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For an unbalanced cooperative game, its grand coalition can be stabilized by some instruments, such as subsidization and penalization, that impose new cost terms to certain coalitions. In this paper, we study an alternative instrument, referred to as cost adjustment, that does not need to impose any new coalition-specific cost terms. Specifically, our approach is to adjust existing cost coefficients of the game under which (i) the game becomes balanced so that the grand coalition becomes stable, (ii) a desired way of cooperation is optimal for the grand coalition to adopt, and (iii) the total cost to be shared by the grand coalition is within a prescribed range. Focusing on a broad class of cooperative games, known as integer minimization games, we formulate the problem on how to optimize the cost adjustment as a constrained inverse optimization problem. We prove NP -hardness and derive easy-to-check feasibility conditions for the problem. Based on two linear programming reformulations, we develop two solution algorithms. One is a cutting-plane algorithm, which runs in polynomial time when the corresponding separation problem is polynomial time solvable. The other needs to explicitly derive all the inequalities of a linear program, which runs in polynomial time when the linear program contains only a polynomial number of inequalities. We apply our models and solution algorithms to two typical unbalanced games, including a weighted matching game and an uncapacitated facility location game, showing that their optimal cost adjustments can be obtained in polynomial time. History: Accepted by Area Editor Andrea Lodi for Design & Analysis of Algorithms—Discrete. Funding: This work was supported by the National Natural Science Foundation of China [Grants 72022018 and 72091210]; the Research Grants Council of the Hong Kong SAR, China [Grant 16210020]; Hong Kong Polytechnic University [Grant P0032007]; and the Youth Innovation Promotion Association, Chinese Academy of Sciences [Grant 2021454]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/ijoc.2022.0268. [ABSTRACT FROM AUTHOR]

This paper develops a cost-effective sequential route recommender system to provide real-time routing recommendations for vacant taxis searching for the next passenger. We propose a prediction-and-optimization framework to recommend the searching route that maximizes the expected profit of the next successful passenger pickup based on the dynamic taxi demand-supply distribution. Specifically, this system features a deep learning-based predictor that dynamically predicts the passenger pickup probability on a road segment and a recursive searching algorithm that recommends the optimal searching route. The predictor integrates a graph convolution network (GCN) to capture the spatial distribution and a long short-term memory (LSTM) to capture the temporal dynamics of taxi demand and supply. The GCN-LSTM model can accurately predict the pickup probability on a road segment with the consideration of potential taxi oversupply. Then, the dynamic distribution of pickup probability is fed into the route optimization algorithm to recommend the optimal searching routes sequentially as route inquiries emerge in the system. The recursion tree-based route optimization algorithm can significantly reduce the computational time and provide the optimal routes within seconds for real-time implementation. Finally, extensive experiments using Beijing Taxi GPS data demonstrate the effectiveness and efficiency of the proposed recommender system. History: Accepted by Ram Ramesh, Area Editor for Data Science and Machine Learning. Funding: This work was partially supported by the Hong Kong Research Grants Council [Grants CityU 21500220, CityU 11504322] and the National Natural Science Foundation of China [Grant 72201222]. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information (https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2021.0112) as well as from the IJOC GitHub software repository (https://github.com/INFORMSJoC/2021.0112). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/. [ABSTRACT FROM AUTHOR]

Many warehouses involved in e-commerce order fulfillment use robotic mobile fulfillment systems. Because demand and variability can be high, scheduling orders, robots, and storage pods in interaction with manual workstations are critical to obtaining high performance. Simultaneously, the scheduling problem is extremely complicated because of interactions between decisions, many of which must be taken timely because of short planning horizons and a constantly changing environment. This paper models all such scheduling decisions in combination to minimize order fulfillment time. We propose two decision methods for the above scheduling problem. The models batch the orders using different batching methods and assign orders and batches to pods and workstations in sequence and robots to jobs. Order picking and stock replenishment operations are included in the models. We conduct numerical experiments based on a real-world case to validate the efficacy and efficiency of the model and algorithm. Instances with 14 workstations, 400 orders, 300 stock-keeping units (SKUs), 160 pods, and 160 robots can be solved to near optimality within four minutes. Our methods can be applied to large instances, for example, using a rolling horizon. Because our model can be solved relatively fast, it can be used to take managerial decisions and obtain executive insights. Our results show that making integrated decisions, even when done heuristically, is more beneficial than sequential, isolated optimization. We also find that positioning pick stations close together along one of the system's long sides is efficient. The replenishment stations can be grouped along another side. Another finding is that SKU diversity per pod and SKU dispersion over pods have strong and positive impacts on the total completion time of handling order batches. Funding: This work was supported by National Natural Science Foundation of China [72025103, 72361137001, 71831008, 72071173] and the Research Grants Council of the Hong Kong Special Administrative Region, China [HKSAR RGC TRS T32-707/22-N]. Supplemental Material: The e-companion is available at https://doi.org/10.1287/trsc.2022.0265. [ABSTRACT FROM AUTHOR]

