bluuebunny/crossref_metadata_2025 huggingface dataset:
Temperature and current sensitivity extraction of optical superconducting transition-edge sensors based on a two-fluid model*
Authors: Geng Yue , Li Pei-Zhan , Zhong Jia-Qiang , Zhang Wen , Wang Zheng , Miao Wei , Ren Yuan , Shi Sheng-Cai
Published: July 2021

Optical superconducting transition-edge sensor (TES) has been widely used in quantum information, biological imaging, and fluorescence microscopy owing to its high quantum efficiency, low dark count, and photon number resolving capability. The temperature sensitivity (αI
) and current sensitivity (βI
) are important parameters for optical TESs, which are generally extracted from the complex impedance. Here we present a method to extract αI
and βI
based on a two-fluid model and compare the calculated current–voltage curves, pulse response, and theoretical energy resolution with the measured ones. This method shows qualitative agreement that is suitable for further optimization of optical TESs.
Effect of deformation of diamond anvil and sample in diamond anvil cell on the thermal conductivity measurement*
Authors: Jia Caihong , Jiang Dawei , Cao Min , Ji Tingting , Gao Chunxiao
Published: July 2021

Studies show that the sample thickness is an important parameter in investigating the thermal transport properties of materials under high-temperature and high-pressure (HTHP) in the diamond anvil cell (DAC) device. However, it is an enormous challenge to measure the sample thickness accurately in the DAC under severe working conditions. In conventional methods, the influence of diamond anvil deformation on the measuring accuracy is ignored. For a high-temperature anvil, the mechanical state of the diamond anvil becomes complex and is different from that under the static condition. At high temperature, the deformation of anvil and sample would be aggravated. In the present study, the finite volume method is applied to simulate the heat transfer mechanism of stable heating DAC through coupling three radiative-conductive heat transfer mechanisms in a high-pressure environment. When the temperature field of the main components is known in DAC, the thermal stress field can be analyzed numerically by the finite element method. The obtained results show that the deformation of anvil will lead to the obvious radial gradient distribution of the sample thickness. If the top and bottom surfaces of the sample are approximated to be flat, it will be fatal to the study of the heat transport properties of the material. Therefore, we study the temperature distribution and thermal conductivity of the sample in the DAC by thermal-solid coupling method under high pressure and stable heating condition.
Adsorption and rotational barrier for a single azobenzene molecule on Au(111) surface*
Authors: Hao Dong , Tang Xiangqian , Wang Wenyu , An Yang , Wang Yueyi , Shan Xinyan , Lu Xinghua
Published: July 2021

The orientation switching of a single azobenzene molecule on Au(111) surface excited by tunneling electrons and/or photons has been demonstrated in recent experiments. Here we investigate the rotation behavior of this molecular rotor by first-principles density functional theory (DFT) calculation. The anchor phenyl ring prefers adsorption on top of the fcc hollow site, simulated by a benzene molecule on close packed atomic surface. The adsorption energy for an azobenzene molecule on Au(111) surface is calculated to be about 1.76 eV. The rotational energy profile has been mapped with one of the phenyl rings pivots around the fcc hollow site, illustrating a potential barrier about 50 meV. The results are consistent with experimental observations and valuable for exploring a broad spectrum of molecules on this noble metal surface.
SU(3) spin-orbit coupled fermions in an optical lattice
Authors: Zhou Xiaofan , Chen Gang , Jia Suo-Tang
Published: July 2021

We propose a scheme to realize the SU(3) spin–orbit coupled three-component fermions in an one-dimensional optical lattice. The topological properties of the single-particle Hamiltonian are studied by calculating the Berry phase, winding number and edge state. We also investigate the effects of the interaction on the ground-state topology of the system, and characterize the interaction-induced topological phase transitions, using a state-of-the-art density-matrix renormalization-group numerical method. Finally, we show the typical features of the emerging quantum phases, and map out the many-body phase diagram between the interaction and the Zeeman field. Our results establish a way for exploring novel quantum physics induced by the SOC with SU(N) symmetry.
Superchiral fields generated by nanostructures and their applications for chiral sensing*
Authors: Zhang Huizhen , Zhang Weixuan , Hou Saisai , Wang Rongyao , Zhang Xiangdong
Published: July 2021

Chirality is ubiquitous in natural world. Although with similar physical and chemical properties, chiral enantiomerscould play different roles in biochemical processes. Discrimination of chiral enantiomers is extremely important in biochemical, analytical chemistry, and pharmaceutical industries. Conventional chiroptical spectroscopic methods are disadvantageous at a limited detection sensitivity because of the weak signals of natural chiral molecules. Recently, superchiral fields were proposed to effectively enhance the interaction between light and molecules, allowing for ultrasensitive chiral detection. Intensive theoretical and experimental works have been devoted to generation of superchiral fields based on artificial nanostructures and their application in ultrasensitive chiral sensing. In this review, we present a survey on these works. We begin with the introduction of chiral properties of electromagnetic fields. Then, the optical chirality enhancement and ultrasensitive chiral detection based on chiral and achiral nanostructures are discussed respectively. Finally, we give a short summary and a perspective for the future ultrasensitive chiral sensing.
Nanoscale structural investigation of Zn1–x
Mg
x
O alloy films on polar and nonpolar ZnO substrates with different Mg contents*
Authors: Liang Xin , Zhou Hua , Wang Hui-Qiong , Zhang Lihua , Kisslinger Kim , Kang Junyong
Published: July 2021

