bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of Preparation Conditions for Side-Emitting Polymer Optical Fibers Using Response Surface Methodology
Authors: Hu Xianjin , Yang Kun , Zhang Cheng
Published: December 2020

Polymer optical fibers (POFs) were used for preparing side-emitting polymer optical fibers (SPOFs), which were processed with acetone and n-hexane combined in selected proportions by a solvent treatment method. The effects of the volume ratio of acetone to n-hexane and treatment time on response variable factors were investigated. The center composite design (CCD) based response surface methodology (RSM), a quadratic model, and a two-factor interaction model were developed to relate the preparation variables of illumination intensity, breaking strength, and rigidity. According to analysis of variance (ANOVA), the factors affecting the optimization of each response factor were determined. The predicted values after process optimization were found to be highly similar to the experimental values. The optimal conditions for the preparation of SPOF were as follows: the volume ratio of acetone to hexane was 1.703, and the treatment time was 2.716 s. The three response variables of SPOF prepared under the optimal conditions were: illumination intensity 19.339 mV, breaking strength 5.707 N, and rigidity 572.013 N·mm2.
Structural and Dynamical Characteristics of Short-Chain Branched Ring Polymer Melts at Interface under Shear Flow
Authors: Jeong Seung Heum , Cho Soowon , Ha Tae Yong , Roh Eun Jung , Baig Chunggi
Published: December 2020

We present a detailed analysis of the interfacial chain structure and dynamics of confined polymer melt systems under shear over a wide range of flow strengths using atomistic nonequilibrium molecular dynamics simulations, paying particular attention to the rheological influence of the closed-loop ring geometry and short-chain branching. We analyzed the interfacial slip, characteristic molecular mechanisms, and deformed chain conformations in response to the applied flow for linear, ring, short-chain branched (SCB) linear, and SCB ring polyethylene melts. The ring topology generally enlarges the interfacial chain dimension along the neutral direction, enhancing the dynamic friction of interfacial chains moving against the wall in the flow direction. This leads to a relatively smaller degree of slip (ds) for the ring-shaped polymers compared with their linear analogues. Furthermore, short-chain branching generally resulted in more compact and less deformed chain structures via the intrinsically fast random motions of the short branches. The short branches tend to be oriented more perpendicular (i.e., aligned in the neutral direction) than parallel to the backbone, which is mostly aligned in the flow direction, thereby enhancing the dynamic wall friction of the moving interfacial chains toward the flow direction. These features afford a relatively lower ds and less variation in ds in the weak-to-intermediate flow regimes. Accordingly, the interfacial SCB ring system displayed the lowest ds among the studied polymer systems throughout these regimes owing to the synergetic effects of ring geometry and short-chain branching. On the contrary, the structural disturbance exerted by the highly mobile short branches promotes the detachment of interfacial chains from the wall at strong flow fields, which results in steeper increasing behavior of the interfacial slip for the SCB polymers in the strong flow regime compared to the pure linear and ring polymers.
Experimental Study on the Flow and Heat Transfer of Graphene-Based Lubricants in a Horizontal Tube
Authors: Cai Zhongpan , Tian Maocheng , Zhang Guanmin
Published: December 2020

To improve the heat transfer characteristics of lubricant, graphene-based lubricants were prepared by adding graphene particles, due to its advantages of excellent thermal conductivity and two-dimensional sheet structure. In the present study, its physical properties were measured. A flow heat transfer experiment platform was built to study the flow and heat transfer characteristics of the graphene lubricating oil in a horizontal circular tube. The results show that the graphene lubricant prepared using a two-step approach had good stability, and the dispersibility was good without the agglomeration phenomenon, according to measurements undertaken using an electron microscope and centrifuge. The thermal conductivity and viscosity of graphene lubricant increased with the increase of the graphene concentration, and the thermal conductivity of graphene lubricant with the same concentration decreased with the increase of temperature. When the concentration was equal, the convective heat transfer Nusselt number (Nu) of graphene lubricant increased with the increase of Reynolds number (Re). When Re was equal, the convective heat transfer Nu increased with the increase of graphene particle concentration, and the maximum Nu increased by 40%.
VectorDisk: A Microfluidic Platform Integrating Diagnostic Markers for Evidence-Based Mosquito Control
Authors: Hin Sebastian , Baumgartner Desirée , Specht Mara , Lüddecke Jan , Mahmodi Arjmand Ehsan , Johannsen Benita , Schiedel Larissa , Rombach Markus , Paust Nils , von Stetten Felix , Zengerle Roland , Wipf Nadja , Müller Pie , Mavridis Konstantinos , Vontas John , Mitsakakis Konstantinos
Published: December 2020