The ℓ 0 trend filtering ( ℓ 0 -TF) is a new effective tool for nonparametric regression with the power of automatic knot detection in function values or derivatives. It overcomes the drawback of ℓ 1 -TF that is known to have bias issues. To solve the ℓ 0 -TF problem, we propose an alternating minimization induced active set (AMIAS) search method based on the necessary optimality conditions derived from an augmented Lagrangian framework. The proposed method takes full advantage of the primal and dual variables with complementary supports, and decouples the high-dimensional problem into two subsystems on the active and inactive sets, respectively. A sequential AMIAS algorithm with warm start initialization is developed for efficient determination of the cardinality parameter, along with the output of solution paths. Theoretically, the oracle estimator of ℓ 0 -TF is justified to behave like regression splines under the continuous time setting with mild conditions. Our numerical experiments include simulation studies for comparing ℓ 0 -TF to ℓ 1 -TF and free-knot splines on several synthetic examples, and a real data application of time series segmentation on Hong Kong PM2.5 indexes. History: Accepted by Antonio Frangioni, Area Editor for Design & Analysis of Algorithms – Continuous. Funding: This work was supported in part by Hong Kong General Research Fund [No. 17306519]. C. Wen's research is partially supported by National Science Foundation of China [12171449] and Fundamental Research Funds for the Central Universities [WK3470000027, YD2040002019]. X. Wang's research is partially supported by National Natural Science Foundation of China [Grants 72171216, 12231017, 71921001, and 71991474], and the National Key R&D Program of China [No. 2022YFA1003803]. Supplemental Material: The e-companion is available at https://doi.org/10.1287/ijoc.2021.0313. The software that supports the findings of this study is available within the paper and its Supplemental Information (https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2021.0313) as well as from the IJOC GitHub software repository (https://github.com/INFORMSJoC/2021.0313). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/. [ABSTRACT FROM AUTHOR]

We extend the notion of globalized robustness to consider distributional information beyond the support of the ambiguous probability distribution. We propose the globalized distributionally robust counterpart that disallows any (respectively, allows limited) constraint violation for distributions residing (respectively, not residing) in the ambiguity set. By varying its inputs, our proposal recovers several existing perceptions of parameter uncertainty. Focusing on the type 1 Wasserstein distance, we show that the globalized distributionally robust counterpart has an insightful interpretation in terms of shadow price of globalized robustness, and it can be seamlessly integrated with many popular optimization models under uncertainty without incurring any extra computational cost. Such computational attractiveness also holds for other ambiguity sets, including the ones based on probability metric, optimal transport, ϕ-divergences, or moment conditions, as well as the event-wise ambiguity set. Numerical studies on an adaptive network lot-sizing problem demonstrate the modeling flexibility of our proposal and its emphases on globalized robustness to constraint violation. History: Antonio Frangioni, Area Editor for Design & Analysis of Algorithms—Continuous. Funding: Z. Chen was supported by [General Research Fund Grant 9043424, NSFC/RGC Joint Research Scheme N_CityU105/21] from the Hong Kong Research Grants Council. S. Wang was supported by the National Natural Science Foundation of China [Grants 71922020, 72171221, and 71988101, entitled "Econometric Modeling and Economic Policy Studies"] and the Fundamental Research Funds for the Central Universities [Grant UCAS-E2ET0808X2]. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information (https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2022.0274) as well as from the IJOC GitHub software repository (https://github.com/INFORMSJoC/2022.0274). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/. [ABSTRACT FROM AUTHOR]

