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The study aims to reveal the state of building operation and maintenance (O&M) manpower in Hong Kong. In addition, the study included supply and demand of O&M practitioners, gaps between their required and possessed competences and ways to meet the manpower needs.

After developing a model that integrates manpower levels (L), trades (T) and natures (N) of O&M works (named as “LTN” model), a full spectrum of O&M jobs were established followed by collecting data of 75 organizations and 402 stakeholders through two surveys.

Besides the large O&M workforce, vacancy rates of the jobs were found to be significant. For the different trades and natures of O&M works, the knowledge/skills levels perceived by the stakeholders were lower than the corresponding importance levels.

The methodology of the study can be used in future research for revealing the state of O&M manpower in Hong Kong and cities alike. The way in which the “LTN” model was developed may be used as a reference for constructing similar models for manpower research in other industries.

The findings and the measures for improving the O&M manpower can assist policymakers and human resources departments to formulate necessary education and training courses for the building industry.

The study is the first of its kind focusing on building O&M manpower. The state of the manpower it unveiled forms a basis for comparison with similar findings in future.

Tourism is a pillar of the service industries in Hong Kong. Its growth entails quality hotel accommodations where cost‐effective operation and maintenance (O&M) of their facilities are essential. A benchmarking study was carried out on ten luxury hotels with the aim of identifying the significance and performance of various O&M cost elements.

A benchmarking club was set up for the practitioners participating in the study. A template was piloted and then refined for use in collecting data, which include the hotels' characteristics, their expenditures on maintenance and project works, in‐house manpower and payroll, contract maintenance costs, and utilities costs and consumptions.

Energy cost dominates the O&M expenditure of hotels. The cost for maintaining lifts and escalators constitutes a major part of contract maintenance costs. Larger hotels can enjoy a lower unit O&M cost.

Quality, age and occupancy rate of hotels are factors which warrant further work to investigate their effects on O&M costs. It is also necessary to study what cost‐sensitive parameters are appropriate for use in normalising the costs of different trades of O&M work.

It has been shown how a benchmarking curve can be constructed for identifying the performance of utilities cost. This approach can be taken to develop similar curves for benchmarking other cost elements, as well as other aspects including processes and values of O&M works.

Sensitive O&M cost data are seldom disclosed. The study has overcome the difficulties with their collection and the cost benchmarks presented are useful references for hotel practitioners.

The recession in the late 1990s in Hong Kong has triggered many commercial building owners to cut operation and maintenance (O&M) cost via outsourcing. The purpose of this paper is to investigate the dominant expenditure on O&M service and examine the relation between extent of outsourcing and rental income of the buildings.

Experienced O&M practitioners were interviewed to collect both quantitative and qualitative data of the commercial buildings they looked after. The in‐house and outsourced O&M costs, air‐conditioning energy costs, rental incomes, and management and air‐conditioning fees for the buildings were analysed.

The total air‐conditioning O&M cost is the principal cost item, with the energy cost being the dominant element. The analysis reveals that the extent of outsourcing bore little correlation with the air‐conditioning O&M cost and the rental income.

Further work may take a similar approach to identify the extent and effect of outsourcing other kinds of services that underpin the core business of an organisation.

Varying the extent of outsourcing O&M service was found to be unpromising for enhancing rental performance or cutting O&M expenditure. This is an important point that the building managers should address when considering whether to go for outsourcing.

The findings imply that in the building O&M service industry, it would be more economical to outsource or undertake in‐house the vast majority of O&M work. The focus for cost minimization should be to improve building energy performance rather than reducing labour resources through outsourcing.

This paper aims to discuss the limitations surrounding the yoghurt industry and challenges to producing a bio-yoghurt tablet. The paper looks into challenge facing the yoghurt industry, such as manufacturing and distribution, its short shelf life, heat-sensitivity and relatively heavy weight. It further looks into the selection of strains, excipients and storage conditions with special consideration towards maintaining the viability of the probiotics inside bio-yoghurt tablets. The paper also discusses yoghurt standards and definitions across various countries and suggests a more uniform standard be embraced across countries for ease of categorization and production.

The paper is divided into a few major sections; each exploring various aspects of the yoghurt industry. Topics discussed include challenges in yoghurt production and storage; processes involved in bio-yoghurt tablet production, e.g. maximising viability, choice of excipients and more; market trends of yoghurt consumption and potential; and various food standards in countries around the world with a focus on yoghurt.

The review finds that yoghurt is a segment of the food industry with big growth potential. Most of the problems associated with yoghurt, i.e. poor shelf life, and heavy weight, can be circumvented by transforming it into a bio-yoghurt tablet. The paper further identifies food standard variations among different countries around the world which could impede yoghurt manufacture and acceptance.

This paper looks the various challenges surrounding the increased uptake of yoghurt, specifically in the Asian markets and suggests a viable option to overcome this problem, i.e. the use of a bio-yoghurt tablet. Should the worldwide bodies come together and agree to a universal standard involving yoghurt, the industry may see an even bigger expansion.

The main purpose of this paper is to find a simple method to improve the breakdown voltage of BJTs fabricated on SOI.

We have used two‐dimensional device simulation to examine the effect of a collector tub on the collector breakdown of the SOI based BJTs. This method involves creating a collector tub by etching the buried oxide followed by an n‐type implantation on the collector n/n+ junction side.

First, our method reduces the peak electric field at the silicon film‐BOX interface and secondly, the collector‐tub facilitates the collector potential to be absorbed by both collector drift and substrate regions improving the collector breakdown significantly.

An improved breakdown voltage improves the reliability of BJTs on SOI.

Our results show that the BV_CEO of the bipolar transistors with a collector‐tub is enhanced by 2.7 times when compared with a conventional lateral bipolar transistor (LBT) with identical drift region doping. This improvement has an important practical value in the fabrication of SOI‐based LBTs.

