bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemically-Induced Production of Anti-Inflammatory Molecules in Microalgae
Authors: Montero-Lobato Zaida , Vázquez María , Navarro Francisco , Fuentes Juan Luis , Bermejo Elisabeth , Garbayo Inés , Vílchez Carlos , Cuaresma María
Published: November 2018

Microalgae have been widely recognized as a valuable source of natural, bioactive molecules that can benefit human health. Some molecules of commercial value synthesized by the microalgal metabolism have been proven to display anti-inflammatory activity, including the carotenoids lutein and astaxanthin, the fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), and sulphated polysaccharides. These molecules can accumulate to a certain extent in a diversity of microalgae species. A production process could become commercially feasible if the productivity is high and the overall production process costs are minimized. The productivity of anti-inflammatory molecules depends on each algal species and the cultivation conditions, the latter being mostly related to nutrient starvation and/or extremes of temperature and/or light intensity. Furthermore, novel bioprocess tools have been reported which might improve the biosynthesis yields and productivity of those target molecules and reduce production costs simultaneously. Such novel tools include the use of chemical triggers or enhancers to improve algal growth and/or accumulation of bioactive molecules, the algal growth in foam and the surfactant-mediated extraction of valuable compounds. Taken together, the recent findings suggest that the combined use of novel bioprocess strategies could improve the technical efficiency and commercial feasibility of valuable microalgal bioproducts production, particularly anti-inflammatory compounds, in large scale processes.
Review of Recent Nuclear Magnetic Resonance Studies of Ion Transport in Polymer Electrolytes
Authors: Munoz Stephen , Greenbaum Steven
Published: November 2018

Current and future demands for increasing the energy density of batteries without sacrificing safety has led to intensive worldwide research on all solid state Li-based batteries. Given the physical limitations on inorganic ceramic or glassy solid electrolytes, development of polymer electrolytes continues to be a high priority. This brief review covers several recent alternative approaches to polymer electrolytes based solely on poly(ethylene oxide) (PEO) and the use of nuclear magnetic resonance (NMR) to elucidate structure and ion transport properties in these materials.
Monolithic Low Noise and Low Zero-g Offset CMOS/MEMS Accelerometer Readout Scheme
Authors: Liu Yu-Sian , Wen Kuei-Ann
Published: November 2018

A monolithic low noise and low zero-g offset CMOS/MEMS accelerometer and readout scheme in standard 0.18 μm CMOS mixed signal UMC process is presented. The low noise chopper architecture and telescopic topology is developed to achieve low noise. The experiments show noise floor is 421.70 μg/√Hz. The whole system has 470 mV/g sensitivity. The power consumption is about 1.67 mW. The zero-g trimming circuit reduces the offset from 1242.63 mg to 2.30 mg.
Systematic Profiling of the Multicomponents and Authentication of Erzhi Pill by UHPLC/Q-Orbitrap-MS Oriented Rapid Polarity-Switching Data-Dependent Acquisition and Selective Monitoring of the Chemical Markers Deduced from Fingerprint Analysis
Authors: Jia Li , Fu Lingling , Wang Xiaoyan , Yang Wenzhi , Wang Hongda , Zuo Tiantian , Zhang Chunxia , Hu Ying , Gao Xiumei , Han Lifeng
Published: November 2018

The analytical platform UHPLC/Q-Orbitrap-MS offers a solution to quality investigation of TCM with high definiteness. Using Erzhi Pill (EZP) as a case, we developed UHPLC/Q-Orbitrap-MS based approaches to achieve systematic multicomponent identification and rapid authentication. Comprehensive multicomponent characterization of EZP was performed by negative/positive switching data-dependent high-energy collision-induced dissociation-MS2 (HCD-MS2) after 25 min chromatographic separation. By reference compounds comparison, elemental composition analysis, fragmentation pathways interpretation, and retrieval of an in-house library, 366 compounds were separated and detected from EZP, and 96 thereof were structurally characterized. The fingerprints of two component drugs (Ligustri Lucidi Fructus, LLF; Ecliptae Herba, EH) for EZP were analyzed under the same LC-MS condition by full scan in negative mode. In combination with currently available pharmacological reports, eight compounds were deduced as the ‘identity markers’ of EZP. Selective ion monitoring (SIM) of eight marker compounds was conducted to authenticate six batches of EZP samples. Both LLF and EH could be detected from all EZP samples by analyzing the SIM spectra, which could indicate their authenticity. Conclusively, UHPLC/Q-Orbitrap-MS by rapid polarity switching could greatly expand the potency of untargeted profiling with high efficiency, and SIM of multiple chemical markers rendered a practical approach enabling the authentication of TCM formulae.
Binding Study of the Fluorescent Carbazole Derivative with Human Telomeric G-Quadruplexes
Authors: Głuszyńska Agata , Juskowiak Bernard , Rubiś Błażej
Published: November 2018

