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Building Information Modelling for Building Services Engineering: Benefits, Barriers and Conducive Measures
No full textPurpose – Mandating the use of building information modelling (BIM) in building projects has sprawled, but the uptake of BIM in building services engineering (BSE) remains sluggish. The purpose of this paper is to explore how to achieve wider adoption of BIM in BSE. Design/methodology/approach – Through an extensive literature review, the benefits of, barriers to and measures conducive to, using BIM for BSE were identified and classified. Built upon the review and a focus group meeting, a questionnaire was devised for an industry-wide survey in Hong Kong and the survey data were processed by statistical analyses. Findings – On the ranking of the benefits, strong agreements existed between the BSE and non-BSE respondent groups; yet no significant agreement was found between the two groups on the rankings of the barriers or the conducive measures. The top conducive measure, according to the BSE group, is “Allow enough time in project programme for BIM model development”. Research limitations/implications – The data collection and analysis methods of this study may be used for similar BIM studies in other places. Practical implications – The priority of the conducive measures, which aid policy or decision makers in formulating how to get BIM effectively implemented in BSE, are useful information in the pursuit of a more productive and sustainable built environment. Originality/value – This BIM study is specifically on BSE rather than the other disciplines (e.g. architecture, structural engineering) that have been widely studied
Enhanced short-chain fatty acids production from waste-activated sludge by using peroxymonosulfate treatment combined with alkaline fermentation Corresponding
No full textExploring the Effects of Sustainability - Themed Branding Initiatives on Gen-Z Diners’ Willingness to Patronize
No full textSustainability is the capability to meet the needs of today without compromising the needs of future generations. Profit, planet and people are often mentioned as the 3 pillars of sustainability. The topic has been getting to higher and higher positions in the business priority list across various industry sectors these few years. And it comes with even more urgency for the F&B sector, which is often considered as one of the biggest waste culprits out there. On the other hand, many studies show that young generations are not only concerned but also willing to do something about sustainability e.g. UNiDAYS x Ad Age suggesting that 82% young diners prefer buying green products and Neilson noting that 77% of them are even willing to pay more to make it green. Encouragingly, some successful sustainability initiatives have been coming up over the years, from unsold food donation and “no-straw” initiatives across some big restaurant chains, to Banyan Tree’s highly successful “for good” business strategy, and even the fully committed B-Corp move of the ice cream brand Ben & Jerry etc.
However, sustainability has never been any easy topic for commercial sector because it takes some win-win balance between “for good” and “for profit” objectives to really make it “sustainable” at the end of the day. And that involves not only implementation complexity and profitability concerns, but also marketing expertise and lot of creativity etc. However, there is a huge dearth of research efforts regarding why young diners are so concerned about sustainability, what they are looking for behind those concerns, what and how to win their recognition as a sustainability-themed brand that they’d love to patronize repeatedly etc. Research efforts in these respects are of utmost importance for F&B companies to better tackle or leverage this challenge of sustainability for effective branding purpose. Academically, the study will shed light on the construct of sustainability as an affecting factor on willingness to patronize F&B brands.
This exploratory study will adopt convenience sampling leveraging easy access to students from 2 higher institutions in Hong Kong, who are very suitable target respondents representing local young diners. In-depth interviews with students will be adopted to facilitate open-end feedbacks from respondents following a pilot-tested interview protocol. Manual coding with triangulation process will be conducted to come up with findings afterwards. Key questions of the study are: (1) why young diners are concerned about sustainability strategy of F&B companies; (2) what and how to make young diners perceive (recognize) an F&B brand as one for sustainability so that they are willing to patronize repeatedly
Potential role of Candida albicans secreted aspartic protease 9 in serum induced-hyphal formation and interaction with oral epithelial cells
No full text© 2019 Elsevier Ltd Introduction: Candida albicans possesses the ability to switch rapidly between yeast to hyphal forms. Hyphal formation is a remarkable pathogenic characteristic, which allows C. albicans to invade into host cells. Objectives: This study was to investigate the role of the C. albicans SAP9 gene in hyphal formation and invasion ability. Methods: The morphology of fungal cells in the hyphal-inducing liquid media (YPD+10% fetal bovine serum) was observed by the microscopy. And the morphology of the colony on solid agar plates of YPD+10% fetal bovine serum was photographed by the digital camera. The mRNA expressions of hypha-associated genes in serum medium were also analyzed by real time PCR. Then for the interaction between C. albicans and oral epithelial cells, endocytosis essay, invasion essay and damage assay were performed to compare the differences between the sap9Δ/Δ mutant strain and wild type