Ray Y. Zhong

The University of Hong Kong | HKU · Department of Industrial and Manufacturing Systems Engineering

Owing to the application of industrial wastes, geopolymers are generally regarded as a sustainable alternative to traditional construction materials. However, their lack of adoption on the industrial scale demands detailed investigations. This study conducts a comparative analysis of the compressive strength of different geopolymer and hybrid cemen...

The construction industry has been focused on sustainability, particularly with regards to reducing CO2 emissions and recycling construction and demolition (C&D) waste. This study focuses on the alternative technology adaptation of carbonized pavement compact production by using waste concrete powder (WCP) which can be a substitute material to conc...

The construction industry has a great impact on social and economic development because of its wide coverage and a large number of stakeholders involved. It is precisely owing to its large volume that technological innovation of the construction industry is relatively slow. The birth and rapid development of digital twins brings more hope to the co...

The concept of Digital Twin was invented not only for a static virtual mimic of reality, but also means an evolving digital copy which could stay consistent with its physical counterpart. The life-cycle management of a product or a system could not be completed without dynamic feature, while conventional methods to create graphic assets especially...

The National Natural Science Foundation of China (NSFC) and the Research Grants Council (RGC) of Hong Kong Joint Research Scheme (JRS) aims to promote collaboration between researchers / research teams in Hong Kong and the Mainland on the basis of complementing existing strengths of both sides. It also offers up to two conference grants to sponsor...

Digital twin is a comprehensive digital equivalent of an object or an activity, reflecting the semantic and geometric properties and behaviors through virtual models and data. Digital twin and related information technologies are widely used in the construction, operation and maintenance of infrastructure and facility. Transdisciplinary stakeholder...

Due to easy access, faster production, and on-demand printing, the applications of 3D printing are proliferating and reaching the mass customization level where individuals can print their self-design products. Many service providers emerge and supply 3D printers to allow mass customization within their specific service areas. Along with the techno...

Construction has been well-acknowledged as a growth driver of the economy. At the same time, nearly 40% of greenhouse gas emissions are referred to the building environment globally. The biggest challenge to the construction industry is obtaining sustainability with a balance of profit. It is widely acknowledged that intelligent construction is a p...

The proliferation of the e-commerce market has posed challenges to staff safety, product quality, and operational efficiency, especially for cold chain logistics (CCL). Recently, the logistics of vaccine supply under the worldwide COVID-19 pandemic rearouses public attention and calls for innovative solutions to tackle the challenges remaining in C...

Prefabricated production Planning, Scheduling, and Execution (PSE) is crucial for the on-time delivery of prefabricated modules in Modular Prefabricated Construction (MPC). In prefabricated production, various uncertainties decrease the effectiveness of production PSE, increasing construction periods and costs. However, a stable and resilient fixed...

Facilitated by the improved prefabrication rate and polymerization degree using Modular Integrated Construction (MiC), fit-out operations are converged with the off-site production and on-site assembly of prefabricated modules. Information technologies are used for MiC fit-out management and heterogeneous digital twins are generated. However, flexi...

This paper introduces a data-driven ESG assessment approach using blockchain technology and stochastic multicriteria acceptability analysis (SMAA-2) to address the data opaqueness and assessment subjectivity problems. On the one hand, blockchain provides a transparent and trackable ledger to store and share ESG data among the listed companies, inve...

Background : The traditional healthcare process centers on the hospital rather than the individual patient. The demand for continuous monitoring is increasing with the increasing proportion of patients with chronic diseases and the elderly. Wearable medical devices have brought medical monitoring into the Internet age. To improve the devices' adapt...

Recently 3D printing of geopolymers gained increasing attention due to their dual-dimensional sustainability from technology and materials perspectives. The current research first defines the criteria for the assessment of the sustainability of 3D printed geopolymers. Four different aspects including productivity assessment, economic influence, env...

Distributed additive manufacturing (AM) has emerged as an innovative service-oriented paradigm for decentralized production of personalized products. In this paper, a resource sharing problem for product service system (PSS)- and cloud-enabled additive manufacturing platforms is addressed. A PSS-enabled business model is proposed to share resources...

There is a recognized need for mass personalization for sustainability at scale. Mass personalization is becoming a leading research trend in the latest Industrial Revolution, whereas substantial research has been undertaken on the role of Industry 4.0 enabling technologies. The world is moving beyond mass customization, while manufacturing has led...

Under the support of advanced information technologies, smart mine is proposed to meet the demands of green, safe, and automated coal mining. Due to the potential advantages in promoting the automation of coal mining, smart mine has attracted wide attention from industry and academia. Current studies related to the smart mine mainly focus on the ma...

