate stable classifiers by combining ANN with SVMs through asymmetric and symmetric bagging. The proposed approach resolves the classification disagreement amongst different classifiers and also resolves the class imbalance problem in CBIR. Once the stable classifiers are generated, the query image is presented to the trained model to understand the underlying semantic content of the query image for association with the precise semantic class. Afterwards, the feature similarity is computed within the obtained class to generate the semantic response of the system. The experiments reveal that the proposed method outperforms various state-of-the-art methods and significantly improves the image retrieval performance.
Electromagnetic Power Harvester Using Wide-Angle and Polarization-Insensitive Metasurfaces
Authors: Zhang Xuanming , Liu Haixia , Li Long
Published: March 2018

A new wide-angle and polarization-insensitive metasurface (MS) instead of traditional antenna is built as the primary ambient energy harvester in this paper. The MS is a two-dimensional energy harvesting array that is composed of subwavelength electrical small ring resonator that is working at 2.5 GHz (LTE/WiFi). In the case of different polarization and incidence angles, we demonstrate the metasurface can achieve high harvesting efficiency of 90%. The fabricated prototype of 9 × 9 MS energy harvesting array is measured, and the experimental results validate that the proposed MS has a good performance more than 80% of energy harvesting efficiency for arbitrary polarization and wide-angle incident waves. The good agreement of the simulation with the experiment results verifies the practicability and effectiveness of the proposed MS structure, which will provide a new source of supply in wireless sensor networks (WSN).
Rock Fragmentation Characteristics by TBM Cutting and Efficiency under Bi-Lateral Confinement
Authors: Chen Yulong , Song Chenpeng
Published: March 2018

In this study, the mechanisms of rock breakage are assessed using tunnel boring machine (TBM) disc cutters under bi-axial pressure. Sequential indentation tests were conducted on granite specimens using a tri-axial testing platform. The morphology and volume of the fractured surface were measured and analyzed using a three-dimensional surface profilometer. An analysis of rock breaking growth and efficiency was performed as well. When the minor confining pressure (σ1) is constant, the results show that a larger difference in confining pressure leads to a larger volume of fractured surface, thereafter improving the rock-breaking efficiency even though the penetration energy is enlarged. On the other hand, when the major confining pressure (σ2) is constant, the penetration energy increases proportionally with the σ1; however, the volume of fractured surface is decreased, and the breaking efficiency is attenuated as well.
Assist-as-Needed Control of a Robotic Orthosis Actuated by Pneumatic Artificial Muscle for Gait Rehabilitation
Authors: Dao Quy-Thinh , Yamamoto Shin-ichiroh
Published: March 2018

Rehabilitation robots are designed to help patients improve their recovery from injury by supporting them to perform repetitive and systematic training sessions. These robots are not only able to guide the subjects’ lower-limb to a designate trajectory, but also estimate their disability and adapt the compliance accordingly. In this research, a new control strategy for a high compliant lower-limb rehabilitation orthosis system named AIRGAIT is developed. The AIRGAIT orthosis is powered by pneumatic artificial muscle actuators. The trajectory tracking controller based on a modified computed torque control which employs a fractional derivative is proposed for the tracking purpose. In addition, a new method is proposed for compliance control of the robotic orthosis which results in the successful implementation of the assist-as-needed training strategy. Finally, various subject-based experiments are carried out to verify the effectiveness of the developed control system.
Review of Stratum Corneum Impedance Measurement in Non-Invasive Penetration Application
Authors: Lu Fei , Wang Chenshuo , Zhao Rongjian , Du Lidong , Fang Zhen , Guo Xiuhua , Zhao Zhan
Published: March 2018

