Transactions Hong Kong Institution of Engineers最新文献_第3页

Impact of Micronutrient Technique (MNT) for biosolids reduction in wastewater treatment plants 微量营养素技术（MNT）对废水处理厂减少生物固体的影响

Transactions Hong Kong Institution of Engineers Pub Date : 2022-03-31 DOI: 10.33430/v29n1thie-2020-0041

Anthony See-Yuen To, A. Lau

引用次数: 0

Benchmarking site-plant resource matching performance of ready-mixed concrete delivery and placing 对预拌混凝土输送和浇筑的场厂资源匹配性能进行标杆

Transactions Hong Kong Institution of Engineers Pub Date : 2022-03-31 DOI: 10.33430/v29n1thie-2021-0021

Francis Siu, Anson Kwun Wang Wong, M. Anson

{"title":"Benchmarking site-plant resource matching performance of ready-mixed concrete delivery and placing","authors":"Francis Siu, Anson Kwun Wang Wong, M. Anson","doi":"10.33430/v29n1thie-2021-0021","DOIUrl":"https://doi.org/10.33430/v29n1thie-2021-0021","url":null,"abstract":"Since on-time concrete delivery is important to both contractors and suppliers, performance benchmarking of the concrete delivery process, as actually achieved in practice, is a worthwhile undertaking of potential benefit to the construction industry. However, there has been no thorough such benchmarking in Hong Kong for 20 years, since the study by Anson et al. (2002). This research study has provided an up-to-date benchmark of the site/supplier resource matching, or coordination, performance for big building superstructure pours, based on study of the records of 77 pours placed on five buildings under construction in Hong Kong. This research study also aimed to assess whether there was any evidence to suggest that site/ plant coordination performance has improved since 2000, not least due to the adoption of advanced technologies, which nowadays monitor the locations of truckmixers in real time throughout the day. Of great importance to the industry, however, and the most significant finding arising from this study, is that there is no support for the proposition that site/supplier resource coordination has improved over that 20-year interval. Truckmixer position tracking systems need to be capitalised upon with the introduction of data analysis simulation software and optimising scheduling applied in real time.","PeriodicalId":35587,"journal":{"name":"Transactions Hong Kong Institution of Engineers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44327942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Concrete placing crew and truckmixer productivities as affected by delivery scheduling policies 混凝土浇筑人员和卡车搅拌机的生产能力受到交货调度政策的影响

Transactions Hong Kong Institution of Engineers Pub Date : 2022-03-31 DOI: 10.33430/v29n1thie-2021-0018

M. Anson, Francis Siu

{"title":"Concrete placing crew and truckmixer productivities as affected by delivery scheduling policies","authors":"M. Anson, Francis Siu","doi":"10.33430/v29n1thie-2021-0018","DOIUrl":"https://doi.org/10.33430/v29n1thie-2021-0018","url":null,"abstract":"When ready mixed concrete is placed in forms on site, the goal is to ensure that both the placing crew is never idle when waiting for a delivery of concrete and that concrete delivery truckmixers never have to wait in a queue to be unloaded. This situation is almost never achieved in practice for a routine pour. Usually, both crews and truckmixers have to wait for some of the time. To better understand the behavioural characteristics of the concreting system, in terms of crew idle time and truckmixer excess time on site, simulation experiments were carried out to compare the effects of two truckmixer plant dispatch policies. For larger pours in particular, a serial dispatch policy is found more wasteful of truckmixer time than circulating dispatch as long as the correct size of circulating fleet is chosen. In addition, for serial dispatch, due to the system flow parameter variabilities seen in real life, it is suggested that to choose the theoretically optimum dispatch interval at the plant is wasteful of truckmixer time and that better coordinated plant and site resource matching requires slightly greater choice over the length of intervals.","PeriodicalId":35587,"journal":{"name":"Transactions Hong Kong Institution of Engineers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48045893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Visual-optical positioning and configuration of non-identified electronic pricing tags on retail shelves 零售货架上非识别电子价格标签的光学定位与配置

Transactions Hong Kong Institution of Engineers Pub Date : 2022-03-31 DOI: 10.33430/v29n1thie-2020-0002

