Dimensional Attributes Research Articles

Exploring the mechanical and thermal properties of rubber-based nanocomposite: A comprehensive review

Abstract The emergence and progression of synthetic rubber have paved the way in variegated prospects across various engineering and technological fields. Nonetheless, its inherent limitations such as poor mechanical and thermal properties including wear resistance, poor tensile strength, and lower thermal conductivity, as evident in styrene butadiene rubber and silicone rubber, have constrained its utility in numerous load-bearing scenarios. This limitation has been addressed by incorporating specific nanofillers into various rubber compositions, resulting in promising outcomes up to a certain threshold. Many nanofillers were trialed, such as graphite oxide, aluminum oxide, carbon nanotubes, and boron nitride. However, an attempt should be made to explore the disparity in dimensional attributes of nanofillers and their effect on different properties of rubber, thereby delineating the scope for future research. The exploration of dimensionally distinct nanofillers, such as 1D multiwalled carbon nanotubes and 2D graphene, can overcome these limitations and augment rubber’s mechanical properties and thermal properties. The study also delineates the scope of future research, which should be focused on optimizing the nanofillers’ dispersion and interfacial bonding within the rubber matrix by trying dimensionally different nanofillers.

Why should eventfulness be replaced with arousal in the Perceived Affective Quality Scale for soundscape research?

The two attributes "eventful" and "uneventful" are proposed for those evaluating the perceived affective qualities of soundscapes in ISO/TS 12913-2. In this paper, from two points of view, the reasons why those attributes should be replaced with those regarding arousal are discussed. From the viewpoint of psychology, affective quality is defined as the ability to cause a change in core affect and, therefore, can be describable in terms of the same two dimensions as core affect. On the other hand, "eventful" and "uneventful" are not affective but cognitive attributes. It is a theoretical mistake to term different dimensional attributes as affective ones. From the viewpoint of translatability, the Japanese-translated word for "uneventful" cannot be distinguished from those for "calm." This fact suggests that at least one culture exists in which the semantic difference between "uneventful" and "calm" is not essential. For those in a culture where the semantic difference between two attributes is not essential, it is natural that the evaluation using those attributes is also inessential. The scales proposed in the international standards should be meaningful beyond the cultures. From this perspective, we can say that "uneventful" is not the appropriate attribute for using ISO standards.

Memorable experiences and their influential factors: an importance-performance analysis of a cultural event

ABSTRACT This study aimed to verify the underlying influential factors of cultural event attributes and proposed a structural model to examine the event dimensions that influence attendees’ memorable experiences and subsequent life satisfaction and sharing experiences. Partial least squares structural equation modelling (PLS-SEM) was used to analyse the proposed conceptual model with data obtained from 756 respondents. The results indicated that activities, uniqueness, distinctiveness and authenticity had strong and positive effects on memorable experiences, which, in turn, impacted life satisfaction and sharing experiences via social media. An in-depth examination through importance – performance map analysis (IPMA) revealed the prioritisation of crucial event dimensional attributes.

Sexual objectification versus empowerment: Examining the effects of sexualized women’s facial expression on viewers’ evaluations of social cognition and self-objectification

Objectification scholarship highlights how traditional media portrayals oftentimes direct attention toward women’s bodies and away from their faces which communicate important social information. This study sought to investigate how thin-ideal, white women’s facial expression potentially attenuates the negative effects of appearing in a sexually objectifying manner using validated imagery. In a 2 × 3 between-subjects experiment (N = 1001 U.S. adult women; Mage = 42.56, SDage = 12.72), portraits of women varied in their sexualization (non-sexualized vs. sexualized) and facial expression (neutral expression, low-intensity smiling, high-intensity smiling) to better understand how these factors influence dimensions of social cognition (competence, warmth, authenticity), self-promotional attributions, and viewers’ own self-objectification. Results revealed that viewers rated sexualized (vs. non-sexualized) women lower in competence and authenticity, as well ascribed more self-promotional explanations for their behavior. Moreover, exposure to sexualized women heightened viewers’ self-objectification, regardless of facial expression. Results also indicated that smiling intensity positively influenced viewers’ ratings of social cognition. However, there is little evidence that smiling intensity overrides the negative effects of sexualization. Implications for the sexual objectification of women are discussed.