Due to advances in telemedicine, mobile medical care, wearable health monitoring, and electronic skin, great efforts have been directed to non-invasive monitoring and treatment of disease. These processes generally involve disease detection from interstitial fluid (ISF) instead of blood, and transdermal drug delivery. However, the quantitative extraction of ISF and the level of drug absorption are greatly affected by the individual’s skin permeability, which is closely related to the properties of the stratum corneum (SC). Therefore, measurement of SC impedance has been proposed as an appropriate way for assessing individual skin differences. In order to figure out the current status and research direction of human SC impedance detection, investigations regarding skin impedance measurement have been reviewed in this paper. Future directions are concluded after a review of impedance models, electrodes, measurement methods and systems, and their applications in treatment. It is believed that a well-matched skin impedance model and measurement method will be established for clinical and point-of care applications in the near future.
Enhanced Sensitivity to Subphonemic Segments in Dyslexia: A New Instance of Allophonic Perception
Authors: Serniclaes Willy , Seck M’ballo
Published: March 2018

Although dyslexia can be individuated in many different ways, it has only three discernable sources: a visual deficit that affects the perception of letters, a phonological deficit that affects the perception of speech sounds, and an audio-visual deficit that disturbs the association of letters with speech sounds. However, the very nature of each of these core deficits remains debatable. The phonological deficit in dyslexia, which is generally attributed to a deficit of phonological awareness, might result from a specific mode of speech perception characterized by the use of allophonic (i.e., subphonemic) units. Here we will summarize the available evidence and present new data in support of the “allophonic theory” of dyslexia. Previous studies have shown that the dyslexia deficit in the categorical perception of phonemic features (e.g., the voicing contrast between /t/ and /d/) is due to the enhanced sensitivity to allophonic features (e.g., the difference between two variants of /d/). Another consequence of allophonic perception is that it should also give rise to an enhanced sensitivity to allophonic segments, such as those that take place within a consonant cluster. This latter prediction is validated by the data presented in this paper.
A New Mn–Salen Micellar Nanoreactor for Enantioselective Epoxidation of Alkenes in Water
Authors: Ballistreri Francesco , Toscano Rosa , Amato Maria , Pappalardo Andrea , Gangemi Chiara , Spidalieri Sofia , Puglisi Roberta , Trusso Sfrazzetto Giuseppe
Published: March 2018

A new chiral Mn–salen catalyst, functionalized with a long aliphatic chain and a choline group, able to act as surfactant catalyst for green epoxidation in water, is here described. This catalyst was employed with a commercial surfactant (CTABr) leading to a nanoreactor for the enantioselective epoxidation of some selected alkenes in water, using NaClO as oxidant. This is the first example of a nanoreactor for enantioselective epoxidation of non-functionalized alkenes in water.
Junctional Adhesion Molecules (JAMs): The JAM-Integrin Connection
Authors: Kummer Daniel , Ebnet Klaus
Published: March 2018

Junctional adhesion molecules (JAMs) are cell surface adhesion receptors of the immunoglobulin superfamily. JAMs are involved in a variety of biological processes both in the adult organism but also during development. These include processes such as inflammation, angiogenesis, hemostasis, or epithelial barrier formation, but also developmental processes such as hematopoiesis, germ cell development, and development of the nervous system. Several of these functions of JAMs depend on a physical and functional interaction with integrins. The JAM – integrin interactions in trans regulate cell-cell adhesion, their interactions in cis regulate signaling processes originating at the cell surface. The JAM – integrin interaction can regulate the function of the JAM as well as the function of the integrin. Beyond the physical interaction with integrins, JAMs can regulate integrin function through intracellular signaling indicating an additional level of JAM – integrin cross-talk. In this review, we describe the various levels of the functional interplay between JAMs and integrins and the role of this interplay during different physiological processes.
Morphological Characteristics of Au Films Deposited on Ti: A Combined SEM-AFM Study
Authors: Ruffino Francesco , Grimaldi Maria
Published: March 2018

