bluuebunny/crossref_metadata_2025 huggingface dataset:
C1 C2- symmetric operators for some types of operators
Authors: Dakheel Shireen O. , Ahmed Buthainah A.
Published: August 2022

In this paper, we give some new properties of C1C2-symmetric operators and discuss some results about these kind of operators. Also, we describe the conditions that a binormal operator becomes normal operator and give necessary and sufficient conditions that C1C2- symmetric operators becomes a binormal operator. Finally, we solve the problem that a binormal operator is not closed under addition.
Fabrication of polymer nanocomposite (PbO and W2O3) for gamma-ray attenuations
Authors: Jabbar Rashid Hashim , Hilal Israa Hadi , Ebrahiem Sameera Ahmed , Abdulsattar Mudar Ahmed , Mutter Mahdi M. , Hashim Sarah Rashid
Published: August 2022

(PbO and W2O3) nanocomposite has been prepared by adding a fixed ratio of PbO nanoparticles about (0.05) wt.% with different concentrations of W2O3 (0.05, 0.1, 0.15, 0.2, 0.25) wt.% with epoxy 405.thickness of samples is 0.3 cm to use as a protective shield of gamma-ray, structural properties of the samples have been studied by X-ray diffraction (XRD), Atom Force Microscope (AFM), and Nuclear Magnetic Resonance (NMR). Gamma-ray is reduced with the increasing of the (PbO and W2O3) concentrations caused by the increasing linear attenuation coefficient.
Physical Properties of PVA:PVP blend reinforced by MWCNT
Authors: Mahmood Hanaa S. , Habubi Nadir F.
Published: August 2022

The polyvinyl alcohol (PVA), Polyvinylpyrrolidone (PVP), PVA-PVP blend, and reinforced-sample with multi-walled carbon nanotubes (MWCNTs) were prepared in different proportions by casting technique. X-ray diffraction testing denotes a blending of copolymers and the added CNTs. The FE-SEM images illustrate rubber-like entangled of pure PVA-PVP blend. The MWCNTs of 1% ratio completely imbedded within the polymer and the blend appeared higher compact. The stress-strain curves for PVA-PVP blend sample and samples reinforced with CNTs show that the sample stiffness increased, where the elongation reduced when the carbon nanotube added increased to 1.5 wt% due to the contribution of binding to the added MWCNTs which limits the flexibility of the sample. The sample delivery behaviour greatly affected the charge carriers hopping over the barriers between neighbouring localized states. Increasing the MWCNT contents leads to an increase in the AC conductivity due to the creation of more localized states or by reducing the potential barriers. The dielectric constant (ε1) of the PVA-PVP blend samples decreased with increasing frequency until it reached quasi-constant at higher frequencies. The dielectric constant also decreased with the increase of the carbon nanotube contents. The dielectric loss (ε2) also decreases with frequency. These results demonstrated that the conductivity and dielectric parameters of the copolymer samples strongly depend on frequency and are significantly affected by the proportion of the added MWCNTs.
Production of bioactive MgO nanoparticles via anodic technique
Authors: Abbas M K , Sh Hashim M
Published: August 2022

MgO nanoparticles (MgONps) were prepared by the rapid anodizing method (RBA). The properties of these particles were tested by X-ray diffraction (XRD) and Scanning electron microscope (SEM). MgO powder had a polycrystalline structure with a dominant peak (200). MgONps had a spherical shape with a diameter of ~ 30 nm. To test the ability of this material to stimulate bone like apatite, these particles were deposited on a Ti base by electrophoretic deposition (EPD) method and then dipped in simulated body fluid (SBF) for one month. The formation of hydroxyapatite (HAp) on MgONps after 30 days was proved through the appearance of several HAp peaks in the XRD pattern of the sample. SEM images showed that HAp was in the form of nanoballs connected to each other. According to the Energy dispersive X-ray spectroscopy (EDX) test wt% for Ca and P were 32.8 and 23.3 respectively.
Foreign Object Debris Material Recognition based on Ensemble Learning Algorithm
Authors: Shaker Dina R , Abbas Ayad R
Published: August 2022

The material characteristics of foreign Object Debris (FOD) are the essential criteria in determining the extent of an aircraft’s damage. Foreign object debris (FOD) can cause significant accidents and financial losses on airport runways. A new FOD material recognition strategy is proposed in this paper using an ensemble learning algorithm, namely KNN, Adaboost, and Random Forest Tree, to classify FOD images. In addition, this study uses different feature extraction methods like Linear Discriminant Analysis (LDA) and Gray-level co-occurrence matrix(GLCM) to extract FOD features. The KNN, Adaboost, and Random Forest Tree precision are 94.20%, 98.9%, and 99.7%, respectively. The dataset that was used has been collected by researchers from several datasets. As a result, the experiment results reveal that the proposed framework is effective and accurate. The results showed that the best classification machine algorithm is Random Forest Tree.
Fusion of DWT as a Novel Approach for Efficient, Secured and Reversible Video Steganography
Authors: Tuieb Munthir Bahir , Mahmood Ali Shakir , Abbas Farah Neamah
Published: August 2022