Zn1–x
Mg
x
O alloy films are important deep ultraviolet photoelectric materials. In this work, we used plasma-assisted molecular beam epitaxy to prepare Zn1–x
Mg
x
O films with different magnesium contents on polar (0001) and nonpolar (

10

1
¯

0

) ZnO substrates. The nanoscale structural features of the grown alloy films as well as the interfaces were investigated. It was observed that the cubic phases of the alloy films emerged when the Mg content reached 20% and 37% for the alloy films grown on the (0001) and (

10

1
¯

0

) ZnO substrates, respectively. High-resolution transmission electron microscopy images revealed cubic phases without visible hexagonal phases for the alloy films with more than 70% magnesium, and the cubic phases exhibited three-fold and two-fold rotations for the alloy films on the polar (0001) and nonpolar (

10

1
¯

0

) ZnO substrates, respectively. This work aims to provide references for monitoring the Zn1–x
Mg
x
O film structure with respect to different substrate orientations.
Effect of structural vacancies on lattice vibration, mechanical, electronic, and thermodynamic properties of Cr5BSi3
Authors: Dong Tian-Hui , Zhang Xu-Dong , Yang Lin-Mei , Wang Feng
Published: July 2021

In recent years, transition metal silicides have become the potential high temperature materials. The ternary silicide has attracted the attention of scientists and researchers. But their inherent brittle behaviors hinder their wide applications. In this work, we use the first-principles method to design four vacancy defects and discuss the effects of vacancy defects on the structural stability, mechanical properties, electronic and thermodynamic properties of hexagonal Cr5BSi3 silicide. The data of lattice vibration and thermodynamic parameters indicate that the Cr5BSi3 with different atomic vacancies can possess the structural stabilities. The different atomic vacancies change the mechanical properties and induce the Cr5BSi3 to implement the brittle-to-ductile transition. The shear deformation resistance and volume deformation resistance of Cr5BSi3 are weakened by different vacancy defects. But the brittleness behavior is remarkably improved. The structural stability and brittle-to-ductile transition of Cr5BSi3 with different vacancies are explored by the electronic structures. Moreover, the thermal parameters indicate that the Cr5BSi3 with vacancies exhibit different thermodynamic properties with temperature rising.
Determination of quantum toric error correction code threshold using convolutional neural network decoders
Authors: Wang Hao-Wen , Xue Yun-Jia , Ma Yu-Lin , Hua Nan , Ma Hong-Yang
Published: July 2021

Quantum error correction technology is an important solution to solve the noise interference generated during the operation of quantum computers. In order to find the best syndrome of the stabilizer code in quantum error correction, we need to find a fast and close to the optimal threshold decoder. In this work, we build a convolutional neural network (CNN) decoder to correct errors in the toric code based on the system research of machine learning. We analyze and optimize various conditions that affect CNN, and use the RestNet network architecture to reduce the running time. It is shortened by 30%–40%, and we finally design an optimized algorithm for CNN decoder. In this way, the threshold accuracy of the neural network decoder is made to reach 10.8%, which is closer to the optimal threshold of about 11%.The previous threshold of 8.9%–10.3% has been slightly improved, and there is no need to verify the basic noise.
Mobility edges and reentrant localization in one-dimensional dimerized non-Hermitian quasiperiodic lattice*
Authors: Jiang Xiang-Ping , Qiao Yi , Cao Jun-Peng
Published: July 2021

The mobility edges and reentrant localization transitions are studied in one-dimensional dimerized lattice with non-Hermitian either uniform or staggered quasiperiodic potentials. We find that the non-Hermitian uniform quasiperiodic disorder can induce an intermediate phase where the extended states coexist with the localized ones, which implies that the system has mobility edges. The localization transition is accompanied by the

P
T

symmetry breaking transition. While if the non-Hermitian quasiperiodic disorder is staggered, we demonstrate the existence of multiple intermediate phases and multiple reentrant localization transitions based on the finite size scaling analysis. Interestingly, some already localized states will become extended states and can also be localized again for certain non-Hermitian parameters. The reentrant localization transitions are associated with the intermediate phases hosting mobility edges. Besides, we also find that the non-Hermiticity can break the reentrant localization transition where only one intermediate phase survives. More detailed information about the mobility edges and reentrant localization transitions are presented by analyzing the eigenenergy spectrum, inverse participation ratio, and normalized participation ratio.
Boron at tera-Pascal pressures
Authors: Hu Peiju , Peng Junhao , Xie Xing , Wen Minru , Zhang Xin , Wu Fugen , Dong Huafeng
Published: July 2021

