Two-dimensional monolayers such as scandium oxyhalides are future compounds for prospective optoelectronics, quantum information, and quantum technologies. These two-dimensional materials have ...attracted much attention for fundamental and applied research due to their outstanding electronic and optical properties. In this framework, we investigate the electronic and optical properties of two-dimensional ScOX (F, Cl, Br) compounds scandium-based materials employing density functional theory calculations. Our two-dimensional single-layer structures are dynamically stable, as evidenced by the phonon dispersion curves, which showed no unstable phonon modes. The TDOSs and BS calculations show that these 2D sheets are wide-band-gap semiconductors. Our spin-up and spin-down computations demonstrate that our monolayers are non-magnetic compounds. The imaginary part of the dielectric function of these two-dimensional materials disappears at around 30.00 eV, which is the energy dissipation function. Our compounds appear transparent once the incident light’s frequency surpasses the plasma frequency (30.00 eV). The importance of absorption coefficient and gap energy suggests that these materials will be an effective compounds for optoelectronic applications.
•Electronic and optical properties of ScOX (F, Cl, Br) two-dimensional scandium based-material are investigated.•Our 2D single-layer structures are dynamically stable.•The TDOSs and BS calculations show that these 2D sheets are wide-band-gap semiconductors.•Our spin-up and spin-down computations demonstrate that our monolayers are non-magnetic compounds.•Our compounds appear transparent once the incident light’s frequency surpasses the plasma frequency (30.00 eV).
Geochemical compositions, including highly siderophile element (HSE) abundances and Re-Os isotope compositions, of nine polymict impact breccias in two drill cores and three target rocks from the ...Jeokjung-Chogye structure, South Korea, have been investigated to test the impact origin of the structure, and to infer the potential projectile type for the formation of the crater. The impactites have around 5 times higher abundances of platinum-group elements (PGE) compared to target rocks, and two orders of magnitude higher Re abundances. The weighted mean for 187Os/188Os ratios of impactites is 0.806, which is lower than this value for the target rocks (1.049), suggesting the presence of a meteoritic component. The higher PGE abundances and a broad negative correlation between Os contents and 187Os/188Os ratios show that the impactites incorporated ∼0.05 wt% of a chondritic component. The endogenic or chondritic relative abundances of the HSE argue against iron meteorites as a potential impactor for the Jeokjung-Chogye structure. Yet, the present data do not allow to unambiguously identify the projectile type (i.e., chondrite class) present in the impactites because of the high proportion of the indigenous component.
•We report HSE and ReOs isotope data for impactites from the JC structure in Korea.•The impactites have 5 times higher abundances of PGE compared to the target rocks.•The impactites have 187Os/188Os ratios relatively lower than the target rocks.•Endogenic or chondritic relative HSE abundances argue against irons as impactor.•Chondritic contribution to the impact breccias is estimated to be ∼0.05% or less.