A multidepot capacitated vehicle routing problem aims to serve customers' demands using a fleet of capacitated vehicles located in multiple depots, such that the total travel cost of the vehicles is minimized. We study a variant of this problem, the k-depot split delivery vehicle routing problem (or k-DSDVRP in short), for the situation where each customer's demand can be served by more than one vehicle, and the total number of depots, denoted by k ≥ 2 , is a fixed constant. This is a challenging problem with broad applications in the logistics industry, for which no constant ratio approximation algorithm is known. We develop a new approximation algorithm for the k-DSDVRP, ensuring an approximation ratio of (6 − 4 / k) and a polynomial running time for any fixed constant k ≥ 2. To achieve this, we propose a novel solution framework based on a new relaxation of the problem, a cycle splitting procedure, and a vehicle assignment procedure. To further enhance its efficiency for practical usage, we adapt the newly developed approximation algorithm to a heuristic, which runs in polynomial time even when k is arbitrarily large. Experimental results show that this heuristic outperforms a commercial optimization solver and a standard vehicle routing heuristic. Moreover, our newly proposed solution framework can be applied to developing new constant ratio approximation algorithms for several other variants of the k-DSDVRP with k ≥ 2 being a fixed constant. History: Accepted by Erwin Pesch, Area Editor for Heuristic Search & Approximation Algorithms. Funding: This work was supported in part by the National Natural Science Foundation of China [Grants 71971177, 71725001, U1811462], Research Grants Council of Hong Kong SAR, China [Grant 15221619], and Guangdong Basic and Applied Basic Research Foundation [Grant 2023A1515030260]. Supplemental Material: The e-companion is available at https://doi.org/10.1287/ijoc.2021.0193. The software that supports the findings of this study is available within the paper and its Supplemental Information (https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2021.0193) as well as from the IJOC GitHub software repository (https://github.com/INFORMSJoC/2021.0193). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/. [ABSTRACT FROM AUTHOR]

We study adjustable distributionally robust optimization problems, where their ambiguity sets can potentially encompass an infinite number of expectation constraints. Although such ambiguity sets have great modeling flexibility in characterizing uncertain probability distributions, the corresponding adjustable problems remain computationally intractable and challenging. To overcome this issue, we propose a greedy improvement procedure that consists of solving, via the (extended) linear decision rule approximation, a sequence of tractable subproblems—each of which considers a relaxed and finitely constrained ambiguity set that can be iteratively tightened to the infinitely constrained one. Through three numerical studies of adjustable distributionally robust optimization models, we show that our approach can yield improved solutions in a systematic way for both two-stage and multistage problems. History: Accepted by Pascal Van Hentenryck, Area Editor for Computational Modeling: Methods & Analysis. Funding: Financial support by the Early Career Scheme from the Hong Kong Research Grants Council [Project No. CityU 21502820], the CityU Start-Up Grant [Project No. 9610481], the CityU Strategic Research Grant [Project No. 7005688], the National Natural Science Foundation of China [Project No. 72032005], and Chow Sang Sang Group Research Fund sponsored by Chow Sang Sang Holdings International Limited [Project No. 9229076] is gratefully acknowledged. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information (https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2021.0181), as well as from the IJOC GitHub software repository (https://github.com/INFORMSJoC/2021.0181). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/. [ABSTRACT FROM AUTHOR]

75.6% of land comprising Hong Kong remains undeveloped according to the special administrative region's planning department. In turn, Hong Kong's constricted real estate, now estimated to be the world's costliest, has created eye-popping living arrangements historically and contemporarily. Denizens' colorful reputation and imagination for flouting city ordinances, zoning laws, and spatial management stand emblematic of tenacious self-sufficiency and a free-spirited brand of runaway capitalist initiative. Why is this conspicuous trademark of Hong Kong's societal fabric very much alive in the 21st Century? Why does this matter in a rapidly urbanizing world witnessing the ascension of mega-urban centers alongside ever-widening socioeconomic chasms? This paper intends to illuminate the peculiar origins and longevity of the KowloonWalled City, an urban monolith of notoriety and autonomy that blossomed in a semi-legal grey zone unencumbered under British protectorate rule for nearly a century. Parallels will connect the linear trajectory between Kowloon's hardnosed living to today's comparable Chungking Mansions and the hundreds of thousands of cage homes appearing in all corners of the city. This paper aims to answer why these residential paradoxes continue to function with efficiency and relevancy, posing solutions for indigent housing while exacerbating the stigma of social and economic ostracism. [ABSTRACT FROM AUTHOR]