Perceptions of Halal-friendly attributes: a quantitative study of tourists’ intention to travel non-Islamic destination

PurposeThailand's Halal-friendly destination attributes are the focus of this study. The purpose of this study is to investigate the impact of Halal-friendly attributes on tourists’ intentions to visit non-Muslim destinations. Also, this study analyzes the impact of Muslim tourists’ attitudes on Halal-friendly characteristics and their intentions to visit countries that are not predominantly Muslim.Design/methodology/approachTo accomplish objectives, a survey was used to gather the data by using a convenient non-probability sampling approach from Muslim-majority countries Malaysia, Indonesia and Brunei. A proposed structural equation model was used to assess the influence of the variables above on the outcomes.FindingsThis study found that the factors of Halal-friendly facilities and Halal-friendly service positively influence the visiting intentions of Indonesian, Malaysian and Brunei Muslim tourists. In contrast, the social environment, food/beverages and local and staff attributes do not influence visit intentions. The tourist attitude mediates the relationship between the intention to visit and three dimensions of Halal-friendly attributes (social environment; food/beverage; and locals and staff).Research limitations/implicationsThis study did not investigate different kinds of dimensions for Muslim tourists visiting Thailand, such as preferences regarding personnel and families, cultural and artistic characteristics and the attributes of events and festivals. These dimensions cover a wide range of Halal-friendly tourism aspects. Second, this research did not investigate the associations between the demographics of Muslim tourists (age, gender, education level and income level) and the model variables. Such an investigation could have helped business developers and marketers in Thailand develop an efficient strategy for target marketing. The results of this research provide fundamental guidance and information for tourist enterprises in non-Muslim nations on how to enhance Muslim travellers’ images and intentions. However, because of the influence of other variables, locations in various areas of Asia, Africa and Europe may exhibit somewhat different effective qualities (e.g. environment, culture, history, etc.).Practical implicationsThis study sheds light on the factors contributing to visitor satisfaction in the context of a desire to go to a Halal-friendly site. This insight from this study can be adapted and applied by tourism managers and marketing executives to build or develop the Halal-friendly destination image of a tourist destination (Phuket) in the right dimensions. It is a possibility that the image of a tourist attraction has a tight relationship with travelers’ perceived value, contentment and loyalty (Hsu et al., 2008; Khunrattanaporn, 2013; Pike, 2008). Battour et al. (2022) found that Muslims’ behavioural intentions are affected by the Halal attributes of the destination. It indicates that Halal attributes are very important for Muslim tourists when selecting a destination. To attract Muslim tourists, this study can be used for strategies and planning.Originality/valueThis study sheds fresh light on the concept of Halal tourism. It examines the perspective of Muslim tourists using Halal goods or services in anticipation of a future trip to a non-Muslim location (Phuket). This study is crucial for destination tourism operators, managers and marketers who lead Muslim tourists to non-Muslim destinations.

Mechanical characterization of PEEK-CF/PEEK sandwich structures prepared via a combination of fused filament fabrication and epoxy post-bonding

Poly-ether-ether-ketone (PEEK) and carbon-fiber-reinforced PEEK (PEEK-CF) are examples of engineering thermoplastics with exceptional mechanical properties. In the context of Fused Filament Fabrication (FFF), the interlayer bonding between PEEK and PEEK-CF has a significant impact on the mechanical properties of printed components. Epoxy resin is used to enhance the interfacial bonding between PEEK and PEEK-CF due to its remarkable adhesive properties, while preserving the dimensional and weight attributes of the bonded sandwich structure. The application of epoxy resin as a post-processing technique enables the creation of intricate geometric designs within the bonded sandwich structures. This study presents a straightforward technique for producing sandwich structures using PEEK and PEEK-CF, followed by improving their mechanical properties through isothermal annealing. We conduct systematic single-factor experiments to explore the mechanical advantages of FFF-printed PEEK and PEEK-CF via three-point bending tests on individually printed monolithic specimens. Furthermore, mono-material specimens are bonded using epoxy resin to form dual-material bending specimens. Our findings reveal an optimal sequence: after isothermal annealing, mono-material specimens bonded with epoxy resin exhibit superior flexural strength and modulus. In addition, an in-depth examination of the meso-structure and fracture morphology of FFF-printed sandwich structures after bonding and heat treatment reveals insights into toughening and reinforcement mechanisms. This analysis is complemented by corresponding finite element simulations to validate the results. Notably, our research highlights the successful optimization of interlayer structures, facilitating the creation of sandwich structures with superior mechanical performance.

