This study aims to find the specification of textbook material for grade 1 Madrasah Ibtidaiyah (MI) in Salatiga City. This study used descriptive qualitative and descriptive quantitative approaches. ...A qualitative descriptive approach was employed to describe the data obtained through the interview method, with the type of guided interview. The interview method used an interview guide instrument, analyzed through the stages of analyzing data, reducing data, categorizing data, interpreting data, and drawing conclusions. Meanwhile, a quantitative descriptive approach was utilized to describe the data obtained through a questionnaire, which used a filling type questionnaire. Questionnaire data were then analyzed using descriptive statistical formulas. The study results found that the material specifications for the MI grade 1 textbook in Salatiga City had been adjusted to the core competencies (KI) and basic competencies (KD) set by the government; the development of the material was sourced from information technology that can be accounted for and from similar books; the material was adapted to the students' abilities; the material was adapted to the conditions of the student's cultural environment; the material paid attention to the condition of student diversity; the material contains factual truths and concepts; supporting learning; the material begins with question and command sentences. The theoretical implication of this finding is that it can be used as a reference in assessing and developing textbooks at MI.
Nanomaterial testing standards play a crucial role in the international standardization of nanotechnology within ISO. These standards specify the characteristics of nanomaterials that need to be ...measured, as well as the methods and procedures used for conducting such measurements. This paper presents a methodology for the development of nanomaterial testing standards, which addresses raw nanomaterials and intermediate materials like composites, suspensions, films, and coatings containing raw nanomaterials. The methodology is outlined as a scenario comprising several stages towards the goal, where essential actions to be conducted in standardization are identified and integrated into the standard. Furthermore, this paper highlights the significance of these testing standards as a technical foundation for material specification and certification, with the ultimate aim of facilitating the industrialization of nanomaterials by ensuring consistent quality and enabling reliable performance.
AbstractThis paper presents an experimental study that investigated the physical, mechanical, and durability characteristics of three different types of fiber-reinforced polymer (FRP) bars made of ...basalt and glass fibers with vinylester and epoxy resins, namely basalt/vinylester (B/V) FRP bars, glass/vinylester (G/V) FRP bars, and basalt/epoxy (B/E) FRP bars. First, their physical and mechanical properties were assessed. Then, a comparative durability study was performed on the three types of FRP bars under alkaline exposure simulating a concrete environment. The alkaline exposure was achieved by immersing the bars in an alkaline solution for up to 5,000 h at 60°C. Thereafter, the properties were assessed and compared with the unconditioned (reference) values. The test parameters were (1) fiber type (basalt or glass); (2) resin type (vinylester or epoxy); and (3) conditioning time (1,000, 3,000, and 5,000 h). The test results reveal that the G/V composite had the best physical and mechanical properties and lowest degradation rate after conditioning in alkaline solution. The B/E composite ranked second, while the B/V composite evidenced the lowest physical and mechanical properties and exhibited significant degradation of its physical and mechanical properties after conditioning.
•Physical and mechanical characterization of newly developed basalt FRP bars for concrete members.•Durability of BFRP bars in harsh alkaline conditions simulating the concrete environment.•Discussion ...of BFRP characterization and durability results and compare them against the requirements of FRP standards.
This paper introduces an experimental study that investigated the physical, mechanical, and durability characteristics of basalt fiber-reinforced polymer (BFRP) bars. Durability and long-term performance were assessed by conditioning the BFRP bars in an alkaline solution simulating the concrete environment (up to 3000h at 60°C) to determine their suitability as internal reinforcement for concrete elements. Thereafter, the properties were assessed and compared with the unconditioned (reference) values. In this study, three types of BFRP bars were investigated. The test results revealed that the BFRP bars had good mechanical behavior and could be placed in the same category as grade II and grade III GFRP bars (according to tensile modulus of elasticity). Their tensile strength, however, was higher than that provided by CAN/CSA S807-10 for CFRP bars. On the other hand, the BFRP bars showed poor alkali resistance and exhibited a remarkable reduction in mechanical properties due to the resin–fiber interface issues, which needs to be remedied to achieve the desired durability characteristics.
•Architect perceptions of engineered wood products in Europe countries were studied.•A positive perception regarding the use of wood in general in all countries.•A lack of knowledge of principles of ...design options with EWPs.•The internet is the leading source of information used by architects.•There is a need for more technical information to understand the potential of EWPs.