This research is inspired by the constraints of the present video steganography methods and to enhance their performance. It contributes its objective via employing the transforming steps to involve the processing of both cover videos and clandestine information for improving their robustness and security. Consuming a part of every frame as areas of concentration for the hiding procedure, this leads to improve the video imperceptibility resulted from steganography. In view of that, selecting the coefficients for embedding information in the video. Subsequently it adds obstacle in front of intruders to identify the place of the hidden information within frames since they are just covered within such coefficients, this dynamically changes depending on both the video frame and clandestine information, it is essential to save the embedding robustness and security. Converting the cover into a frequency domain like DWT will enhance the steganographic robustness counter to threats.
Effect of CNFs-Ni/LDPE electrode on space charge injection in LDPE insulating layer
Authors: Xing Zhaoliang , Hu Xiangnan , Liu Yujia , Hao Ming , Zhang Chong , Hao Chuncheng , Lei Qingquan
Published: August 2022

The accumulation of space charge is considered to be an important key factor to accelerate the aging of the insulation of HVDC cables. How to reduce the accumulation of space charge in the insulation layer is an urgent problem to improve the voltage level of cables. In this paper, an approach is presented to prevent charge from the inner semiconductive layer to the insulating layer, using a modified semiconductive compound by doping magnetic carbon nanofibers. Through microwave-assisted heating, Ni was deposited on the surface of carbon nanofibers which have been pre-treated. Modified semiconductive compound electrodes was used to test the injection of charges. The results showed that charge injected into LDPE insulting layerwith modified CNFs-Ni/ LDPE electrode is less than that with LDPE semiconductive layer without CNFs-Ni electrode.
A 13 Gbps 1:16 deserializer ASIC for NICA multi purpose detector project
Authors: Chen Q. , Guo D. , Zhao C. , Guo Z. , Arteche R. , Ceballos C. , Fang N. , Gan Y. , Murin Y. , Yi L. , Sun X.
Published: August 2022

This paper presents the design and test results of a 13 Gbps 1:16 deserializer ASIC fabricated in a 55 nm CMOS technology for Nuclotron-based Ion Collider fAcility (NICA) Multi Purpose Detector (MPD) project. The deserializer would be used in the downlink data transmission of MPD readout system to recover the serial data from the back-end to the parallel data for the front-end. The ASIC adopts a tree-type structure, consisting of a high-speed data receiver (RXDATA), a high-speed clock receiver (RXCLK), four levels of demultiplexer (DEMUX) modules, clock dividers and 16 Low-Voltage Differential Signaling (LVDS) drivers. The demultiplexer modules are composed of different numbers of high-speed DEMUX unit and low-speed DEMUX unit. The high-speed DEMUX unit and the high-frequency clock divider adopt an optimized compressed current mode logic (CML) differential structure to ensure the bandwidth with limited voltage headroom. The low-speed DEMUX unit and the low-frequency clock divider use CMOS latch to save power consumption. The duty cycle correction (DCC) circuit and the clock aligner are employed in the clock paths to ensure the correct duty cycle and aligned clock edges. In the chip test, the ASIC receives 13 Gbps serial data and outputs 16 channels of 812.5 Mbps data correctly with wide-open eye diagram. The tested power consumption is 203 mA with 1.2 V power supply including the RXDATA, the RXCLK and the 16 channels of LVDS drivers, and the core power consumption is 122.7 mA.
Grid ionization chamber based on stainless steel woven wire mesh
Authors: Li Meng , He Zhoubo , Xiao Chaoyuan , Qiu Tianli , Yang Yuansheng , Ma Peng , Lu Chengui , Wei Xianglun , Hu Rongjiang , Duan Limin , Yang Herun
Published: August 2022

The grid electrode of the grid ionization chamber (GIC) is
devoted to eliminating the dependence of the anode pulse amplitude
on the initial position and orientation of the ionization. The
traditional methods of grid production require cumbersome processes
and advanced instruments. In this paper, a bonded stainless steel
woven wire mesh (SSWWM) grid electrode manufacturing method is
proposed. Compared with the traditional grid electrode, the SSWWM
grid features the advantages of simple fabrication, low cost, and
high mechanical strength. The energy resolutions of the 40-mesh,
60-mesh and 80-mesh SSWWM grids and orthogonal mesh grid realized by
the traditional wire winding method were tested using an 241Am
source (around 5.486 MeV). The results show that the optimum energy
resolution of the SSWWM and orthogonal mesh grids is approximately
47 keV full width at half-maximum (FWHM). The optimal energy
resolutions of the 40-mesh and 60-mesh SSWWM grids are comparable,
but the initial operating voltages corresponding to the energy
resolution plateau are different, mainly because of the effect of
the different geometric parameters of the SSWWM grid on the electron
transmittance. A simulation program was used to study the electron
transmittance of the SSWWM grid. The simulation results are in
agreement with the experimental results, indicating that the
simulation program can be used as a reference for the selection of
the geometric parameters of the SSWWM grid.
4D printing: a cutting-edge platform for biomedical applications
Authors: Afzali Naniz Moqaddaseh , Askari Mohsen , Zolfagharian Ali , Afzali Naniz Mehrdad , Bodaghi Mahdi
Published: August 2022