Effective mosquito monitoring relies on the accurate identification and characterization of the target population. Since this process requires specialist knowledge and equipment that is not widely available, automated field-deployable systems are highly desirable. We present a centrifugal microfluidic cartridge, the VectorDisk, which integrates TaqMan PCR assays in two feasibility studies, aiming to assess multiplexing capability, specificity, and reproducibility in detecting disk-integrated vector-related assays. In the first study, pools of 10 mosquitoes were used as samples. We tested 18 disks with 27 DNA and RNA assays each, using a combination of multiple microfluidic chambers and detection wavelengths (geometric and color multiplexing) to identify mosquito and malaria parasite species as well as insecticide resistance mechanisms. In the second study, purified nucleic acids served as samples to test arboviral and malaria infective mosquito assays. Nine disks were tested with 14 assays each. No false positive results were detected on any of the disks. The coefficient of variation in reproducibility tests was <10%. The modular nature of the platform, the easy adaptation of the primer/probe panels, the cold chain independence, the rapid (2–3 h) analysis, and the assay multiplexing capacity are key features, rendering the VectorDisk a potential candidate for automated vector analysis.
Hydrocracking of Polyethylene to Jet Fuel Range Hydrocarbons over Bifunctional Catalysts Containing Pt- and Al-Modified MCM-48
Authors: Liu Yanyong
Published: December 2020

A low-density polyethylene was hydrocracked to liquid hydrocarbons in autoclave reactors over catalysts containing Pt- and Al-modified MCM-48. Two kinds of Al-modified MCM-48 were synthesized for the reaction: Al-MCM-48 was synthesized using a sol–gel method by mixing Al(iso-OC3H7)3 with Si(OC2H5)4 and surfactant in a basic aqueous solution before hydrothermal synthesis, and Al/MCM-48 was synthesized using a post-modification method by grafting Al3+ ions on the surface of calcined Al/MCM-48. X-ray diffraction (XRD) patterns indicated that both Al-MCM-48 and Al/MCM-48 had a cubic mesoporous structure. The Brunauer–Emmett–Teller (BET) surface areas of Al-MCM-48 and Al/MCM-48 were larger than 1000 m2/g. 27Al Magic Angle Spinning-NMR (MAS NMR) indicated that Al3+ in Al-MCM-48 was located inside the framework of mesoporous silica, but Al3+ in Al/MCM-48 was located outside the framework of mesoporous silica. The results of ammonia temperature-programmed desorption (NH3-TPD) showed that the acidic strength of various samples was in the order of H-Y > Al/MCM-48 > Al-MCM-48 > MCM-48. After 4 MPa H2 was charged in the autoclave at room temperature, 1 wt % Pt/Al/MCM-48 catalyst showed a high yield of C9−C15 jet fuel range hydrocarbons of 85.9% in the hydrocracking of polyethylene at 573 K for 4 h. Compared with the reaction results of Pt/Al/MCM-48, the yield of light hydrocarbons (C1−C8) increased over Pt/H-Y, and the yield of heavy hydrocarbons (C16−C21) increased over Pt/Al-MCM-48 in the hydrocracking of polyethylene. The yield of C9−C15 jet fuel range hydrocarbons over the used catalyst did not decrease compared to the fresh catalyst in the hydrocracking of polyethylene to jet fuel range hydrocarbons over Pt/Al/MCM-48.
Ocean Real-Time Precise Point Positioning with the BeiDou Short-Message Service
Authors: He Kaifei , Weng Duojie , Ji Shengyue , Wang Zhenjie , Chen Wu , Lu Yangwei
Published: December 2020

Real-time precise point positioning (RTPPP) is a popular positioning method that uses a real-time service (RTS) product to mitigate various Global Navigation Satellite Systems (GNSS) errors. However, communication links are not available in the ocean. The use of a communication satellite for data transmission is so expensive that normal users could not afford it. The BeiDou short-message service provides an efficient option for data transmission at sea, with an annual fee of approximately 160 USD. To perform RTPPP using BeiDou short messages, the following two challenges should be appropriately addressed: the maximum size of each BeiDou message is 78 bytes, and the communication frequency is limited to once a minute. We simplify the content of RTS data to minimize the required bandwidth. Moreover, the orbit and clock corrections are predicted based on minute-interval RTS orbital and clock corrections. An experiment was conducted to test the performance of the proposed method. The numerical results show that the three-dimensional positioning precision can reach approximately 0.4 m with combined GPS + GLONASS and approximately 0.2 m with combined GPS + GLONASS + Galileo + BeiDou.
Exploring the Fingerprints of Past Rain-on-Snow Events in a Central Andean Mountain Range Basin Using Satellite Imagery
Authors: Ocampo Melgar D. , Meza F.J.
Published: December 2020