The study of boron structure is fascinating because boron has various allotropes containing boron icosahedrons under pressure. Here, we propose a new boron structure (space group

F
m

3
¯

m

) that is dynamically stable at 1.4 tera-Pascal (TPa) using density functional theory and an evolutionary algorithm. The unit cell of this structure can be viewed as a structure with a boron atom embedded in the icosahedron. This structure behaves as a metal, and cannot be stable under ambient pressure. Furthermore, we found electrons gather in lattice interstices, which is similar to that of the semiconductor Na or Ca2N-II under high pressure. The discovery of this new structure expands our comprehension of high-pressure condensed matter and contributes to the further development of high-pressure science.
Band offsets and electronic properties of the Ga2O3/FTO heterojunction via transfer of free-standing Ga2O3 onto FTO/glass*
Authors: Wang Xia , Gu Wei-Fang , Qiao Yong-Feng , Feng Zhi-Yong , An Yue-Hua , Zhang Shao-Hui , Liu Zeng
Published: July 2021

The determination of band offsets is crucial in the optimization of Ga2O3-based devices, since the band alignment types could determine the operations of devices due to the restriction of carrier transport across the heterogeneous interfaces. In this work, the band offsets of the Ga2O3/FTO heterojunction are studied using x-ray photoelectron spectroscopy (XPS) based on Kraut’s method, which suggests a staggered type-II alignment with a conduction band offset (Δ E
C) of 1.66 eV and a valence band offset (Δ E
V) of –2.41 eV. Furthermore, the electronic properties of the Ga2O3/FTO heterostructure are also measured, both in the dark and under ultraviolet (UV) illuminated conditions (254 nm UV light). Overall, this work can provide meaningful guidance for the design and construction of oxide hetero-structured devices based on wide-bandgap semiconducting Ga2O3.
Improving motor imagery classification during induced motor perturbations
Authors: Vidaurre C , Jorajuría T , Ramos-Murguialday A , Müller K-R , Gómez M , Nikulin V V
Published: July 2021

Objective. Motor imagery is the mental simulation of movements. It is a common paradigm to design brain-computer interfaces (BCIs) that elicits the modulation of brain oscillatory activity similar to real, passive and induced movements. In this study, we used peripheral stimulation to provoke movements of one limb during the performance of motor imagery tasks. Unlike other works, in which induced movements are used to support the BCI operation, our goal was to test and improve the robustness of motor imagery based BCI systems to perturbations caused by artificially generated movements. Approach. We performed a BCI session with ten participants who carried out motor imagery of three limbs. In some of the trials, one of the arms was moved by neuromuscular stimulation. We analysed 2-class motor imagery classifications with and without movement perturbations. We investigated the performance decrease produced by these disturbances and designed different computational strategies to attenuate the observed classification accuracy drop. Main results. When the movement was induced in a limb not coincident with the motor imagery classes, extracting oscillatory sources of the movement imagination tasks resulted in BCI performance being similar to the control (undisturbed) condition; when the movement was induced in a limb also involved in the motor imagery tasks, the performance drop was significantly alleviated by spatially filtering out the neural noise caused by the stimulation. We also show that the loss of BCI accuracy was accompanied by weaker power of the sensorimotor rhythm. Importantly, this residual power could be used to predict whether a BCI user will perform with sufficient accuracy under the movement disturbances. Significance. We provide methods to ameliorate and even eliminate motor related afferent disturbances during the performance of motor imagery tasks. This can help improving the reliability of current motor imagery based BCI systems.
Tuning Parameters of ANFIS Model Using Chaotic Particle Swarm Optimization Algorithm
Authors: Najim Fatima Hashim , Qasim Omar Saber
Published: July 2021

In recent years, researchers have worked to find multiple methods to overcome the classification problems they encountered. In this paper, both the Chaotic Particle Swarm Optimization (CPSO) algorithm are connected with the Adaptive Fuzzy Inference System (AFIS) model, through two stages, the first stage, CPSO algorithm is used to tune parameters of the fuzzy inference system model. In the second stage, the fuzzy inference system model is constructed according to the optimum parameters that are found by the CPSO algorithm. The proposed CPSO-AFIS algorithm demonstrated efficacy and efficiency compared to the standard algorithm Adaptive Neuro Fuzzy Inference System (ANFIS).
Flood Behavior of Al-Hammar Marshes
Authors: Yaseen Sarah T. , Shaban Auday H. , Jasim Kareem A.
Published: July 2021