Background: The new waves of COVID-19 outbreaks caused by the SARS-CoV-2 Omicron variant are developing rapidly and getting out of control around the world, especially in highly populated regions. The healthcare capacity (especially the testing resources, vaccination coverage, and hospital capacity) is becoming extremely insufficient as the demand will far exceed the supply. To address this time-critical issue, we need to answer a key question: How can we effectively infer the daily transmission risks in different districts using machine learning methods and thus lay out the corresponding resource prioritization strategies, so as to alleviate the impact of the Omicron outbreaks? Methods: We propose a computational method for future risk mapping and optimal resource allocation based on the quantitative characterization of spatiotemporal transmission patterns of the Omicron variant. We collect the publicly available data from the official website of the Hong Kong Special Administrative Region (HKSAR) Government and the study period in this paper is from December 27, 2021 to July 17, 2022 (including a period for future prediction). First, we construct the spatiotemporal transmission intensity matrices across different districts based on infection case records. With the constructed cross-district transmission matrices, we forecast the future risks of various locations daily by means of the Gaussian process. Finally, we develop a transmission-guided resource prioritization strategy that enables effective control of Omicron outbreaks under limited capacity. Results: We conduct a comprehensive investigation of risk mapping and resource allocation in Hong Kong, China. The maps of the district-level transmission risks clearly demonstrate the irregular and spatiotemporal varying patterns of the risks, making it difficult for the public health authority to foresee the outbreaks and plan the responses accordingly. With the guidance of the inferred transmission risks, the developed prioritization strategy enables the optimal testing resource allocation for integrative case management (including case detection, quarantine, and further treatment), i.e., with the 300,000 testing capacity per day; it could reduce the infection peak by 87.1% compared with the population-based allocation strategy (case number reduces from 20,860 to 2689) and by 24.2% compared with the case-based strategy (case number reduces from 3547 to 2689), significantly alleviating the burden of the healthcare system. Conclusions: Computationally characterizing spatiotemporal transmission patterns allows for the effective risk mapping and resource prioritization; such adaptive strategies are of critical importance in achieving timely outbreak control under insufficient capacity. The proposed method can help guide public-health responses not only to the Omicron outbreaks but also to the potential future outbreaks caused by other new variants. Moreover, the investigation conducted in Hong Kong, China provides useful suggestions on how to achieve effective disease control with insufficient capacity in other highly populated countries and regions. [ABSTRACT FROM AUTHOR]

Outdoor adventure education (OAE) is philosophically rooted in Western values, yet it has been implemented in non-Western cultures, such as East Asia. This paper examines how OAE functions in East Asia, through data from Hong Kong. Although some cultural differences are clear, there is no compelling evidence that OAE cannot provide benefits in Eastern contexts. The data in our example support the premise that OAE can be a viable and valuable medium for the development of social and intrapersonal skills and may serve as a complementary approach to traditional schooling in East Asia. Implications from this paper include better aligning OAE with schools and teachers, understanding the merits of relationships developed through OAE, and appreciating that some traditional OAE practices should be questioned when exported to different cultures. [ABSTRACT FROM AUTHOR]

