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The purpose of this paper is to study the effects of fiber length and content on properties of E-glass and bamboo fiber reinforced epoxy resin matrices. Experiments are carried out as per ASTM standards to find the mechanical properties. Further, fractured surface of the specimen is subjected to morphological study.

Composite samples were prepared according to ASTM standards and were subjected to tensile and flexural loads. The fractured surfaces of the specimens were examined directly under scanning electron microscope.

From the experiment, it was found that the main factors that influence the properties of composite are fiber length and content. The optimum fiber length and weight ratio are 15 mm and 16 percent, respectively, for bamboo fiber/epoxy composite. Hence, the prediction of optimum fiber length and content becomes important, so that composite can be prepared with best mechanical properties. The investigation revealed the suitability of bamboo fiber as an effective reinforcement in epoxy matrix.

As bamboo fibers are biodegradable, recyclable, light weight and so on, their applications are numerous. They are widely used in automotive components, aerospace parts, sporting goods and building industry. With this scenario, the obtained result of bamboo fiber reinforced composites is not ignorable and could be of potential use, since it leads to harnessing of available natural fibers and their composites rather than synthetic fibers.

This work enlists the effect of fiber length and fiber content on tensile and flexural properties of bamboo fiber/epoxy composite, which has not been attempted so far.

Natural fiber composites have been proven an alternative to conventional composites in many applications such as automotive and transportation industries owing to their eco-friendliness and abundant availability. Also, they are recyclable and biodegradable. Therefore, the need for composites having superior performance is increasing consistently, which has prompted the research reported in this paper. This paper aims to fabricate and evaluate the properties of hybrid composites using glass and cotton fiber with epoxy resin.

They were prepared by hand lay-up method, using e-glass and cotton fibers. Epoxy resin used in the preparation of composites. The composites were hybridized at two weight percentages (20 and 30 Wt.%). The prepared samples were tested to evaluate its properties, such as tensile strength, flexural strength, impact strength and scanning electron microscope .

Microscopic examination revealed the morphological features. Hybrid fiber reinforced epoxy composite (HFREC) exhibited better mechanical properties than the individual samples. It is clear that 30 Wt.% fraction of fiber is better in mechanical properties than 20 Wt.% fraction of fiber reinforcement in both glass fiber and cotton fiber as reinforcement. Also, the hybridization of fibers resulted in increase in properties.

As cotton fibers are biodegradable, recyclable and lightweight, it has many applications and is mainly used as automotive components, aerospace parts, sporting goods and building industry when reinforced with glass and epoxy. With this scenario, the obtained results of cotton fiber reinforced composites are not ignorable, which could be of potential use, as it leads to better use of available natural fibers.

This work discovered the properties of e-glass and cotton fiber reinforced epoxy resin hybrid composites (hybridized at different weight percentages), which has not been attempted so far.

The purpose of this paper is to identify the ideal process parameters to be set for the drilling of hybrid fibre-reinforced polymer (FRP) (kenaf and banana) composite using High-Speed Steel drill bits (5, 10, 15 mm) coated with tungsten carbide by means of statistical reproduction of the delamination factor and machining force using Taguchi–Grey Relational Analysis.

The contemplated process parameters are Feed, Speed and Drill Diameter. The trials were carried out by taking advantage of the L-27 factorial design by Taguchi. Three factors, the three level Taguchi Orthogonal Array design in Grey Relational Analysis was used to carry out the trial study. Video Measuring System was used to identify the damage around the drill region. “Minitab 18” was used to examine the data collected by taking advantage of the various statistical and graphical tools available. Examination of variance is used to legitimize the model in identifying the most notable parameter.

The optimised set of input parameters were found out successfully which are as follows: Feed Rate: 450 mm/min, Cutting Speed: 3,000 rpm and Drill Diameter of 5 mm. When these values are fed in as input the optimised output is being obtained. From ANOVA analysis, it is apparent that the Speed (contribution of 92.6%) is the most influencing parameter on the delamination factor and machining force of the FRP material.