About the talk A rapidly aging population is one of the major challenges facing the society. It is estimated that by 2050, the global population of people aged 65 or older will reach 1.6 billion. This is a major difficulty that many elders are experiencing severe limitations in mobility and manipulability in their daily lives, resulting in tremendo...

The construction industry has a great impact on social and economic development because of its wide coverage and a large number of stakeholders involved. It is precisely owing to its large volume that technological innovation of the construction industry is relatively slow. The birth and rapid development of digital twins brings more hope to the co...

Under the support of advanced information technologies, smart mine is proposed to meet the demands of green, safe, and automated coal mining. Due to the potential advantages in promoting the automation of coal mining, smart mine has attracted wide attention from industry and academia. Current studies related to the smart mine mainly focus on the ma...

The study explored a deep learning image super-resolution approach which is commonly used in face recognition, video perception and other fields. These generative adversarial networks usually have high-frequency texture details. The relevant textures of high-resolution images could be transferred as reference images to low-resolution images. The la...

Domestic trash detection is an essential technology toward achieving a smart city. Due to the complexity and variability of urban trash scenarios, the existing trash detection algorithms suffer from low detection rates and high false positives, as well as the general problem of slow speed in industrial applications. This paper proposes an i-YOLOX m...

Package design for mass order is becoming one of the significant issues to influent package quality in fresh e-commerce logistics. However, the package schemes of fresh products remain challenging, due to various fresh products storage and delivery requirements, and complex environment temperature in a long express distance. This paper proposes a p...

A multi‐agent iterative optimisation method based on deep reinforcement learning is proposed for the balancing and sequencing problem in mixed model assembly lines. Based on the Markov decision process model for balancing and sequencing, a balancing agent using a deep deterministic policy gradient algorithm, a sequencing agent using an Actor–Critic...

Predictive maintenance (PdM) is a prominent anomaly prediction strategy in the manufacturing system given the increasing need to minimize downtime and economic losses. It is available for PdM to monitor industrial equipment continuously with smart electrical sensors and predict the health condition with machine learning algorithms. However, the per...

Date and time: July 20 (Wed), 2022, 20:00 HKT (GMT+8) [Local time] Zoom link: https://hku.zoom.us/j/93965533071 Zoom meeting ID: 939 6553 3071 Seminar Title: Is digital manufacturing smart? Abstract: For more than a decade, the wide implementation of sensors and connected devices has been heralded as the next industrial revolution. In this t...

We are pleased to present this Special Issue of TASE, including 12 extended articles selected from the technical program of the 2020 International Conference on Automation Science and Engineering (CASE2020). CASE2020 was held virtually due to the COVID19 pandemics, August 20–21, 2020, and was originally scheduled in Hong Kong, China. CASE is an off...

Machine status detection is very critical to ensure the smoothness of processing workpieces in terms of efficiency and quality. In light of the significance of acoustic emission (AE) signals for the monitoring of wire electrical discharge machining (WEDM) processes and the strong feature extraction ability of deep learning, this paper proposes a ph...

Planning, scheduling, and execution (PSE) are essential for coordinating tasks during on-site assembly in prefabricated construction. Real-time synchronization supports collaborative decision making for planning and scheduling, and dynamic adjustment of execution in on-site assembly. However, simple and resilient mechanisms are lacking for on-site...

Cyber-Physical System (CPS) is one of the most promising directions of Industry 4.0 smart manufacturing. Abundant manufacturing data and information are available for decision-makers in real-time thanks to the application of various frontier technologies in CPS. However, the inherent complexity and uncertainty of manufacturing optimization still pl...

Date and time: June 1 (Wed), 2022, 20:00 HKT (GMT+8) [Local time] Zoom link: https://hku.zoom.us/j/93965533071 Zoom meeting ID: 939 6553 3071 Seminar Title: An Authentication Platform based on the Patented 3D Printing Digital Watermarking Technology and Blockchain Technology Abstract: This presentation outlines a project that aims to provide...

Seminar Title: Data-Driven Creation and Operation of Digital Twins for Discrete Event Systems Date and time: May 4 (Wed), 2022, 20:00 HKT (GMT+8) Zoom link: https://hku.zoom.us/j/93965533071 Zoom meeting ID: 939 6553 3071 Abstract: With the coming of the Industry 4.0 wave, digital representations of manufacturing systems have been promoted fr...

