bluuebunny/crossref_metadata_2025 huggingface dataset:
MOSTLY UNKNOWN BUT STILL PROFITABLE: THE LOHN SYSTEM IN THE NORTH-EST REGION OF ROMANIA
Authors: Nichifor Bogdan , Zait Luminita
Published: January 2018

The garment manufacturing sector (and, implicitly, knitwear) was one of the most important areas of the Romanian economy during the communist era, satisfying a large part of the existing demand, both in the domestic market and at the external ones. By making a statistic untill the year of 1989, we note that this sector occupied about 10% of Romania's industrial output, 30% of the country's exports and 20% of the number of employees in industry. After 1989, this industry experienced several stages of development, but also stagnation due to the conjuncture that the Romanian economy crossed. Currently, the knitwear market in Romania is dominated by legal entities that carry out lohn production activities at the expense of own brand production, the factors favoring this reality being: relocation of lohn businesses from China to countries like: Romania, Morocco, Tunisia, Turkey, Hungary etc .; high attractiveness of the lohn production system for domestic legal entities, both from an economic perspective and from the perspective of constancy of orders; and so on. This article wishes to highlight the current situation in the knitwear sector in the Northeast Region of Romania, namely the trends from the perspective of the local legal entities working on the lohn production system.
Fretting Fatigue Cracking of an Arresting Feature in a Turbine Disk of a Heavy-Duty Gas Turbine Engine
Authors: Neidel A. , Giller M. , Riesenbeck S.
Published: January 2018

A check for surface cracks under application of the magnetic flux leakage method (MT testing) was performed on the turbine wheel disk of a heavy-duty turbine gas turbine engine for energy generation. It revealed unacceptable findings on the bearing surface of the sealing plate groove. In order to identify the damage-causing mechanism of the material, a metallographic examination was performed. The findings during non-destructive material testing were caused by a gaping material separation which was also easily detectable to the naked eye. The material separation is a high-cycle fatigue crack induced by fretting. Hence, the damage causing mechanism was fretting fatigue cracking.
Metallographic Evaluation of Selective Oxidation for the Temperature Measurement on Spark Plug Electrodes
Authors: Reinsch B. , Nufer S. , Soldera F. , Mücklich F.
Published: January 2018

The present work describes a method for the temperature measurement in furnaces or test rigs for the range 750 – 1000°C by means of the selective oxidation of nickel in palladium-gold-nickel alloys in a constant oxygen atmosphere (pO2 = 2.1 · 104 Pa). For this method, extensive aging tests using alloys of different compositions (PdAu x Ni2, x = 0; 10; 15; 20; 30 wt. %) were performed and the alloy-dependent material constants ln(A) and B of the Arrhenius equation were determined. These values allowed for the spatially resolved evaluation of the temperature load by means of a metallographic analysis of the oxidation depth. It is furthermore shown that the oxygen diffusion rate in PdAuxNi2 as well as the activation energy needed decrease with increasing gold content x, while the lattice constant a increases. In addition to that, a geometric derivation for the determination of the layer thickness is presented aiming at simplifying the preparation of the wire-shaped samples.
Differentiation of neutrophil-like HL-60 cells strongly impacts their rolling on surfaces with various adhesive properties under a pressing force
Authors: Shirai Atsushi , Sugiyama Yoshiro , Rieu Jean-Paul
Published: January 2018

BACKGROUND:

HL-60 cells have been used in in vitro experiments of neutrophils rolling. They lose uniform spherical appearance and enhance deformability by differentiation to neutrophil-like cells, which would affect their rolling characteristics.

OBJECTIVE:

We investigate the influence of differentiation and coating of target substrate on the fundamental rolling characteristics of the cells under a constant pressing force which mimics the pressing force to the vessel wall by erythrocytes in vivo.

METHODS:

Motions of undifferentiated and differentiated HL-60 cells on plain or MPC-polymer-coated flat glass substrate were compared using a homemade inclined centrifuge microscope system.

RESULTS:

Most of the cells alternated between stop and go during the motion. The differentiation resulted in a high temporal ratio of the non-moving state and low mean velocity during the moving state, together with a high suppression performance of cell adhesion by the polymer. It was also suggested that the cells were mostly rolling but that the coating probably induced an infrequent slip on the substrate to stabilize the cells motion.

CONCLUSIONS:

Differentiation strongly affects adhesivity of HL-60 cells but less affects the mean velocity. Our findings also demonstrate the importance of the pressing force and advantage of the present system with respect to classical flow chambers.
A New and Versatile Adjustable Rigidity Actuator with Add-on Locking Mechanism (ARES-XL)
Authors: Cestari Manuel , Sanz-Merodio Daniel , Garcia Elena
Published: January 2018