Rain-on-snow (ROS) events can alter nival regimes and increase snowmelt, peak river flow, and reduce water storage. However, detection of ROS events is challenging and only the most intense and obvious cases are identified. Rain is known to reduce snow cover and decrease near-infrared reflectance due to increased grain size. This study explored the fingerprints of ROS events on mountain snowpack with a simple typology that classifies changes in snow reflectance using fifteen years of MODIS imagery, reanalysis, and surface hydrometeorological data. The Maipo River Basin, with strong nival regime and a steep topography, in the western Andean mountain range was selected as a case study. Statistical analysis showed two distinct and opposite responses in the near infrared reflectance distribution of snow-covered pixels after precipitation, consistent with the typology for rain or snow events. For the probable ROS events, the daily maximum and minimum temperature increased in the days preceding the event and subsequently decreased, in some cases followed by a less consistent response in river flow. Although much remains to be studied, this approach can be used to expand historical records and improve modelling and detection schemes.
Spatio-Temporal Characteristics of Drought Events and Their Effects on Vegetation: A Case Study in Southern Tibet, China
Authors: Ye Zu-Xin , Cheng Wei-Ming , Zhao Zhi-Qi , Guo Jian-Yang , Yang Ze-Xian , Wang Rui-Bo , Wang Nan
Published: December 2020

Frequent droughts in a warming climate tend to induce the degeneration of vegetation. Quantifying the response of vegetation to variations in drought events is therefore crucial for evaluating the potential impacts of climate change on ecosystems. In this study, the standardized precipitation index (SPI) was calculated using the precipitation data sourced from the China Meteorological Forcing Dataset (CMFD), and then the drought events in southern Tibet from 1982 to 2015 were identified based on the SPI index. The results showed that the frequency, severity, and intensity of drought events in southern Tibet decreased from 1982 to 2015, and the highest frequency of drought was found between 1993 and 2000. To evaluate the impact of drought events on vegetation, the vegetation characteristic indexes were developed based on the normalized difference vegetation index (NDVI) and the drought characteristics. The assessment of two drought events showed that the alpine grasslands and alpine meadows had high vegetation vulnerability (AI). The assessment of multiple drought events showed that responses of vegetation to drought were spatially heterogeneous, and the total explain rate of environmental factors to the variations in AI accounted for 40%. Among the many environmental factors investigated, the AI were higher at middle altitudes (2000–3000 m) than low altitudes (<2000 m) and high altitudes (3000–4500 m). Meanwhile, the silt soil fraction in the upper soil layer (0–30 cm) had the greatest positive correlation with AI, suggesting that areas with a high silt soil fraction were more sensitive to drought. The relative contribution rates of environmental factors were predicted by a multivariate linear regression (MLR) model. The silt soil fraction was found to make the greatest relative contribution (23.3%) to the changes in AI.
A Quantile Approach for Retrieving the “Core Urban-Suburban-Rural” (USR) Structure Based on Nighttime Light
Authors: Huang Yaohuan , Wu Chengbin , Chen Mingxing , Yang Jie , Ren Hongyan
Published: December 2020

Accurate and timely information on the “core urban-suburban-rural” (USR) spatial structure in a metropolitan region is significant for both the scientific and policy-making communities. However, USR is usually considered as a single land use type, such as an impervious area, rather than three combined subcategories in remote-sensing image retrieval, especially for suburban areas, which obscures the details of the urbanization process. In this paper, we propose a quantile approach to retrieve the structure of USR based on stable nighttime light (NTL) data from the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) and apply it in the Beijing-Tianjin-Hebei (JJJ) of China from 1995 to 2013. The key parameters of the NTL threshold, which is the maximum change point of the NTL intensity at the USR boundary, used to retrieve the three subcategories of USR are automatically defined based on the quantile approach with three iterations. Then, the overall accuracy and consistency of the retrieval results are evaluated using the corresponding visual interpretation map from Landsat images with a 30 m resolution. Moreover, the influence of parameter uncertainty is compared by introducing the human settlement index (HSI). According to the time-series analysis of USR retrieval in this study, the JJJ experienced rapid urbanization from 1995 to 2013, with the core urban area expanding by 7098 km2 (average increase of 2.7 times), the suburban area expanding by 12,690 km2 (average increase of 2.8 times), and the rural area increasing by 4986 km2 (average increase of 0.38 times). The USR results retrieved based on the approach agree well with the validation of the visual interpretation map, with an overall accuracy (OA) of 0.904 and a kappa coefficient (KC) of 0.650 at the city level. The USR result with the HSI as the input shows that NTL is more suitable for USR structure retrieval as the NTL shows less uncertainty compared with other parameters such as the vegetation index (VI). This study proposes an improved quantile approach for USR mapping from NTL images on a regional scale, which will provide a useful method for urbanization dynamics analysis.
Life Cycle Environmental and Economic Performance Analysis of Bagasse-Based Electricity in Pakistan
Authors: Ghani Hafiz Usman , Mahmood Awais , Ullah Asmat , Gheewala Shabbir H.
Published: December 2020