This paper examines the determinants of foreign direct investment (FDI) from Singapore to two main host destinations: China and Hong Kong. It allows policy makers and researchers to understand the differences/similarities in the determinants of FDI from Singapore to a developing country, China, and a developed country, Hong Kong. Annual time series data covers the period 1994 to 2014 is used. Commonly used determinants, such as gross domestic product per capita of a host country, gross domestic product per capita of Singapore, real interest rate of a host country and trade openness of a host country are utilized to study Singapore's outward FDI (OFDI). Because the sample has only 21 observations, autoregressive distributed lag based bounds testing approach to cointegration developed by Pesaran, Shin & Smith (2001) is used to estimate cointegrating regression among these variables. This approach is an appropriate econometric estimation technique because the estimated long-run coefficients obtained from the reparameterization of an ARDL model are super-consistent even in small sample size. The main findings show that gross domestic product per capita of a host country attracts FDI from Singapore to each of these countries. It is also observed that higher interest rates in these two host countries attract Singapore's FDI. The degree of openness of China influences the flows of Singapore's FDI to China positively, but not for Hong Kong. It is a surprise that this empirical study is unable to find evidence that gross domestic product per capita of Singapore has an influence on its own FDI outflows. The overall results reveal that the motives of multinational corporations (MNCs) from Singapore to invest abroad typically differ between developing and developed economies, depending upon their respective competitive advantages. In general, MNCs invest in more advanced economies, such as Hong Kong, due to its purchasing power and market potential. Same goes for the developing markets, such as China, that consists of cheaper labor and large market opportunities. For the developing economies, trade liberalization is proved to be the pull factor that attracts MNCs. The more open an economy, the greater the attraction it has to MNCs. [ABSTRACT FROM AUTHOR]

Women are emerging as significant actors in international financial industries concentrated in metropolitan cities which function as national and international business hubs. Based on 17 in-depth interviews with Chinese women bankers in Hong Kong, where one finds the highest concentration of banking institutions in the world, this paper examines the interplay between locality, gender performance and the career mobility of women bankers. The author argues that branch location is embedded within hierarchical fields of power and leads to different client groups, and ultimately, to different opportunities for upward mobility. Women bankers in Hong Kong are skilled in displaying multiple identities by using differentiated styles of language and different tongues, or languages, when interacting with different client groups in different branches. This strategy involves evaluative interpretation of perception because clients themselves make class distinctions according to different service settings. Although mid-level management teams in the banking industry have recently been rapidly feminised, this paper demonstrates that the glass ceiling is still real and continues to exert its invisible, negative impact. The upward mobility of Chinese women bankers is often blocked by informal barriers deeply embedded in the social structure and culture of both local society and international companies. These structural barriers and their resultant structured disadvantages for women are the consequence of the intersection, and sometimes the collusion, of ethnic politics, business or capitalist interests and social norms. Factors and structural forces such as race, ethnicity and gender are intertwined with and compounded to produce deep and far-reaching effects that are often beyond the control of the individual actor. [ABSTRACT FROM AUTHOR]

• We compared the structural characteristics of 18 urban agglomerations in China. • Our framework contained analysis of 3 different scales based on 4 elements' flows. • Guangdong-Hong Kong-Macao urban Agglomeration had the greatest average flow (5.15). • Shandong Peninsula Urban Agglomeration had the best performance in overall network. • Cities with high centrality were in the bidirectional or main spillover subgroups. Flows of different elements among cities can affect urban organizational structures, leading to specific links between and roles for cities within urban agglomerations. Previous studies have mainly focused on flows produced by specific elements in a single urban agglomeration, and they cannot reveal differences in organizational structures affected by multiple elements among different urban agglomerations. Therefore we selected 18 typical urban agglomerations in China and explored their structural characteristics under comprehensive effects of four elements: economy, resources, population and technology, with gravity model and social network analysis. Guangdong-Hong Kong-Macao Urban Agglomeration had a maximum flow intensity of 5.15, this concentration range was the largest from 0.65 to 3.75, indicating that more elements flowed internally. Shandong Peninsula Urban Agglomeration had the largest network density at 0.412, the lowest efficiency at 0.567, and the lowest hierarchy at 0.000, showing that intercity relationships within SP were the tightest among the18 urban agglomerations. Geographical proximity and topological structure of subgroups proved that connections among subgroups were not complex, and cities of different provinces lacked close interactions. Furthermore, most of the key cities with high centrality indexes were municipalities directly under the Central Government or provincial capitals; these cities played important roles in networks and were distributed into "main spillover" and "bidirectional spillover" subgroups. This paper provides a unified analytical framework aimed at urban agglomerations that accounts for flows of multiple types of elements and explores urban organizational structures, and our results could provide scientific guidance for promoting the coordinated and sustainable development of urban agglomerations. [ABSTRACT FROM AUTHOR]