Adjustable compliant actuators are being designed and implemented in robotic devices because of their ability to minimize large forces due to impacts, to safely interact with the user, and to store and release energy in passive elastic elements. Conceived as a new force-controlled compliant actuator, an adjustable rigidity with embedded sensor and locking mechanism actuator (ARES-XL) is presented in this paper. This compliant system is intended to be implemented in a gait exoskeleton for children with neuro muscular diseases (NMDs) to exploit the intrinsic dynamics during locomotion. This paper describes the mechanics and initial evaluation of the ARES-XL, a novel variable impedance actuator (VIA) that allows the implementation of an add-on locking mechanism to this system, and in combination with its zero stiffness capability and large deflection range, provides this novel joint with improved properties when compared to previous prototypes developed by the authors and other state-of-the-art (SoA) devices. The evaluation of the system proves how this design exceeds the main capabilities of a previous prototype as well as providing versatile actuation that could lead to its implementation in multiple joints.
Agricultural Health and Safety Survey in Friuli Venezia Giulia
Authors: Cividino Sirio , Pergher Gianfranco , Zucchiatti Nicola , Gubiani Rino
Published: January 2018

The work in the agricultural sector has taken on a fundamental role in the last decades, due to the still too high rate of fatal injuries, workplace accidents, and dangerous occurrences reported each year. The average old age of agricultural machinery is one of the main issues at stake in Italy. Numerous safety problems stem from that; therefore, two surveys were conducted in two different periods, on current levels of work safety in agriculture in relation to agricultural machinery’s age and efficiency, and to show the levels of actual implementation of the Italian legislation on safety and health at work in the agricultural sector. The surveys were carried out, considering a sample of 161 farms located in the region Friuli Venezia Giulia (North-East of Italy). The research highlights the most significant difficulties the sample of farms considered have in enforcing the law. One hand, sanitary surveillance and workers’ information and training represent the main deficiencies and weakest points in family farms. Moreover, family farms do not generally provide the proper documentation concerning health and safety at workplaces, when they award the contract to other companies. On the other hand, lack of maintenance program for machinery and equipment, and of emergency plans and participation of workers’ health and safety representative, are the most common issues in farms with employees. Several difficulties are also evident in planning workers’ training programs. Furthermore, the company physician’s task is often limited to medical controls, so that he is not involved in risk assessment and training. Interviews in heterogeneous samples of farms have shown meaningful outcomes, which have subsequently been used to implement new databases and guidelines for Health and Safety Experts and courses in the field of Work Safety in agriculture. In conclusion, although the legislation making training courses for tractor operators and tractor inspections compulsory dates back to the years 2012 and 2015, deadlines have been prorogued, and the law is not yet fully applied, so that non-upgraded unfit old agricultural machinery is still being used by many workers, putting their health and their own lives at risk.
Measuring the Economic Impact of Farmers’ Markets on Local Economies in the Basque Country
Authors: Malagon-Zaldua Eduardo , Begiristain-Zubillaga Mirene , Onederra-Aramendi Aintzira
Published: January 2018

Farmers’ markets are a traditional exchange space for local peasants, around which alternative agri-food networks (AFNs) are being built on a local scale. These AFNs seek to establish quality and trust-based equitable relationships within value chains. The main objective of this paper is to measure the economic impact of 10 farmers’ markets on the local economy in the Basque province of Gipuzkoa (Northern Spain). To calculate the degree of impact, we use the tools of input-output analysis, adapting the SEED & NEED & FEED (Sticky Economic Evaluation Device & Neighborhood Exchange Evaluation Device & Food Environment Evaluation Device) approach to the specific context of the Basque Country. The results obtained give an economic value of the impact of these marketing spaces, including direct and indirect effects on other economic sectors. Furthermore, the results show that markets present other factors, not just economic, that add value for both producers and consumers, as well as for the local economy.
In-Depth Comparison of Lysine-Based Antibody-Drug Conjugates Prepared on Solid Support Versus in Solution
Authors: Arlotta Keith , Gandhi Aditya , Chen Hsiao-Nung , Nervig Christine , Carpenter John , Owen Shawn
Published: January 2018

Antibody drug conjugates are a rapidly growing form of targeted chemotherapeutics. As companies and researchers move to develop new antibody–drug conjugate (ADC) candidates, high-throughput methods will become increasingly common. Here we use advanced characterization techniques to assess two trastuzumab-DM1 (T-DM1) ADCs; one produced using Protein A immobilization and the other produced in solution. Following determination of payload site and distribution with liquid chromatography-mass spectrometry (LC/MS), thermal stability, heat-induced aggregation, tertiary structure, and binding affinity were characterized using differential scanning calorimetry (DSC), dynamic light scattering (DLS), Raman spectroscopy, and isothermal titration calorimetry (ITC), respectively. Small differences in the thermal stability of the CH2 domain of the antibody as well as aggregation onset temperatures were observed from DSC and DLS, respectively. However, no significant differences in secondary and tertiary structure were observed with Raman spectroscopy, or binding affinity as measured by ITC. Lysine-based ADC conjugation produces an innately heterogeneous population that can generate significant variability in the results of sensitive characterization techniques. Characterization of these ADCs indicated nominal differences in thermal stability but not in tertiary structure or binding affinity. Our results lead us to conclude that lysine-based ADCs synthesized following Protein A immobilization, common in small-scale conjugations, are highly similar to equivalent ADCs produced in larger scale, solution-based methods.
Phase Coherence Index, HHT and Wavelet Analysis to Extract Features from Active and Passive Distribution Networks
Authors: Vergura Silvano , Carpentieri Mario
Published: January 2018