Background: Field and Objective: In today’s world, there are different building performance assessment standards, which mostly adopt an environmental approach to buildings. Standards are the common ...language of countries and the world. By providing a common language, a standard can guarantee health and safety for the entire consumers, products, and services. The global village determines a wide range of rights and responsibilities for citizens, including the areas of safety, health, environment, and saving energy. In the building industry, different performance assessment methods are practiced in the world to promote the culture of a healthy life, including the ranking systems BEAM, LEED, and BREEAM. Assessment of building performance is a complex issue because it has to meet several criteria and it is necessary to establish consistency and consistency between these criteria. These include energy consumption, acoustic performance, thermal comfort, indoor air quality and many other issues. Building performance is a critical aspect of organizational activity that is influenced by building maintenance policies and practices. Today, the measurement of building HSE performance assessment criteria is becoming an essential exercise due to legal processes and rules and individuals’ increased knowledge of the safety, health, environment, energy consumption, welfare, and elegance of buildings. Building performance assessment criteria may be employed to assess the effects of different management activities in this area, consequently providing a good mechanism to supervise the building’s performance to move toward HSE. One of the most important issues in the performance appraisal process is the impact of evaluatorschr('39') personal judgment on performance appraisal results. Research by some researchers has addressed the impact of appraisal judgments on the appraisal process and has identified this as one of the most important challenges of performance appraisal processes. The use of multi-criteria decision making models can be very effective in this regard. One of the best practices that can be addressed in this regard is DEMATEL, in which it considers the intrinsic relationships between factors affecting performance indicators. Structural models can be used to determine relationships between evaluation criteria. Interpretive structural modeling approach has been used to increase data analytics capability and reduce system complexity. ISM is an interactive learning process introduced by Warfield in 1973. Interpretive structural models are able to determine the relationship between indices that are interdependent individually or in groups, and to analyze the relationship between indices by analyzing criteria at several different levels. This study aims to identify and rank factors impacting buildings’ HSE performance via the Fuzzy DEMATEL Approach and Interpretive Structural Modeling (ISL). Methodology: This study is applicable in terms of objectives and descriptive-casual in terms of methodology. Using available resources and eight experts’ views, 24 factors were identified in four areas: 1) structure, 2) architecture, 3) mechanical, and 4) electrical. Then, they were scored by the experts on the 9-point Likert scale. Those with a mean score above 5 were selected. The experts’ selection criteria were classified into four groups. Then, their relationships and ranks were determined by using DEMATEL and ISM methods. Moreover, the relationships’ strengths and the criteria’s effectiveness and susceptibility were explored via the Fuzzy DEMATEL technique. The ISM and FDEMATEL results were used for two purposes: first, to confirm and verify the results of both methods and second, to improve the obtained results. In this study, the prioritization derived from the FDEMATEL method confirmed and improved the ISM prioritization. By combining the two methods, a conceptual model of building HSE performance assessment can be defined. The reason for using both interpretive structural modeling and DEMATEL is that the interpretive structural modeling method only determines the level of impact of the overlapping factors. And it helps to identify the internal relationships between the factors. In other words, interpretive structural modeling is a good technique for analyzing the influence of one factor on other factors and can help to prioritize and determine the level of factors in a system. Whereas, the DEMATEL method has the ability to quantify the intensity of the interactions among the factors and to show how effective the factors are with each other. Penetration-Dependency Analysis (MICMAC) Impact-dependency power analysis is used to analyze the driving forces and the dependent forces of the variables. The sum of the values in the final access matrix for each element indicates the extent of penetration and the column sum will indicate the degree of dependence. Due to their dependence on conductor factors, they are considered followers. Based on the power of influence and dependency, four groups of identifiable elements will be: 1- Autonomous Attributes: Factors that have weak influence and dependence. 2- Dependent Attributes: Factors that have low penetration power but are highly dependent. 3- Linkage Attributes: Factors that have high influence and dependence. 4- Driver Attributes: Factors that have strong influence but weak dependence. Findings: The FDEMATEL findings suggested that the structure’s safety, electrical safety, and saving energy in the mechanical area were the most effective factors, respectively, while architectural environment protection, saving architectural energy, and architectural elegance were the least important impacting factors. At the same time, ISM findings indicated that mechanical elegance and electrical welfare in the dependent group were factors with low influence but high dependence, while mechanical environment protection, saving electrical energy, and mechanical health in the independent group were factors with a strong influence but weak dependence. Based on the power of influence and dependency, four groups of identifiable elements will be: 1-Structural health factors, environmental protection of structures, energy conservation of structures, architectural health, electrical health, electrical environment and electrical beauty in the autonomous group: factors that have weak influence and dependence. 2- Mechanical aesthetic factors and electrical welfare in the dependent group: factors that have low penetration power but are highly dependent. 3- Structural safety factors, structural well-being, structural beauty, architectural safety, architectural environmental protection, architectural energy saving, architectural well-being, architectural beauty, mechanical safety, mechanical energy saving, mechanical well-being and electrical safety in Interconnected Group: Factors that have high influence and dependence. 4- Environmental protection, electrical energy saving, and mechanical health factors in the independent group: Factors that have strong penetration power but poor dependency. Conclusion: There are different performance assessment standards in the building industries of countries in the world to improve health, including the BEAM, LEED, and BREEAM ranking systems. These standards are mostly concerned with environmental problems and energy consumption and none of them consider building performance assessment with safety, health, environment protection, saving energy, and elegance. Performance criteria ranking with the consideration of conditions governing the studied area enables material producers and suppliers in the building industry construct buildings according to the views on the area to enhance comfort feeling in them. Furthermore, the consideration of safety and health criteria in the material provision, construction, and use processes of buildings may increase the health and safety levels of the construction industry, which is referred to as one of the most dangerous industries. The combination of the HSE criteria with energy, comfort, and elegance is one of the most important practices in the performance assessment of the building industry, which was considered in this study. The determination of their relationships, as well as the effectiveness and susceptibility of each criterion and its sub criteria, can be very essential in building performance control and management, which was considered by this study.