Nature’s materials have evolved over time to be able to respond to environmental stimuli by generating complex structures that can change their functions in response to distance, time, and direction of stimuli. A number of technical efforts are currently being made to improve printing resolution, shape fidelity, and printing speed to mimic the structural design of natural materials with three-dimensional printing. Unfortunately, this technology is limited by the fact that printed objects are static and cannot be reshaped dynamically in response to stimuli. In recent years, several smart materials have been developed that can undergo dynamic morphing in response to a stimulus, thus resolving this issue. Four-dimensional (4D) printing refers to a manufacturing process involving additive manufacturing, smart materials, and specific geometries. It has become an essential technology for biomedical engineering and has the potential to create a wide range of useful biomedical products. This paper will discuss the concept of 4D bioprinting and the recent developments in smart materials, which can be actuated by different stimuli and be exploited to develop biomimetic materials and structures, with significant implications for pharmaceutics and biomedical research, as well as prospects for the future.
Underestimation of the impact of land cover change on the biophysical environment of the Arctic and boreal region of North America
Authors: Dashti Hamid , Smith William K , Huo Xueli , Fox Andrew M , Javadian Mostafa , Devine Charles J , Behrangi Ali , Moore David J P
Published: August 2022

The Arctic and Boreal Region (ABR) is subject to extensive land cover change (LCC) due to elements such as wildfire, permafrost thaw, and shrubification. The natural and anthropogenic ecosystem transitions (i.e. LCC) alter key ecosystem characteristics including land surface temperature (LST), albedo, and evapotranspiration (ET). These biophysical variables are important in controlling surface energy balance, water exchange, and carbon uptake which are important factors influencing the warming trend over the ABR. However, to what extent these variables are sensitive to various LCC in heterogeneous systems such as ABR is still an open question. In this study, we use a novel data-driven approach based on high-resolution land cover data (2003 and 2013) over four million km2 to estimate the impact of multiple types of ecosystem transitions on LST, albedo, and ET. We also disentangle the contribution of LCC vs. natural variability of the system in changes in biophysical variables. Our results indicate that from 2003 to 2013 about 46% (∼2 million km2) of the region experienced LCC, which drove measurable changes to the biophysical environment across ABR over the study period. In almost half of the cases, LCC imposes a change in biophysical variables against the natural variability of the system. For example, in ∼35% of cases, natural variability led to −1.4 ± 0.9 K annual LST reduction, while LCC resulted in a 0.9 ± 0.6 K LST increase, which dampened the decrease in LST due to natural variability. In some cases, the impact of LCC was strong enough to reverse the sign of the overall change. Our results further demonstrate the contrasting sensitivity of biophysical variables to specific LCC. For instance, conversion of sparsely vegetated land to a shrub (i.e. shrubification) significantly decreased annual LST (−2.2 ± 0.1 K); whereas sparsely vegetated land to bare ground increased annual LST (1.6 ± 0.06 K). We additionally highlight the interplay between albedo and ET in driving changes in annual and seasonal LST. Whether our findings are generalizable to the spatial and temporal domain outside of our data used here is unknown, but merits future research due to the importance of the interactions between LCC and biophysical variables.
Key regions in the modulation of seasonal GMST variability by analyzing the two hottest years: 2016 vs. 2020
Authors: Li Ke-Xin , Zheng Fei , Luo De-Yang , Sun Cheng , Zhu Jiang
Published: August 2022

Following the end of the decadal-warming-hiatus in 2016, the global mean surface temperature (GMST) abruptly showed a 3 yr warming slowdown and peaked again in 2020, overturning the conventional concept that highest GMST occurs with strong El Niño. The high GMST in 2016 was controlled by secular trend and annual variability (ANV). However, the dominator of the sharp GMST rise in 2020 was SCT alone because the ANVs in different seasons canceled each other out in 2020, contributing little to the annual mean GMST. By analyzing the two hottest years, 2016 and 2020, we identified that seasonally varying ANVs are mainly located in Eurasia, North America, the Arctic Ocean, and the tropical eastern Pacific Ocean. Dominance by surface temperatures over the four crucial regions on the subseasonal-to-seasonal (S2S) GMST variations was also observed in 73% of the years during 1982–2021, indicating a potential opportunity to improve the S2S GMST forecast.
Nature’s contributions to people and the Sustainable Development Goals in Nepal
Authors: Adhikari Biraj , Prescott Graham W , Urbach Davnah , Chettri Nakul , Fischer Markus
Published: August 2022