The modern Power Distribution Systems (PDS) operate more and more often with distributed generators and the optimal operation of the utility distribution systems has to take into account the possibility of bi-directional energy flows, although this event may only occur for some of the PDS. For this reason, the analysis methods that are usually employed to investigate the electrical behavior of the PDS can be more or less effective, depending on the typology of electrical loads connected to the line and on the presence or absence of Renewable Energy Sources (RES). This paper proposes either a methodology to select the best performing mathematical tool to investigate the electrical behavior of the PDS—depending on their linearity and stationarity—either an index to discriminate the PDS on the basis of a different amount of PV penetration. The proposed approach is applied to three real cases of PDS with different characteristics: residential and commercial, in the presence or absence of PV plants. In addition, two indices that are able to characterize the PDS in terms of periodicity and disturbance of the electrical signal are considered, specifically the phase coherence between two arbitrary signals and the phase coherence between an arbitrary signal and a reference one. The combined use of these indices can give valuable information about the degree of non-linearity and can be a measure of the PV penetration in a distribution circuit.
A Low-Power WLAN Communication Scheme for IoT WLAN Devices Using Wake-Up Receivers
Authors: Hong Hanseul , Kim Young , Kim Ronny
Published: January 2018

In this paper, we propose a delay- and power-efficient, multi-user, low-power wireless local area network (WLAN) communication scheme for Internet of Things (IoT) WLAN devices. Extremely low-power operation is one of the key requirements of emerging IoT devices. However, the current duty-cycle-based power saving approach may incur large access delay times owing to the trade-offs between the power consumption and the access delay. In order to reduce this delay and enhance the power-saving performance, wake-up receiver-based schemes have been proposed. However, because wake-up receiver-based schemes do not consider multiuser operation in dense communication environments, large delays are inevitable in the case of multiuser operation. In order to provide extremely low-power operation and under 1-mW standby power with reduced delay, we employed the optimized multiuser transmission scheduling of IEEE 802.11ax in the proposed scheme and proper enhanced distributed channel access (EDCA) parameter settings. This is with the aim to reduce the delay caused by long wake-up times, and to avoid collisions caused by simultaneous transmission in uplink multiuser scenario. By using the proposed scheme, simultaneous IoT communication with multiple mobile IoT devices is possible while providing low-power operation. Simulation results verified the outstanding delay performance of the proposed scheme.
Real-Time Strength Monitoring for Concrete Structures Using EMI Technique Incorporating with Fuzzy Logic
Authors: Choi Sang-Ki , Tareen Najeebullah , Kim Junkyeong , Park Seunghee , Park Innjoon
Published: January 2018

This study estimates the strength of a special mixture of high-strength concrete (HSC) with admixtures for use in a nuclear power plant (NPP). Nuclear power plant structures need a HSC with some additional qualities to operate the safe options. For this purpose, the experimented concrete was specially designed to fulfill the required qualities of NPP. For gaining these desirable qualities, it needs to monitor the concrete strength development process. Here, the PZT materials were used as sensors to acquire data by measuring the electromechanical impedance (EMI), and then cross correlation (CC) was calculated to look at changes according to strength development. Data were measured for 28 days, and over this period concrete can gain up to 96% of its design strength. This technique is based on a single sensor. After casting concrete, the PZT material starts vibrating as an actuator to produce vibrations. At the same time, it also works as a sensor to measure the dynamic response of the structure to the vibrations. With strength development, the resonant frequencies of the EMI start changing. To estimate the strength development, a fuzzy logic tool was used to analyze the parameters, allowing for us to estimate and predict the concrete strength. For cross-checking, the estimated strength was compared with the actual strength of concrete; this was determined by examining cuboid cores taken from specimens during experiments at the 1st, 3rd, 7th, 14th, and 28th days. According to the results, this approach of strength estimation and monitoring the strength development is useful for forecasting the stability of structures.
“Festive Customs” and “Everyday Beauty”. The Agenda and Self-Conception of the Nordic Life Reform Movement
Authors: Seelow Atli
Published: January 2018

In the second half of the 19th century, a wave of modernization, industrialization and urbanization swept the Nordic countries, catapulting what had until then been lagging and primarily rural countries into modernity. These major upheavals, however, also plunged the Nordic countries into a profound social and cultural crisis resulting from their consciousness of their own backwardness vis-a-vis the countries on the European continent, as well as the recognition that a nostalgic nationalism recalling a mythical past had become obsolete in the industrial age. In response to this crisis, a life reform movement emerged that was based on Arts and Crafts movements as well as various artistic and literary reform movements and—equally absorbing rural traditions and progressive social ideas—tried to establish a new national everyday culture. In this article, the two key terms coined by Ellen Key, “Festive Customs” (“festvanor”) and “Everyday Beauty” (“vardagsskönhet”)—the programmatic core of the Nordic life reform movement—are analysed and illustrated in various typical manifestations. It also examines to what extent the Nordic life reform movement with these two key concepts as its core agenda found expression in arts and crafts, in painting as well as in the architecture of the late nineteenth and early twentieth century and contributed to the progress of social and cultural renewal.
Oriented Polar Molecules in a Solid Inert-Gas Matrix: A Proposed Method for Measuring the Electric Dipole Moment of the Electron
Authors: Vutha A. , Horbatsch M. , Hessels E.
Published: January 2018