strain. Results: Compared with the wild type strain, the sap9Δ/Δ mutant strain exhibited a deficient yeast-to-hyphal morphological transition under serum hyphal-inducing conditions. Furthermore, the SAP9 knockout strain revealed a significant down-regulation of the expression of EFG1 (~40%), which is a transcription factor gene that mediates hyphae formation in C. albicans. Compared with the wild type strain, a 70% reduction in the endocytosis of the sap9Δ/Δ mutant strain by host cells was observed, as well as a 25% attenuation of active penetration and a 40% attenuation of host cell damage (P \u3c 0.05). Conclusions: Our data strongly suggests that C. albicans Sap9 is a potential hyphal-associated factor that responds to serum hyphal-inducing stimuli via a cAMP-protein kinase A pathway mediated by EFG1, and contributes to the process of invasion of Candida into the epithelial cells, leading to host cell damage
Large eddy simulation of vehicle emissions dispersion: Implications for on-road remote sensing measurements
No full text© 2020 Elsevier Ltd On-road remote sensing technology measures the concentration ratios of pollutants over CO2 in the exhaust plume in half a second when a vehicle passes by a measurement site, providing a rapid, non-intrusive and economic tool for vehicle emissions monitoring and control. A key assumption in such measurement is that the emission ratios are constant for a given plume. However, there is a lack of study on this assumption, whose validity could be affected by a number of factors, especially the engine operating conditions and turbulence. To guide the development of the next-generation remote sensing system, this study is conducted to investigate the effects of various factors on the emissions dispersion process in the vehicle near-wake region and their effects on remote sensing measurement. The emissions dispersion process is modelled using Large Eddy Simulation (LES). The studied factors include the height of the remote sensing beam, vehicle speed, acceleration and side wind. The results show that the measurable CO2 and NO exhaust plumes are relatively short at 30 km/h cruising speed, indicating that a large percentage of remote sensing readings within the measurement duration (0.5 s) are below the sensor detection limit which would distort the derived emission ratio. In addition, the valid measurement region of NO/CO2 emission ratio is even shorter than the measurable plume and is at the tailpipe height. The effect of vehicle speed (30–90 km/h) on the measurable plume length is insignificant. Under deceleration condition, the length of the valid NO/CO2 measurement region is shorter than under cruising and acceleration conditions. Side winds from the far-tailpipe direction have a significant effect on remote sensing measurements. The implications of these findings are discussed and possible solutions to improve the accuracy of remote sensing measurement are proposed
Spectrum-based pushover analysis for the quick seismic demand estimation of reinforced concrete shear walls
No full text© 2020 Institution of Structural Engineers In the design of medium- and high-rise buildings, the reinforced concrete (RC) shear wall structure is widely used to resist seismic loading. Thus, accurately predicting the seismic demand of this structural form becomes particularly important. However, existing multi-mode pushover analysis methods are mainly applied to predicting seismic demands of frame structures, while few attentions have been paid on other structural forms. In this paper, by revising the equation for predicting the overall roof displacement, the spectrum-based pushover analysis (SPA) of RC shear wall structures for the fast prediction of the seismic demand is presented. The accuracy of the SPA method in the fast prediction of seismic demands of RC shear wall structures was investigated through a case study on two representative RC shear wall buildings. The impact of the input ground motions (IGM) scaling target spectra on the accuracy of the SPA method was studied by selecting and scaling IGMs with the target spectra being the ASCE design spectra and conditional mean spectra. Seismic demands computed by the SPA method, the nonlinear response time history analysis (NLRHA), and the other two advanced methods of multi-mode pushover analysis were compared. It is indicated from the comparison of the seismic demands that the SPA method predicted seismic demands of RC shear wall structures with outstanding and consistent accuracy. Therefore, the SPA method can be considered as a solution for the fast seismic demand prediction of RC shear wall structures for different regions, where different target spectra are used as the seismic intensity representatives
Simulation of engine faults and their impact on emissions and vehicle performance for a liquefied petroleum gas taxi
No full text© 2020 Elsevier B.V. The deterioration of emissions control systems in a spark ignition engine is predominantly a gradual process of wear and tear occurring as vehicles accumulate mileage. As new innovations in engine and emissions technology have been progressively introduced to meet lower emissions targets, the impact of gradual deterioration of hardware has become more challenging to identify and quantify in the repair industry. When a pioneering emissions control programme utilising remote sensing to detect high emitting gasoline and liquefied petroleum gas (LPG) vehicles was to be introduced in Hong Kong, it became apparent the repair industry needed specialised training to assist with identifying the types of failures which would lead to high vehicle emissions. To identify the impact of hardware deterioration and failures, a Toyota Crown Comfort LPG taxi was used to demonstrate simulated failures of engine hardware systems to measure their impact