Deposited Au films and coatings are, nowadays, routinely used as active or passive elements in several innovative electronic, optoelectronic, sensing, and energy devices. In these devices, the physical properties of the Au films are strongly determined by the films nanoscale structure. In addition, in these devices, often, a layer of Ti is employed to promote adhesion and, so, influencing the nanoscale structure of the deposited Au film. In this work, we present experimental analysis on the nanoscale cross-section and surface morphology of Au films deposited on Ti. In particular, we sputter-deposited thick (>100 nm thickness) Au films on Ti foils and we used Scanning Electron Microscopy to analyze the films cross-sectional and surface morphology as a function of the Au film thickness and deposition angle. In addition, we analyzed the Au films surface morphology by Atomic Force Microscopy which allowed quantifying the films surface roughness versus the film thickness and deposition angle. The results establish a relation between the Au films cross-sectional and surface morphologies and surface roughness to the film thickness and deposition angle. These results allow setting a general working framework to obtain Au films on Ti with specific morphological and topographic properties for desired applications in which the Ti adhesion layer is needed for Au.
Application of Bio-Based Wrinkled Surfaces as Cell Culture Scaffolds
Authors: Izawa Hironori , Okuda Noriko , Yonemura Tomoe , Kuroda Kohei , Ochi Kosuke , Ifuku Shinsuke , Morimoto Minoru , Saimoto Hiroyuki , Noda Mayuko , Azuma Kazuo , Okamoto Yoshiharu , Ito Norihiko
Published: March 2018

Microscopic surface architectures that can be easily manufactured have been in demand as mechano-structural cues for tissue engineering. Microscopic surface reliefs synthesized by wrinkling were expected as cell culture scaffolds for cell proliferation, control of cellular alignment and differentiation, and spheroid generation. We previously developed bio-based wrinkled films prepared via lignification-mimetic reactions and drying. Although these films are expected as a candidate for cell culture scaffolds, stability and morphology of the wrinkled surfaces in aqueous buffer solutions were not explored. Here, we investigate the surface morphologies of the wrinkled films in phosphate-buffered saline, and their application to 3T3 cell culture. The wrinkled film prepared with the immersion treatment at 40 °C maintained its wrinkled structure in phosphate-buffered saline even after five days, although the wrinkles were broadened by hydration of the skin layer. Interestingly, higher cell numbers were observed in the 3T3 cell culture using the wrinkled film than using flat film with the same surface composition. In addition, the high biocompatibility of the wrinkled film was confirmed by in vivo experiments. These results strongly encourage application of the wrinkled film as a mechano-structural cue. Studies of the advanced applications for the wrinkled films are now in progress.
Battery Modelling and Simulation Using a Programmable Testing Equipment
Authors: Vergori Elena , Mocera Francesco , Somà Aurelio
Published: March 2018

In this paper, the study and modelling of a lithium-ion battery cell is presented. To test the considered cell, a battery testing system was built using two programmable power units: an electronic load and a power supply. To communicate with them, a software/hardware interface was implemented within the National Instruments (NI) LabVIEW environment. This dedicated laboratory equipment can be used to apply charging/discharging cycles according to user defined load profiles. The battery modelling and the parameters identification procedure are described. The model was used to estimate the State Of Charge (SOC) under dynamic loading conditions. The most spread techniques used in the field of battery modelling and SOC estimation are implemented and compared.
A Royal Road to Quantum Theory (or Thereabouts)
Authors: Wilce Alexander
Published: March 2018

This paper fails to derive quantum mechanics from a few simple postulates. However, it gets very close, and does so without much exertion. More precisely, I obtain a representation of finite-dimensional probabilistic systems in terms of Euclidean Jordan algebras, in a strikingly easy way, from simple assumptions. This provides a framework within which real, complex and quaternionic QM can play happily together and allows some (but not too much) room for more exotic alternatives. (This is a leisurely summary, based on recent lectures, of material from the papers arXiv:1206:2897 and arXiv:1507.06278, the latter joint work with Howard Barnum and Matthew Graydon. Some further ideas are also explored, developing the connection between conjugate systems and the possibility of forming stable measurement records and making connections between this approach and the categorical approach to quantum theory.)
Data-Driven Jump Detection Thresholds for Application in Jump Regressions
Authors: Davies Robert , Tauchen George
Published: March 2018