We propose a very sensitive method for measuring the electric dipole moment of the electron using polar molecules embedded in a cryogenic solid matrix of inert-gas atoms. The polar molecules can be oriented in the z ^ -direction by an applied electric field, as has recently been demonstrated by Park et al. The trapped molecules are prepared into a state that has its electron spin perpendicular to z ^ , and a magnetic field along z ^ causes precession of this spin. An electron electric dipole moment d e would affect this precession due to the up to 100 GV/cm effective electric field produced by the polar molecule. The large number of polar molecules that can be embedded in a matrix, along with the expected long coherence times for the precession, allows for the possibility of measuring d e to an accuracy that surpasses current measurements by many orders of magnitude. Because the matrix can inhibit molecular rotations and lock the orientation of the polar molecules, it may not be necessary to have an electric field present during the precession. The proposed technique can be applied using a variety of polar molecules and inert gases, which, along with other experimental variables, should allow for careful study of systematic uncertainties in the measurement.
Development and Examination of Sweet Potato Flour Fortified with Indigenous Underutilized Seasonal Vegetables
Authors: Teye Ernest , Agbemafle Robert , Lamptey Francis
Published: January 2018

Developing nutrient-rich vegetable flour using locally under-utilized food crops in Africa would improve rural house-hold nutrition. This study seeks to develop nutrient-dense vegetable flour from different proportions of Sweet potato (Sp) 40–100%, Avocado pear (Avo) 10–40%, and Turkey berry (Tor) 10–40%, using completely randomized design (CRD) with 14 treatment combinations and three replications. The proximate composition, mineral composition, and functional properties were investigated on the composite flour. The results showed significant differences in all the parameters analyzed for the various composite flours. As the amount of Avo and Tor was added to the Sp, the proximate composition was enhanced except for the percentage carbohydrate, which decreased from 83.92 to 54.59 g/100 g. The mineral composition was also improved by the incorporation of Avo and Tor. Favourable functional properties were also obtained. The optimal composite flour was made up of 40% Sp, 35% Avo, and 25% Tor. The functional properties of the composite flours were better than the control (Sweet potato flour). Fortifying Sp flour with Avo and Tor is feasible and could be an easy and affordable means to improve rural nutrition, as it requires simple logistics for the ordinary rural household to produce the composite of the desired choice.
A Cuprous Oxide Thin Film Non-Enzymatic Glucose Sensor Using Differential Pulse Voltammetry and Other Voltammetry Methods and a Comparison to Different Thin Film Electrodes on the Detection of Glucose in an Alkaline Solution
Authors: Dai Yifan , Molazemhosseini Alireza , Abbasi Kevin , Liu Chung
Published: January 2018

A cuprous oxide (Cu2O) thin layer served as the base for a non-enzymatic glucose sensor in an alkaline medium, 0.1 NaOH solution, with a linear range of 50–200 mg/dL using differential pulse voltammetry (DPV) measurement. An X-ray photoelectron spectroscopy (XPS) study confirmed the formation of the cuprous oxide layer on the thin gold film sensor prototype. Quantitative detection of glucose in both phosphate-buffered saline (PBS) and undiluted human serum was carried out. Neither ascorbic acid nor uric acid, even at a relatively high concentration level (100 mg/dL in serum), interfered with the glucose detection, demonstrating the excellent selectivity of this non-enzymatic cuprous oxide thin layer-based glucose sensor. Chronoamperometry and single potential amperometric voltammetry were used to verify the measurements obtained by DPV, and the positive results validated that the detection of glucose in a 0.1 M NaOH alkaline medium by DPV measurement was effective. Nickel, platinum, and copper are commonly used metals for non-enzymatic glucose detection. The performance of these metal-based sensors for glucose detection using DPV were also evaluated. The cuprous oxide (Cu2O) thin layer-based sensor showed the best sensitivity for glucose detection among the sensors evaluated.
Recurrent Hemorrhagic Conversion of Ischemic Stroke in a Patient with Mechanical Heart Valve: A Case Report and Literature Review
Authors: Tarver Micheal , Schmidt Tyler , Koltz Michael
Published: January 2018