Modular Integrated Construction (MiC) is a game-changing approach with enhanced quality, productivity, and sustainability, which transforms cast-in-situ into on-site assembly of prefabricated modules. On-site assembly is an uncertain and complex stage in MiC scenario, due to high variability of outside conditions, organization of multi-contractors,...

Hong Kong’s construction industry, known for its massive building infrastructure, produces an enormous amount of waste every year, the vast majority of which is disposed for landfills. Therefore, some effective operational measures and waste management policies have been implemented. However, enormous waste remains a concern for stakeholders and ex...

The efficiency of the factory logistics after production and before warehousing becomes no less important in terms of the overall productivity, product quality, and service level, especially under mass customization. However, it almost remains traditional in the industry and gains insufficient academic studies due to its triviality and irregularity...

Purpose Blockchain as a disruptive technology has revolutionized many industries, such as finance, logistics and manufacturing sectors. This paper aims to explore Blockchain applications in construction to effectively manage project workflows and uplift construction efficiency. Design/methodology/approach Semi-structured in-depth interviews were c...

The layout of fixed-position assembly islands (FPAI) offers flexibility and efficiency for the production of bulky or fragile products with medium variety and volumes. With the unique production operations and customized delivery requirements in FPAI, the manufacturing practitioners are plagued by long waiting times, frequent setups, and high finis...

The latest trends of sustainability have introduced environmentally friendly materials and green technologies in the construction sector. However, these materials and technologies are not fully adopted due to certain limitations in their practical applications. In this concern, extensive research has been conducted on the geopolymer materials and a...

With the rapid improvement of Industrial Internet of Things and artificial intelligence, predictive maintenance (PdM) has attracted great attention from both academia and industrial practitioners. When equipment running, electrical attributes have intrinsic relations. Meanwhile, they are changing over time. Existing PdM models are often limited by...

In the in-situ quality detection of yarn production, image deblurring plays a critical role in the vision-based detection systems to restore a sharp image and provide more accurate input for inspection. However, image deblurring is still challenging since the current methods are mainly based on the pre-defined blur degree. In dynamic yarn productio...

Smart manufacturing is undergoing rapid development along with many disruptive technologies, such as Internet of Things, cyber-physical system and cloud computing. A myriad of heterogeneous manufacturing services can be dynamically perceived, connected and interoperated to satisfy various customized demands. In smart manufacturing, the market equil...

Modern manufacturing systems are complicated orchestrations of many resources, enablers, and technologies that come together to fulfill the strategic vision of an enterprise. Organization of all of the elements in-volved in such a system is a complex optimization endeavor that requires amalgamation of many data sources and patterns of knowledge, as...

Detection algorithms play an important role in the life-cycle management of smart vision-based defect detection equipment. This paper proposes a brain-inspired interpretable network pruning method for smart detection equipment for online defect detection scenarios. A brain-inspired neuronal circuit decomposition model is constructed from the view o...

Modular Integrated Construction (MiC) has been one of the most innovative solutions to address the ever-growing housing demands in megacities such as Hong Kong. MiC offers a range of benefits including cost-effectiveness, high productivity, and high sustainability for construction industry. Multiple stakeholders in MiC project, such as project clie...

Internet of things (IoT) and Radio Frequency Identification (RFID) technologies are gradually adopted in manufacturing recently. With the aid of them, numerous data is generated from daily manufacturing operations. Big data analytics is used in locating deficiencies and thus improving the productivity of a manufacturing shopfloor. Many studies have...

The manufacturing industry is experiencing a service-oriented transformation in the digitalisation era. However, many small and middle enterprises (SMEs) still rely on traditional manufacturing patterns in which they can hardly servitise manufacturing resources due to the limited budget and poor digitalisation capability. To servitise manufacturing...

Diversified customer needs make the production system more susceptible to high-frequency fluctuations of uncertain factors (UFs), which puts forward higher requirements for the real-time and systematic decision-making of the system. The opti-state control strategy enables the system to maintain the adaptive optimal state after being disturbed. The...

The rapid advances of information technology have pushed society into the fourth industrial revolution (I4.0). It requires an integration of value chain organization and management across the product lifecycle driven by the Internet industrialization, industrial digitalization and intellectualization, and industrial integration. PLM is the business...

The Fourth Industrial Revolution (Industry 4.0) leads to mass personalisation as an emerging manufacturing paradigm. Mass personalisation focuses on uniquely made products to individuals at scale. Global challenges encourage mass personalisation manufacturing with efficiency competitive to mass production. Driven by individualisation as a trend and...