The carbazole ligand 3 was synthesized, characterized and its binding interactions with human telomeric (22HT) G-quadruplex DNA in Na+ and K+-containing buffer were investigated by ultraviolet-visible (UV-Vis) spectrophotometry, fluorescence, circular dichroism (CD) spectroscopy, and DNA melting. The results showed that the studied carbazole ligand interacted and stabilized the intramolecular G-quadruplexes formed by the telomeric sequence in the presence of sodium and potassium ions. In the UV-Vis titration experiments a two-step complex formation between ligand and G-quadruplex was observed. Very low fluorescence intensity of the carbazole derivative in Tris HCl buffer in the presence of the NaCl or KCl increased significantly after addition of the 22HT G4 DNA. Binding stoichiometry of the ligand/G-quadruplex was investigated with absorbance-based Job plots. Carbazole ligand binds 22HT with about 2:1 stoichiometry in the presence of sodium and potassium ions. The binding mode appeared to be end-stacking with comparable binding constants of ~105 M−1 as determined from UV-Vis and fluorescence titrations data. The carbazole ligand is able to induce formation of G4 structure of 22HT in the absence of salt, which was proved by CD spectroscopy and melting studies. The derivative of carbazole 3 shows significantly higher cytotoxicity against breast cancer cells then for non-tumorigenic breast epithelial cells. The cytotoxic activity of ligand seems to be not associated with telomerase inhibition.
A Phenomenological Framework of Architectural Paradigms for the User-Centered Design of Virtual Environments
Authors: Gladden Matthew E.
Published: November 2018

In some circumstances, immersion in virtual environments with the aid of virtual reality (VR) equipment can create feelings of anxiety in users and be experienced as something “frightening”, “oppressive”, “alienating”, “dehumanizing”, or “dystopian”. Sometimes (e.g., in exposure therapy or VR gaming), a virtual environment is intended to have such psychological impacts on users; however, such effects can also arise unintentionally due to the environment’s poor architectural design. Designers of virtual environments may employ user-centered design (UCD) to incrementally improve a design and generate a user experience more closely resembling the type desired; however, UCD can yield suboptimal results if an initial design relied on an inappropriate architectural approach. This study developed a framework that can facilitate the purposeful selection of the most appropriate architectural approach by drawing on Norberg-Schulz’s established phenomenological account of real-world architectural modes. By considering the unique possibilities for structuring and experiencing space within virtual environments and reinterpreting Norberg-Schulz’s schemas in the context of virtual environment design, a novel framework was formulated that explicates six fundamental “architectural paradigms” available to designers of virtual environments. It was shown that the application of this framework could easily be incorporated as an additional step within the UCD process.
Biodegradation of Microplastic Derived from Poly(ethylene terephthalate) with Bacterial Whole-Cell Biocatalysts
Authors: Gong Jixian , Kong Tongtong , Li Yuqiang , Li Qiujin , Li Zheng , Zhang Jianfei
Published: November 2018

At present, the pollution of microplastic directly threatens ecology, food safety and even human health. Polyethylene terephthalate (PET) is one of the most common of microplastics. In this study, the micro-size PET particles were employed as analog of microplastic. The engineered strain, which can growth with PET as sole carbon source, was used as biocatalyst for biodegradation of PET particles. A combinatorial processing based on whole-cell biocatalysts was constructed for biodegradation of PET. Compared with enzymes, the products can be used by strain growth and do not accumulated in culture solution. Thus, feedback inhibition of products can be avoided. When PET was treated with the alkaline strain under high pH conditions, the product concentration was higher and the size of PET particles decreased dramatically than that of the biocatalyst under neutral conditions. This shows that the method of combined processing of alkali and organisms is more efficient for biodegradation of PET. The novel approach of combinatorial processing of PET based on whole-cell biocatalysis provides an attractive avenue for the biodegradation of micplastics.
Effect of Bidispersity on Dynamics of Confined Polymer Films
Authors: Li Sijia , Chen Qiaoyue , Ding Mingming , Shi Tongfei
Published: November 2018

Using Monte Carlo simulations, we studied the effect of bidispersity on the dynamics of polymer films capped between two neutral walls, where we chose three representative compositions for bidispersed polymer films. Our results demonstrate that the characteristic entanglement length is an important parameter to clarify the effect of the bidispersity on the dynamics of polymer films. For the short chains, shorter than the characteristic entanglement length, the average number of near-neighboring particles increases with the decrease of the film thickness and limits the diffusivity of the short chains, which is independent of the film compositions. However, the dynamics of the long chains, of which is above the characteristic entanglement length, is determined by the film’s composition. In our previous paper, we inferred from the structures and entanglements of the bidisperse system with short and long chains that the constraint release contributes significantly to the relaxation mechanism of long chains. By calculating the self-diffusion coefficient of long chains, we confirmed this prediction that, with a lower weight fraction of long chains, the self-diffusion coefficient of long chains decreases slowly with the decrease of the film thickness, which is similar to that of short chains. With a higher weight fraction of long chains, the competition between the disentanglement and the increased in the local degree of confinement which resulted in the self-diffusion coefficient of long chains varying non-monotonically with the film thickness. Furthermore, for the bidisperse system with long and long chains, the diffusivity of long chains was not affected by the constraint release, which varied nonmonotonically with the decrease of the film thickness due to the competition between the disentanglement and the enhanced confinement. Herein, compared with the previous work, we completely clarified the relationship between the structures and dynamics for three representative compositions of bidisperse polymer films, which contains all possible cases for bidisperse systems. Our work not only establishes a unified understanding of the dependency of dynamics on the bidispersity of polymer films, but also helps to understand the case of polydispersity, which can provide computational supports for various applications for polymer films.
Parameter Identification For Continuous Fluidized Bed Spray Agglomeration
Authors: Golovin Ievgen , Strenzke Gerd , Dürr Robert , Palis Stefan , Bück Andreas , Tsotsas Evangelos , Kienle Achim
Published: November 2018