The authors present a unique case of recurrent stroke, discovered to be secondary to hemorrhagic conversion of microemboli from a mechanical aortic valve despite anticoagulation with Coumadin. The complexity of this case was magnified by the patient’s young age, a mechanical heart valve (MHV), and a need for anticoagulation to maintain MHV patency in a setting of potentially life-threatening intracranial hemorrhage. Anticoagulant and antiplatelet therapy are risk factors for hemorrhagic conversion post-cerebral ischemia; however, the pathophysiology underlying endothelial cell dysfunction causing red blood cell extravasation is an active area of basic and clinical research. The need for randomized clinical trials to aid in the creation of standardized treatment protocol continues to go unmet. Consequently, there is marked variation in therapeutic approaches to treating intracranial hemorrhage in patients with an MHV. Unfortunately, patients with an MHV are considered at high thromboembolic (TE) risk, and these patients are often excluded from clinical trials of acute stroke due to their increased TE potential. The authors feel this case represents an example of endothelial dysfunction secondary to microthrombotic events originating from an MHV, which caused ischemic stroke with hemorrhagic conversion complicated by the need for anticoagulation for an MHV. This case offers a definitive treatment algorithm for a complex clinical dilemma.
Dancing with Gravity—Why the Sense of Balance Is (the) Fundamental
Authors: Fuchs Dominik
Published: January 2018

The sense of balance, which is usually barely noticeable in the background of each of our movements, only becomes manifest in its function during intense stimulation or in the event of illness, which may quite literally turn your world upside down. While it is true that balance is becoming a bigger issue, that is mainly because people are losing it more frequently. So why is balance not as commonly talked about in psychology, medicine or the arts as the other five traditional senses? This is partly due to its unusual multi-modal nature, whereby three sensory inputs are coordinated and integrated by the central nervous system. Without it, however, we might not have much use for the other senses. The sense of balance encompasses the bodily experience in its entirety. Not only do we act with the body, we may also think and feel through it and with it. Bodily states are not simply effects of cognition; they cause it as well. Equilibrioception is an essential sense and it is interconnected with a wide range of other areas, including cognition, perception, embodiment, the autonomic nervous system, aesthetics, the arts, and education.
Relationships between Substrate Promiscuity and Chiral Selectivity of Esterases from Phylogenetically and Environmentally Diverse Microorganisms
Authors: Coscolín Cristina , Martínez-Martínez Mónica , Chow Jennifer , Bargiela Rafael , García-Moyano Antonio , Bjerga Gro , Bollinger Alexander , Stokke Runar , Steen Ida , Golyshina Olga , Yakimov Michail , Jaeger Karl-Erich , Yakunin Alexander , Streit Wolfgang , Golyshin Peter , Ferrer Manuel
Published: January 2018

Substrate specificity and selectivity of a biocatalyst are determined by the protein sequence and structure of its active site. Finding versatile biocatalysts acting against multiple substrates while at the same time being chiral selective is of interest for the pharmaceutical and chemical industry. However, the relationships between these two properties in natural microbial enzymes remain underexplored. Here, we performed an experimental analysis of substrate promiscuity and chiral selectivity in a set of 145 purified esterases from phylogenetically and environmentally diverse microorganisms, which were assayed against 96 diverse esters, 20 of which were enantiomers. Our results revealed a negative correlation between substrate promiscuity and chiral selectivity in the evaluated enzymes. Esterases displaying prominent substrate promiscuity and large catalytic environments are characterized by low chiral selectivity, a feature that has limited commercial value. Although a low level of substrate promiscuity does not guarantee high chiral selectivity, the probability that esterases with smaller active sites possess chiral selectivity factors of interest for industry (>25) is significantly higher than for promiscuous enzymes. Together, the present study unambiguously demonstrates that promiscuous and selective esterases appear to be rare in nature and that substrate promiscuity can be used as an indicator of the chiral selectivity level of esterases, and vice versa.
Introducing Magnetism into 2D Nonmagnetic Inorganic Layered Crystals: A Brief Review from First-Principles Aspects
Authors: Shi Xinying , Huang Zhongjia , Huttula Marko , Li Taohai , Li Suya , Wang Xiao , Luo Youhua , Zhang Meng , Cao Wei
Published: January 2018

Pioneering explorations of the two-dimensional (2D) inorganic layered crystals (ILCs) in electronics have boosted low-dimensional materials research beyond the prototypical but semi-metallic graphene. Thanks to species variety and compositional richness, ILCs are further activated as hosting matrices to reach intrinsic magnetism due to their semiconductive natures. Herein, we briefly review the latest progresses of manipulation strategies that introduce magnetism into the nonmagnetic 2D and quasi-2D ILCs from the first-principles computational perspectives. The matrices are concerned within naturally occurring species such as MoS2, MoSe2, WS2, BN, and synthetic monolayers such as ZnO and g-C2N. Greater attention is spent on nondestructive routes through magnetic dopant adsorption; defect engineering; and a combination of doping-absorbing methods. Along with structural stability and electric uniqueness from hosts, tailored magnetic properties are successfully introduced to low-dimensional ILCs. Different from the three-dimensional (3D) bulk or zero-dimensional (0D) cluster cases, origins of magnetism in the 2D space move past most conventional physical models. Besides magnetic interactions, geometric symmetry contributes a non-negligible impact on the magnetic properties of ILCs, and surprisingly leads to broken symmetry for magnetism. At the end of the review, we also propose possible combination routes to create 2D ILC magnetic semiconductors, tentative theoretical models based on topology for mechanical interpretations, and next-step first-principles research within the domain.
Determination of In-Situ Stress and Geomechanical Properties from Borehole Deformation
Authors: Han Hong , Yin Shunde
Published: January 2018