Bagasse-based electricity is gaining attention as an affordable, reliable, sustainable, and promising renewable energy source in Pakistan. Therefore, the focus of this analysis was to identify the environmental burdens associated with bagasse-based electricity production via high-pressure cogeneration. The scope of this study was defined as cradle to gate; involving cane production, cane transportation to the mill, the production of bagasse, and then the burning of bagasse in the cogeneration power plant to produce electricity. The overall results revealed that most of the impacts were contributed by the agricultural phase. For some impact categories—such as global warming, fine particulate matter formation, terrestrial acidification, and fossil resource scarcity—the bagasse-based electricity performed better than the grid mix electricity. However, the grid mix electricity performed better than the bagasse-based electricity in terms of eutrophication, land use, and water consumption. When considering the final damage, the bagasse-based electricity proved to be the favorable option in terms of human health and resource availability; however, ecosystem quality was poor in bagasse-based electricity. In terms of environmental prices, the bagasse-based electricity was found to be a promising option compared to the grid mix electricity.
A Review of Control Techniques in Photovoltaic Systems
Authors: Murillo-Yarce Duberney , Alarcón-Alarcón José , Rivera Marco , Restrepo Carlos , Muñoz Javier , Baier Carlos , Wheeler Patrick
Published: December 2020

Complex control structures are required for the operation of photovoltaic electrical energy systems. In this paper, a general review of the controllers used for photovoltaic systems is presented. This review is based on the most recent papers presented in the literature. The control architectures considered are complex hybrid systems that combine classical and modern techniques, such as artificial intelligence and statistical models. The main contribution of this paper is the synthesis of a generalized control structure and the identification of the latest trends. The main findings are summarized in the development of increasingly robust controllers for operation with improved efficiency, power quality, stability, safety, and economics.
Review and Development of a Land Consumption Evaluation Method Based on the Time-Area Concept of Last Mile Delivery Using Real Delivery Trip Data
Authors: Schnieder Maren , Hinde Chris , West Andrew
Published: December 2020

The paper proposes an evaluation method providing decision support for policymakers in regard to the land consumption of transport activities. Due to the increasing pressure on vehicle parking, traffic jams and the housing crisis in large cities, it is important to use road space effectively. The primary objective of this paper is to review and evaluate the published research about the time-area concept, as well as proposing an evaluation method for the time-area requirements of vehicles used in last mile delivery such as pedestrian porters, bicycles, cargo bikes, sidewalk autonomous delivery robots (SADRs) and delivery vans. The time-area concept measures the size of an area occupied during a transport activity and the duration for which it is occupied for standing, as well as moving transport units. While most of the research applies the time-area concept to compare various modes of transport used to move people around a city, this paper focusses on moving parcels and evaluates the effect that operating strategies and policy changes have on the time-area requirements of a single mode of transport. The study builds on a real trip data set of parcel deliveries in London.
Discussing the Use of Complexity Theory in Engineering Management: Implications for Sustainability
Authors: Abatecola Gianpaolo , Surace Alberto
Published: December 2020

What is the state-of-the-art literature regarding the adoption of the complexity theory (CT) in engineering management (EM)? What implications can be derived for future research and practices concerning sustainability issues? In this conceptual article, we critically discuss the current status of complexity research in EM. In this regard, we use IEEE Transactions on Engineering Management, because it is currently considered the leading journal in EM, and is as a reliable, heuristic proxy. From this journal, we analyze 38 representative publications on the topic published since 2000, and extrapolated through a rigorous keyword-based article search. In particular, we show that: (1) the adoption of CT has been associated with a wide range of key themes in EM, such as new product development, supply chain, and project management. (2) The adoption of CT has been witnessed in an increasing amount of publications, with a focus on conceptual modeling based on fuzzy logics, stochastic, or agent-based modeling prevailing. (3) Many key features of CT seem to be quite clearly observable in our dataset, with modeling and optimizing decision making, under uncertainty, as the dominant theme. However, only a limited number of studies appear to formally adhere to CT, to explain the different EM issues investigated. Thus, we derive various implications for EM research (concerning the research in and practice on sustainability issues).
Social Entrepreneurship: The Logic of Paradox
Authors: Weller Scott , Ran Bing
Published: December 2020

Social entrepreneurship is a paradoxical phenomenon wherein seemingly incompatible elements such as business and social logics coexist. Previous research has been insufficient to systematically describe how social entrepreneurship organizations (SEO) try to balance these logics and why these same paradoxical elements make social entrepreneurship what it is. Using the systematic literature review method, this paper examines six major paradoxes and how they affect both the theory and practice of social entrepreneurship by furthering the nascent discussion about the role of paradoxes in SEOs. Viewed through the lens of organizational logics, this paper argues that the dynamic interplay between these paradoxes initiates and drives the innovations and changes necessary for the very existence of SEOs.
Sustainable Business Model Based on Open Innovation: Case Study of Iberdrola
Authors: Alvarez-Meaza Izaskun , Pikatza-Gorrotxategi Naiara , Rio-Belver Rosa Maria
Published: December 2020