Visitors’ perceptions of urban wilderness. A case study of Jiangyangfan Ecological Park in Hangzhou, China

Numerous studies show the benefits of wilderness to humans and the environment. Therefore, preserving and developing wilderness areas within urban settings are crucial to combat and mitigate challenges like biodiversity decline resulting from urbanization. According to previous studies, human-wilderness interactions can be contradictory, e.g., relaxing while feeling anxious and insecure. How individuals perceive and comprehend intentional urban wilderness, what dimensions contribute to their perceptions, and how these dimensions influence the visitors’ perceptions remain to be investigated. Selecting Jiangyangfan Ecological Park (Hangzhou, China) as a survey case, this research investigates if and how people perceive intentionally incorporated and designed urban wilderness and how various dimensions of attributes shape their perceptions. This study identified three dimensions that may contribute to visitors’ perceptions of the urban wilderness; namely, cognitive landscape attributes, perceived environmental attributes, and their visitation experience. A mixed-method approach was employed using a questionnaire, mental maps, and environmental behaviour observation as diverse data sources to assess visitors’ urban wilderness perceptions and comprehension from the three dimensions. Results indicate a high propensity to visit the park as an urban wilderness. Our findings also revealed that visitors' perceptual environmental attributes, e.g., the existence of vegetation and waterbodies and encounters with wild animals, as well as their visit experiences, e.g., their satisfaction with the visit and their motivation for experiencing nature, significantly influence their perceptions. In contrast, prior knowledge and experience-based cognition of urban wilderness attributes showed no significant influence on their perceptions. Moreover, attributes like plant diversity, water visibility, and plant density emerged as critical factors shaping visitors’ perceptions. These findings underscore the importance of considering visitors’ on-site perception of environmental attributes and actual visit experience when assessing the value and acceptability of urban wilderness areas. Future implications of this study for urban wilderness planning and management were also discussed.

The different impact of utilitarian and hedonic attributes on web-based retail shopping behaviour through the lens of extended technology acceptance model

PurposeAcknowledging previous scholarly focus on functional attributes in understanding technology acceptance behaviour, the current study aims to offer a novel perspective by integrating eight different dimensions of utilitarian and hedonic attributes to examine their influence in delivering a holistic web-based retail shopping experience.Design/methodology/approachThe research model was tested and validated through data collected from 370 online shoppers across both hedonic and utilitarian product ranges. Hypotheses were tested using covariance-based structural equation modelling with multi-group analysis to examine the moderation effect.FindingsThe findings strongly support the model confirming eight new utilitarian and hedonic dimensions that influence web-based retail shopping behaviour. The findings also confirm that hedonic attributes remain important even for utilitarian product purchasing.Practical implicationsThe key managerial implication is the demonstrated need to balance utilitarian and hedonic attributes in web-based retail platforms, where previously, there has been an overemphasis on functional features. Web-based retailers should consider the optimal blend of utilitarian (e.g. information quality) and hedonic (e.g. aesthetic) attributes in the design of a retail shopping site, irrespective of the product category.Originality/valueThis study integrates multiple dimensions of utilitarian and hedonic attributes into a single model and highlights the interplay of these attributes, thus extending the technology acceptance model. This paper also advances scholarship through its identification of attribute impact across different product categories.