Nature’s contributions to people (NCPs) underpin the attainment of the Sustainable Development Goals (SDGs) but are declining globally. It is therefore critical to identify the drivers of changes in NCPs, and to understand how and where NCPs can contribute towards the achievement of the SDGs. By integrating the conceptual framework of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBESs) and the SDGs, we can obtain a better understanding of how changes in the state of NCPs support or hinder attainment of the SDGs, and how changes in NCPs are driven by development interventions. We conducted a systematic synthesis of the literature to determine the state of research on NCPs, trends in NCPs and their drivers, and the contribution of NCPs towards achieving the SDGs in Nepal, a low-income and highly biodiverse country. We found that NCPs contributed positively towards the achievement of 12 SDGs. However, NCPs were reported to be declining across Nepal, ultimately undermining Nepal’s ability to achieve SDG targets. The major direct drivers of decline were land-use change, over-exploitation, and climate change. These direct drivers were linked to conventional development interventions, including agricultural expansion and the construction of road and energy infrastructure. However, some interventions, such as community forestry and protected areas, increased the supply of NCPs. Better integration of Indigenous knowledge and local practices was also reported to be effective in improving the provision of NCPs and contributing to improving livelihoods at local scales. We identified opportunities for further research in NCPs, particularly in increasing geographical representativeness and improving our understanding of non-material NCPs. Our approach of combining the IPBES conceptual framework and the SDGs enabled us to more comprehensively identify how progress towards the SDGs are mediated by NCPs and provides actionable guidelines for how to take more integrative measures to achieve the SDGs in Nepal and countries facing similar development challenges.
Interior Design Guidelines for Reducing the Negative Impacts of Electromagnetic Fields at Residential Workspace
Authors: Algumbari G A , Nagy G
Published: August 2022

Pandemic changed human lives, instructions and rules for maintaining social distancing to limit the spread of the virus were imposed. Institutions were forced to adapt working from home mode, the new remote working lifestyle approach emphasizing the strong existence of e-environment facilities (e-learning, e-government, e-commerce) this led to a huge diffusion in the usage of devices that are considered man-made electromagnetic sources in indoor spaces that are poorly designed for long Electro-Magnetic Field (EMF) exposure example of these devices are computers, smartphones, wireless routers, home appliances, and other electronic devices. These EMF sources have several harmful effects on human health, such as stress, headaches, anxiety, and increase risk of cancer. Therefore, this research aims to develop interior design guidelines to reduce the electromagnetic fields negative impacts on the residential workspace in Egypt. First, a qualitative data collecting approach in literature review was conducted then a measurement scale for the protection levels have been defined. Followed by the analytical case studies analysed according to the deduced scale to identify key aspects pertaining to the design for space that reduces (EMF). Research findings provide a guideline for protecting occupants from excessive electrosmog exposure by using light finishing colours, following design standards, right furniture arrangement, ergonomics, relying on natural lighting, ventilation and applying shielding materials.
New Healthcare Design Guidelines for the Diagnostic Radiology Department in the Tertiary Healthcare Facilities
Authors: Eltahlawy Dalia , Zaki Mahmoud , Eldawla Marwa Kamar
Published: August 2022

The past 10 years have witnessed significant progress in diagnostic imaging through the digital transformation, the evolution of imaging technologies, and future functional requirements. Designers and architects who specialize in healthcare must provide a modern, adaptable built environment that provides the best care for the patient. As a result, the research focused on discussing that problem through three main axes: (the first axis) a presentation of the types of diagnostic radiology methods, (the second axis) studying the relationship between information technology and the programming and planning stage of the diagnostic radiology department, (the third axis) studying the design and technical considerations and their impact on the design of the spaces of the Diagnostic Radiology Department. The results of these axes were applied during the analysis of models for hospitals inside and outside Egypt to derive a general framework to raise the efficiency of hospital design, especially the diagnostic radiology department.
Improving the Efficiency of Hospital Nursing Unit Design: an analytical study
Authors: Ibrahim E , Sherif A , Serag Eldin H
Published: August 2022

The inpatient nursing unit is one of the most important departments in a hospital building. It is where patient treatment and healing occur. Improving the efficiency of the nursing unit design may improve the length of patient stay, reduce medical errors and increase patient satisfaction, thus improving the performance of the medical services provided in the hospital. This paper addresses the architectural design factors which affect performance in a typical inpatient nursing unit. A two-step approach was used in this paper. First, the factors which influence the nursing unit performance were identified from literature. Then, typical nursing unit floor plan shapes were identified. Four floor plan shapes were selected from these for analysis. Analysis focused on the factors of flexibility of operation, ease of patient monitoring, provision of patient privacy, reduction of nurse travel time, and provision of a supportive healing environment. The racetrack floor plan has shown a higher level of performance in comparison with the other floor plan shapes. It has shown superior qualities in regard to flexibility, patient monitoring, and nurse travel distances. However, for this shape to be successfully used, sound and noise control measures should be adopted to improve performance regarding patient privacy and noise disturbance. The courtyard and radial floor plan shapes provide a medium level of performance. The radial floor plan is superior in regard to patient monitoring capabilities. Although the single corridor plan has shown higher levels of sound privacy and lower levels of noise disturbance, it did not provide good flexibility, patient monitoring, and travel distances.
Design Approach for Eccentrically Loaded Reinforced Concrete Sections
Authors: Mohamed A E
Published: August 2022

The behavior of eccentrically loaded reinforced concrete sections depends on both the eccentricity and load value. The type of failure can be determined according to the eccentricity-thickness ratio and the applied load value. Interaction diagrams can be used for designing eccentrically loaded section, but the section dimensions are required to use these diagrams. According to the section dimensions and the load value, the type of failure and the required reinforcement can be determined from the interaction diagrams. Most design codes controls the design process to ensure ductile failure. But according to the design procedures of interaction diagrams, the failure type can’t be controlled simply. This paper aims at finding a design procedure for eccentrically loaded reinforced concrete sections that enable the designer to simply control the design process and the failure mode. The proposed design approach makes the design process more direct and simplified.
Parametric Studies on Dynamic Analysis of Blast-Loaded Retrofitted RC Columns
Authors: Ameen Mahmoud K. , Beshara Fouad B. A. , Hammad Youssef M. H.
Published: August 2022