This paper proposes a cost-effective technique to determine geomechanical properties and in-situ stress from borehole deformation data. In this approach, an artificial neural network (ANN) is applied to map the relationship among in-situ stress, borehole size, geomechanical properties, and borehole displacements. The genetic algorithm (GA) searches for the set of unknown stresses and geomechanical properties that matches the objective borehole deformation function. Probabilistic recapitulation (PR) analysis is conducted after each ANN-GA modeling cycle and will be repeated with a reduced number of unknowns for the next ANN-GA modeling cycle until unequivocal results are achieved. The PR-GA-ANN method has been demonstrated by a field case study to estimate borehole size, Young’s modulus, Poisson’s ratio, and the two horizontal stresses using borehole deformation information reported from four-arm caliper log of a vertical borehole. The methodology effectively solves the issue of the multiple solutions (various rock mechanical properties and in-situ stresses combinations) for a certain borehole deformation. The case study also indicated that the calculated horizontal stresses are in reasonable agreement with the filed hydraulic fracture treatment observations and the reported regional stress study of the area.
A Free-Piston Linear Generator Control Strategy for Improving Output Power
Authors: Zhang Chi , Chen Feixue , Li Long , Xu Zhaoping , Liu Liang , Yang Guilin , Lian Hongyuan , Tian Yingzhong
Published: January 2018

This paper presents a control strategy to improve the output power for a single-cylinder two-stroke free-piston linear generator (FPLG). The comprehensive simulation model of this FPLG is established and the operation principle is introduced. The factors that affect the output power are analyzed theoretically. The characteristics of the piston motion are studied. Considering the different features of the piston motion respectively in acceleration and deceleration phases, a ladder-like electromagnetic force control strategy is proposed. According to the status of the linear electric machine, the reference profile of the electromagnetic force is divided into four ladder-like stages during one motion cycle. The piston motions, especially the dead center errors, are controlled by regulating the profile of the electromagnetic force. The feasibility and advantage of the proposed control strategy are verified through comparison analyses with two conventional control strategies via MatLab/Simulink. The results state that the proposed control strategy can improve the output power by around 7–10% with the same fuel cycle mass.
Variance Characteristics of Tropical Radiosonde Winds Using a Vector-Tensor Method
Authors: Tieo Jing-Jin , Koh Tieh-Yong , Skote Martin , Srikanth Narasimalu
Published: January 2018

In this paper, an exploratory study on the variance characteristics of upper-air winds in a near-equator monsoon region is presented. The data were obtained from historical radiosonde observations from up to 250 stations within the region of interest for the period between 1954 and 2013. An alternative method based on vector statistics was employed in this study which characterises the mean by a vector and the variance by a tensor. Unlike the conventional approach of using scalar wind speeds, this vector-tensor approach allows the directional properties of the variance to be studied. A suite of statistics to describe the geometric properties of the variance tensor was also developed. These characterise the size of the variance, its degree of anisotropy, and the alignment of the preferred direction (if anisotropy is present) with the direction of the mean wind vector. Through analysis of these statistics, several salient trends were observed for the middle troposphere. It was found that the variance size and anisotropy exhibit significant variation with height whereas the alignment with the mean vector varies with the mean wind magnitude instead. It was also found that the scalar variance increases with mean wind speed.
Informatics Solution for Energy Efficiency Improvement and Consumption Management of Householders
Authors: Oprea Simona-Vasilica , Bâra Adela , Reveiu Adriana
Published: January 2018

Although in 2012 the European Union (EU) has promoted energy efficiency in order to ensure a gradual 20% reduction of energy consumption by 2020, its targets related to energy efficiency have increased and extended to new time horizons. Therefore, in 2016, a new proposal for 2030 of energy efficiency target of 30% has been agreed. However, during the last years, even if the electricity consumption by households decreased in the EU-28, the largest expansion was recorded in Romania. Taking into account that the projected consumption peak is increasing and energy consumption management for residential activities is an important measure for energy efficiency improvement since its ratio from total consumption can be around 25–30%, in this paper, we propose an informatics solution that assists both electricity suppliers/grid operators and consumers. It includes three models for electricity consumption optimization, profiles, clustering and forecast. By this solution, the daily operation of appliances can be optimized and scheduled to minimize the consumption peak and reduce the stress on the grid. For optimization purpose, we propose three algorithms for shifting the operation of the programmable appliances from peak to off-peak hours. This approach enables the supplier to apply attractive time-of-use tariffs due to the fact that by flattening the consumption peak, it becomes more predictable, and thus improves the strategies on the electricity markets. According to the results of the optimization process, we compare the proposed algorithms emphasizing the benefits. For building consumption profiles, we develop a clustering algorithm based on self-organizing maps. By running the algorithm for three scenarios, well-delimited profiles are obtained. As for the consumption forecast, highly accurate feedforward artificial neural networks algorithm with backpropagation is implemented. Finally, we test these algorithms using several datasets showing their performance and integrate them into a web-service informatics solution as a prototype.
Analytical Investigation of the Heat-Transfer Limits of a Novel Solar Loop-Heat Pipe Employing a Mini-Channel Evaporator
Authors: Diallo Thierno , Yu Min , Zhou Jinzhi , Zhao Xudong , Ji Jie , Hardy David
Published: January 2018