Physico-Mechanical Properties of Pumpkin Seeds in the Context of Drying Processes

The paper highlights the significance of the drying process in post-harvest cucurbit seed treatment technology. To improve the effectiveness of drying high-moisture seeds, a plant construction design was introduced, incorporating the concept of providing varied heat distribution to a vigorously agitated seed layer. The paper validates the necessity of refining the dimensional, frictional, and aerodynamic properties of pumpkin seeds to determine the optimal operating modes for the proposed dryer. (Research purpose) To identify the physical and mechanical properties of pumpkin seeds by defining their dimensional, frictional and aerodynamic characteristics. (Materials and methods) The study employs one-factor experimental research methods with subsequent statistical data processing. An experimental study was conducted on the physical and mechanical properties of Volzhskaya Grey pumpkin seeds possessing a standard moisture content ranging between 9.3 and 9.7 percent. Well-known laboratory apparatuses, namely the «conical tank» and the «inclined plane», were used to determine the natural repose angle and to enhance the accuracy of friction coefficients determination. For analyzing the aerodynamic properties of the seeds, the K-293 Petkus air separator was employed. (Results and discussion) Research methods were developed and experimental plants were described. It was established that with a probability confidence level of 0.95, the static friction coefficients of pumpkin seeds on a solid steel sheet, a perforated steel sieve and on rubber are 0.473, 0.418, 0.481, respectively, and the dynamic friction coefficients under the identical conditions are measured as 0.331, 0.293, 0.337. The average angle of natural repose is found to be 22 degrees, the midsection area is 97.94 square millimeters, the soaring velocity is 7.083 meters per second, the windage coefficient stands at 0.196 and the aerodynamic drag coefficient is 0.136. (Conclusions). The assumption that enhancing the drying efficiency of vegetable seeds can be achieved by implementing a diverse thermal energy supply to continuously moving mass inside the apparatus is confirmed, provided that the seeds do not stick together in layers resulting in blockage of the coolant flow. An improved design of the dryer configurations has been developed and, to validate its optimum design and technological specifications, an in-depth analysis of the seeds' dimensional, frictional, and aerodynamic attributes has been conducted.

Analysis of residential satisfaction in the conversion of Beijing’s stock buildings into rental housing

This paper investigates the residential satisfaction levels of tenants living in rental housing converted from non-residential stock buildings in Beijing. A stratified random sampling method was used to select 353 tenants from five apartments based on the plan form and location of the units for a structured questionnaire survey. The results of a hierarchical regression analysis indicated that subjective attributes were more influential in determining residential satisfaction than the objective physical and demographic attributes of the apartments. Within the five dimensions of subjective attributes, the "interior space" dimension had the greatest impact on predicting residential satisfaction. In addition, a one-way ANOVA analysis showed that the floor plan of the apartments also played a significant role in determining residential satisfaction, S-type and office park-type (Converted from an office park) layouts received the highest satisfaction ratings. This research provides valuable insights for revitalizing non-residential stock buildings and offers theoretical support for converting more non-residential stock buildings into rental housing in the future.

A Conceptual Review of Uniform Wear Attributes Identification for Size Fit

With the accessibility of fast fashion, consumers have opportunities to purchase fashion clothes that are current trends, besides providing them options to choose the right garment at any time and place. However, dissatisfaction with garment fit has always been a challenge. Size fit provides a good fit, emphasizing comfort, ease of wearing, and shape. This research has conceptualized several attributes that could enhance the excellent fit of uniform wear that are divided into functional, aesthetic, and emotional. Employing dimensional attributes would enhance the performance of workwear besides pleasing the wearers due to comfort and making them look attractive.

Validation of a Chinese Positive Youth Development Scale: Dimensionality and factorial invariance.

For a multi-dimensional measure of positive youth development (PYD), its factor structure should be invariant across groups and over time. This study examined the factorial validity of the 44-item short form of the "Chinese Positive Youth Development Scale" (CPYDS-SF) that assesses 15 dimensions of PYD attributes. Using two waves of longitudinal data with a one-year interval in between, this study examined the factor structure of the scale and whether the structure is invariant between gender groups and across time. The data were collected from 3,328 adolescents at Wave 1 and 3,638 adolescents at Wave 2, with a matched sample of 2,905 adolescents (mean age = 12.57 ± 0.72 at Wave 1; 49.54% girls). Confirmatory factor analysis revealed that the 15-factor structure fitted the data well. The findings of invariance tests further supported this structure's invariance across gender and time, indicating a stable factor structure of CPYDS-SF among Chinese adolescents. These findings suggest that CPYDS-SF can be used to examine gender differences and the longitudinal development of PYD qualities among Chinese adolescents.