The majority of public and private facilities, existing today, were not originally designed to withstand blast loads rising from terrorist attacks. Hence, such facilities require effective countermeasures to minimize losses inflicted on property and people in the event of terrorist bombing. Retrofitting of main structural elements is very effective to increase blast resistance. In this paper, comprehensive parametric studies for the dynamic response of blast-loaded RC columns are performed using the proposed nonlinear coupled model and AUTODYN software. Many material and reinforcement parameters are considered in the paper such as concrete compressive strength, steel yield stress, longitudinal steel ratio and transverse stirrups ratio. Blast-loading parameters such as using different explosive weights, changing the stand-off distance of explosion, are also studied. Finally, the retrofitting parameters for blast-loaded columns, such as using different retrofit material types like the Carbon Fiber Reinforcing Polymers (CFRP), Glass Fiber Reinforcing Polymers (GFRP) and Steel Reinforcing Polymers (SRP) with different thicknesses for each material type, are considered. Important conclusions are drawn for the sensitivity of dynamic response and failure modes of RC columns under blast loading.
Challenges for Implementing Environmental Impact Assessment method for construction projects in Egypt
Authors: Lotfy Rodina Abd El-Raouf , Ismaeel Walaa S.E.
Published: August 2022

Assessing the environmental impact of buildings is a prime concern for many countries to abide by international agreements. Various studies have shown that the construction industry has significant implications for the consumption of energy, raw material utilization, and carbon dioxide emissions. Recent Law 9/2009 in Egypt necessitates performing an Environmental Impact Assessment (EIA) for major construction projects. There is a rising number of projects doing the EIA every year. Nevertheless, this cannot be considered a common practice till the present time and many projects are still struggling to perform the EIA studies. Hence, this study investigates the common challenges for implementing EIA for major construction projects in Egypt through a comprehensive literature review and survey among local practitioners. The results showed that the dilemma lies in the segregation of the EIA process along with the project’s phases. It also indicates problems associated with the limited availability of data and insufficient practitioners’ competencies and skills to perform the required assessment for certain impact categories.
Effect of Bentonite Content on Hydraulic Conductivity of Sand-Bentonite Mixtures Used in Landfill Liners as an Alternative to Clay Liner in Egypt
Authors: Barrima Amr , Mashhour Ibrahim M , Amer Nabil H
Published: August 2022

Compacted clays are commonly utilized as landfill liners due to their impermeable properties, however, the availability of natural clay soil may be difficult or prohibitively expensive in some regions thanks to the expense of transportation, the local soil availability or regulation. As an alternative hydraulic barrier, a compacted mixture of sand with a low percentage of bentonite (6% to 14%) was used. The purpose of this research is to investigate the applicability of bentonite available in the Egyptian market for controlling the hydraulic conductivity of sand-bentonite mixtures to be used in landfill liners. The study was divided into two phases: first, laboratory tests were conducted to identify the optimum bentonite percentage and bentonite types, using local commercial bentonite products. Then, in two distinct landfill liners layers, full-scale measurements were obtained. The experimental program demonstrated that Bentonite produced and found in the Egyptian market can be utilized in landfill liners with an acceptable quality control procedure to prevent any outcome deviation.
The role of energy conservation standards in raising quality of life: Low- Cost Housing as a Case Study
Authors: Amin Ayman A. , Ezz Eldin Noha M , Mohammed Alshaimaa H.
Published: August 2022

Low-cost housing is spread all over Egypt from the north to the upper, many issues appeared on the horizon, such as high maintenance costs, high levels of energy consumption, and the emergence of many practices for residents of these units in an attempt to adapt between their needs and the design of low buildings. One of the most important challenges impacting the quality of life is energy conservation. This paper aims to raise the quality of life in low-cost housing from the perspective of energy conservation. The research aims to ensure enough sustainable energy to maintain a quality of life. This study is based on questionnaires conducted by residents of low-cost houses projects in Egypt, namely; Mokattem and New Cairo. Trying to find the most important problem and put forward ways to improve and raise the quality of life, especially from the perspective of energy conservation. Studying the Living satisfaction in low- cost houses. These questionnaires were analysed on a proposal design and how to apply it.
Numerical modelling of apex connections in cold-formed steel gable frames
Authors: Mourad S A , Naguib A M , Alanwar H H
Published: August 2022