The marshes of southern Iraq are among the most important and largest wetlands in the Middle East and the world are characterized by the freshness of their waters and their environmental diversity. The marshes have undergone many changes during the past decades and to discover and study these changes, remote sensing data will be used as sources of information and data in this study represented by the Landsat 8 satellite images (OLI), the images were collected for years from 2013 to 2019, and by applying remote sensing techniques and geographic information systems techniques, changes in Al-Hammar marsh were detected during the past seven years, the supervised classification method (maximum likelihood) was applied to classify the region Were identified six main categories of the land cover (deep water, shallow water, small cane, large cane, plant, soil) using the software (ENVI 5.3), the final maps were produced for classification using (ArcGIS 10.4.1) software, the results showed Significant change in the water content of Al-Hammar marsh and the increase in the proportion of flooding during the year 2019 to the highest rate since 2013. In addition, the results showed the accuracy and success of the supervised classification method (maximum likelihood) in the classification of images as they are considered the best classification methods, the fastest and high accuracy.
The influence of temperature and size on the absorption coefficient of CdSe quantum dots
Authors: Hammadand Roaa Sh. , Abdul-Ameer Nidhal M.
Published: July 2021

Because of Cadmium selenide quantum dots (CdSe quantum dots) has a tuning energy gap in the visible light range, therefore; it is provided a simple theoretical model for the absorption coefficient of CdSe quantum dots, where the absorption coefficient determines the extent to which the light of a material can penetrate a specific wavelength before it is absorbed. CdSe quantum dots have an energy gap can be controlled through two effects: the temperature and the dot size of them. It is found that; there is an absorption threshold for each directed wavelength, where CdSe quantum dots begin to absorb the visible spectrum at a size of 1.4 nm at room temperature for a directed wavelength 300 nm. It has been observed that; when the wavelength is increasing its absorption threshold is increased. For wavelengths (400, 500, 600) nm, the absorption thresholds for each quantum sizes are (1.8, 2.2. 3.2)nm respectively. On the other hand, a rising of the temperature led to reduces the absorption coefficient value, that at 400 K for all quantum sizes, the absorption coefficient increases >2000cm−1(According to the directed wavelength) than it is at 0 K. CdSe quantum dots can be considered as one of the most promising materials because it has a tuning gap for the visible wavelengthsfor different applications, such as light-emitting diodes in different colors of the visible spectrum. It is found that; there is a good agreement between our theoretical calculations and experimental results.
Investigation of Single-Phase Flow Characteristics in an Inline Pin-Fins Complex Geometry
Authors: Shakir R.
Published: July 2021

In this guess investigation of concerns R113 heat transfer of pressure drop flow in single-phase flow in inline on the square shape of micro-channel of pin-fins own a (5×5 mm2) cross-area segment section via of (5 mm) heightly. Therefore, the inline square micro-channel of pin-fins complex geometry additionally owning (25) numbers of the pin-fins, total pin-fins channel dimension (50 mm × 50 mm). Subsequently. The liquid has (25°C) inlet temperature for the same inlet temperature six mass flow rates were applied, ranging from (0.0025 - 0.01 kg/sec), and heat apply ranged from (40-200 Watts). Guess single-phase heat transfer coefficients, guess liquid temperatures and guess wall temperatures were reported in this investigation.
Investigation of Potential Marine Bacterial Isolates in Biodegradation Methods on Hydrocarbon Contamination
Authors: Armus R , Selry C , Marzuki I , Hasan H , Syamsia  , Sapar A
Published: July 2021

Hydrocarbon pollution, especially polycyclic aromatic hydrocarbons which are toxic, carcinogenic and mutagenic in the sea, has a negative impact on biota and must be controlled. Identification and isolation of bacteria that have the potential to degrade hydrocarbons in the sea need to be done to overcome the hydrocarbon pollution. The methods used include quantitative test for biodegradation capacity, identification of bacterial species, phenotype test for gram staining, biochemical test, and genotype test using PCR. The results of identification, selection and optimization of isolates, obtained seven types of consortium bacterial isolates with codes BI, BA, AB, BS, BP, BASA and BAPS which have the potential to degrade hydrocarbon contaminants. The phenotypic data showed that there were 3 isolates from the group of gram-positive Baccilus bacteria, while based on the genotype data, the three isolates were identified as Bacillus infantis and Acinetobacter baumannii. The results of the biodegradation activity test showed that the bacterial isolate was able to reduce the surface tension of aliphatic and aromatic hydrocarbons, so that the bacteria could act as a degrading hydrocarbon pollutant.
Adaptation of Climate Change to Vulnerability of Raw Water Availability in Bantaeng, South Sulawesi
Authors: Rusli M , Chaerul M , Marzuki I
Published: July 2021

Various processes triggering global climate change and climate change have been accepted by many parties as a necessity characterized by global warming, with a direct impact on the hydrological cycle, so that climate change is believed to have a real impact on water resources. Taking into account the possible consequences of climate change, it will be extremely important to examine how fluctuation in temperature and rainfall pattern shift will affect the water supply system. With this climate change, it will lead to vulnerability to the availability of raw water. The vulnerability referred to in Bantaeng was simply determined by three factors that were considered dominant, namely water needs, water sources, and community welfare. The analysis results showed that there was a higher risk increase which was influenced by hydrogeological conditions related to groundwater potential. Optimal groundwater management was expected to contribute as an adaptation effort to climate change risks to water sources.
Describing Representation Ability of Prospective Science Teacher Based on Learning Style
Authors: Yunus S R , Tawil M , Muhiddin N H , Muhiddin S M A , Alim M H
Published: July 2021