This paper develops a method to select the threshold in threshold-based jump detection methods. The method is motivated by an analysis of threshold-based jump detection methods in the context of jump-diffusion models. We show that over the range of sampling frequencies a researcher is most likely to encounter that the usual in-fill asymptotics provide a poor guide for selecting the jump threshold. Because of this we develop a sample-based method. Our method estimates the number of jumps over a grid of thresholds and selects the optimal threshold at what we term the ‘take-off’ point in the estimated number of jumps. We show that this method consistently estimates the jumps and their indices as the sampling interval goes to zero. In several Monte Carlo studies we evaluate the performance of our method based on its ability to accurately locate jumps and its ability to distinguish between true jumps and large diffusive moves. In one of these Monte Carlo studies we evaluate the performance of our method in a jump regression context. Finally, we apply our method in two empirical studies. In one we estimate the number of jumps and report the jump threshold our method selects for three commonly used market indices. In the other empirical application we perform a series of jump regressions using our method to select the jump threshold.
Identifying Sustainability and Knowledge Gaps in Socio-Economic Pathways Vis-à-Vis the Sustainable Development Goals
Authors: Zimm Caroline , Sperling Frank , Busch Sebastian
Published: March 2018

With the Sustainable Development Goals (SDGs), the global community has set itself an ambitious development agenda. Current analytical and quantitative modeling capabilities fall short of being able to capture all 17 SDGs and their targets. Even highly ambitious and optimistic pathways currently used in research, such as SSP1/SSP1-2.6, do not meet all SDGs (sustainability gaps) and fail to provide information on some of them (knowledge gaps). We show that for research and modeling purposes, the SDG targets can serve as a basis but need to be operationalized to reduce complexity and also to account for long-term sustainability concerns beyond 2030. We have explored here the requirements for assessing more comprehensively the sustainability of development pathways, guided by holistic interpretation of the SDGs to enable an assessment of the potential embedded synergies and trade-offs between the economic, social and environmental objectives. We see this as call for action for science to work on filling these gaps. At the same time, this is also a call for policy makers and the global community to close the sustainability gaps that emerge from such analysis. We anticipate that such analysis will provide useful information for policy advice and investment decisions during implementation of the UN 2030 Agenda.
Dynamics of the Community of Inquiry (CoI) within a Massive Open Online Course (MOOC) for In-Service Teachers in Environmental Education
Authors: Kaul Maya , Aksela Maija , Wu Xiaomeng
Published: March 2018

One of the greatest ways to transform education systems is to develop community-centered professional supports for in-service teachers. Given the rise of distance learning platforms such as massive open online courses (MOOCs), there is a growing potential to deliver such supports at scale. The community of inquiry (CoI) framework models the asynchronous, text-based communication that defines educational experiences within such collaborative learning environments; however, methods of CoI transcript analysis must be improved. This paper uses the University of Helsinki’s 2016 MOOC, Sustainable Energy in Education, as a case study on how the CoI framework can be used to characterize the educational experience of in-service teachers in distance learning environments. Using the CoI coding protocol, this paper employs a transcript analysis of the discussion forum posts on the MOOC (n = 78), and applies improved measures of reliability in order to understand the capacity of CoI transcript analysis to reliably define online learning experiences. The findings suggest that, while the CoI framework is able to characterize some elements of online learning communities, more work needs to be done to ensure the framework captures the more nuanced elements of such educational experiences, such as the effects of course design and the relative engagement of course participants.
Performance Analysis and Optimization of a Parabolic Trough Solar Power Plant in the Middle East Region
Authors: R. P. Praveen , Abdul Baseer Mohammad , Awan Ahmed , Zubair Muhammad
Published: March 2018