The change in business management towards a vision based on open innovation has opened the doors to knowledge transfer between organizations, promoting scientific–technological collaborations resulting in new research that opens the way to new technological innovations. Therefore, the objective of this study is to see how the company Iberdrola has oriented its management strategy towards an open innovation approach, analyzing both its scientific and technological development through a bibliometric and network analysis. The results highlight that Iberdrola has always considered scientific and technological development to be part of its strategic approach as a means of disseminating and transferring knowledge. Furthermore, it can be concluded that the implementation of strategic axes related to sustainable development in an open innovation environment has improved the results of its scientific and technical production, and also the company’s financial results.
Glycinebetaine-Induced Alteration in Gaseous Exchange Capacity and Osmoprotective Phenomena in Safflower (Carthamus tinctorius L.) under Water Deficit Conditions
Authors: Nazar Zanib , Akram Nudrat Aisha , Saleem Muhammad Hamzah , Ashraf Muhammad , Ahmed Shakeel , Ali Shafaqat , Abdullah Alsahli Abdulaziz , Alyemeni Mohammed Nasser
Published: December 2020

Several inorganic and organic compounds including glycine betaine (GB) are presently being used as an exogenous application to enhance tolerance in plants to different environmental stresses. The current study assessed to what extent exogenously applied GB could improve the gaseous exchange capacity and primary and secondary metabolites in two accessions (16178 and 16180) of safflower (Carthamus tinctorius L.) plants under drought stress. Three-week-old plants of both safflower accessions were subjected to well-watered (control) or water-deficit conditions (60% field capacity (FC)). Three levels of GB (control, 50 mM and 100 mM) were sprayed to the foliage of the control and stressed plants after one month of drought application. After two weeks of foliar application of GB, gas exchange characteristics and other biochemical parameters were determined. The results showed that water deficiency markedly suppressed plant biomass, chlorophyll contents, photosynthesis rate (A), water use efficiency (A/E), stomatal conductance (gs) and relative water contents (RWC) of both accessions of safflower, while it enhanced the levels of osmolytes (GB and proline), hydrogen peroxide (H2O2) and total phenolics. Foliar application of GB was effective in enhancing the plant biomass, chlorophyll contents, gs, sub-stomatal CO2 concentration (Ci), Ci/Ca ratio, osmolytes, H2O2, ascorbic acid (AsA), total phenolics and RWC in safflower plants under water shortage. Thus, exogenous application of GB could be used as an effective strategy to improve plant growth, photosynthetic attributes and secondary metabolites in safflower plants under water deficit conditions.
A Pilot Experiment to Develop a Lightweight Non-Nuclear EMP Shelter Applying Civil-Military Cooperation in a Sustainability Policy
Authors: Kim Kukjoo , Min Kyung-Ryeung , Park Young-Jun
Published: December 2020

The goal of future wars is to incapacitate national core infrastructures through cyberattacks and electronic wars. The use of high-tech arms including high-power electronic weapons, laser weapons, and railguns to achieve a precise strike, minimum cost, and neutralization is gradually increasing. Considering the nuclear provocation and non-nuclear electromagnetic pulse (NNEMP) threats from North Korea, it has become urgent for Korea to expand its EMP protection systems. Hence, the need for developing a protective technology lighter than the conventional EMP protection technology is continuously being raised. However, no facility has applied such a lightweight protection technology thus far. Thus, this study tests the performance of a lightweight electromagnetic (EM) shielding material and evaluates the possibility of building a lightweight NNEMP shelter by installing the material. Among the commercially available EM shielding materials, only those appropriate for lightweight purpose are selected. Accordingly, the EM shielding performances of nine fabric types, five film types, and four wallpaper types are tested. For testing, a pan-type EM shielding room 2.5 m × 3.0 m × 2.5 m was constructed with a shielding performance of 80 dB at 18 GHz. The measurement method was based on the IEEE-STD-299 standard, and 10 frequencies from 14 kHz to 18 GHz were used. The result showed that the shielding performance was the highest in the 100 MHz band in most cases. In the high-frequency band above 1 GHz, the shielding performance was almost equal to, or slightly lower than, that in the 100 MHz band. This study confirms the feasibility of building lightweight NNEMP shelters in major military and civil facilities. If the NNEMP shelters to be constructed in military and civil facilities are replaced with lightweight shelters, approximately 49,862.4 tons of CO2 emissions due to the concrete saved can be reduced per shelter. Assuming the Korean carbon transaction price to be USD 50/ton-CO2, the saving amounts to US $2,493,120, contributing to the green growth policy of Korea.
RETRACTED: Paving towards Strategic Investment Decision: A SWOT Analysis of Renewable Energy in Bangladesh
Authors: Karim Ridoan , Muhammad-Sukki Firdaus , Hemmati Mina , Newaz Md , Farooq Haroon , Muhtazaruddin Mohd , Zulkipli Muhammad , Ardila-Rey Jorge
Published: December 2020