The ability to represent a phenomenon in various forms either graphically, mathematically, in diagrams, etc. is the ability of multiple representations. This study aims to provide an overview of the multiple representation abilities of prospective science teacher based on their learning styles. The sample was 59 students of the 4th semester of Science Education Study Program, Universitas Negeri Makassar who took course of Fluid. The research instrument used were a learning style test and a representation ability test on dynamic fluid material in the form of multiple choices. The results of the learning style test showed that 21 are auditory learner, 11 are kinesthetic, and 27 are visual. Furthermore, the results of the representation ability test related to image representation, graphic representation, verbal representation and symbolic representation were analysed according to the visual, auditory, and kinesthetic learning styles. The results of data analysis showed that the highest average value of graphic representation ability was owned by students with a visual learning style in the medium category. Furthermore, the highest value of the ability to represent images, symbols, and verbal was had by kinesthetic learner with each category, medium, high, and high. Based on these results it can be concluded that science teacher candidates with kinesthetic learning styles have better representation abilities than the other two learning styles.
The contribution of land cover change to the decline of honey yields in the Northern Great Plains
Authors: Smith David , Davis Amélie , Hitaj Claudia , Hellerstein Daniel , Preslicka Amanda , Kogge Emma , Mushet David , Lonsdorf Eric
Published: July 2021

Decreased availability of forage, as well as increased pesticide exposure, are important factors in the decline of honey bee health. Here, we isolate land cover transitions and their effect on honey production at 160 commercial apiaries in the Northern Great Plains. We found that land cover changes from 2008 to 2012 caused an annual decline in honey yields of 0.9% in the study area. Transitions from grassland to soybean (but not corn) were particularly detrimental to honey yields, potentially due to bee contact with pesticides within and around agricultural fields. When our results are applied to known apiary locations across all of North Dakota (U.S.A.), we estimate a 2.5% (1.6 million USD) decline in 2012 honey yields due to land cover changes occurring between 2008 and 2012. Even when controlling for changes in land cover, we found that on average colonies in the study area experienced a 14% annual decline in honey yields. We discuss possible explanations for these non-land-cover-related honey yield declines, including changing economic conditions (e.g. pollination services), changes in land management (e.g. pesticides), and increases in pests or diseases.
The association between postpartum depression and air pollution during pregnancy and postpartum period: a national population study in Taiwan
Authors: Shih Ping , Wu Chih-Da , Chiang Tung-liang , Chen Pau-Chung , Su Ta-Chen , Cheng Tsun-Jen , Chen Yi-Hua , Guo Yue Leon
Published: July 2021

Epidemiological evidence shows the association between air pollutants and several mental health outcomes, including depression, sleep disturbance, dementia, childhood neurodevelopment and suicide. Pregnant women are believed to be more susceptible and vulnerable to environmental pollutants, and postpartum depression (PPD) is a prevalent debilitating mental disorder. However, data on the effects of exposure to air pollution during pregnancy and postpartum period on the risk of PPD remain limited. This study aimed to evaluate the association between exposure to ambient air pollution during pregnancy and postpartum period and the incidence of PPD. The Taiwan Birth Cohort Study recruited representative 12% of all newborn in 2005 and their mothers by two-stage stratified sampling, including 21 248 mother–infant pairs. The occurrence of PPD was assessed by a self-reported questionnaire. Exposure to air pollutants during pregnancy and postpartum period was estimated using hybrid kriging/land-use regression (LUR) and integrated LUR-machine learning model based on data from the air monitoring stations. Logistic regression was then conducted to determine adjusted odds ratios (aORs) of PPD in relation to air pollutants. A total of 21 188 women were included in the final analysis, among whom 3,648 (17.2%) developed PPD within 6 months postpartum. The occurrence of PPD was significantly related to exposure to ambient concentrations of nitrogen dioxide (NO2) during first trimester after adjustment [aOR: 1.081 per interquartile range (10.67 ppb), 95% confidence interval: 1.003, 1.165], but not to particulate matter ⩽2.5 µm in diameter or carbon monoxide. Exposure to ambient NO2 during early pregnancy was significantly related to the occurrence of PPD among the women investigated in this population-based study.
Environmental injustice in Clean Water Act enforcement: racial and income disparities in inspection time
Authors: Konisky David M , Reenock Christopher , Conley Shannon
Published: July 2021