on emissions, fuel consumption and drivability using a chassis dynamometer. This novel study simulated a broad range of deterioration and failures covering the intake, fuel supply, ignition, and exhaust systems. The results of the study showed significant THC and CO increases of up to 317% (0.604 g/km) and 782% (5.351 g/km) respectively for a simulated oxygen sensor high voltage fault and a sticky mixture control valve. The largest increase in NOx emissions was for restricted main fuel supply in the LPG vapouriser, producing an increase of 282% (1.41 g/km). Fuel consumption varied with increases of up to 15.5%. Drivability was impacted with poor idle from a number of faults and especially by a worn throttlebody which produced rough acceleration characteristics as well. This study clearly highlights the importance of having properly maintained emissions and engine hardware systems to achieve optimal fuel economy and compliant emissions levels, which could be reproduced in other regions for prescribed emissions regulation
A multi-timescale cold storage system within energy flexible buildings for power balance management of smart grids
No full text© 2020 Elsevier Ltd Energy storage is widely used in energy flexible buildings, which have great potential for relieving the power imbalance of electrical grids. However, most of the existing energy storage systems are designed for short-term storage, and only a few systems reported for long-term or multi-time scale storage. This paper introduces a new type of multi-timescale cold storage system consisted of a heat pipe-based natural ice storage subsystem and a dual-operation chiller for buildings to enhance their energy flexibility. The proposed system operated in different modes to provide the seasonal cold storage, nighttime chilled water storage, and urgent demand response services, which can be used for relieving the power imbalance in the timescale of the long-term, short-term and real-time respectively. The working principle, system configuration, operation modes, and the implementation of the proposed system for multi-timescale power management, are presented. A case study has been conducted in a building in Beijing to demonstrate the application and effectiveness. Results show that building load factors are greatly improved seasonally (from 19.5% to 49.5%) and daily (from 55.7% to 72.2%), and the power consumption is also considerably decreased (41.2%) during the demand response (DR) event
Practices of strength and conditioning coaches: A snapshot from different sports, countries and levels
Get PDFWeldon, A, Duncan, MJ, Turner, A, LaPlaca, D, Sampaio, J, and Christie, CJ. Practices of strength and conditioning coaches: a snapshot from different sports, countries, and expertise levels. J Strength Cond Res 36(5): 1335-1344, 2022-This study describes the practices of strength and conditioning coaches (SCCs) from different sports, countries, and expertise levels. One hundred fifty-six SCCs (31.9 ± 8.9 years old) completed an online survey, consisting of 40 questions (36 fixed response and 4 open-ended), with 8 sections as follows: (a) background information, (b) muscular strength and power development, (c) speed development, (d) plyometrics, (e) flexibility development, (f) physical testing, (g) technology use, and (h) programming and any additional comments. Responses were received from 48 sports and 17 countries. This study provides exploratory evidence incorporating responses primarily in soccer (45%), track and field (30%), volleyball (23%), golf (17%), and tennis (17%). A bachelor\u27s degree or higher were held by 99% of SCCs, of which 94% were in a sports science-related field, and 71% held a strength and conditioning related certification or accreditation. Periodization strategies and physical testing were used by 96% and 94% of SCCs respectively. The hang clean (82%), power clean (76%), and clean high pull (63%) were the most prescribed Olympic weightlifting exercises. Multiple hops/lunges (84%) were the most prescribed plyometrics exercises. For open-ended questions, 40% of SCCs wanted to integrate more technology into their programs and 30% believed technology will be the main future trend. Strength and conditioning coaches from different sports, countries, and expertise levels can use the information presented in this study to review their current practices and provide a source of new ideas for diversifying or modifying future practices
Exposure to phthalates impaired neurodevelopment through estrogenic effects and induced DNA damage in neurons
Get PDFPhthalates are commonly used in plastic products in daily life. The endocrine-disrupting effects of phthalates have been widely reported. Accumulating evidence from human cohorts and lab animals indicate exposure to phthalates might impair neurodevelopment. However, the direct causal relationship and mechanism between phthalates with neurodevelopment and neurotoxicity have not been firmly established. We found that phthalates (i.e. DBP, DINP, BBP) disrupted the expression of estrogen receptors (esr1, esr2a, esr2b), and impaired neurogenesis in the brain of zebrafish during embryonic development. Moreover, the abnormal expression of estrogen receptors, especially esr2a, was partly rescued in zebrafish which exposed to phthalates, with the estrogen receptor antagonist tamoxifen. Hence, impaired neurogenesis of zebrafish exposed to phthalates was partly reversed by tamoxifen treatment. Moreover, our results show that induced pluripotent stem cells (iPSC)-derived human neurons exposed to phthalates triggered double-strand DNA breaks in vitro. Overall, this study demonstrates that exposure to phthalates affects neurodevelopment in zebrafish embryos and induces neurotoxicity in human neurons partly through disrupting the expression of estrogen receptors