Cold-formed steel (CFS) sections have gained acceptance as primary elements in steel frames due to their exceptionally high strength to weight ratio. The main purpose of this research is to study the behavior of the apex joint in portals frame when subjected to monotonic vertical load. Numerical models for apex connections are developed using a finite element program to study the behavior of the connection. The numerical model is first verified by comparing its results with available experimental and numerical results. After the verification, the effect of several parameters on the connection performance was investigated. The parameters included the effect of the connecting gusset thickness and length as well as the effect of the distance between bolts. Moment-rotation relationships for different CFS apex connection numerical models were analyzed. The numerical models showed that the most significant modes of failure were gusset plate or beam web buckling. Increasing the distance between the two connected sections decreased the connection moment capacity, whereas increasing the thickness of the connecting plate enhanced the moment capacity.
Improving the Performance Grade and Traffic Loading of Egyptian Asphalt Binders by Recycled Polyethylene Modification
Authors: Eraky Ahmed , Ayoub H. S. , Osman Omar , Ouf Mohamed E. , Mostafa Abdel Zaher E.A.
Published: August 2022

Recent SUPERPAVE technology allows assessment and performance grading (PG) of modified asphalts according to AASHTO T 350–14 and ASTM D7405-15 standards. These testing protocols use modified - multiple stress creep recovery (MSCR) test, to yield the high temperature PG and the traffic level of the asphalt binder. Latest AASHTO T 350–14 test protocol is used to assess two major Egyptian bitumen products, Alex and Suez (pen 60/70) before and after polymer modification. These standard products have different fractional composition since they are obtained from different local origins. Low density polyethylene modification (LDPE) of such products leads to a major enhancement in their PGs and decreases their high temperature rutting potential. A characteristic comparison between virgin a and LDPE modified bitumen samples is provided to achieve the desired PG and traffic level for high reliability projects deployed in Egyptian hot climate regions. it was found that a 2% wt recycled LDPE modification, enhances the high temperature performance grade and the traffic grade from PG 58S-XX to PG 64S-XX for the bitumen produced by Alexandria Oil Company, and from PG 58S-XX to PG 70S-XX for the bitumen produced by Suez Oil Company.
Evaluation of Open Spaces in Relocated Communities Using Affordance Theory: Al-Asmarat Community as a Case Study
Authors: Soliman S , Attia S , Khalil H
Published: August 2022

In 2016, the urban development facility (UDF), which was previously named as informal settlement development fund (ISDF), conducted several development projects as part of the goals of Egypt 2030’s vision that supports the sustainable development goals (SDGs). UDF applies several development strategies to provide residents with better quality of life (QOL), such as relocation projects as residents move from unsafe areas to a new community where they are provided with adequate housing and basic infrastructure services. However, one major issue is that open spaces of relocated projects, despite being an important component in improving livelihoods, don’t fulfill the residents’ needs. Affordance theory provides the link between human behaviour and the function of space. Therefore, this paper aims to evaluate open spaces in relocated communities relying on the affordance theory. Accordingly, Al-Asmarat district, one of the relocated projects in Cairo, is investigated as a case study to evaluate open spaces and livelihood in the area. This qualitative study employed 10 in-depth interviews to obtain primary data from samples taken from relocated residents. The study ends with needed indicators to ensure that open spaces in relocated communities can afford socioeconomic activities for the residents to achieve more inclusive urban development.
Reducing groundwater use and mitigating floods through increasing surface water utilization in the Cimahi Region of West Java Indonesia
Authors: Purnawan M Y , Hendrayana H , Setijadji L D
Published: August 2022

Population growth and economic development increase the demands for water and land in Indonesia from year to year. In addition, various spatial and temporal changes resulted from human activities in changes in of hydrology of areas around rivers that affect the water’s quality and quantity. Groundwater conditions in the Cimahi area, West Java, show a significant groundwater decline in southern Cimahi, a problem that is now studied in this research. This research is conducted by using groundwater modelling from the Experimental Station for Groundwater in the Bandung-Soreang Groundwater Basin, then we further develop the previous model by reducing groundwater utilization and replacing it with surface water to assess the impact of this substitution on the groundwater level, and reduction of surface water runoff for flood mitigation during the modelling projection period 2021 - 2030. The study starts by identifying groundwater utilization in the research area, and then we analyze the feasibility of surface water quality and quantity as a substitute for groundwater utilization. This study concludes that groundwater utilization can be replaced by surface water utilization. Our study results show that surface water runoff can be reduced up to 2.48 m3/s and positively increase groundwater level by 11.26 m.
Flood assessment after Cempaka Cyclone 2019 in Imogiri District, Bantul Regency of Yogyakarta, Indonesia
Authors: Odm Lornn , Erzagian Egy , Wilopo Wahyu
Published: August 2022

Imogiri District is one of the areas located at the foot of the southern mountains, with many rivers crossing the area. The Cempaka Cyclone in March 2019 caused a big flood in the Imogiri district and its surrounding area. Flood may affect various sectors of the socioeconomics life of a society, such as sectors of the economy, and agriculture, especially a severe effect on environmental and surface/groundwater systems in areas. The research objective is to assess flood hazards and their impact in the Imogiri District, Bantul Regency, Yogyakarta Special Region. The research was conducted by field survey and interview with an impacted community from the flood. The outcome of this study revealed that the area with high flood-prone potentials is distributed in the eastern and central part of the study area, along the river flood zone. The flood disaster caused property and agricultural losses but did not cause any casualties. The community was unprepared for the flood disaster, which had not occurred as big as in 2017.
Mineralogy and geochemistry of Kliripan manganese ore deposit, Hargorejo Village, Kokap District, Kulonprogo Regency
Authors: Islamadina B , Warmada I W
Published: August 2022