Logistics interfaces with manufacturing throughout the entire production process need synchronous operations. For achieving integrated organization and operations between manufacturing and logistics, this article introduces the concept of shop-floor logistics and manufacturing synchronization with four principles, including: 1) synchronization-orie...

Purpose This paper proposes an evaluation model for prefabricated construction to guide a supply chain with controllable costs. Prefabricated construction is prevalent due to area limitations. Nevertheless, the development is limited by budget control and identifying the factors affecting cost. The degree of close collaboration in the supply chain...

Peculiar characteristics of squeeze casted hybrid aluminum matrix composites (AMCs) enable it as an appropriate candidate for various manufacturing applications but also make their machining challenging. For that reason, wire electric discharge machining (WEDM) has been preferred over conventional machining processes for the cutting squeeze casted...

As an underlying and backbone technology of Bitcoin, Blockchain attracted extensive attention worldwide in recent years due to its unique characteristics of decentralization, openness, immutability, anonymity, etc., which enables it to build a trust basis through recording the point-to-point decentralized transactions in an immutable way via the at...

Date and time: July 28 (Wed), 2021, 20:00 HKT (GMT+8) [Local time] Zoom link: https://hku.zoom.us/j/93965533071 Zoom meeting ID: 939 6553 3071 Seminar Title: Additive Manufacturing of Large Components Abstract: Additive Manufacturing (AM) or 3D printing as recognised by the public, has grown substantially over the last 25 years into a predic...

Wire electrical discharge machining (WEDM), widely used to fabricate micro and precision parts in manufacturing industry, is a nontraditional machining method using discharge energy which is transformed into thermal energy to efficiently remove materials. A great amount of research has been conducted based on pulse characteristics. However, the spa...

In this paper, the problem of hybrid flow shop scheduling with common due dates (HFSCDD) is studied, and the objectives are to minimize the total waiting time and the total earliness/tardiness issues that arise. This study was motivated by a real-life shop floor, with the predefined goal of meeting the requirements of the final product in many manu...

Companies with manufacturing systems that are more responsive and resilient will be able to survive or even gain market shares in the face of the unpredicted variable of an outbreak similar to the COVID-19 pandemic. Motivated by an industrial company restructuring its manufacturing system with the layout of fixed-position assembly islands (FPAI) du...

With the development of Internet of Things (IoT), 5 G, and cloud computing technologies, the amount of data from manufacturing systems has been increasing rapidly. With massive industrial data, achievements beyond expectations have been made in the product design, manufacturing, and maintain process. Big data analytics (BDA) have been a core techno...

Industry 4.0 connotes a new industrial revolution with the convergence between physical and digital spaces, which is revolutionizing the way that production operations are managed. The requirement of increased productivity, improved flexibility and resilience, and reduced cost in Industry 4.0 manufacturing calls for new paradigms that comply with t...

With the growing complexity of manufacturing systems nowadays, the effective assessment of important risk factors inherent in the manufacturing process is crucial for the stability and reliability of such complex systems. Thus, this article proposes a data-driven approach using the state-of-art machine learning techniques to assess and forecast the...

Source separation is regarded as a best practice for sustainable waste management, which is essential for a transition to a circular economy to recover value from waste. However, its implementation in China has faced many difficulties which are primarily inherent in the public’s behaviour towards source separation of household waste. Based on multi...

Sanitary and stormwater sewers are buried assets that play important roles in the prevention of diseases and the reduction of health risks for our societies. Due to their hidden nature, these assets are not frequently assessed and maintained to optimal conditions. The lack of maintenance can cause sewer blockages and overflows that result in the re...

This research is motivated by a real-life case which runs the public transportation services in Hong Kong, China. The mass transit railway (MTR) is contemplating the maintenance by considering the manpower planning in its depot. The main purpose of this research is to improve the efficiency of assembly with adjustable manpower planning based on an...

With the advantages of long-distance contactless identification and data storage capacity, the use of radio frequency identification (RFID) technology in the fields of manufacturing, transportation and logistics has been widely reported. Fatigue of workers plays a critical role in impacting the manufacturing efficiency because it reduces productivi...

In the era of digitalization, there are many emerging technologies, such as the Internet of Things (IoT), Digital Twin (DT), Cloud Computing and Artificial Intelligence (AI), which are quickly developped and used in product design and development. Among those technologies, DT is one promising technology which has been widely used in different indus...

A recent global outbreak of Corona Virus Disease 2019 (COVID-19) has led to massive supply chain disruption, resulting in difficulties for manufacturers on recovering their supply chains in a short term. This paper presents a supply chain disruption recovery strategy with the motivation of changing the original product type to cope with that. In or...