Wai Tong Fung, Kin Man Lam

{"title":"Visual-optical positioning and configuration of non-identified electronic pricing tags on retail shelves","authors":"Wai Tong Fung, Kin Man Lam","doi":"10.33430/v29n1thie-2020-0002","DOIUrl":"https://doi.org/10.33430/v29n1thie-2020-0002","url":null,"abstract":"Firstly, a new positioning methodology for electronic pricing tags (EPTs) is proposed, performed by a Visual-Optical Mobile Module (VOMM) on the shelf. The module is composed of a monocular mobile camera and an infrared laser emitter built into a precise X-Y-Z angle divider driven by subdivision control of a stepping motor for Simultaneous Localization and Mapping (SLAM). The inter-tag distance between two EPTs can be down to a minimum of 2 mm. Secondly, the batteryoperated EPT consists of an infrared receiver and a low-cost MCU with LC-display. All EPTs can be positioned and automatically assigned to a specific ID. Hence, neither Radio Frequency Identification (RFID) nor a beacon is needed to tag the products. All the off-the-shelf products can be freely placed anywhere on the shelves. Thirdly, all individual EPTs can be auto-configured by a VOMM via Line-of-Sight (LoS) communication. The initial database simply records product identification and description, regular price, promotion price and sale period. Finally, the rotatable VOMM is installed on the ceiling, and a 3D floor plan can be generated to show the coordinates of products and EPTs. Shelves and zones can be generated automatically by using visual recognition and the information from the database according to the position of all EPTs on the shelves.","PeriodicalId":35587,"journal":{"name":"Transactions Hong Kong Institution of Engineers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45948597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A robust and efficient automated product recognition system based on scenario design methodology and computer vision techniques 基于场景设计方法和计算机视觉技术的鲁棒高效自动化产品识别系统

Transactions Hong Kong Institution of Engineers Pub Date : 2022-03-31 DOI: 10.33430/v29n1thie-2020-0003

Wai Tong Fung, Kin Man Lam

{"title":"A robust and efficient automated product recognition system based on scenario design methodology and computer vision techniques","authors":"Wai Tong Fung, Kin Man Lam","doi":"10.33430/v29n1thie-2020-0003","DOIUrl":"https://doi.org/10.33430/v29n1thie-2020-0003","url":null,"abstract":"Automated product recognition systems should minimise the online product verification time while keeping product recognition robust to human interventions, including misplaced products, rotated products and empty shelves. A predefined template of each product is generated offline, and scale and location invariant binary local features are employed for recognition. Three types of Sampling Bounding Mask (SBM) are defined and combined with RGB/LUV colour histograms, and matched with a planar level of a shelf by using the Earth Mover’s Distance, thereby reducing the computation time by 50%. Eight comprehensive product views are used to define five product scenarios on a shelf. The SBMs can be used to accurately distinguish the scenarios in a region at a level of shelf. By identifying four scenarios where a shopkeeper does not need to take any action to immediately reallocate misplaced products on shelves, the computation time is reduced by 80%. Six invariant keypoints and feature computation methods are compared for the recognition of product shelf items in different scenarios. The proposed approach speeds up the process by 200% to 300% for product matching. By integrating SBM view detection, the accuracy of product recognition in the front-view with rotations ranges from 90% to 95% using six different feature descriptors.","PeriodicalId":35587,"journal":{"name":"Transactions Hong Kong Institution of Engineers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44132723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improvement of cable defect identification for power distribution networks 配电网电缆缺陷识别的改进

Transactions Hong Kong Institution of Engineers Pub Date : 2022-03-31 DOI: 10.33430/v29n1thie-2021-0016

Ke Zhu, Ting Fat Ng

{"title":"Improvement of cable defect identification for power distribution networks","authors":"Ke Zhu, Ting Fat Ng","doi":"10.33430/v29n1thie-2021-0016","DOIUrl":"https://doi.org/10.33430/v29n1thie-2021-0016","url":null,"abstract":"Power distribution networks are critical infrastructures that secure delivery of electricity in a power system. Since electricity is mainly distributed through underground 11 kV and 22 kV power cables on Hong Kong Island, the maintenance of underground power cables is one of the most challenging jobs that The Hongkong Electric Co., Ltd. (HK Electric) has to face. This is because excavation for repair and replacement is difficult and time-consuming due to busy traffic and congested underground conditions. In order to improve maintenance efficacy, this study puts forward a new method to screen and locate potential defective component(s) of underground power cables by collectively using online and offline partial discharge (PD) diagnosing methods. The study also introduces new evaluation metrics (standard deviation of mean tan delta, and delta of mean tan delta) to identify cables at risk of developing water trees inside the cross-linked polyethylene (XLPE) insulation. The effectiveness of these two proposed methods has been validated on its distribution network. These improved identification methods for detecting cable defects could further enhance the reliability and security of HK Electric’s power distribution system.","PeriodicalId":35587,"journal":{"name":"Transactions Hong Kong Institution of Engineers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43873169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Special Issue with Awarded and Shortlisted Papers from the HKIE Outstanding Paper Award for Young Engineers/Researchers 2021 特刊刊载香港工程师学会杰出论文奖青年工程师/研究人员得奖及入围论文

Transactions Hong Kong Institution of Engineers Pub Date : 2021-12-31 DOI: 10.33430/v28n4