The Middle East is one among the areas of the world that receive high amounts of direct solar radiation. As such, the region holds a promising potential to leverage clean energy. Owing to rapid urbanization, energy demands in the region are on the rise. Along with the global push to curb undesirable outcomes such as air pollution, emissions of greenhouse gases, and climate change, an urgent need has arisen to explore and exploit the abundant renewable energy sources. This paper presents the design, performance analysis and optimization of a 100 MWe parabolic trough collector Solar Power Plant with thermal energy storage intended for use in the Middle Eastern regions. Two representative sites in the Middle East which offer an annual average direct normal irradiance (DNI) of more than 5.5 kWh/m2/day has been chosen for the analysis. The thermodynamic aspect and annual performance of the proposed plant design is also analyzed using the System Advisor Model (SAM) version 2017.9.5. Based on the analysis carried out on the initial design, annual power generated from the proposed concentrating solar power (CSP) plant design in Abu Dhabi amounts to 333.15 GWh whereas that in Aswan recorded a value of 369.26 GWh, with capacity factors of 38.1% and 42.19% respectively. The mean efficiency of the plants in Abu Dhabi and Aswan are found to be 14.35% and 14.98% respectively. The optimization of the initial plant design is also carried out by varying two main design parameters, namely the solar multiple and full load hours of thermal energy storage (TES). Based on the findings of the study, the proposed 100 MW parabolic trough collector solar power plant with thermal energy storage can contribute to the sustainable energy future of the Middle East with reduced dependency on fossil fuels.
Movement Boundary Shape of Overburden Strata and Its Influencing Factors
Authors: He Changchun , Xu Jialin , Wang Fei , Wang Feng
Published: March 2018

Strata movement boundary is not only a parameter for the prediction of overburden strata movement and deformation but also a key index of setting shafts, roadways and protective coal pillars. Based on physical and mechanical properties of rock mass, the overburden strata are divided into bedrock and unconsolidated stratum. By means of theoretical analysis, physical simulation and numerical simulation, this paper studies the movement boundary shapes of bedrock and unconsolidated stratum, builds fitting equations of movement boundary of the two, analyzes the influence of key strata (KS) on the shape of strata movement boundary, and determines the principle of setting protective coal pillars. The results show that the movement boundaries of bedrock and unconsolidated strata are located at the outside of coal mining boundary. They are concave-upward power function curves that cannot be merged into a smooth one due to their different mechanisms of movement and deformation. The movement boundary of bedrock can approximate a straight line when lithology of the overburden is relatively uniform with thin strata in different positions; the surface movement boundary extends when the overburden has thick and stiff KS that are common in deeply buried coal seam. Therefore, the width of protective coal pillar is small if the movement boundary is regarded as a straight line. According to the curve movement boundary, the protective coal pillar for the passenger roadway of Panel 31010 of Pingdingshan No.1 mine is at least 99.4 m in width, larger than the designed one, which is the actual reason for its deformation and breakage.
Multi-Objective Optimal Design of Renewable Energy Integrated CCHP System Using PICEA-g
Authors: Li Guozheng , Wang Rui , Zhang Tao , Ming Mengjun
Published: March 2018

The integration of renewable energies into combined cooling, heating, and power (CCHP) systems has become increasingly popular in recent years. However, the optimization of renewable energies integrated CCHP (RECCHP) systems (i.e., optimal component configurations) is far from being well addressed, especially in isolated mode. This study aims to fill this research gap. A multi-objective optimization model characterizing the system reliability, system cost, and environmental sustainability is constructed. In this model, the objectives include minimization of annual total cost (ATC), carbon dioxide emission (CDE), and loss of energy supply probability (LESP). The decision variables representing the configuration of the RECCHP system include the number of photovoltaic (PV) panels and wind turbines (WTs), the tilt angle of PV panels, the height of WTs, the maximum fuel consumption, and the capacity of battery and heat storage tanks (HSTs). The multi-objective model is solved by a multi-objective evolutionary algorithm, namely, the preference-inspired coevolutionary algorithm (PICEA-g), resulting in a set of Pareto optimal (trade-off) solutions. Then, a decision-making process is demonstrated, selecting a preferred solution amongst those trade-off solutions by further considering the decision-maker preferences. Furthermore, on the optimization of the RECCHP system, operational strategies (i.e., following electric load, FEL, and following thermal load, FTL) are considered, respectively. Experimental results show that the FEL and FTL strategies lead to different optimal configurations. In general, the FTL is recommended in summer and winter, while the FEL is more suitable for spring and autumn. Compared with traditional energy systems, RECCHP has better economic and environmental advantages.
A New Scheme to Improve the Performance of Artificial Intelligence Techniques for Estimating Total Organic Carbon from Well Logs
Authors: Wang Pan , Peng Suping
Published: March 2018