Agglomeration represents an important particle formation process used in many industries. One particularly attractive process setup is continuous fluidized bed spray agglomeration, which features good mixing as well as high heat and mass transfer on the one hand and constant product throughput with constant quality as well as high flow rates compared to batch mode on the other hand. Particle properties such as agglomerate size or porosity significantly affect overall product properties such as re-hydration behavior and dissolubility. These can be influenced by different operating parameters. In this manuscript, a population balance model for a continuous fluidized bed spray agglomeration is presented and adapted to experimental data. Focus is on the description of the dynamic behavior in continuous operation mode in a certain neighborhood around steady-state. Different kernel candidates are evaluated and it is shown that none of the kernels are able to match the first six minutes with time independent parameters. Afterwards, a good fit can be obtained, where the Brownian and the volume independent kernel models match best with the experimental data. Model fit is improved for identification on a shifted time domain neglecting the initial start-up phase. Here, model identifiability is shown and parameter confidence intervals are computed via parametric bootstrap.
Taking Divination Seriously: From Mumbo Jumbo to Worldviews and Ways of Life
Authors: Silva Sónia
Published: November 2018

The peripheral role of divination in religious studies reflects centuries of misrepresentation and depreciation in the textual record. This long history dates back to the travel literature of early modern times, particularly in West Africa, where two stereotypical themes took form: divination as mumbo jumbo, and the diviners as charlatans who shamelessly deceive their credulous clients. These two stereotypical themes persisted through the anthropological discourse about African divination until the 1970s. To undo this long history of misrepresentation and depreciation, a change of analytical focus from reified differences to similar engagement with broad ideas and big questions is in order. By considering a particular case study—basket divination in northwest Zambia—through the theoretical lens of worldviews and ways of life, it becomes possible to take divination seriously and grant it a more central place in religious studies. Four broad, inclusive ideas or big questions emerge from the ethnography of basket divination in northwest Zambia: ontology, epistemology, praxeology, and the place of suffering in human existence.
Sea Surface Temperature Retrieval from the First Korean Geostationary Satellite COMS Data: Validation and Error Assessment
Authors: Woo Hye-Jin , Park Kyung-Ae , Li Xiaofeng , Lee Eun-Young
Published: November 2018

Korea’s first geostationary satellite, the “Communication, Ocean, and Meteorological Satellite” (COMS), has been operating since 2010. The Meteorological Imager (MI), an sensor on-board the COMS, has observed sea-surface radiances for the estimation of sea surface temperature (SST) in the western Pacific Ocean and eastern Indian Ocean. To derive the SST coefficients of COMS, quality-controlled surface drifting buoy data were collected for the period of April 2011 to March 2015. A collocation procedure between COMS/MI data and the surface drifter data produced a matchup database for 4 years from 2011 to 2015. The coefficients for the COMS/MI SST were derived by applying appropriate algorithms, i.e., the Multi-channel SST (MCSST) and Non-linear SST (NLSST) algorithms, for daytime and nighttime data using a regression method. Validation results suggest the possibility of the continuous use of the coefficients as representative SST coefficients of COMS. The estimated SSTs near the edge of a full disk with high satellite zenith angles over 60° revealed relatively large errors compared to drifter temperatures. Most of NLSST formulations exhibited overestimation of SSTs at low SSTs (<10 °C). This study suggests an approach by which SST can be measured accurately in order to contribute to tracking climate change.
Inversion of Nearshore X-Band Radar Images to Sea Surface Elevation Maps
Authors: Chernyshov Pavel , Vrecica Teodor , Toledo Yaron
Published: November 2018