This paper presents an analytical investigation of heat-transfer limits of a novel solar loop-heat pipe developed for space heating and domestic hot water use. In the loop-heat pipe, the condensate liquid returns to the evaporator via small specially designed holes, using a mini-channel evaporator. The study considered the commonly known heat-transfer limits of loop-heat pipes, namely, the viscous, sonic, entrainment, boiling and heat-transfer limits due to the two-phase pressure drop in the loop. The analysis considered the main factors that affect the limits in the mini-channel evaporator: the operating temperature, mini-channel aspect ratio, evaporator length, evaporator inclination angle, evaporator-to-condenser height difference and the dimension of the holes. It was found that the entrainment is the main governing limit of the system operation. With the specified loop design and operational conditions, the solar loop-heat pipe can achieve a heat-transport capacity of 725 W. The analytical model presented in this study can be used to optimise the heat-transfer capacity of the novel solar loop-heat pipe.
Numerical Simulation of the Thermal Performance of a Dry Storage Cask for Spent Nuclear Fuel
Authors: Chang Heui-Yung , Chen Rong-Horng , Lai Chi-Ming
Published: January 2018

In this study, the heat flow characteristics and thermal performance of a dry storage cask were investigated via thermal flow experiments and a computational fluid dynamics (CFD) simulation. The results indicate that there are many inner circulations in the flow channel of the cask (the channel width is 10 cm). These circulations affect the channel airflow efficiency, which in turn affects the heat dissipation of the dry storage cask. The daily operating temperatures at the top concrete lid and the upper locations of the concrete cask are higher than those permitted by the design specification. The installation of the salt particle collection device has a limited negative effect on the thermal dissipation performance of the dry storage cask.
Isobaric Expansion Engines: New Opportunities in Energy Conversion for Heat Engines, Pumps and Compressors
Authors: Glushenkov Maxim , Kronberg Alexander , Knoke Torben , Kenig Eugeny
Published: January 2018

Isobaric expansion (IE) engines are a very uncommon type of heat-to-mechanical-power converters, radically different from all well-known heat engines. Useful work is extracted during an isobaric expansion process, i.e., without a polytropic gas/vapour expansion accompanied by a pressure decrease typical of state-of-the-art piston engines, turbines, etc. This distinctive feature permits isobaric expansion machines to serve as very simple and inexpensive heat-driven pumps and compressors as well as heat-to-shaft-power converters with desired speed/torque. Commercial application of such machines, however, is scarce, mainly due to a low efficiency. This article aims to revive the long-known concept by proposing important modifications to make IE machines competitive and cost-effective alternatives to state-of-the-art heat conversion technologies. Experimental and theoretical results supporting the isobaric expansion technology are presented and promising potential applications, including emerging power generation methods, are discussed. It is shown that dense working fluids with high thermal expansion at high process temperature and low compressibility at low temperature make it possible to operate with reasonable thermal efficiencies at ultra-low heat source temperatures (70–100 °C). Regeneration/recuperation of heat can increase the efficiency notably and extend the area of application of these machines to higher heat source temperatures. For heat source temperatures of 200–600 °C, the efficiency of these machines can reach 20–50% thus making them a flexible, economical and energy efficient alternative to many today’s power generation technologies, first of all organic Rankine cycle (ORC).
Introducing a Regulatory Policy Framework of Bait Fishing in European Coastal Lagoons: The Case of Ria de Aveiro in Portugal
Authors: Xenarios Stefanos , Queiroga Henrique , Lillebø Ana , Aleixo Ana
Published: January 2018

The harvesting of bait through digging in coastal mudflats is practiced for recreational and commercial purposes in European coastal systems including the Ria de Aveiro coastal lagoon on the northwest Atlantic coast of Portugal. The scale of harvesting in the Ria de Aveiro has recently increased due to the current economic climate in Portugal, with targeting of the polychaete, Diopatra neapolitana species or “casulo” as it is widely known in the Aveiro region. The national authorities have attempted to control casulo digging by issuing a regulation (Ordinance) in 2014 on the maximum daily catch limit to be caught by each individual. The daily catch limit is intended to represent the Maximum Sustainable Yield (MSY) for casulo beyond which overfishing will occur. The monitoring of the regulatory measures is expected to be conducted through on-site inspections in the digging areas. However, weak law enforcement was noticed, while there is also controversy over the daily catch limit (quota) stipulated by the Ordinance. To this end, the current study attempted to assess digging activities through remote monitoring and random inspections for a better policy enforcement of the national regulation. In addition, different harvesting scenarios were employed through a simplified bioeconomic model to attribute the current and future harvesting trends of bait digging in Aveiro coastal lagoon. The study findings indicate that remote monitoring coupled with some onsite interviews could be a more effective approach for the implementation of the current bait digging policy. Further, the results point to a distinctive discrepancy between the daily catch amount (MSY) introduced by the national legislation and the study findings which should be further scrutinized. The diggers seem to have reached the sustainable harvest identified by the present research. The current economic hardship in Portugal and the low profitability in similar employment sectors will possibly attract more diggers and increase harvesting in the near future. An increased harvest would likely trigger overfishing of D. neapolitana with unknown consequences for the population of the species as well as the aquatic ecosystem. The socio-economic and environmental effects are yet to be further clarified with more detailed data and advanced modeling techniques to ensure the sustainability of the activity.
Thyme and Savory Essential Oil Vapor Treatments Control Brown Rot and Improve the Storage Quality of Peaches and Nectarines, but Could Favor Gray Mold
Authors: Santoro Karin , Maghenzani Marco , Chiabrando Valentina , Bosio Pietro , Gullino Maria , Spadaro Davide , Giacalone Giovanna
Published: January 2018