Bangladesh, being a developing country, needs an uninterrupted electricity supply to sustain and expand economic growth. The government’s strategic vision of 2021 and the international commitment under the Paris Agreement has meant to attract new capital investments for renewable electricity generation by diversifying energy blends, ranging from natural gas to more reliable coal technologies and renewable energy. To understand the practical implementation of such policies, this paper explores the key factors of the renewable energy (RE) sector of Bangladesh. This research has adopted the strengths, weaknesses, opportunities, and threats (SWOT) analysis method to examine the RE market and to understand the determinants of foreign direct investment (FDI) to attract new investments. For the analysis purposes, data were collected from extant literature and semi-structured interviews from the RE experts in Bangladesh. This study bears significance as it empirically reflects the government’s vision and strategy on RE development and analyzes its challenges and recommends accordingly. The analysis of the study reveals that the regulatory framework, tax haven/exemption, higher tariff, and presence of government guarantee are the major strengths to draw foreign investment. On the contrary, land acquisition, lack of coordination and collaboration among government authorities, administrative procedures, corruption, and access to local finance turns out to be the key weaknesses to consider while investing in this sector. In terms of the external factors, increasing energy demand, increasing global awareness of climate change, and decreasing cost of RE setup equipment act as potent opportunities; while the dominance of fossil fuel and discontinuity of energy policies should be taken as threats that can hinder the flow of investment in this sector. Hence, in order to attract sustainable FDI in the RE sector, several key areas need to be strengthened in the short, medium, and long-term. These are: (i) regulations on non-discriminatory treatment to foreign investors; (ii) control of corruption; (iii) protection of intellectual property rights; and (iv) coordination and collaboration between ministries.
Smart Mobility: The Main Drivers for Increasing the Intelligence of Urban Mobility
Authors: Maldonado Silveira Alonso Munhoz Paulo Antonio , da Costa Dias Fabricio , Kowal Chinelli Christine , Azevedo Guedes André Luis , Neves dos Santos João Alberto , da Silveira e Silva Wainer , Pereira Soares Carlos Alberto
Published: December 2020

Urban mobility plays a key role in the ecosystems of complex smart cities. It is considered a key factor in enabling cities to become more intelligent, which highlights the importance of identifying the drivers that improve the intelligence of cities. In this study, we investigate the main drivers with the potential to increase urban mobility intelligence and assign them a priority. Following on from a systematic review of the literature, we conducted broad and detailed bibliographic research based on the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). We also surveyed 181 professionals working in the field concerned to confirm the importance of different drivers and assign them a level of priority. The results show that 27 drivers identified in the literature were considered important, of which seven, related to city governance and technical solutions, were considered the most important to increase urban mobility intelligence.
Recent Progress on the Development of Engineered Silica Particles Derived from Rice Husk
Authors: Chun Jinyoung , Lee Jin Hyung
Published: December 2020

The development of engineered silica particles by using low-cost renewable or waste resources is a key example of sustainability. Rice husks have emerged as a renewable resource for the production of engineered silica particles as well as bioenergy. This review presents a state-of-the-art process for the development of engineered silica particles from rice husks via a bottom-up process. The first part of this review focuses on the extraction of Si from rice husks through combustion and chemical reactions. The second part details the technologies for synthesizing engineered silica particles using silicate obtained from rice husks. These include technologies for the precipitation of silica particles, the control of morphological properties, and the synthesis of ordered porous silica particles. Finally, several issues that need to be resolved before this process can be commercialized are addressed for future research.
Life Cycle Environmental Assessment of Light Steel Framed Buildings with Cement-Based Walls and Floors
Authors: Abouhamad Mona , Abu-Hamd Metwally
Published: December 2020

The objective of this paper is to apply the life cycle assessment methodology to assess the environmental impacts of light steel framed buildings fabricated from cold formed steel (CFS) sections. The assessment covers all phases over the life span of the building from material production, construction, use, and the end of building life, in addition to loads and benefits from reuse/recycling after building disposal. The life cycle inventory and environmental impact indicators are estimated using the Athena Impact Estimator for Buildings. The input data related to the building materials used are extracted from a building information model of the building while the operating energy in the use phase is calculated using an energy simulation software. The Athena Impact Estimator calculates the following mid-point environmental measures: global warming potential (GWP), acidification potential, human health potential, ozone depletion potential, smog potential, eutrophication potential, primary and non-renewable energy (PE) consumption, and fossil fuel consumption. The LCA assessment was applied to a case study of a university building. Results of the case study related to GWP and PE were as follows. The building foundations were responsible for 29% of the embodied GWP and 20% of the embodied PE, while the CFS skeleton was responsible for 30% of the embodied GWP and 49% of the embodied PE. The production stage was responsible for 90% of the embodied GWP and embodied PE. When benefits associated with recycling/reuse were included in the analysis according to Module D of EN 15978, the embodied GWP was reduced by 15.4% while the embodied PE was reduced by 6.22%. Compared with conventional construction systems, the CFS framing systems had much lower embodied GWP and PE.
Distribution Function, Probability Generating Function and Archimedean Generator
Authors: Alhadlaq Weaam , Alzaid Abdulhamid
Published: December 2020

Archimedean copulas form a very wide subclass of symmetric copulas. Most of the popular copulas are members of the Archimedean copulas. These copulas are obtained using real functions known as Archimedean generators. In this paper, we observe that under certain conditions the cumulative distribution functions on (0, 1) and probability generating functions can be used as Archimedean generators. It is shown that most of the well-known Archimedean copulas can be generated using such distributions. Further, we introduced new Archimedean copulas.
An Authorship Protection Technology for Electronic Documents Based on Image Watermarking
Authors: Melman Anna , Evsutin Oleg , Shelupanov Alexander
Published: December 2020