Optimization of process parameters on drilling of natural fibres reinforced in epoxy resin matrices using Taguchi–Grey Relational Analysis has not been previously explored.

The need for seeking alternate materials with increased performance in the field of composites revived this research, to prepare and evaluate the mechanical properties of e-glass and aloe vera fiber-reinforced with polyester and epoxy resin matrices.

The composites are prepared by hand layup method using E-glass and aloe vera fibers with length 5-6 mm. The resin used in the preparation of composites was epoxy and polyester. Fiber-reinforced composites were synthesized at 18:82 fiber–resin weight percentages. Samples prepared were tested to evaluate its mechanical and physical properties, such as tensile strength, flexural strength, impact strength, hardness and scanning electron microscope (SEM).

SEM analysis revealed the morphological features. E-glass fiber-reinforced epoxy composite exhibited better mechanical properties than other composite samples. The cross-linking density of monomers of the epoxy resin and addition of the short chopped E-glass fibers enhanced the properties of E-glass epoxy fiber-reinforced composite.

This research work enlists the properties of e-glass and aloe vera fiber-reinforced with polyester and epoxy resin matrices which has not been attempted so far.

Climate change presents potential increased threats to the comfort and health of urban populations as a result of higher summer temperatures. This paper reviews recent research on the climate change adaptation potential of urban environments and focuses on a major conurbation, London. Recent work relating to the impact of exposure to heat on population health is also noted. Data obtained from a pilot monitoring study carried out in a subset of 36 dwellings (from a total of 110 dwellings in the overall study) across London during the summer of 2009 is then discussed. Preliminary results illustrate the need to quantify the net impacts of individual building characteristics and the location of each dwelling within the London heat island. During a hot period, more than 40% of the monitored bedrooms failed the recommended overheating criteria during the night time. There was some indication of purpose built flats being more prone to overheating. The potential use of such data as the basis of a heat-related health risk epidemiological model for London is discussed. Such a tool would help health policy makers to target the most vulnerable building types and areas.

Recent climate change projections estimate that the average summertime temperature in the southern part of Great Britain may increase by up to 5.4°C by the end of the century. The general consensus is that projected increases in temperature will render British dwellings vulnerable to summer overheating and by the middle of this century it may become difficult to maintain a comfortable indoor environment, if adaptation measures are not well integrated in the design and operation of new dwellings, which are likely to remain in use beyond the 2050s. The challenge is to reduce overheating risks by integrating building and user adaptation measures, to avoid energy intensive mechanical cooling. Developing guidelines and updating building regulations for adaptation, therefore, requires an understanding of the baseline scenario; i.e. the performance of existing buildings in future climates.

This paper aims to investigate the performance of new-build multi-occupancy British dwellings for human thermal comfort in the present-day and projected future climates in four regional cities: Birmingham, Edinburgh, London and Manchester. Evaluations are carried out by a series of dynamic thermal simulations using widely adopted threshold temperature for overheating, as well as adaptive thermal comfort standards. This study thus offers a unique perspective on regional variations of performance and provides a clearer snapshot because of the use of more appropriate adaptive comfort standards in the evaluations. Finally, the paper sheds light on possible personal and building adaptation measures to alleviate overheating risks.

In recent years, the use of earth as a material applied to construction has been adapted as an attractive alternative to modern concepts. The earth construction technique takes advantage of regional natural resources, among which are earth bricks. The purpose of this paper is to analyze the effect of the addition of coconut fibers and aloe vera on the mechanical properties of compressed earth blocks (CEB).

CEBs were manufactured from silty and clay soil (Altamira, Tamaulipas, Mexico) with biodegradable stabilizers of aloe vera and short coconut mesocarp fibers, which were compared with the conventional mixture with lime as stabilizer. The samples were subjected to compression tests (Mexican Standard NMX-C-404-ONNCC3-205), flexion (NMX-C083-ONNCCE.), abrasion (NTC-5324 3.4.3), water absorption (NMX-C-37-ONNCE-205), surface morphology and thermal properties (ASTM D5334-14).