This protocol outlines a comprehensive approach to evaluating hospital solid waste levels and assessing associated health, safety, and environmental (HSE) risks using the Failure Mode and Effects ...Analysis (FMEA) methodology. The study focuses on Imam Khomeini Hospital (RA) and employs both quantitative and qualitative methods. Over a 3-month period, waste production and potential risks are assessed, with specific attention to household, infectious, medicinal, and sharps waste. Through FMEA, potential failure modes and associated risks in waste management sectors are identified, enabling targeted interventions for risk mitigation. The protocol emphasizes the importance of aligning waste management practices with international standards and highlights the need for comprehensive training, awareness campaigns, and effective waste management methods to ensure the safety and environmental responsibility of hospital waste management practices
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The level of contractor’s HSE is a major concern in outsourcing of the works for large organizations. In each tender a rational level of HSE holding by the contractors is recommended to reduce the ...project costs. By investigating the classification procedure of the contracts available in reliable manuals and models at international level, 6 main criteria were selected for determining the contract level from the viewpoint of HSE. Also, an indicator, called "contract separation" was proposed by weighting the criteria. Initial weight of the main criteria along with their scoring in this indicator was determined by applying sub-criteria characteristics, namely "specialized workforce", "man-day required for meeting the criteria", "required technology", and "impact of criterion on planning the next steps of the contract". Then, by preparing a questionnaire and applying the experts' opinion, the final weight of the criteria was specified, based on which all the contracts of Shahid Tondgouyan Oil Refinery Company in Tehran were divided into four levels, namely (1) advanced, (2) moderate, (3) basic, and (4) exempted from the initial HSE assessment. Results of the present study showed that the operational risk level had the highest impact percentage on determining the level of contract compared with other criteria, which indicates that regardless of other criteria, in case the level of contract risk is high, some special HSE measures should be planned for that contract according to the advanced contracts. Also, cost of the contract had the lowest weight; although cost of the contract is one of the most effective criteria in the contract classification, it cannot by itself represent the magnitude of the contract from the HSE perspective and its impact must be considered along with other criteria associated with HSE in order to determine the contract level.
Barnacle growth on seismic streamers creates noise on the recorded signals. Keeping a low noise level in barnacle areas is challenging to seismic crews: Frequent workboat trips are required for ...streamer cleaning, and workboat operations are weather-dependent and considered undesirable from an HSE perspective. In 2007 a purely mechanical and autonomous streamer cleaning unit (SCU) was introduced that is launched and recovered from the workboat. In 2016 we subsequently developed a remotely operated streamer tool (ROST) that is capable of launching and recovering SCUs to/from the streamer without the use of a workboat, and which is therefore less affected by weather. The ROST is operated from a support vessel that is independent of the seismic vessel. We present experiences from four surveys that were subject to different operating conditions. Operation in high sea states is demonstrated on a survey offshore Namibia, and operation in extreme currents is demonstrated on another survey east of South Africa. A noise removal method is also presented that allows operation of the ROST while online during seismic recording. The method was first applied on the offshore South African survey, and later on two surveys in offshore Angola. It is demonstrated that work boat exposure hours can be reduced by 70-80%, and a 14 streamer spread can be cleaned twice a week while acquiring seismic in all types of operating conditions.