The effect of biofumigation, through slow-release diffusors, of thyme and savory essential oils (EO), was evaluated on the control of postharvest diseases and quality of peaches and nectarines. EO fumigation was effective in controlling postharvest rots. Naturally contaminated peaches and nectarines were exposed to EO vapors for 28 days at 0 °C in sealed storage cabinets and then exposed at 20 °C for five days during shelf-life in normal atmosphere, simulating retail conditions. Under low disease pressure, most treatments significantly reduced fruit rot incidence during shelf-life, while, under high disease pressure, only vapors of thyme essential oil at the highest concentration tested (10% v/v in the diffusor) significantly reduced the rots. The application of thyme or savory EO favored a reduction of brown rot incidence, caused by Monilinia fructicola, but increased gray mold, caused by Botrytis cinerea. In vitro tests confirmed that M. fructicola was more sensitive to EO vapors than B. cinerea. Essential oil volatile components were characterized in storage cabinets during postharvest. The antifungal components of the essential oils increased during storage, but they were a low fraction of the volatile organic compounds in storage chambers. EO vapors did not influence the overall quality of the fruit, but showed a positive effect in reducing weight loss and in maintaining ascorbic acid and carotenoid content. The application of thyme and savory essential oil vapors represents a promising tool for reducing postharvest losses and preserving the quality of peaches and nectarines.
The Variable Rotation Measure Distribution in 3C 273 on Parsec Scales
Authors: Wardle John
Published: January 2018

We briefly review how opacity affects the observed polarization in synchrotron emitting jets. We show some new multi-frequency observations of 3C 273 made with the VLBA in 1999–2000, which add significantly to the available rotation measure (RM) observations of this source. Our findings can be summarized as follows: (1) The transverse gradient in RM is amply confirmed. This implies a toroidal component to the magnetic field, which in turn requires a current of 1017–1018 A flowing down the jet. (2) The net magnetic field in the jet is longitudinal; however, whether or not the longitudinal component is vector-ordered is an open question. (3) The RM distribution is variable on timescales of months to years. We attribute this to the motion of superluminal components behind a turbulent Faraday screen that surrounds the jet. (4) Finally, we suggest that Faraday rotation measurements at higher resolution and higher frequencies, with the Event Horizon Telescope, may enable useful constraints to be placed on the accretion rate onto the central black hole.
Quantum-Gravitational Effects on Primordial Power Spectra in Slow-Roll Inflationary Models
Authors: Brizuela David , Krämer Manuel
Published: January 2018

We review the computation of the power spectra of inflationary gauge-invariant perturbations in the context of canonical quantum gravity for generic slow-roll models. A semiclassical approximation, based on an expansion in inverse powers of the Planck mass, is applied to the complete Wheeler–DeWitt equation describing a perturbed inflationary universe. This expansion leads to a hierarchy of equations at consecutive orders of the approximation and allows us to write down a corrected Schrödinger equation that encodes information about quantum-gravitational effects. The analytical dependence of the correction to the power spectrum on the wavenumber is obtained. Nonetheless, some numerical work is needed in order to obtain its precise value. Finally, it is shown that the correction turns out to be positive, which leads to an enhancement of the power spectrum especially prominent for large scales. We will also discuss whether this correction leads to a measurable effect in the cosmic microwave background anisotropies.
A Bathymetry- and Reflectivity-Based Approach for Seafloor Segmentation
Authors: Masetti Giuseppe , Mayer Larry , Ward Larry
Published: January 2018

A robust and flexible technique to segment seafloor acoustic mapping data by analyzing co-located bathymetric digital elevation models and acoustic backscatter mosaics is presented. The algorithm first uses principles of topographic openness, pattern recognition, and texture classification to identify geomorphic elements of the seafloor or “area kernels”, and then derives the final seafloor segmentation by merging or splitting the kernels based on principles of similarity and multi-modality. The output is a collection of homogeneous, non-overlapping seafloor segments of consistent morphology and acoustic backscatter texture. Each labeled segment is enriched by a list of derived, physically-meaningful attributes that can be used for subsequent task-specific analysis.