External and Internal Attribution in Human-Agent Interaction: Insights from Neuroscience and Virtual Reality

Agents are designed in the image of humans, both internally and externally. The internal systems of agents imitate the human brain, both at the levels of hardware (i.e., neuromorphic computing) and software (i.e., neural networks). Furthermore, the external appearance and behaviors of agents are designed by people and based on human data. Sometimes, these humanlike qualities of agents are purposely selected to increase their social influence over human users, and sometimes the human factors that influence perceptions of agents are hidden. Inspired by Blascovich’s “threshold of social influence’, a model designed to explain the effects of different methods of anthropomorphizing embodied agents in virtual environments, we propose a novel framework for understanding how humans’ attributions of human qualities to agents affects their social influence in human-agent interaction. The External and Internal Attributions model of social influence (EIA) builds on previous work on agent-avatars in immersive virtual reality and provides a framework to link previous social science theories to neuroscience. EIA connects external and internal attributions of agents to two brain networks related to social influence. the external perception system, and the mentalizing system. Focusing human-agent interaction research along each of the attributional dimensions of the EIA model, or at the functional integration of the two, may lead to a better understanding of the thresholds of social influence necessary for optimal human-agent interaction.

Reaction of Expectation of Success and Failure Attribution among Indian College Adults

The present study is an attempt to investigate reactions to Expected Success followed by Success/Failure feedback (ESS/ESF) in the hypothetical setting. Investigated the effects of personality variable, namely, self-esteem, a cognitive variable, namely, confirmation (actual success, when success was expected) and disconfirmation of expected success, (actual failure, when success was expected), as well as the sequence of these two events, on attribution of Success/Failure along with a social variable, namely, working in an individual or group setting, on reactions to success/ failure. 129 participants were employed through random sampling. The main dependent variables were (a) Subsequent choice of Individual setting/ Group setting, and (b) Attribution of Success/Failure. Subjects, classified into High / Low on Self-esteem (SE), initially expected success working with Group or Individual condition followed by success / failure. They were then asked to make attributions for their unexpected/expected success/failure, and choose an individual and group condition for the next trial. Findings indicated that after individual/ESF and group/ESS, HSE preferred to remain in the same condition. In contrast LSE preferred both conditions equally likely. There were significant differences between Success and Failure conditions with respect to the Attribution dimensions. This line of results supported the cognitive explanation of attribution.

Soundscape Perception and Preference in the context of Malaysian Urban Parks

Park soundscape studies are receiving increasing attention in cities due to the increasing noise pollution in urban centers. As soundscape is dependent on people-place-interaction, there is still a lack of knowledge on how the socio-demography of the park users influences the perceptions and preferences of the soundscapes in the parks of Malaysia. Most studies on soundscape perception are linked to the general population in developed Western and Eastern countries, investigating the relationship of perception with mental well-being. This paper addresses the gap between the park’s sound profile and soundscape perception in the context of a developing country, Malaysia. A random sampling of 423 park users in four selected Kuala Lumpur and Putrajaya parks was used to conduct an on-site survey regarding their perceptions of the park’s soundscape. The study revealed that soundscape perception differs among park visitors in a typical urban park in Malaysia. Three dimensions of socio-demographic and behavioural attributes were found to be associated with the perception and preferences of park soundscapes, which are (1) age and educational level, related to the perception of the dominance of human sounds; (2) distance from home and sensitivity of park users revealed that those who are stressed and more sensitive to noises influence their expectations of the pleasantness and calmness of the park’s soundscape; and (3) gender and occupation on the other hand only relates to the dominance of natural sounds indicating that females are more sensitive to the sounds of nature when in a park. It is crucial to consider the needs of all park visitors to provide a supporting soundscape which matches the activities carried out in the parks. These results implicate Malaysian park planning and management by serving a further understanding of the relationship between the soundscape of the parks from the perspective of different park users.