Total organic carbon (TOC), a critical geochemical parameter of organic shale reservoirs, can be used to evaluate the hydrocarbon potential of source rocks. However, getting TOC through core analysis of geochemical experiments is costly and time-consuming. Therefore, in this paper, a TOC prediction model was built by combining the data from a case study in the Ordos Basin, China and core analysis with artificial intelligence techniques. In the study, the data of samples were optimized based on annealing algorithm (SA) and genetic algorithm (GA), named SAGA-FCM method. Then, back propagation algorithm (BPNN), least square support vector machine (LSSVM), and least square support vector machine based on particle swarm optimization algorithm (PSO-LSSVM) were built based on the data from optimization. The results show that the intelligence model constructed based on core samples data after optimization has much better performance in both training and validation accuracy than the model constructed based on original data. In addition, R2 and MRSE in PSO-LSSVM are 0.9451 and 1.1883, respectively, which proves that models established with optimal dataset of core samples have higher accuracy. This study shows that the quality of sample data affects the prediction of the intelligence model dramatically and the PSO-LSSVM model can present the relationship between well log data and TOC; thus, PSO-LSSVM is a powerful tool to estimate TOC.
New Method to Analyse the Cement Sheath Integrity During the Volume Fracturing of Shale Gas
Authors: Fan Mingtao , Li Jun , Liu Gonghui
Published: March 2018

Accurate prediction of the hoop stress distribution of the cement sheath and its variation regularities during volume hydraulic fracturing in shale formations is of great significance for maintaining the wellbore integrity of shale gas horizontal wells. A finite element model of casing-cement sheath-formation system (CCFS) coupling between stresses and temperature was established through a staged finite element method based on the elastic anisotropy of shale. With this new model, the effects of operation parameters and formation mechanical property changes on the cement sheath hoop stress during the multi-stage hydraulic fracturing process were analyzed, and the results were compared with the conventional model. The results revealed that the increase of the temperature of the fracturing fluid could reduce the hoop stress of the cement sheath, which decreased gradually with the decreasing elastic modulus of the cement sheath, and eventually changed to compressive stress from tensile stress. The hoop tensile stress of the cement sheath increases first and then tends to decrease with the increasing internal casing pressure, the larger the local formation stress, the smaller the pore pressure and the smaller the hoop tensile stress of the cement sheath it preforms. The findings of this paper are of great guiding significance to the research of the cement sheath stress variations during volume fracturing in shale formations and to the optimization of fracturing design.
What Drives Low-Severity Fire in the Southwestern USA?
Authors: Parks Sean , Dobrowski Solomon , Panunto Matthew
Published: March 2018

Many dry conifer forests in the southwestern USA and elsewhere historically (prior to the late 1800’s) experienced fairly frequent surface fire at intervals ranging from roughly five to 30 years. Due to more than 100 years of successful fire exclusion, however, many of these forests are now denser and more homogenous, and therefore they have a greater probability of experiencing stand-replacing fire compared to prior centuries. Consequently, there is keen interest in restoring such forests to conditions that are conducive to low-severity fire. Yet, there have been no regional assessments in the southwestern USA that have specifically evaluated those factors that promote low-severity fire. Here, we defined low-severity fire using satellite imagery and evaluated the influence of several variables that potentially drive such fire; these variables characterize live fuel, topography, climate (30-year normals), and inter-annual climate variation. We found that live fuel and climate variation (i.e., year-of-fire climate) were the main factors driving low-severity fire; fuel was ~2.4 times more influential than climate variation. Low-severity fire was more likely in settings with lower levels of fuel and in years that were wetter and cooler than average. Surprisingly, the influence of topography and climatic normals was negligible. Our findings elucidate those conditions conducive to low-severity fire and provide valuable information to land managers tasked with restoring forest structures and processes in the southwestern USA and other regions dominated by dry forest types.
A Generalized Lidar-Based Model for Predicting the Merchantable Volume of Balsam Fir of Sites Located along a Bioclimatic Gradient in Quebec, Canada
Authors: Yoga Sarah , Bégin Jean , Daigle Gaétan , Riopel Martin , St-Onge Benoît
Published: March 2018