It was found that the addition of coconut fibers has a 12% difference in flexural strength. The addition of 0.5% of coconut fibers decreases swelling by 2% with water and reduces the thermal conductivity of the material by 12%. Likewise, this mixture increases the abrasion resistance of CEB by 30%. When there is a pressure greater than 1,700 psi in the CEB, the addition of coconut fibers does increase the compressive strength of the material, showing a 34% improvement over the CEB without adding coconut fibers.

The authors show a new sustainable CEB production with aloe vera and coconut fiber that is possible for self-production with better mechanical properties than others, commonly produced in Mexico.

The most difficult tasks in the design and development of products for diverse engineering applications were the selection of suitable materials. Choice of inappropriate process variables leads to poor performance, which increases the cost of the product. The selection of the best option of available alternatives is important to improve the performance and productivity of the manufacturing enterprises.

The paper aims to develop Hybrid Multi-Criteria Decision Making (HMCDM) by integrating two potential optimization techniques Elimination Et Choix Traduisant la REalité and multi-objective optimization on the basis of ratio analysis. The weight of the criteria was calculated using the critic weight method.

The efficiency and flexibility of the proposed HMCDM technique were illustrated and validated by two examples. In the first case, the best electrode material among the five available alternatives was selected for the electrical discharge machining of AZ91/B4Cp magnesium composites. In the second case, the optimum weight percentage of composites providing the best tribological properties was chosen.

It was noted that the HMCDM methodology was quite simple to comprehend, easy to apply and provided reliable rankings of the material alternatives. The proposed hybrid algorithm is suitable for product optimization as well as design optimization.

The aim of this article is to demonstrate the development of environment friendly, low cost natural fibre composites by robust engineering approach. More specifically, the prime objective of the study is to optimise the composition of natural fibre reinforced polymer nanocomposites using a robust statistical approach.

In this research, the material is prepared using multi-walled carbon nanotubes (MWCNT), Cantala fibres and Epoxy Resin in accordance with the ASTM (American Society for Testing and Materials) standards. Further, the composition is prepared and optimised using the mixture-design approach for the flexural strength of the material.

The results of the study indicate that MWCNT plays a vital role in increasing the flexural strength of the composite. Moreover, it is observed that interactions between second order and third order parameters in the composition are statistically significant. This leads to proposing a special cubic model for the novel composite material with residual analysis. Moreover, the methodology assists in optimising the mixture component values to maximise the flexural strength of the novel composite material.

This article attempts to include both MWCNT and Cantala fibres to develop a novel composite material. In addition, it employs the mixture-design technique to optimise the composition and predict the model of the study in a step-by-step manner, which will act as a guideline for academicians and practitioners to optimise the material composition with specific reference to natural fibre reinforced nanocomposites.

This study presents findings of post-occupancy evaluation (POE), through a performance assessment, on a polyclinic, as a health-care facility, in Saudi Arabia.

Review of the literature is conducted to identify the recent publications, on conducting POE, and performance indicators (PIs) assessing performance of health-care facilities. This research uses a triangulated approach by adopting several qualitative and quantitative methods, on a case study. The approach comprised conducting investigative walkthrough to assess the case study facility, interviews with group of occupants to assess its satisfaction levels. The findings were presented to a focus group, where a plan of recommendations was raised to improve the performance of the case study facility.

A total of 24 PIs were identified, and clustered, mainly under: “Thermal comfort”, “Natural lighting”, “Artificial lighting” and others. The case study has proven a satisfactory performance to the evaluated indicators. However, observations of performance snags were identified that formulated conclusions, related to: “Improvements to air temperature performance in summer season”, “Need of control on natural lighting due to glare”, “Accommodating an over demand for car parking spaces”, Need for development of systems dedicated for collection of occupants satisfaction” and “Enhancing circulation”.

There is a gap identified, through the literature review on availability of systematic conduct of POE, especially in health-care facilities. This paper contributes to the body of knowledge and professional practice, as a guiding systematic scheme, for the conduct of POE, which can be followed and expanded upon by future research.