We present new whole-rock major and trace element, Re–Os isotope and mineral chemistry data for the upper mantle peridotites and mafic rocks in the Rehafiye ophiolite in NE Anatolia (Turkey), and ...discuss their significance for the mantle evolution in Neotethys. The Refahiye peridotites include clinopyroxene (cpx)-rich and cpx-poor harzburgites. Assuming an initial fertile mantle composition, the cpx-rich harzburgites have a limited range of Cr-spl Cr# (33–38), implying 14–18% melt extraction. However, TiO2 contents of the Cr-spl in these rocks are too high (up to 0.24wt.%) to explain their Ti concentrations with a simple melt extraction model in a mid-ocean ridge (MOR) setting, and suggest re-crystallization from an impregnating fertile melt. The interstitial phases of cpx in these samples have high TiO2 (up to 0.40wt.%) and Na2O (up to 0.25wt.%) contents. They also contain interstitial pargasitic amphibole with TiO2 contents varying between 0.69 and 0.88wt.%. These textures and the mineral chemistry data indicate refertilization of the previously depleted, MOR-type peridotites by percolating hydrous melts. The whole-rock REE partial melting modeling is consistent with slightly lower degrees of mantle melting (~12–14%) compared to the melt extraction degrees obtained from the Cr-spl compositions (~15%). Chromian spinel (Cr-spl) phases in the cpx-poor harzburgites show a wider variation of Cr#, ranging between 57 and 75, and reflect 30–40% of partial melting. In contrast, the whole-rock geochemistry of these rocks represents slightly lower degrees of partial melting, varying between 30 and 35%. The enrichment of TiO2 contents of the Cr-spl (up to 0.20wt.%) in some of the cpx-poor harzburgites can be explained by their interaction with Ti-rich hydrous melt formed at supra-subduction (SSZ) tectonic setting. Highly unradiogenic Os isotope composition (0.11956) of a cpx-poor harzburgite sample suggests an ancient melt depletion event experienced by these rocks, whereas its high Re content is a manifestation of subduction enrichment. The mafic units of the Refahiye ophiolite show MORB-like to island arc tholeiite (IAT) geochemical signatures typical of SSZ oceanic crust. A U–Pb zircon age of 183±1Ma obtained from an isotropic gabbro sample suggests that the crystallization of the SSZ-type mafic units in the Refahiye ophiolite is as old as the early Jurassic.
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•MOR- and SSZ-type peridotites coexist in the Refahiye ophiolite, NE Turkey.•MOR-type depleted peridotites were refertilized by percolating hydrous melts.•Mafic units show MORB-like to IAT geochemical signatures typical of SSZ oceanic crust.•U–Pb zircon age of 183±1Ma from SSZ-type gabbro suggest early Jurassic subduction.
Due to the increasing complexity of optimization problems, distributed differential evolution (DDE) has become a promising approach for global optimization. However, similar to the centralized ...algorithms, DDE also faces the difficulty of strategies' selection and parameters' setting. To deal with such problems effectively, this article proposes an adaptive DDE (ADDE) to relieve the sensitivity of strategies and parameters. In ADDE, three populations called exploration population, exploitation population, and balance population are co-evolved concurrently by using the master-slave multipopulation distributed framework. Different populations will adaptively choose their suitable mutation strategies based on the evolutionary state estimation to make full use of the feedback information from both individuals and the whole corresponding population. Besides, the historical successful experience and best solution improvement are collected and used to adaptively update the individual parameters (amplification factor <inline-formula> <tex-math notation="LaTeX">{F} </tex-math></inline-formula> and crossover rate CR) and population parameter (population size <inline-formula> <tex-math notation="LaTeX">{N} </tex-math></inline-formula>), respectively. The performance of ADDE is evaluated on all 30 widely used benchmark functions from the CEC 2014 test suite and all 22 widely used real-world application problems from the CEC 2011 test suite. The experimental results show that ADDE has great superiority compared with the other state-of-the-art DDE and adaptive differential evolution variants.
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