Lidar-based models rely on an optimal relationship between the field and the lidar data for accurate predictions of forest attributes. This relationship may be altered by the variability in the stand growth conditions or by the temporal discrepancy between the field inventory and the lidar survey. In this study, we used lidar data to predict the timber merchantable volume (MV) of five sites located along a bioclimatic gradient of temperature and elevation. The temporal discrepancies were up to three years. We adjusted a random canopy height coefficient (accounting for the variability amongst sites), and a growth function (accounting for the growth during the temporal discrepancy), to the predictive model. The MV could be predicted with a pseudo-R2 of 0.86 and a residual standard deviation of 24.3 m3 ha−1. The average biases between the field-measured and the predicted MVs were small. The variability of MV predictions was related to the bioclimatic gradient. Fixed-effect models that included a bioclimatic variable provided similar prediction accuracies. This study suggests that the variability amongst sites, the occurrence of a bioclimatic gradient and temporal discrepancies are essential in building a generalized lidar-based model for timber volume.
Forecasting: A New Open Access Journal Dealing with Time Series Analysis and Forecasting
Authors: Rojas Ignacio
Published: March 2018

Welcome to Forecasting, a new, online, open access journal, which provides an advanced forum for studies related to forecasting: theoretical, practical, computational and methodological.[...]
Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic Nuclei
Authors: Pasetto Alice , Carrasco-González Carlos , O’Sullivan Shane , Basu Aritra , Bruni Gabriele , Kraus Alex , Curiel Salvador , Mack Karl-Heinz
Published: March 2018

Knowing how the ambient medium in the vicinity of active galactic nuclei (AGNs) is shaped is crucial to understanding generally the evolution of such cosmic giants as well as AGN jet formation and launching. Thanks to the new broadband capability now available at the Jansky Very Large Array (JVLA), we can study changes in polarization properties, fractional polarization, and polarization angles, together with the total intensity spectra of a sample of 14 AGNs, within a frequency range from 1 to 12 GHz. Depolarization modeling has been performed by means of so-called “qu-fitting” to the polarized data, and a synchrotron self absorption model has been used for fitting to the total intensity data. We found complex behavior both in the polarization spectra and in the total intensity spectra, and several Faraday components with a large rotation measure (RM) and several synchrotron components were needed to represent these spectra. Here, results for three targets are shown. This new method of analyzing broadband polarization data through qu-fitting successfully maps the complex surroundings of unresolved objects.
Temperature-Responsive Hydrogel-Coated Gold Nanoshells
Authors: Park Hye , Srisombat La-ongnuan , Jamison Andrew , Liu Tingting , Marquez Maria , Park Hansoo , Lee Sungbae , Lee Tai-Chou , Lee T.
Published: March 2018

Gold nanoshells (~160 nm in diameter) were encapsulated within a shell of temperature-responsive poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-co-AA)) using a surface-bound rationally-designed free radical initiator in water for the development of a photothermally-induced drug-delivery system. The morphologies of the resultant hydrogel-coated nanoshells were analyzed by scanning electron microscopy (SEM), while the temperature-responsive behavior of the nanoparticles was characterized by dynamic light scattering (DLS). The diameter of the P(NIPAM-co-AA) encapsulated nanoshells decreased as the solution temperature was increased, indicating a collapse of the hydrogel layer with increasing temperatures. In addition, the optical properties of the composite nanoshells were studied by UV-visible spectroscopy. The surface plasmon resonance (SPR) peak of the hydrogel-coated nanoshells appeared at ~800 nm, which lies within the tissue-transparent range that is important for biomedical applications. Furthermore, the periphery of the particles was conjugated with the model protein avidin to modify the hydrogel-coated nanoshells with a fluorescent-tagged biotin, biotin-4-fluorescein (biotin-4-FITC), for colorimetric imaging/monitoring.
Concentrations of 2,4-Dichlorophenol and 2,5-Dichlorophenol in Urine of Korean Adults
Authors: Park Hyejin , Kim Kisok
Published: March 2018