Construction of High Accuracy Machine Learning Interatomic Potential for Surface/Interface of Nanomaterials-A Review.

The inherent discontinuity and unique dimensional attributes of nanomaterial surfaces and interfaces bestow them with various exceptional properties. These properties, however, also introduce difficulties for both experimental and computational studies. The advent of machine learning interatomic potential (MLIP) addresses some of the limitations associated with empirical force fields, presenting a valuable avenue for accurate simulations of these surfaces/interfaces of nanomaterials. Central to this approach is the idea of capturing the relationship between system configuration and potential energy, leveraging the proficiency of machine learning (ML) to precisely approximate high-dimensional functions. This review offers an in-depth examination of MLIP principles and their execution and elaborates on their applications in the realm of nanomaterial surface and interface systems. The prevailing challenges faced by this potent methodology are also discussed.

41 High Stress and Negative Attributional Style is Associated with Depression Symptoms in Multiple Sclerosis

Objective:Depression is highly prevalent in persons with multiple sclerosis (pwMS). A reformulated version of the learned helplessness theory posits that individuals who attribute the cause of negative events to personal factors (internal), perceive that the cause persists for a long period of time (stable), and believe it is present in all situations (global) are at an increased risk for depression. As such, it is critical to examine possible modifiable factors that buffer against the deleterious effects of negative attributional style. Therefore, the current study investigated whether stress moderates the relationship between negative attributional style and depression symptoms in an MS sample.Participants and Methods:Thirty-six pwMS (30 Female, 6 Male) completed a comprehensive neuropsychological test battery and psychosocial questionnaires that assessed cognitive attributional style, daily stressors, and depression symptoms. The Attributional Style Questionnaire (ASQ) was used to create internal, stable, and global attribution dimension scores, as well as an overall attributional style score combining the three dimensions. Stress was quantified as the total score of perceived hassles from the Hassles and Uplifts Scale (HUS). Depression symptoms were measured using the Beck Depression Inventory-Fast Screen (BDI-FS). Hierarchical linear regressions were conducted with depression symptoms as the outcome variable. Each dimension of attributional style (internal, stable, global, or overall ASQ), stress, and their interactions were included as predictors. Simple effects tests were used to clarify the pattern of any significant interaction.Results:Regression analyses revealed that the interaction between overall attributional style and stress was significant (p = .025). Simple effects tests revealed that overall attributional style was associated with depression symptoms only in pwMS with high levels of stress (p = .015). For the individual dimensions of the ASQ, several interactions were also significant. The interaction between the internal dimension and stress was significant (p= .009), such that internal attributions were associated with depression symptoms only in pwMS with high levels of stress (p = .002). The interaction between the stable dimension and stress was also significant (p = .01); stable attributional style was associated with depression symptoms only in pwMS with high levels of stress (p = .009). The interaction between the global dimension and stress was not significant.Conclusions:Stress moderated the relationship between negative attributional style and depression symptoms in pwMS. Specifically, the internal and stable dimensions and overall attributional style were associated with increased depression symptoms only in pwMS who reported high levels of stress, but not in those with low levels of stress. Interventions aimed at reducing and managing stress may help protect against the effects of negative cognitive schemas on depression symptoms in MS. Additionally, previous research demonstrates that attributional style may be a malleable target of evidence-based psychotherapy (Seligman et al., 1988; Proudfoot et al., 2009). Our findings suggest that cognitive therapy specifically targeting the internal and stable dimensions of attributional style may be effective in modifying attributional style, perceptions of stress and, subsequently, improve depression outcomes in MS.