A new method to invert X-band radar images for linear shoaling conditions is proposed. The commonly used approach for this type of inverse problems is the Fourier transform. Unlike in deep water conditions, in the shoaling region, waves are modulated both in terms of wavelength and amplitude. However, Fourier analysis assumes spacial and temporal periodicity, and homogeneity limiting its applicability to this region. In order to overcome these limitations, a wavelet based technique is developed. The proposed technique treats every spatial radar image within the time sequence individually, so no information on the dispersion relation is required. For validation purposes, surface elevation range-time shoaling realizations based on the mild slope equation are prepared. A radar imaging model including tilt and shadowing modulations, speckle noise, and the radar equation is applied to these realizations to provide modeled grazing incidence radar images. The inversion process starts with the application of the continuous wavelet transform independently for each spacial image. The procedure continues with employing a successive range independent modulation transfer function to the wavelet spectra in the wavenumber domain. Then, after a phase shift correction, an inverse continuous wavelet transform is applied. The procedure is finalized by a calibration of the retrieved maps. After the calibration, a thorough comparison between the original and the reconstructed surface elevations is performed. It shows high efficiency of the proposed method in treating wave number and amplitude modulated signals, as well as in addressing local phase shifts due to tilt modulation and noise contamination. The new inversion method is proven to have high accuracy in inhomogeneous conditions. It shows high potential to be implemented for individual wave reconstruction using real aperture radars.
Capabilities of Chinese Gaofen-3 Synthetic Aperture Radar in Selected Topics for Coastal and Ocean Observations
Authors: Li Xiao-Ming , Zhang Tianyu , Huang Bingqing , Jia Tong
Published: November 2018

Gaofen-3 (GF-3), the first Chinese spaceborne synthetic aperture radar (SAR) in C-band for civil applications, was launched on August 2016. Some studies have examined the use of GF-3 SAR data for ocean and coastal observations, but these studies generally focus on one particular application. As GF-3 has been in operation over two years, it is essential to evaluate its performance in ocean observation, a primary goal of the GF-3 launch. In this paper, we offer an overview demonstrating the capabilities of GF-3 SAR in ocean and coastal observations by presenting several representative cases, i.e., the monitoring of intertidal flats, offshore tidal turbulent wakes and oceanic internal waves, to highlight the GF-3’s full polarimetry, high spatial resolution and wide-swath imaging advantages. Moreover, we also present a detailed analysis of the use of GF-3 quad-polarization data for sea surface wind retrievals and wave mode data for sea surface wave retrievals. The case studies and statistical analysis suggest that GF-3 has good ocean and coastal monitoring capabilities, though further improvements are possible, particularly in radiometric calibration and stable image quality.
Leak Detection in Water Pipes Using Submersible Optical Optic-Based Pressure Sensor
Authors: Wong Leslie , Deo Ravin , Rathnayaka Suranji , Shannon Benjamin , Zhang Chunshun , Chiu Wing Kong , Kodikara Jayantha , Widyastuti Hera
Published: November 2018

Leakage is undesirable in water distribution networks, as leaky pipes are financially costly both to water utilities and consumers. The ability to detect, locate, and quantify leaks can significantly improve the service delivered. Optical fibre sensors (OFS) have previously demonstrated their capabilities in performing real-time and continuous monitoring of pipe strength leak detection. However, the challenge remains due to the high labour cost and time-consuming process for the installation of optical fibre sensors to existing buried pipelines. The aim of this paper is to evaluate the feasibility of a submersible optical fibre-based pressure sensor that can be deployed without rigid bonding to the pipeline. This paper presents a set of experiments conducted using the proposed sensing strategy for leak detection. The calibrated optical fibre device was used to monitor the internal water pressure in a pipe with simultaneous verification from a pressure gauge. Two different pressure-based leak detection methods were explored. These leak detection methods were based on hydrostatic and pressure transient responses of the optical fibre pressure sensor. Experimental results aided in evaluating the functionality, reliability, and robustness of the submersible optical fibre pressure sensor.
Dynamic Balance Measurement and Quantitative Assessment Using Wearable Plantar-Pressure Insoles in a Pose-Sensed Virtual Environment
Authors: Lou Cunguang , Pang Chenyao , Jing Congrui , Wang Shuo , He Xufeng , Liu Xiaoguang , Huang Lei , Lin Feng , Liu Xiuling , Wang Hongrui
Published: November 2018

The center of plantar pressure (COP) reflects the dynamic balance of subjects to a certain extent. In this study, wearable pressure insoles are designed, body pose measure is detected by the Kinect sensor, and a balance evaluation system is formulated. With the designed games for the interactive actions, the Kinect sensor reads the skeletal poses to judge whether the desired action is performed, and the pressure insoles simultaneously collect the plantar pressure data. The COP displacement and its speed are calculated to determine the body sway and the ability of balance control. Significant differences in the dispersion of the COP distribution of the 12 subjects have been obtained, indicating different balancing abilities of the examined subjects. A novel assessment process is also proposed in the paper, in which a correlation analysis is made between the de facto sit-to-stand (STS) test and the proposed method; the Pearson and Spearman correlations are also conducted, which reveal a significant positive correlation. Finally, four undergraduate volunteers with a right leg sports injury participate in the experiments. The experimental results show that the normal side and abnormal side have significantly different characters, suggesting that our method is effective and robust for balance measurements.
Comparison of Different Algorithms for Calculating Velocity and Stride Length in Running Using Inertial Measurement Units
Authors: Zrenner Markus , Gradl Stefan , Jensen Ulf , Ullrich Martin , Eskofier Bjoern M.
Published: November 2018