Decades of research has documented that people of color and low-income experience disproportionate environmental burdens, with recent empirical studies showing these burdens are exacerbated by disparities in government regulatory enforcement. Scholars’ attention to enforcement disparities as a source of environmental injustice highlights that government behavior may contribute to ongoing inequities in environmental outcomes. To date, studies analyzing enforcement disparities have employed statistical models to either estimate the probability that a federal or state agency performs an enforcement action or the total number of such actions over some duration of time. In this study, we adopt an alternative approach that analyzes the duration of time it takes for government officials to inspect a facility to determine if there is a difference based on the demographics of the host community. Specifically, we study administrative data from state implementation of the U.S. Clean Water Act (CWA), which we couple with demographic information around large, regulated facilities to analyze the relationship between response time and community characteristics. Estimating event history models, we find that state regulators’ inspection response time is slower toward noncompliant facilities located in communities that have higher percentages of poor and Hispanic citizens. With respect to Black communities, state regulators’ response time to noncompliant facilities is no different than compliant facilities. Collectively, these results indicate that state regulators are not prioritizing CWA facilities that violate performance requirements when they are in environmental justice communities.
Assisted History-Matching Based on Multiobjective Surrogate Reservoir Model for Tight Oil Reservoirs
Authors: Dong Zhenzhen , Tian Weidong , Yang Yongzhi , Jiao Tingkui , Lv Wenfeng , Zhou Yongyi , Yang Jinghui , Li Weirong
Published: July 2021

History matching and quantifying uncertainty in hydrocarbon production forecasts are considered important steps in reservoir simulations and are key processes for providing crucial information for decision making in the development of oil and gas fields. However, history matching of unconventional reservoirs with complicated fracture system is very computationally expensive and time consuming, and most of the data used are subject to high uncertainty. In addition, the objectives of history matching are usually conflicting, such as improving match of oil rate will deteriorate match of water rate. Previous studies on assisted history matching have mainly focused on optimizing a single-objective function, where the production and pressure data are combined as a single misfit value. In this study, the proposed algorithm extends the application of the proxy model to deal with multiobjective optimization in the context of reservoir history matching. Then, the resulted proxy model were conducted to analyze history-matching quality and obtain uncertainty prediction. Result suggests that the multiobjective surrogate reservoir model scheme not only could obtain reliable history matches and provide accurate uncertainty estimation, but the complexity of gridded fractures is mitigated through the workflow. The benefit of using the multiobjective surrogate reservoir model is to obtain a various set of history matched models while reducing the number of expensive reservoir simulation runs. The proposed methodology might also be useful for reservoirs in which simulation models could not reflect the production history and for those with high uncertainties in reservoir characterization.
Social impacts of oil spills towards the people living in coastal areas
Authors: Alvernia P , Soesilo T E B , Herdiansyah H
Published: July 2021

Soil and water contamination due to oil spills have caused a decline in soil and water quality and has undermined the welfare and health of people. The oil spills have affected the environment and ecosystem-based services, increasing the level of poverty and physical, mental, and occupational mobility of the people. One of the effects experienced by the people is the loss of livelihood, thus requiring them to change occupations, and some even become unemployed. The lack of support for livelihood and unemployment is identified as a long-term effect on the community. This research aims to analyze the social impacts caused by the oil spills on the research site. Moreover, the method used in this research is quantitative and qualitative. This research aims to prove that there is a change of livelihood resulting from the oil spills. What fishermen do as their occupation when not sailing is, among others, becoming freelancers, merchants, and even becoming unemployed. Those were done to generate additional income as the fishermen could not sail. However, the income received from such occupations is insufficient or lower than fishing in the sea.
Studies of fishermen’s economic loss due to oil spills
Authors: Alvernia P , Utomo S , Soesilo T E B , Herdiansyah H
Published: July 2021

Offshore oil-drilling activities have a significant potential to generate pollutants which of them is from oil spills. Oil spills in the coastal ecosystem harm the marine ecosystem and human activities. The disrupted environment of the waters by the oil spills causes social-economic losses, specifically impacting the decline of fishery products and the community’s living standard on the coast. The immediate economic effect of the oil spills is, among others, the death of marine organisms due to the oil layers on the water surface, causing economic losses to the fishermen. The decline in the marine environment quality is directly proportional to the decrease in fishermen’s incomes. The purpose of this research is to evaluate the fishermen’s economic losses caused by the oil spills. The research method used is the mixed method which is a combination of quantitative and qualitative methods. The outcome of this research is not only the damage of oil spills to the environment, but it also causes an economic impact on the people around the affected area. The connection between the environmental damage and the community’s income is due to the offshore community’s reliance on natural resources as their source of income. The average of the difference fishermen’s losses after oil spills has reached 76% or Rp. 177,875/trip, which is due to the decrease in the fish caught so that the fishermen could not sell them.
A study on desiccation cracking behavior of landfill liner developed from construction waste
Authors: Budihardjo M A , Hadiwidodo M , Wardhana I W , Tuasykal M R N A , Samadikun B P , Ramadan B S
Published: July 2021

This study was conducted on composite materials consist of construction waste, bentonite, and lime for landfill liner. In this case, Matlab version 2019a was used to analyze composite variables for desiccation crack. In the mixture of construction waste, bentonite, and lime, there is a desiccating behavior. This study found that the addition ≤ of 20% bentonite could cause more significant cracks. The addition of 1% lime can reduce the level of soil shrinkage so that cracks are less than with the addition of bentonite. The results have four variations of composites that meet the soil shrinkage limit ≤ of 4 % not to cause significant cracks.
The efficiency of biological oxygen demand removal in domestic wastewater treatment using multi soil layering
Authors: Khotimah C K , Handayani D S , Sudarno  , Syafrudin  , Hadiwidodo M , Wardhana I W
Published: July 2021