In the field of information technology, information security technologies hold a special place. They ensure the security of the use of information technology. One of the urgent tasks is the protection of electronic documents during their transfer in information systems, including smart systems. This paper proposes a technology for protecting electronic documents containing digital images. The main idea is that the electronic document authorship can be protected by embedding digital watermarks in the images that are contained in this document. The paper considers three cases of using the proposed technology: full copying of an electronic document, copying of images contained in the document, and copying of text. It is shown that in all three cases, the authorship confirmation can be successfully implemented. Some areas of the proposed technology application are described, including augmented reality applications. Computational experiments are conducted with robust watermarking algorithms that can be used within the technology. A scenario of technology implementation is proposed which provides for the joint use of different class algorithms.
The Confounder-Mediator Dilemma: Should We Control for Obesity to Estimate the Effect of Perfluoroalkyl Substances on Health Outcomes?
Authors: Inoue Kosuke , Goto Atsushi , Sugiyama Takehiro , Ramlau-Hansen Cecilia Høst , Liew Zeyan
Published: December 2020

Confounding adjustment is important for observational studies to derive valid effect estimates for inference. Despite the theoretical advancement of confounding selection procedure, it is often challenging to distinguish between confounders and mediators due to the lack of information about the time-ordering and latency of each variable in the data. This is also the case for the studies of perfluoroalkyl substances (PFAS), a group of synthetic chemicals used in industry and consumer products that are persistent and have endocrine-disrupting properties on health outcomes. In this article, we used directed acyclic graphs to describe potential biases introduced by adjusting for or stratifying by the measure of obesity as an intermediate variable in PFAS exposure analyses. We compared results with or without adjusting for body mass index in two cross-sectional data analyses: (1) PFAS levels and maternal thyroid function during early pregnancy using the Danish National Birth Cohort and (2) PFAS levels and cardiovascular disease in adults using the National Health and Nutrition Examination Survey. In these examples, we showed that the potential heterogeneity observed in stratified analyses by overweight or obese status needs to be interpreted cautiously considering collider stratification bias. This article highlights the complexity of seemingly simple adjustment or stratification analyses, and the need for careful consideration of the confounding and/or mediating role of obesity in PFAS studies.
Comparison of the Zebrafish Embryo Toxicity Assay and the General and Behavioral Embryo Toxicity Assay as New Approach Methods for Chemical Screening
Authors: Achenbach John C. , Leggiadro Cindy , Sperker Sandra A. , Woodland Cindy , Ellis Lee D.
Published: December 2020

The movement away from mammalian testing of potential toxicants and new chemical entities has primarily led to cell line testing and protein-based assays. However, these assays may not yet be sufficient to properly characterize the toxic potential of a chemical. The zebrafish embryo model is widely recognized as a potential new approach method for chemical testing that may provide a bridge between cell and protein-based assays and mammalian testing. The Zebrafish Embryo Toxicity (ZET) model is increasingly recognized as a valuable toxicity testing platform. The ZET assay focuses on the early stages of embryo development and is considered a more humane model compared to adult zebrafish testing. A complementary model has been developed that exposes larvae to toxicants at a later time point during development where body patterning has already been established. Here we compare the toxicity profiles of 20 compounds for this General and Behavioral Toxicity (GBT) assay to the ZET assay. The results show partially overlapping toxicity profiles along with unique information provided by each assay. It appears from this work that these two assays applied together can strengthen the use of zebrafish embryos/larvae as standard toxicity testing models.
The RNA Architecture of the SARS-CoV-2 3′-Untranslated Region
Authors: Zhao Junxing , Qiu Jianming , Aryal Sadikshya , Hackett Jennifer , Wang Jingxin
Published: December 2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the current COVID-19 pandemic. The 3′ untranslated region (UTR) of this β-CoV contains essential cis-acting RNA elements for the viral genome transcription and replication. These elements include an equilibrium between an extended bulged stem-loop (BSL) and a pseudoknot. The existence of such an equilibrium is supported by reverse genetic studies and phylogenetic covariation analysis and is further proposed as a molecular switch essential for the control of the viral RNA polymerase binding. Here, we report the SARS-CoV-2 3′ UTR structures in cells that transcribe the viral UTRs harbored in a minigene plasmid and isolated infectious virions using a chemical probing technique, namely dimethyl sulfate (DMS)-mutational profiling with sequencing (MaPseq). Interestingly, the putative pseudoknotted conformation was not observed, indicating that its abundance in our systems is low in the absence of the viral nonstructural proteins (nsps). Similarly, our results also suggest that another functional cis-acting element, the three-helix junction, cannot stably form. The overall architectures of the viral 3′ UTRs in the infectious virions and the minigene-transfected cells are almost identical.
SARS-CoV-2 Seroprevalence Survey in People Involved in Different Essential Activities during the General Lock-Down Phase in the Province of Prato (Tuscany, Italy)
Authors: Lastrucci Vieri , Lorini Chiara , Del Riccio Marco , Gori Eleonora , Chiesi Fabrizio , Sartor Gino , Zanella Beatrice , Boccalini Sara , Bechini Angela , Puggelli Francesco , Bonanni Paolo , Bonaccorsi Guglielmo
Published: December 2020