Running has a positive impact on human health and is an accessible sport for most people. There is high demand for tracking running performance and progress for amateurs and professionals alike. The parameters velocity and distance are thereby of main interest. In this work, we evaluate the accuracy of four algorithms, which calculate the stride velocity and stride length during running using data of an inertial measurement unit (IMU) placed in the midsole of a running shoe. The four algorithms are based on stride time, foot acceleration, foot trajectory estimation, and deep learning, respectively. They are compared using two studies: a laboratory-based study comprising 2377 strides from 27 subjects with 3D motion tracking as a reference and a field study comprising 12 subjects performing a 3.2-km run in a real-world setup. The results show that the foot trajectory estimation algorithm performs best, achieving a mean error of 0.032 ± 0.274 m/s for the velocity estimation and 0.022 ± 0.157 m for the stride length. An interesting alternative for systems with a low energy budget is the acceleration-based approach. Our results support the implementation decision for running velocity and distance tracking using IMUs embedded in the sole of a running shoe.
BeiDou Satellite Unhealthy States and the Impact on System Performance
Authors: Hu Caibo , Shi Chuang , Chen Jinping , Lou Yidong , Wang Fei
Published: November 2018

The BeiDou system satellites may be unhealthy due to many reasons, affecting system performance in different ways. Therefore, it is important to analyze the causes and characteristics of the satellites’ unhealthy states. In this study, these states are classified into five types based on the broadcast ephemeris. Three criteria are presented, based on which a general classification method is proposed. Data from July 2017 to June 2018 are analyzed to validate the method, from which we know that the average unhealthy duration due to satellite maneuvers is much longer than the duration of unhealthy states related to satellite orbit or clock anomalies, and the other unhealthy states may be caused by inbound or outbound satellites. Statistics show that most of the time, the number of unhealthy satellites is no more than two and the average positioning accuracy in the service area will decrease by no more than 0.75 and 1.2 meters when one or two BDS satellites are unhealthy, respectively.
Velocity-Adaptive V2I Fair-Access Scheme Based on IEEE 802.11 DCF for Platooning Vehicles
Authors: Wu Qiong , Xia Siyang , Fan Pingyi , Fan Qiang , Li Zhengquan
Published: November 2018

Platooning strategy is an important component of autonomous driving technology. Autonomous vehicles in platoons are often equipped with a variety of on-board sensors to detect the surrounding environment. The abundant data collected by autonomous vehicles in platoons can be transmitted to the infrastructure through vehicle-to-infrastructure (V2I) communications using the IEEE 802.11 distributed coordination function (DCF) mechanism and then uploaded to the cloud platform through the Internet. The cloud platform extracts useful information and then sends it back to the autonomous vehicles respectively. In this way, autonomous vehicles in platoons can detect emergency conditions and make a decision in time. The characteristics of platoons would cause a fair-access problem in the V2I communications, i.e., vehicles in the platoons moving on different lanes with different velocities would have different resident time within the infrastructure’s coverage and thus successfully send different amounts of data to the infrastructure. In this case, the vehicles with different velocities will receive different amounts of useful information from the cloud. As a result, vehicles with a higher velocity are more likely to suffer from a traffic accident as compared to the vehicles with a lower velocity. Hence, this paper considers the fair-access problem and proposes a fair-access scheme to ensure that vehicles with different velocities successfully transmit the same amount of data by adaptively adjusting the minimum contention window of each vehicle according to its velocity. Moreover, the normalized throughput of the proposed scheme is derived. The validity of the fair-access scheme is demonstrated by simulation.
A Sigma-Delta ADC for Signal Conditioning IC of Automotive Piezo-Resistive Pressure Sensors with over 80 dB SNR
Authors: Samadpoor Rikan Behnam , Kim Sang-Yun , Ahmad Nabeel , Abbasizadeh Hamed , Riaz Ur Rehman Muhammad , Shehzad Khuram , Hejazi Arash , E. Rad Reza , Verma Deeksha , Lee Kang-Yoon
Published: November 2018

This paper presents a second-order discrete-time Sigma-Delta (SD) Analog-to-Digital Converter (ADC) with over 80 dB Signal to Noise Ratio (SNR), which is applied in a signal conditioning IC for automotive piezo-resistive pressure sensors. To reduce the flicker noise of the structure, choppers are used in every stage of the high gain amplifiers. Besides, to reduce the required area and power, only the CIC filter structure is adopted as a decimation filter. This filter has a configurable structure that can be applied to different data rates and input signal bandwidths. The proposed ADC was fabricated and measured in a 0.18-µm CMOS process. Due to the application of only a CIC filter, the total active area of the SD-ADC and reference generator is 0.49 mm2 where the area of the decimation filter is only 0.075 mm2. For the input signal bandwidth of 1.22 kHz, it achieved over 80 dB SNR in a 2.5 MHz sampling frequency while consuming 646 µW power.
Suitable Combination of Direct Intensity Modulation and Spreading Sequence for LIDAR with Pulse Coding
Authors: Kim Gunzung , Park Yongwan
Published: November 2018