The wood industries in Slovenia, Croatia, Bosnia and Hercegovina (BiH) and Macedonia have a long tradition of producing a wide range of products. BiH and Macedonia have similar forest sectors and both countries have experienced similar problems in the manufacturing, sale and use of wood-based products in recent years due to the global financial crisis and resulting national economic challenges. Despite having a long and prosperous history, over the past two decades, the wood products sectors in these four countries have faced a steady decline in profitability, the ability to add value through downstream manufacturing, and overall competitiveness.
Engineered wood products (EWPs) are structural building materials that have been used since the early 1980s as replacements for, or in conjunction with, concrete and steel. In this study, we compare architect attitudes, awareness and preferences regarding the use of EWPs between these four countries. The study is based on a sample of 373 architects using on-line surveys. Results suggest that there is a positive perception regarding the use of wood in general in all countries, with the majority of respondents believing that wood use will increase in the future. However, specific to EWPs, differences were found in familiarity and knowledge of potential applications in timber-based construction. Results provide indicators of knowledge gaps between respondents and, conversely, where awareness and willingness to use EWPs exist. These findings can have implications for market opportunities, identifying barriers to EWPs adoption, and content for workshops, seminars, and other outreach mechanisms for architects.
From a climate perspective, it could be advantageous to increase the use of wood products in buildings, but the use of sawn timber and engineered wood products (EWPs) in multi-storey buildings above ...two floors are a relatively new business (in Sweden since 1995) and there is a risk that wood as construction material is met with low awareness and high uncertainty by the construction sector. The purpose of this study was twofold: 1) to learn Swedish architects' views of using EWPs in buildings, and 2) to identify parameters that positively influence the likelihood that EWPs will be selected to a greater extent and the relative importance of those parameters.
A survey was sent out to Swedish architects and 67 answers were received. The result indicates that architects in Sweden have a positive attitude towards EWPs in general and that the majority think that they will probably increase their use of these materials. Low impact on the environment, aesthetic appeal, and fast construction were the most common reasons stated for selecting EWPs. The Swedish architects have in general a moderate impact on the selection of materials, and the most common reason for not selecting EWPs was that other decision makers involved in the building projects prefer other materials. A lack of knowledge and information as well as uncertainties regarding the quality over time were other common reasons for not selecting EWPs.
It was found that architects who had participated in building projects where EWPs had been chosen due to their low environmental impact and/or aesthetic appearance were more likely to state that they will increase their use of EWPs. The results also show that influence on material selection, knowledge of EWPs, experience of the use of EWPs, and the architect's own attitude to the use of EWPs affect the likelihood of an increased use.
•Swedish architects have potential to be good advocates for increased use of EWPs.•Supposedly low environmental impact - most common reason for selection of EWPs.•Other actors prefer other materials – most common reason for not selecting EWPs.•There is a need to increase the architects' knowledge of engineered wood products.
In order to solve the problems existing in airworthiness verification of the large integral metallic structure for civil aircraft main bearing part, the airworthiness verification of the metallic ...structure additive manufacturing technology was carried out. Through the analysis of applicable airworthiness clauses of additive manufacturing technology, the general idea of airworthiness verification of the metallic structure additive manufacturing technology of civil aircraft is given, including the establishment of material specification, the determination of material strength properties, the selection of structural special factor, and the verification of structural performance. Each verification method gives a specific implementation approach. Taking outer cylinder of the nose landing gear pillar which is made by additive manufacturing technology with A-100 ultrahigh strength steel as an example, a specific implementation plan for airworthiness verification of additive manufacturing technology for large integra
Based on years of airworthiness regulations research, combined with the experience of airworthiness certification of civil aviation products, the airworthiness requirement to materials for civil ...aviation products was analyzed. The key airworthiness requirement for materials is that materials should conform to some material specification to ensure their having the strength and other properties adopted in the design data. The shortcomings of domestic airworthiness management methods for civil aviation materials was discussed and three recommendations for improvement were proposed:(1) conduct individual airworthiness management for civil aviation materials according to CCAR 21.351 through 371 and CCAR 37; (2) develop and promote statistical-based material specification developing methods, to establish material specifications which could ensure material having the strength and other properties adopted in the design data; (3) establish a cooperation mechanism for developing material design value data base for civi
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