A New Remote Sensing Service Mode for Agricultural Production and Management Based on Satellite–Air–Ground Spatiotemporal Monitoring

Remote sensing, the Internet, the Internet of Things (IoT), artificial intelligence, and other technologies have become the core elements of modern agriculture and smart farming. Agricultural production and management modes guided by data and services have become a cutting-edge carrier of agricultural information monitoring, which promotes the transformation of the intelligent computing of remote sensing big data and agricultural intensive management from theory to practical applications. In this paper, the main research objective is to construct a new high-frequency agricultural production monitoring and intensive sharing service and management mode, based on the three dimensions of space, time, and attributes, that includes crop recognition, growth monitoring, yield estimation, crop disease or pest monitoring, variable-rate prescription, agricultural machinery operation, and other automatic agricultural intelligent computing applications. The platforms supported by this mode include a data management and agricultural information production subsystem, an agricultural monitoring and macro-management subsystem (province and county scales), and two mobile terminal applications (APPs). Taking Shandong as the study area of the application case, the technical framework of the system and its mobile terminals were systematically elaborated at the province and county levels, which represented macro-management and precise control of agricultural production, respectively. The automatic intelligent computing mode of satellite–air–ground spatiotemporal collaboration that we proposed fully couples data obtained from satellites, unmanned aerial vehicles (UAVs), and IoT technologies, which can provide the accurate and timely monitoring of agricultural conditions and real-time guidance for agricultural machinery scheduling throughout the entire process of agricultural cultivation, planting, management, and harvest; the area accuracy of all obtained agricultural information products is above 90%. This paper demonstrates the necessity of customizable product and service research in agricultural intelligent computing, and the proposed practical mode can provide support for governments to participate in agricultural macro-management and decision making, which is of great significance for smart farming development and food security.

Tensile Properties of 3D Printed Recycled PLA Filament: A Detailed Study on Filament Fabrication Parameters

Polylactic acid (PLA), a biodegradable and biocompatible thermoplastic commonly utilized in 3D Printing filaments, undergoes changes in properties upon recycling. The objective was to elucidate the role of extrusion temperature and screw speed in modulating the quality of recycled PLA filament, as well as in controlling its dimensional attributes. Recycled PLA pellets (3D850D) were extruded using a single filament extruder machine within an extrusion temperature range of 145°C to 165°C and a screw speed varying from 2 rpm to 6 rpm. The extruded filaments were subsequently 3D printed into specimens adopting a 0° raster angle, line infill pattern, and a 100 percent infill density, then tested as per ASTM D638 mechanical standards. The study revealed a profound influence of extrusion parameters on the filament's ultimate tensile strength, yield strength, and diameter. Optimal extrusion conditions - 155°C and 5 rpm - resulted in maximum mechanical strengths, while the parameters yielding filament diameters closest to commercial standards were identified as 5 rpm and 155°C. These results under-score the possibility of optimizing the recycled PLA filament's properties through adept control of extrusion parameters. Consequently, this investigation supports the potential use of recycled PLA filament in the 3D printing industry as a sustainable and performance-efficient material, offering a tangible step towards environmentally friendly additive manufacturing practices.

Evaluating construction contractors in the pre-tendering stage through an integrated based model

There are different studies has introduced different methods and techniques to improve the performance and to reduce the delays in delivering construction projects. The selection of qualified contractors has a crucial importance which ensures delivering projects within the required time, quality, and cost. There are different national classification systems for contractors which are based on some similar and different criteria. This paper aims to develop a new model that helps in evaluating contractors in pre-tendering stage. The establishment of this model starts by listing 39 different criteria that are extracted from previous related studies. Then, 9 experts conducted a pairwise comparisons of those criteria using Analytical Hierarchy Process (AHP) which resulted in 10 important criteria that should be used in evaluating construction contractors in pre-tendering stage. Those 10 criteria were then evaluated by 21 specialized mangers in different contract departments to get the weight of each criterion using Multi Attribute Utility Theory (MAUT) which converts those different criteria that have different attributes dimensions to one unified measurement scale identified as the multi-attribute “utility”. At the end, the selection criteria are evaluated using numerical and nominal scale to calculate the final score using the weights of those criteria which will allocate the contractors that can go to the tendering stage. As this model introduces a method for evaluating contractors before tendering stage, it also allows the clients or owners redefine the selection criteria and to decide the minimum result to allow contractors to move to the tendering stage. So, this model will help decision makers to ensure that the contractor’s characteristics and capabilities meet the requirements of the allocated project. Effective and objective qualification processes will serve both parties, owners, and contractors, in delivering construction projects. The criteria of this model are established based on the requirements of the construction industry in Saudi Arabia.