In the coded pulse scanning light detection and ranging (LIDAR) system, the number of laser pulses used at a given measurement point changes depending on the modulation and the method of spreading used in optical code-division multiple access (OCDMA). The number of laser pulses determines the pulse width, output power, and duration of the pulse transmission of a measurement point. These parameters determine the maximum measurement distance of the LIDAR and the number of measurement points that can be employed per second. In this paper, we suggest possible combinations of modulation and spreading technology that can be used for OCDMA, evaluate their performance and characteristics, and study optimal combinations according to varying operating environments.
Above-Threshold Queries of Environmental Conditions Based on Bilinear Interpolation in Wireless Sensor Networks
Authors: Liu Yaxi , Huangfu Wei , Zhang Haijun , Long Keping
Published: November 2018

Wireless sensor networks can be regarded as sensor database systems, which permit users to query sensor data of interest. Among various spatial database queries, we focus the area-wise aggregate queries in the region where the sensor values are above a predefined threshold, which are summarized as above-threshold queries. In this paper, we propose a novel Bilinear Interpolation-Based (BIB) algorithm, which utilizes the bilinear interpolation to estimate the environmental variables inside a grid with the known sensor values at the vertexes, to support the above-threshold queries for regularly-deployed sensor networks and provide the closed-form solution of the above-threshold ratio. We designate experiments with both the artificially-constructed environment data and the real temperature data. Experiment results manifest that the proposed BIB algorithm shows a good performance in estimating the above-threshold ratios to support the above-threshold queries in an accurate and efficient manner.
A Temporal Adaptive Access Mechanism for Data Fusion in an IoT Environment
Authors: Xu Jiuyun , Liu Shuang , Lu Xiaoxuan , Li Li , Liang Hongliang , Duan Qiang , Liu Runjie
Published: November 2018

Data fusion in the Internet of Things (IoT) environment demands collecting and processing a wide variety of data with mixed time characteristics, both real-time and non-real-time data. Most of the previous research on data fusion was about the data processing aspect; however, successful data transmission is a prerequisite for high-performance data fusion in IoT. On the other hand, research on data transmissions in IoT mainly focuses on networking without sufficiently considering the special requirements of the upper-layer applications, such as the data fusion process, that are consuming the transmitted data. In this paper, we tackle the problem of data transmission for data fusion in an IoT environment by proposing a distributed scheduling mechanism VD-CSMA in wireless sensor networks, which considers the values for data fusion, as well as the delay constraints of packets when determining their priority levels for transmission. Simulation results have shown that VD-CSMA may enhance both throughput and delay performance of data transmission as compared to the typical scheduling schemes used for data fusion in IoT.
Comparison of Different Feature Sets for TLS Point Cloud Classification
Authors: Li Quan , Cheng Xiaojun
Published: November 2018

Point cloud classification is an essential requirement for effectively utilizing point cloud data acquired by Terrestrial laser scanning (TLS). Neighborhood selection, feature selection and extraction, and classification of points based on the respective features constitute the commonly used workflow of point cloud classification. Feature selection and extraction has been the focus of many studies, and the choice of different features has had a great impact on classification results. In previous studies, geometric features were widely used for TLS point cloud classification, and only a few studies investigated the potential of both intensity and color on classification using TLS point cloud. In this paper, the geometric features, color features, and intensity features were extracted based on a supervoxel neighborhood. In addition, the original intensity was also corrected for range effect, which is why the corrected intensity features were also extracted. The different combinations of these features were tested on four real-world data sets. Experimental results demonstrate that both color and intensity features can complement the geometric features to help improve the classification results. Furthermore, the combination of geometric features, color features, and corrected intensity features together achieves the highest accuracy in our test.
Drive-By Bridge Frequency Identification under Operational Roadway Speeds Employing Frequency Independent Underdamped Pinning Stochastic Resonance (FI-UPSR)
Authors: Elhattab Ahmed , Uddin Nasim , OBrien Eugene
Published: November 2018

Recently, drive-by bridge inspection has attracted increasing attention in the bridge monitoring field. A number of studies have given confidence in the feasibility of the approach to detect, quantify, and localize damages. However, the speed of the inspection truck represents a major obstacle to the success of this method. High speeds are essential to induce a significant amount of kinetic energy to stimulate the bridge modes of vibration. On the other hand, low speeds are necessary to collect more data and to attenuate the vibration of the vehicle due to the roughness of the road and, hence, magnify the bridge influence on the vehicle responses. This article introduces Frequency Independent Underdamped Pinning Stochastic Resonance (FI-UPSR) as a new technique, which possesses the ability to extract bridge dynamic properties from the responses of a vehicle that passes over the bridge at high speed. Stochastic Resonance (SR) is a phenomenon where feeble information such as weak signals can be amplified through the assistance of background noise. In this study, bridge vibrations that are present in the vehicle responses when it passes over the bridge are the feeble information while the noise counts for the effect of the road roughness on the vehicle vibration. UPSR is one of the SR models that has been chosen in this study for its suitability to extract the bridge vibration. The main contributions of this article are: (1) introducing a Frequency Independent-Stochastic Resonance model known as the FI-UPSR and (2) implementing this model to extract the bridge vibration from the responses of a fast passing vehicle.
Therapeutic Effect Enhancement by Dual-Bias High-Voltage Circuit of Transmit Amplifier for Immersion Ultrasound Transducer Applications
Authors: Choi Hojong , Choe Se-woon
Published: November 2018