Domestic wastewater from the kitchen, bathing, and washing activities contains organic pollutants. The parameter tested was Biological Oxygen Demand (BOD). In this study, Multi Soil Layering (MSL) methods have been used as a processing method. This treatment serves to reduce ammonia levels in wastewater. This study aims to determine the removal of BOD in gray water using the Multi Soil Layering System. Wastewater samples were taken in a residential area of Semarang. In this study, there are 2 stages, namely the preparation and implementation stages. In the seeding and acclimatization process, batch reactors are used for 14-24 days. The next stage is the process of running for 20 days with intermittent flow. Soil Mixture Box (SMB) is a mixture of andosol soil and activated charcoal (reactor A), andosol soil and apus bamboo (reactor B), and andosol soil, activated charcoal and apus bamboo (reactor C). The results of domestic wastewater treatment using the MSL method respectively in the three reactors can remove BOD by 26%, 25%, and 29%.
The best practice of ecoliteracy based on social culture
Authors: Juhriati I , Rachman I , Yayoi K
Published: July 2021

This study aims to obtain an in-depth description of the best practice of eco-literacy based on social culture. The data collection techniques were carried out through observation, interview, field note, and documentation. The subjects of this study were the principal, teachers, and students of kindergarten. The collected data were analyzed using qualitative data analysis with case study techniques. The results show that ecoliteracy learning is integrated with culture and religion. It was adapted to the motto of Firdaus Percikan Iman (FPI) Kindergarten, namely the Qur’an generation, intelligent, loving the environment and culture. Ecoliteracy is learning through an artificial environment by teaching culture to children. The artificial environment has a building concept by presenting buildings that use natural materials. Each of these buildings is full of cultural values and maintains natural ecosystems. To introduce culture to the students, various activities such as introducing traditional foods, playing Mang Depot, dancing traditional dances, playing traditional games, and singing regional songs were delivered.
Utilization of tailing waste as aggregate for road pavement
Authors: Susanto I , Fransisco S , Firdaus Y , Ronny Y
Published: July 2021

Tailing waste from gold mining in Papua, Indonesia, is a severe problem for the environment. Tailing as Hazardous and Toxic Substances, the deposits so massive. On the other hand, the availability of natural aggregates for road pavement continues to run low. The problems can be solved by utilizing tailing as a road base layer with massively, fulfill specification, and save. The purpose of this research is how to utilize tailing as a road base layer. The research methods used are experiment laboratory method by physical, chemical, TCLP, and mechanical strength test. The physical analysis shows that the size of the tailing is loose and non-cohesive, so it requires binding material to increase bearing capacity. The TCLP test showed that the level of toxic material in tailing was fulfilled the threshold. The stabilization analysis of tailing with 20% clay soil produces CBR 17,3% and can only be utilized as embankment. Stabilization with 13,35% cement fulfills the target UCS 24 kg/cm2 to be used as a road base layer. Marshall test result by 60% tailing and 7% asphalt meet specifications to be asphalt road base layer.
Baseline waste management data in North Lombok District
Authors: Simorangkir A , Citrasari N , Hariyanto S , Widyastuti A
Published: July 2021

An integrated waste management system requires baseline data, including waste generation analysis, composition density, and waste characteristics. Baseline data is needed to determine the proper waste management strategy. This research was conducted by measuring directly from the source of waste carried out by stratified sampling following SNI 19-3964-1994. The location of the study was carried out in Tanjung and Gangga districts because this location is considered to represent North Lombok Regency. The research was conducted using 100 samples of household waste. The study results on the composition of waste in the North Lombok Regency consisted of organic waste, plastic waste, paper, cloth, wood, glass, metal, and rubber waste. The dominant composition is organic waste. The characteristics of waste in the North Lombok Regency have a higher water content than the water content of waste in general. All the characteristics tested indicate that the waste in North Lombok Regency requires several treatments before processing waste, such as reducing the water content and increasing the C/N ratio. Based on the characteristics and composition of the waste, composting or incineration is the suitable waste management method in North Lombok Regency.
The potential of coffee waste composting technology using microbial activators to reduce solid waste in the coffee industry
Authors: Amalia N , Widialip N F , Safira N , Citrasari N , Hariyanto S
Published: July 2021

The coffee industry in Sidoarjo produces coffee waste as coffee ground, coffee husk, and coffee return with the solid waste generation of about 5044.3 Tons/year. The coffee waste characters resemble organic waste, so it has potential as a composted raw material. This study aims to determine the selected variation raw material composition from the coffee industry based on Indonesian National Standard (SNI) Number 10-7030-2004 and the recycle potency of the coffee industry solid waste using composting technology. The research variables are the modified composting method (open windrow composting and Bacary Italian) and the co-composting method. The result of this research for all treatments showed that the concentration range of pH value 6.92-9.54, moisture 34.78-66.60%, C-organic 17.75-33.82%, N 1.45-2.93%, C/N ratio 10-13, P2O5 0.13-0.31%, and K2O 0.89-2.89%. The selected variation raw material composition of bio compost based on the compliance to SNI 10-7030-2004, which is 1.5 kg coffee ground + 1.35 coffee return + 0.15 kg coffee husk + 3 mL EM4 (K10). Based on K10 as the selected variation raw material composition of bio compost, the coffee industry solid waste recyclable is coffee ground 0.64%, coffee husk 0.20% and returned coffee 100%.
‘School visit’ improving sustainable environmental knowledge of youth living near forest borders
Authors: Septiarini R , Herdiansyah H , Siregar P G. , Gawi J
Published: July 2021