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Construction of the Tuen Mun–Chek Lap Kok Link Sub-sea Tunnels in Hong Kong 在香港兴建屯门至赤？角连接路海底隧道

Transactions Hong Kong Institution of Engineers Pub Date : 2021-09-30 DOI: 10.33430/v28n3thie-2019-0043

Albert Chan, Charles H C Yeung, A. Westmoreland, S. W. Fok, C. Ng, F. Guedon

{"title":"Construction of the Tuen Mun–Chek Lap Kok Link Sub-sea Tunnels in Hong Kong","authors":"Albert Chan, Charles H C Yeung, A. Westmoreland, S. W. Fok, C. Ng, F. Guedon","doi":"10.33430/v28n3thie-2019-0043","DOIUrl":"https://doi.org/10.33430/v28n3thie-2019-0043","url":null,"abstract":"The entire Tuen Mun–Chek Lap Kok Link (TM-CLKL) was commissioned on 27 December 2020 and comprises a 9 km dual twolane carriageway between Tuen Mun and North Lantau, Hong Kong. The challenges for the construction of the TM-CLKL tunnels included sub-sea tunnelling up to 55 m below sea level in mixed ground geology that required replacement of tunnel boring machine (TBM) cutting tools at hyperbaric pressure up to 5.8 bars; replacement of worn TBM cutting tools in complicated ground conditions; construction of approach tunnels in newly reclaimed land subject to long-term consolidation; and construction of cross passages at 100-metre intervals between the two sub-sea tunnels with a risk of sea water ingress at 5.5 bars. This project has deployed sophisticated techniques to surmount the challenges encountered during construction of the five-kilometre-long sub-sea tunnels. These included the use of the world’s largest slurry-type Mixshield TBM, 17.63 m in diameter, for the construction of the northern approach tunnel, followed by two 14 m diameter slurry-type Mixshield TBMs for the construction of the sub-sea tunnels; use of saturation diving techniques for TBM cutterhead interventions up to 5.8 bars which was the first such works in Hong Kong and one of only a few uses of saturation diving in tunnelling worldwide; use of ground freezing techniques in complicated ground conditions for TBM interventions to change worn cutting tools at the TBM cutterhead; TBM tunnelling in newly reclaimed land at the northern landfall and the southern landfall; and the construction of cross passages by mini-TBM using pipe jacking methods between the two main tunnel tubes which was the first such works ever undertaken anywhere in the world. This paper introduces the successful implementation of these techniques for the satisfactory completion of the TM-CLKL sub-sea tunnels.","PeriodicalId":35587,"journal":{"name":"Transactions Hong Kong Institution of Engineers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47928077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Construction dewatering in reclaimed land in Hong Kong — a review of best practices 香港填海土地的建筑脱水-最佳做法检讨

Transactions Hong Kong Institution of Engineers Pub Date : 2021-09-30 DOI: 10.33430/v28n3thie-2020-0038

R. Laver

引用次数: 0

Real-time object detection technology in railway operations 铁路运行中的实时目标检测技术

Transactions Hong Kong Institution of Engineers Pub Date : 2021-09-30 DOI: 10.33430/v28n3thie-2020-0028

Rock K C Ho, Zhangyu Wang, Simon Tang, Qiang Zhang

{"title":"Real-time object detection technology in railway operations","authors":"Rock K C Ho, Zhangyu Wang, Simon Tang, Qiang Zhang","doi":"10.33430/v28n3thie-2020-0028","DOIUrl":"https://doi.org/10.33430/v28n3thie-2020-0028","url":null,"abstract":"Development of new technology to enhance train operability, in particular during manual driving by real-time object detection on track, is one of the rising trends in the railway industry. The function of object detection can provide train operators with reminder alerts whenever there is an object detected close to a train, e.g. a defined distance from the train. In this paper, a two-stage vision-based method is proposed to achieve this goal. At first, the Targets Generation Stage focuses on extracting all potential targets by identifying the centre points of targets. Meanwhile, the Targets Reconfirmation Stage is further adopted to re-analyse the potential targets from the previous stage to filter out incorrect potential targets in the output. The experiment and evaluation result shows that the proposed method achieved an Average Precision (AP) of 0.876 and 0.526 respectively under typical scenario sub-groups and extreme scenario sub-groups of the data set collected from a real railway environment at the methodological level. Furthermore, at the application level, high performance with the False Alarm Rate (FAR) of 0.01% and Missed Detection Rate (MDR) of 0.94%, which is capable of practical application, was achieved during the operation in the Tsuen Wan Line (TWL) in Hong Kong.","PeriodicalId":35587,"journal":{"name":"Transactions Hong Kong Institution of Engineers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48696735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0