The dual-bias high-voltage circuit of a transmit amplifier for immersion ultrasound transducer applications is proposed to enhance the therapeutic effect of human HeLa cells. High-voltage output signals generated from a transmit amplifier are typically preferable for immersion ultrasound transducers owing to their high sensitivity at the desired frequency. However, high-voltage output signals typically produce high-order harmonic distortions, thus triggering several unwanted high-order spectral signals in the ultrasound transducers. By reducing high-order harmonic distortions, we expect that improving the signal quality of excited pulses for immersion ultrasound transducers would be beneficial for the therapeutic effect on human cervical cancer HeLa cell suppression. Therefore, an additional bias circuit is developed to merge with the original bias circuit for transmit amplifier to control the harmonic distortions of the immersion ultrasonic transducer. To properly select the components of dual-bias high-voltage circuit, we need to calculate and measure the DC bias voltages of the transmit amplifier with and without dual-bias high-voltage circuit for different period of the time for therapeutic applications. To evaluate the performances of the developed circuit, pulse-echo measurements using a transmit amplifier with or without dual-bias high-voltage circuit were obtained. The measured second, third, and fourth harmonic distortions of the echo signals when using the transmit amplifier with dual-bias high-voltage circuit at 10 V DC bias voltage are lower than those when using the transmit amplifier only. Subsequently, the therapeutic effects using the enhanced performances of the transmit amplifier with dual-bias high-voltage circuit were verified and compared with those using the performances of the transmit amplifier by comparison of quantitative changes in HeLa cell concentrations. The control group without any ultrasonic induction increased the cell density up to about 100% on Day4, however the experimental groups with ultrasonic induction (TA = 91.2 ± 0.8%, TA+Dual-bias high-voltage circuit (0.8 V) = 78.8 ± 1.7% and TA+Dual-bias high-voltage circuit (10 V) = 66.3 ± 1.1%) showed statistically significant cell density changes compared to the control group. We confirmed that the therapeutic effect from using the dual-bias high-voltage circuit is improved. Therefore, it can be a potential candidate to improve the therapeutic effect of HeLa cells.
Flexible Radio-Frequency Identification (RFID) Tag Antenna for Sensor Applications
Authors: Islam Mohammad , Alam Touhidul , Yahya Iskandar , Cho Mengu
Published: November 2018

In this paper, an inkjet-printed flexible Radio-Frequency Identification (RFID) tag antenna is proposed for an ultra-high frequency (UHF) sensor application. The proposed tag antenna facilitates a system-level solution for low-cost and faster mass production of RFID passive tag antenna. The tag antenna consists of a modified meander line radiator with a semi-circular shaped feed network. The structure is printed on photo paper using silver nanoparticle conductive ink. The generic design outline, as well as tag antenna performances for several practical application aspects are investigated. The simulated and measured results verify the coverage of universal UHF RFID band with an omnidirectional radiation pattern and a long-read range of 15 ft. In addition, the read range for different bending angles and lifetimes of the tag antenna are also demonstrated.
Perceived Importance of Smart and Sustainable Building Features from the Users’ Perspective
Authors: To Wai Ming , Lai Linda S. L. , Lam King Hang , Chung Andy W. L.
Published: November 2018

Smart and sustainable buildings have been designed, built and utilized in order to consume less energy, facilitate efficient building operation, and improve the comfort, health and productivity of users. Hence, they become a critical component of smart cities. Nonetheless, perceived importance rankings of different features of smart and sustainable buildings have yet to be identified and prioritized from the users’ perspective. Based on responses from 494 building users in Hong Kong, it was found that building users tended to focus more on intelligent security systems, followed by intelligent and responsive fresh air supply and lifts and escalators. On the other hand, building users generally considered the systems that monitor people’s movement and harvest rain water to be the least important features. Exploratory factor analyses were used to identify key factors of perceived smartness and sustainability of a building. The results of factor analyses showed that different user groups would characterize a building’s smartness differently.
Citizen Initiatives in the Post-Welfare State
Authors: Soares da Silva Diogo , Horlings Lummina , Figueiredo Elisabete
Published: November 2018