Environmental education needs to be applied to adolescent children to one day coexist and avoid conflict with wildlife in the forest. Still, the initiative makes environmentally-themed education strategies attractive to teens. To better understand the adolescent environment's educational landscape, this study focused on students in their teens. There was 2016-2017 conducting a School Visit' in 10 schools attended by 596 students in Aceh. The majority of the material emphasizes the effectiveness of game-based, rich with a fun approach that combines movement and interaction. The purpose of this study was to understand the extent of the effectiveness of the 'School Visit' program to increase knowledge related to forests and wildlife and provide input or other views on the program. This study used a review method with secondary data. The report results were positive. The knowledge of teenage students about forests and orangutans increased by 10 percent. The goal of the 'school visit' program gave the students a fresher feel so that they would be more interested in learning about forests and wildlife.
Assessment of cadmium concentration, bioavailability, and toxicity in sediments from Saguling reservoir, West Java Province
Authors: Wardhani E , Roosmini D , Notodarmojo S
Published: July 2021

This study aims to assess the concentration, bioavailability, and toxicity of cadmium in sediments. Surface sediment samples were taken from 12 sampling locations during the rainy and dry seasons from 2015-2017. Cadmium concentrations were analyzed using ICP-OES. Potential ecological risk index (PERI) methods assess the quality of lake sediments concerning heavy metal contamination. Risk Assessment Code (RAC) is a method used to assess the bioavailability of metals in aquatic sediments. The concentration of cadmium in the sediments during the rainy and dry seasons is high compared to the standards. The average concentration in rainy season 14.82 ± 1.48 mg.kg-1 and dry season 11.12 ± 2.16 mg.kg-1. Based on the assessment of sediment quality is categorized as extremely polluted during the rainy and dry seasons. The sediment quality has been contaminated with cadmium with the serious ecological risk category in two seasons. This means that Cadmium pollution has had a serious impact on the reservoir ecosystem. The bioavailability of cadmium in the dry season is higher than in the rainy season. This suggests that in the dry season, cadmium is more bioavailable and more able to enter the food chain. The toxicity of cadmium is higher in the dry season.
The mitigation strategy for reducing greenhouse gas emissions from household activities in Medan city
Authors: Suryati I , Herlina N , Hasibuan N H , Siregar R L , Husna A , Silalahi A , Audina M , Sari S
Published: July 2021

The activities of several sectors cause an increase in the amount of greenhouse gas emissions. Household activities also produce greenhouse gas emissions, mainly from cooking, electricity use, solid waste, and wastewater. The dominant greenhouse gas emissions from household activities are CO2, CH4, and N2O. This study aims to inventory greenhouse gas emissions from household activities in Medan City and determine several mitigation scenarios in reducing greenhouse gas emissions from household activities. The method used in calculating greenhouse gas emissions is the IPCC method. The results of an inventory of GHG emissions from household activities in Medan City for energy consumption (LPG and electricity) are 1.16 million tons CO2e/year, household solid waste is 36801.5 tons CO2e/year, and household wastewater is 198723.12 tons CO2e/year. The scenario of replacing LPG with an induction stove can reduce GHG emissions by an average of 21.08%, the design of using solar panels on the roof can reduce GHG emissions by an average of 30.19%, the composting scenario can reduce GHG emissions by an average of 0.38% and utilization CH4 from household wastewater as electrical energy can reduce GHG emissions by 1.23%.
Orf 1 as a gene marker for fast screening in medical waste treatment applications during a covid-19 pandemic
Authors: Rozana K
Published: July 2021

Although the Covid-19 pandemic has been going on for more than a year since it was first discovered in Wuhan, China, in mid-December 2020 until now, the pandemic is still ongoing, and there are no signs of a decrease in cases. The latest developments show that Covid-19 has undergone significant mutations in several areas in America, Europe, and Africa. The mutation of Covid-19 may be caused by environmental conditions that are not the concern of various parties. This research was conducted to find a gene marker from Covid-19 that could be used as a media for rapid screening when sorting medical mask waste so that later waste processing techniques could be carried out separately between masks that could potentially contain Covid-19 and waste that did not contain Covid-19. This research method was carried out using bioinformatics analysis, especially the genomic characterization of Covid-19 samples from 17 different countries. Based on the study results, it is known that from 17 samples of Covid-19, the ORF 1 gene was the most stable and conserved gene in all samples.