Humans are exposed to the environmental pollutants 2,4-dichlorophenol (2,4-DCP) and 2,5-dichlorophenol (2,5-DCP) through air, the use of water and the consumption of products. In this study, we evaluated the urinary concentrations of these compounds in Korean people between the ages of 18 to 69 years, by making use of data from the Korean National Human Biomonitoring Survey that was completed in 2009. Of 1865 representative Koreans, 63.4% and 97.9% were found to have concentrations of 2,4-DCP and 2,5-DCP > 0.05 μg/L (limit of detection) in their urine, respectively. The geometric mean of urinary concentrations was 0.14 μg/L (confidence interval of 95% = 0.13–0.16) and 0.44 μg/L (confidence interval = 0.41–0.48), respectively. It was found that the adjusted proportional changes in 2,4-DCP concentrations were significantly associated with body mass index, whereas those of 2,5-DCP concentrations were influenced by place of residence. From these findings, it is evident that most adults in Korea have levels of 2,4-DCP and 2,5-DCP that are detectable in their urine and the burden of these compounds on their bodies varies depending on numerous demographic factors.
Classification Accuracy of a Wearable Activity Tracker for Assessing Sedentary Behavior and Physical Activity in 3–5-Year-Old Children
Authors: Byun Wonwoo , Lee Jung-Min , Kim Youngwon , Brusseau Timothy
Published: March 2018

This study examined the accuracy of the Fitbit activity tracker (FF) for quantifying sedentary behavior (SB) and varying intensities of physical activity (PA) in 3–5-year-old children. Twenty-eight healthy preschool-aged children (Girls: 46%, Mean age: 4.8 ± 1.0 years) wore the FF and were directly observed while performing a set of various unstructured and structured free-living activities from sedentary to vigorous intensity. The classification accuracy of the FF for measuring SB, light PA (LPA), moderate-to-vigorous PA (MVPA), and total PA (TPA) was examined calculating Pearson correlation coefficients (r), mean absolute percent error (MAPE), Cohen’s kappa (k), sensitivity (Se), specificity (Sp), and area under the receiver operating curve (ROC-AUC). The classification accuracies of the FF (ROC-AUC) were 0.92, 0.63, 0.77 and 0.92 for SB, LPA, MVPA and TPA, respectively. Similarly, values of kappa, Se, Sp and percentage of correct classification were consistently high for SB and TPA, but low for LPA and MVPA. The FF demonstrated excellent classification accuracy for assessing SB and TPA, but lower accuracy for classifying LPA and MVPA. Our findings suggest that the FF should be considered as a valid instrument for assessing time spent sedentary and overall physical activity in preschool-aged children.
Microplastic Contamination of Wild and Captive Flathead Grey Mullet (Mugil cephalus)
Authors: Cheung Lewis , Lui Ching , Fok Lincoln
Published: March 2018

A total of 60 flathead grey mullets were examined for microplastic ingestion. Thirty wild mullets were captured from the eastern coast of Hong Kong and 30 captive mullets were obtained from fish farms. Microplastic ingestion was detected in 60% of the wild mullets, with an average of 4.3 plastic items per mullet, while only 16.7% of captive mullets were found to have ingested microplastics, with an average of 0.2 items per mullet. The results suggested that wild mullets have a higher risk of microplastic ingestion than their captive counterparts. The most common plastic items were fibres that were green in colour and small in size (<2 mm). Polypropylene was the most common polymer (42%), followed by polyethylene (25%). In addition, the abundance of microplastics was positively correlated with larger body size among the mullets.