Recently we have seen the emergence of citizen-led community initiatives and civic enterprises, taking over governmental tasks in providing public services in various sectors, such as energy, care, landscape maintenance, and culture. This phenomenon can be explained by a renewed interest in community, place, and ‘local identity’; the erosion of the welfare state; the privatization of public services; a re-emergence of the social economy; and tensions between ‘bottom-up’ initiatives and the changing role of the state. The co-production of governments and initiatives can potentially result in a shift from government-led to community-led planning. This, however, raises questions about their innovative potential, the democratic consequences, and the potential roles of governments in enabling these societal dynamics. This article discusses these issues theoretically, illustrated with empirical examples from Portugal, the Netherlands, and Wales, in a context of uncertainty regarding the future of the traditional European welfare state.
The Effect of Altering Body Posture and Barbell Position on the Between-Session Reliability of Force-Time Curve Characteristics in the Isometric Mid-Thigh Pull
Authors: Guppy Stuart N. , Brady Claire J. , Kotani Yosuke , Stone Michael H. , Medic Nikola , Haff Guy Gregory
Published: November 2018

Seventeen strength and power athletes (n = 11 males, 6 females; height: 177.5 ± 7.0 cm, 165.8 ± 11.4 cm; body mass: 90.0 ± 14.1 kg, 66.4 ± 13.9 kg; age: 30.6 ± 10.4 years, 30.8 ± 8.7 years), who regularly performed weightlifting movements during their resistance training programs, were recruited to examine the effect of altering body posture and barbell position on the between-session reliability of force-time characteristics generated in the isometric mid-thigh pull (IMTP). After participants were familiarised with the testing protocol, they undertook two testing sessions which were separated by seven days. In each session, the participants performed three maximal IMTP trials in each of the four testing positions examined, with the order of testing randomized. In each position, no significant differences were found between sessions for all force-time characteristics (p = >0.05). Peak force (PF), time-specific force (F50, F90, F150, F200, F250) and IMP time-bands (0–50, 0–90, 0–150, 0–200, 0–250 ms) were reliable across each of the four testing positions (ICC ≥ 0.7, CV ≤ 15%). Time to peak force, peak RFD, RFD time-bands (0–50, 0–90, 0–150, 0–200, 0–250 ms) and peak IMP were unreliable regardless of the testing position used (ICC = <0.7, CV = >15%). Overall, the use of body postures and barbell positions during the IMTP that do not correspond to the second pull of the clean have no adverse effect on the reliability of the force-time characteristics generated.
Analysis of Research Topics and Scientific Collaborations in Renewable Energy Using Community Detection
Authors: Alcayde Alfredo , G. Montoya Francisco , Baños Raul , Perea-Moreno Alberto-Jesús , Manzano-Agugliaro Francisco
Published: November 2018

Renewable energy is a key breakthrough to mitigate carbon emissions, to reduce global warming, and for the creation of sustainable societies. Renewable energy is a broad area that includes different technologies that are being continuously improved to increase their efficiency and reduce cost. Many papers have been published in the last decades dealing with renewable energy issues, which is why it becomes important to determine the main topics of research, the main publications devoted to publishing scientific papers about renewable energy, and how researchers collaborate in this discipline. With these aims in view, this paper presents an advanced method for analysing publications about renewable energy and scientific collaboration networks in this field. This method is based on automatically obtaining bibliographic data from scientific publications through the use of the Scopus Database API Interface, which are then analysed using community detection algorithms and graph visualization software. The results obtained show that it is possible to determine the main areas of research activity as well as to identify the structures of the collaboration network in the field of renewable energy.
Sustainability of Renewable Off-Grid Technology for Rural Electrification: A Comparative Study Using the IAD Framework
Authors: Lestari Heksi , Arentsen Maarten , Bressers Hans , Gunawan Budhi , Iskandar Johan , Parikesit
Published: November 2018

This paper analyses the implementation of renewable off-grid technologies in rural areas, especially where an extension to the national electricity grid was not considered economically feasible. Implementation of remote, stand-alone, electricity technologies as alternatives to a grid connection to provide sustainable electricity access have often failed with many planned projects not realised or abandoned. Our initial assumption was that stand-alone electricity project exhibiting higher scores on sustainability indicators would benefit communities more and make their endurance more likely. However, the impact of the stand-alone technology was often overruled or its quality weakened by government preferences wishing to realise a connection to the central electricity grid. Empirically, the study compares three cases of stand-alone micro-hydropower projects and three cases of stand-alone solar photovoltaic projects in Bogor Regency, Indonesia. It is based on qualitative document analysis, complemented by multiple rounds of semi-structured interviews and observations. The paper assesses the extent to which each project met indicators of technical, economic, social, environmental, and institutional sustainability. The paper tries to explain the endurance of the project from these sustainability scores and uses additional explanations from Ostrom’s Institutional Analysis and Development (IAD) framework. The findings show that, for the studied local communities, the attractiveness of a grid connection overrules the virtues of a stand-alone electricity project, despite its quality, successful operation and impact. Our research also shows that government policy priorities changed in the rural electrification programme for some communities. In these situations, the off-grid rural electrification programme predominantly provided only temporary access to sustainable electricity for remote local communities that remained waiting and hoping for a grid connection to connect them to fossil fuel-dominated electricity.