Serosurveys may help to assess the transmission dynamics in high-risk groups. The aim of the study was to assess the SARS-CoV-2 antibody seroprevalence in people who had performed essential activities during the lock-down period in the Province of Prato (Italy), and to evaluate the risk of exposure to SARS-CoV-2 according to the type of service. All the workers and volunteers of the Civil Protection, employees of the municipalities, and all the staff of the Health Authority of the Province of Prato were invited to be tested with a rapid serological test. A total of 4656 participants were tested. SARS-CoV-2 antibodies were found in 138 (2.96%) cases. The seroprevalence in health care workers, in participants involved in essential support services and in those who worked from home were 4.1%, 1.4% and 1.0%, respectively. Health care workers experienced higher odds of seropositivity (OR 4.38, 95%CI 2.19–10.41) than participants who were assigned to work-from-home; no significant seropositivity differences were observed between support services and work-from-home groups. A low circulation of SARS-CoV-2 was observed among participants performing different essential activities. Findings highlighted the risk of in-hospital transmission in healthcare workers and that community support services may increase the risk of seropositivity to a limited extent in low incidence areas.
Modelling of Flood Inundation due to Levee Breaches: Sensitivity of Flood Inundation against Breach Process Parameters
Authors: Tadesse Yohannis Birhanu , Fröhle Peter
Published: December 2020

This paper analyses the sensitivity of flood inundation due to river levee breach against breach process parameters using the 1996 Awash River levee breach case at Wonji, Ethiopia. A parametric levee breach model integrated into the 2D hydrodynamic numerical model Telemac-2D is used to simulate a levee breach flood event at Wonji, Ethiopia. Levee breach process parameters are systemically varied to find out their effect on the flood inundation. The analysis of the model results shows that the flood inundation is sensitive to the final breach dimensions and breach location. However, the parameters describing the levee breach development have negligible influence on the flood inundation. This implies that final breach dimension and breach location in an event of levee breach are the most important and decisive parameters affecting the resulting inundation of the flood plain, and as such should be given due consideration when creating flood inundation maps due to levee breach.
Removal of Diclofenac in Wastewater Using Biosorption and Advanced Oxidation Techniques: Comparative Results
Authors: Angosto José M. , Roca María J. , Fernández-López José A.
Published: December 2020

Wastewater treatment is a topic of primary interest with regard to the environment. Diclofenac is a common analgesic drug often detected in wastewater and surface water. In this paper, three commonly available agrifood waste types (artichoke agrowaste, olive-mill residues, and citrus waste) were reused as sorbents of diclofenac present in aqueous effluents. Citrus-waste biomass for a dose of 2 g·L−1 allowed for removing 99.7% of diclofenac present in the initial sample, with a sorption capacity of 9 mg of adsorbed diclofenac for each gram of used biomass. The respective values obtained for olive-mill residues and artichoke agrowaste were around 4.15 mg·g−1. Advanced oxidation processes with UV/H2O2 and UV/HOCl were shown to be effective treatments for the elimination of diclofenac. A significant reduction in chemical oxygen demand (COD; 40–48%) was also achieved with these oxidation treatments. Despite the lesser effectiveness of the sorption process, it should be considered that the reuse and valorization of these lignocellulosic agrifood residues would facilitate the fostering of a circular economy.
An Application of Correlation and Spectral Analysis in Hydrological Study of Neighboring Karst Springs
Authors: Denić-Jukić Vesna , Lozić Ana , Jukić Damir
Published: December 2020

Various methods of time series analysis have been used in studies of karst hydrological systems. Among these methods, correlation and spectral analysis have had an important role. The correlation analysis most often has been based on determination of correlation coefficients and correlation functions. Partial correlation functions (PCF) are a mathematical tool of the correlation analysis which practical applicability in karst hydrology is insufficiently explored. In this study, the correlation and spectral analysis are applied on the catchment of Rumin Springs located in the Dinaric karst area between Croatia and Bosnia and Herzegovina. The available daily data are the rainfall, air temperature and relative humidity from three locations, as well as the discharge from two springs. The periods before and after the construction of HPP Orlovac in 1973 are analyzed. The basic hypothesis is that a difference between PCF obtained for two neighboring karst springs describe a difference in their functioning. The results of application show that PCF can resolve some ambiguities concerning the effects included in correlation functions and can provide the additional information that cannot be obtained by other methods of time series analysis. The obtained results are mostly in accordance with the present knowledge, and they support the existing hypotheses about the functioning of Rumin Springs.