This paper aims to first apply more advanced anisotropic yield criterions as Yld91 and Yld2004 to spherical indentation simulations, and investigate plastic anisotropy identified from indentation simulations following different yield criterions (Hill48, Yld91, Yld2004) to discover laws. It also aims to compare the difference in plastic anisotropy identified from indentation on three yield criterions and evaluate the applicability of plastic anisotropy.

This paper uses indentation simulations on different yield criterions to identify plastic anisotropy. First, the trust-region techniques based on the nonlinear least-squares method are used to determine anisotropy coefficients of Yld91 and Yld2004. Then, Yld91 and Yld2004 are implemented into ABAQUS software using user-defined material (UMAT) subroutines with the proposed universal structure. Finally, through considering comprehensively the key factors, the locations of the optimal data acquisition points in indentation simulations on different yield criterions are determined. And, the identified stress–strain curves are compared with experimental data.

This paper discovers that indentation on Yld2004 is able to fully identify difference in equivalent plastic strain between 0° and 90° directions when indentation depth h_t is relatively smaller. And, this research demonstrates conclusively that plastic anisotropy identified from indentation on Yld2004 and Yld91 is more applicable at larger strains than that on Hill48, and that on Yld2004 is more applicable than that on Yld91, overall. In addition, the method on the determination of the locations of the optimal data acquisition points is demonstrated to be also valid for anisotropic material.

This paper first investigates plastic anisotropic properties and laws identified from indentation simulations following more advanced anisotropic yield criterions and provides reference for later research.

This study aims to investigate the production and abrasive wear rate of functionally graded TiB₂/Al composites. TiB₂ particles have been spontaneously formed in liquid matrix using in situ technique. The properties of composites such as hardness, abrasive wear rate and microstructure have been examined.

In situ TiB₂ reinforcement phase was synthesized by using a liquid Al–Ti–B system. A semi-solid composite (Al_(l)-TiB_2(s)) prepared at 900°C was solidified under a centrifugal force to both grade functionally and give the final shape to materials. Abrasive wear test of materials was conducted using the pin-on-disk method at room temperature. The wear tests were carried out with two different loads of 1 Newton (N) and 2 N, a sliding velocity of 3.5 m s⁻¹ and a sliding distance of 75 m.

This research provided the following findings; TiB₂ particles can be successfully synthesized with in situ reaction technique in molten aluminum. It was determined that abrasive wear rate increases with increasing load and decreases with increasing TiB₂ reinforcement content within matrix.

In previous studies, there have been many trials on the in situ production of TiB₂-reinforced aluminum matrix composites. However, there are few studies on production of in situ TiB₂-reinforced aluminum matrix functionally graded materials. At the same time, there is no study that the properties of composite, such as hardness and abrasive wear rate, are examined together according to centrifugal force.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2019-0538/

The purpose of this paper is to focus on natural food additives identified in the drumstick (Moringa Oleifera) and their probable application as novel ingredients in the development of functional food products. This plant additive has attracted interest as one of the prominent candidates for the purpose of improving processing, quality and the safety of various livestock foods such as meat, milk, fish and their products. The search of natural food additives for the processing and preservation of high-quality, ready-to-eat products has notably increased due to the adverse effects of chemical additives on human health.

Traditionally, Moringa is a pan-tropical plant species, which is well-known for its nutritional and medicinal properties in human nutrition. Its leaves, seeds, flowers, pods (fruit), bark and roots are extremely valuable sources of nutrition for people of all ages. Moringa is nowadays also considered as an important source of nutraceuticals which may find wide application in the food industry. These nutraceuticals have a positive impact on the body’s function or condition by affecting the digestive, endocrine, cardiovascular, immune and nervous systems, and it may ultimately influence health.

Several additives that are released in vitro or in vivo from various parts of Moringa have been attributed to different health effects, including antimicrobial properties, antioxidant activities, anti-tumour, anti-inflammatory, anti-ulcer, anti-atherosclerotic, anti-convulsant activities and there is enhancement of nutritional and organoleptic attributes of various livestock foods. Extensive research has been undertaken to identify and characterize these additives as a new source of biologically active ingredients for the development of functional foods with specific benefits for human health.

This paper focuses on the properties, utilization and scope of Moringa Oleifera in livestock products, all of which indicate that its effective utilization is the need of the hour.

The purpose of this paper is to understand the effect of graphite content on the properties of aluminum alloy/silicon carbide/granite (Al/SiC/Gr) composites.

Hardness and wear tests were applied to the powder metallurgical composites, and microstructural characterization was conducted.

Optimum graphite content for maximum wear resistance is reported as weight 6 per cent.

Results of this study may help light weight Al/SiC/Gr composites to be used in different industrial applications.

It has been observed from the history of failed dies used in local extrusion industry that after certain press cycles, severe die damage occurs by using more number of in‐house recycled billets. The purpose of this paper is to focus on the effect of billet quality on the extrusion die service life, based on using microstructural and finite element analyses.

Numerical solution of stress distribution in extrusion die using microstructural and finite element analyses.

Simulation results demonstrate that extrusion die experiences high stresses and strains at critical locations by running secondary billets. Billet deformation behavior also shows that secondary billet has more resistance to flow during extrusion cycle, which results in such high stresses and strains in the die.

The study includes a particular die used to extrude the aluminum alloy billets. It may need to generalized including materials other than aluminum alloy.

The findings are original and believed to be useful for engineers working in the extrusion dies. Since it is shown that secondary billets (recycled billets) have more resistance to flow in the dye, a care should be taken when estimating the die life for the practical applications.

It is an original work. It deals with the comparison of new and recycled billets's performance in terms of stress formation in the die during the extrusion cycle.