This study discusses the mineralogy and geochemistry of manganese deposits in the Kliripan area, where manganese had been mined since the Dutch occupancy until the 1970s. Although mining has been discontinued since then, the demand for manganese has increased in various industries, prompting exploration to continue to meet this demand. We performed petrographic, XRD, and XRF analysis of the ore and wall rock samples. Jasper and grainstone from the Sentolo Formation are the two lithologies where manganese mineralization occurs. Manganese-bearing minerals include pyrolusite, manganite, rhodochrosite, and lithiophorite, while the gangue minerals consist of quartz, calcite, hematite, and clay minerals. We interpret that Jasper is a product of alteration and has MnO content as high as 5.02 wt.%. Meanwhile, the economic grade manganese ore in grainstone has an MnO content up to 48.51 wt.%. The elements Ce, Zr, Co+Ni+Cu, are important discriminants to determine the type of manganese deposit. The results showed that the diagenetic process in reductive water formed the manganese ores. Oxidation of divalent manganese ion formed pyrolusite and manganite. Rhodochrosite crystallized when dilute manganese solution reacts with CO2 from limestone diagenesis. We concluded that the Kliripan manganese ore deposit has both hydrothermal and diagenetic deposits.
Geology and the effect of compaction on base material disposal for the stability of coal disposal slopes in South Kalimantan, Indonesia
Authors: Abdullah B A , Indrawan I G B
Published: August 2022

A mining activity generally removes overburden to extract minerals. Therefore, a certain area is needed to place the overburden material. One of the parameters that can affect the stability of the disposal is the base or the foundation of the disposal area which will later be stockpiled. This study is observe influence of base disposal to the stability of slope. Based on the lithological characteristics and observations of the outcrop, the writer arranges the stratigraphy of the study area in order to determine the stratigraphic arrangement and the distribution of the rock units laterally. In general, the study area is dominated by quartz sandstone, claystone, conglomerate and loose material from older rocks. The stratigraphic sequence of the study area from old to young includes Warukin Sandstone Unit (Tmw), Dahor Layang Member Conglomerate (TQdt) and Dahor Sandstone Unit (TQd). In general, the research area is included in the structural landform unit with geomorphological control that influences the tectonic process (endogenous). Based on the results of the study, there was a significant increase related to the stability of the coal disposal slope with compaction efforts carried out on the base material.
Graphene membrane hosted compact lithium metal anode enabled by capillary force-tuned lithium infiltration
Authors: Zhao Shuaiqin , Ren Zetao , Gu Sichen , Zhang Chen , Han Junwei , Lv Wei
Published: August 2022

Lithium metal anodes, the promising anodes for next-generation batteries, are troubled by the instability and safety issues induced by the dendrite growth. Three-dimensional hosts are widely used to accommodate lithium metal to solve the above problems. However, they are constantly challenged by large thickness and excess space in the host, lowering the volumetric energy density of batteries. Here, we used the reduced graphene oxide membrane (rGOM) assembled with small graphene oxide sheets as the host and obtained a compact, ultrathin (<20 μm) and free-standing lithium metal-rGO composite anode with good flexibility and high volumetric capacity. The overlap sites derived from the stacking of small size of GO act as abundant diffusion channels for the gas release during the spark reduction process, producing narrow interlamellar space in the rGOM and thus enhancing the capillary molten Li infusion to form a compact composite anode. These sites also guide the uniform deposition of Li metal on the surface and interior of the membrane, effectively suppressing the dendrite growth. This compact composite anode delivers a high volumetric capacity (1223 mAh cm−3) and stable cycling performance in the symmetrical cells and the full cells coupled with high mass loading LiFePO4 cathode under a low N/P ratio.
Numerical simulation and performance analysis of the radiofrequency inductive cathode
Authors: QIAO Kuan , CHENG Mousen , ZHANG Fan , YANG Xiong , GUO Dawei , YANG Yuntian , DING Zhenwei
Published: August 2022

The radiofrequency (RF) inductive cathode has great prospects in space missions with long mission cycles, large speed increments, and rapid response requirements as the main electron source and neutralizer in Hall thrusters and ion thrusters. This paper proposes a comprehensive multi-physics RF inductive cathode model in which the RF electromagnetic field, electrostatic field for extracting electrons, flow field, plasma transport and electrochemical reaction process are all accounted for. Each physical field mentioned above can form a closed partial differential equation. The two-dimensional finite element code COMSOL is used to solve the multi-physics model. With this model, the formation process of the anode spot is exhibited and demonstrates the non-bipolar flow theory in practice. The simulation results demonstrate that the current jump in the RF inductive cathode is caused by the anode spot. Furthermore, the influences of preset discharge parameters such as RF power, bias voltage and actuating gas flow as well as structural parameters like the coil structure, discharge chamber size and ion collector area, emission hole size, distance between the anode target and the emission hole etc on the cathode performance are investigated, and some important optimal parameters are proposed.
Metric learning for kernel ridge regression: assessment of molecular similarity
Authors: Fabregat Raimon , van Gerwen Puck , Haeberle Matthieu , Eisenbrand Friedrich , Corminboeuf Clémence
Published: August 2022

Supervised and unsupervised kernel-based algorithms widely used in the physical sciences depend upon the notion of similarity. Their reliance on pre-defined distance metrics—e.g. the Euclidean or Manhattan distance—are problematic especially when used in combination with high-dimensional feature vectors for which the similarity measure does not well-reflect the differences in the target property. Metric learning is an elegant approach to surmount this shortcoming and find a property-informed transformation of the feature space. We propose a new algorithm for metric learning specifically adapted for kernel ridge regression (KRR): metric learning for kernel ridge regression (MLKRR). It is based on the Metric Learning for Kernel Regression framework using the Nadaraya-Watson estimator, which we show to be inferior to the KRR estimator for typical physics-based machine learning tasks. The MLKRR algorithm allows for superior predictive performance on the benchmark regression task of atomisation energies of QM9 molecules, as well as generating more meaningful low-dimensional projections of the modified feature space.
The bar involution for quantum symmetric pairs – hidden in plain sight
Authors: Kolb Stefan
Published: August 2022

We show that all quantum symmetric pair coideal subalgebras

B

c

\mathcal {B}_{\mathbf {c}}

of Kac-Moody type have a bar involution for a suitable choice of parameters

c

{\mathbf {c}}

. The proof relies on a generalized notion of quasi

K
K

-matrix. The proof does not involve an explicit presentation of

B

c

\mathcal {B}_{\mathbf {c}}

in terms of generators and relations.
Predicting ncRNA–protein interactions based on dual graph convolutional network and pairwise learning
Authors: Zhuo Linlin , song bosheng , liu yuansheng , Li Zejun , Fu Xiangzheng
Published: August 2022

Noncoding RNAs (ncRNAs) have recently attracted considerable attention due to their key roles in biology. The ncRNA–proteins interaction (NPI) is often explored to reveal some biological activities that ncRNA may affect, such as biological traits, diseases, etc. Traditional experimental methods can accomplish this work but are often labor-intensive and expensive. Machine learning and deep learning methods have achieved great success by exploiting sufficient sequence or structure information. Graph Neural Network (GNN)-based methods consider the topology in ncRNA–protein graphs and perform well on tasks like NPI prediction. Based on GNN, some pairwise constraint methods have been developed to apply on homogeneous networks, but not used for NPI prediction on heterogeneous networks. In this paper, we construct a pairwise constrained NPI predictor based on dual Graph Convolutional Network (GCN) called NPI-DGCN. To our knowledge, our method is the first to train a heterogeneous graph-based model using a pairwise learning strategy. Instead of binary classification, we use a rank layer to calculate the score of an ncRNA–protein pair. Moreover, our model is the first to predict NPIs on the ncRNA–protein bipartite graph rather than the homogeneous graph. We transform the original ncRNA–protein bipartite graph into two homogenous graphs on which to explore second-order implicit relationships. At the same time, we model direct interactions between two homogenous graphs to explore explicit relationships. Experimental results on the four standard datasets indicate that our method achieves competitive performance with other state-of-the-art methods. And the model is available at https://github.com/zhuoninnin1992/NPIPredict
BERN2: an advanced neural biomedical named entity recognition and normalization tool
Authors: Sung Mujeen , Jeong Minbyul , Choi Yonghwa , Kim Donghyeon , Lee Jinhyuk , Kang Jaewoo
Published: August 2022

In biomedical natural language processing, named entity recognition (NER) and named entity normalization (NEN) are key tasks that enable the automatic extraction of biomedical entities (e.g. diseases and drugs) from the ever-growing biomedical literature. In this article, we present BERN2 (Advanced Biomedical Entity Recognition and Normalization), a tool that improves the previous neural network-based NER tool by employing a multi-task NER model and neural network-based NEN models to achieve much faster and more accurate inference. We hope that our tool can help annotate large-scale biomedical texts for various tasks such as biomedical knowledge graph construction.

Availability and implementation

Web service of BERN2 is publicly available at http://bern2.korea.ac.kr. We also provide local installation of BERN2 at https://github.com/dmis-lab/BERN2.

Supplementary information

Supplementary data are available at Bioinformatics online.
A tale of two recoveries: uncovering the imbalance between state-driven production and private consumption in post-pandemic Wuhan, China
Authors: Li Ziming , Chen Xiangming , Wang Lei
Published: August 2022

The world’s first epicentre of Covid-19 that contained the virus early and recovered quickly, Wuhan, the capital city of China’s Hubei province, offers a rare case for examining the effective but unbalanced role of the Chinese state in recovering a post-Covid city against a continued zero-Covid policy. Due to institutional inertia in policy-making, Wuhan has experienced a two-track recovery of (i) rapid GDP growth from infrastructure investment fuelled by government stimuli and large state-owned enterprises, and (ii) a weak recovery for small private businesses and grassroots consumption. Combining analyses of city-level data and survey/interview information, this paper examines the unbalanced role of the Chinese state in producing Wuhan’s uneven two-track economic recovery and its implications for recalibrating the roles of the central versus local governments and empowering the latter to rebalance from production to consumption and to improve livelihood.