This paper explores the motivations and aspirations of African students who choose Hong Kong as their destination for university studies. Based on the findings of in-depth interviews with ten African students in Hong Kong, this research postulates that academic reputation and financial incentives are the two main motivations for attending university in Hong Kong. Other factors such as good teaching, research supervision, and treating Hong Kong as a stepping-stone to China also motivate some students. However, this paper identifies a general pattern that indicates most of the African students do not intend to stay behind in Hong Kong after graduation. While internationalization is a major strategic development of Hong Kong universities, there remain an insignificant number of African students on Hong Kong campuses. We suggest that recruiting more African university students can enhance the international profile of Hong Kong universities and strengthen academic internationalization at large. [ABSTRACT FROM AUTHOR]

The construction industry in Hong Kong has been exposed to serious housing production issues such as insufficient manpower, safety, environmental concerns and inefficient housing supply. Prefabrication housing production has shown as efficient construction model which enables to overcome these issues and it is applied in construction industry in Hong Kong. In this paper, hybrid modeling techniques that combine system dynamics and discrete event simulation are used to analyze the interrelationships of schedule risks within the six-day cycle assembly of prefabrication housing production. Moreover, a hybrid dynamic model is developed to simulate and evaluate the impact of schedule risks on the schedule performance of the six-day cycle assembly of PHP via the Anylogic software package. The resulting model is validated by data which is collected from a PHP project in Hong Kong. Based on the simulation results, the first most influential level contains five schedule risks, namely, inefficient verification of precast components because of ambiguous labels, misplacement on the storage site because of carelessness, owner crane breakdown and maintenance, slow quality inspection procedures, and inefficient design data transition that cause average schedule delays of more than 300 min. The second most influential level includes delay of the delivery of precast element to site, design information gap between designer and manufacturer, installation error of precast elements, and logistics information inconsistency because of human errors, with average schedule delays less than 300 min and greater than 200 min. Design change, low information interoperability between different enterprise resource planning systems, and inefficiency of design approval belong to the third level that imposes the least influence on the schedule delay of the assembly. This research contributes to the current knowledge of the management of prefabrication construction by developing an effective model that offers an in-depth understanding of how schedule performance of PHP is dynamically influenced by interrelationships of various risk variables. Also, it provides an experimental platform for simulating and analyzing schedule risks that significantly affect the schedule performance of the six-day cycle assembly of prefabrication housing production. Such critical schedule risks could be identified and managed prior to the implement of prefabrication housing production projects. Compared with traditional techniques, the hybrid dynamic model simultaneously considers macro and micro levels, thereby enabling project managers to gain a deeper insight into schedule management and acquire a multidimensional understanding of schedule delay. [ABSTRACT FROM AUTHOR]

Introduction: In view of the popularity of Internet usage in Hong Kong, an interactive web-based drug information platform entitled "Ask My Pharmacist - Online University Led drug Enquiry Platform" (AMPOULE) was launched in 2009 to better serve the needs of drug information in Hong Kong. This paper aimed to evaluate the utility of AMPOULE in improving drug-related knowledge among the public and to reassess the needs of the general public in Hong Kong.Methods: All enquiries sent via AMPOULE were reviewed. Demographic data, nature of questions and types of drug class covered were analyzed. The workload of pharmacists was examined with respect to the preparation time needed for the enquiry, the lag days to reply and also the timing of enquiry recipient.Results: 2122 enquiries were received from 2009 to 2017. Most enquirers were from Hong Kong (56.6%) and female gender (49.2%). 13% of the concerned subjects were aged over 61-year-old. The most frequent types of questions and medications covered were "Drug Ingredients and Indications" (28.0%) and Adverse Drug Reactions (26.8%) and "Cardiovascular Medication" (21.9%) respectively but these varied in different age groups or enquirer groups. The median time for preparation was 40.0 min (IQR: 25-65 min) while the median time lag was found to be 2.5 days (IQR: 1.0-5.0 days). The number of enquiries received was evenly distributed throughout the day except during 1:00 am to 9:00 am and 7:00 pm to 8:00 pm.Conclusion: AMPOULE has demonstrated that an online platform providing patient-oriented drug information service through the Internet is promising and further promotion is warranted. Current data suggested that the need of different age groups and enquirer groups are different and should therefore be individualized. [ABSTRACT FROM AUTHOR]

This paper looks at the changes that occurred in the rural area of the Sai Kung Peninsula in Hong Kong's New Territories from the 16th century, and uses it as a case-study to show the complex range of forces that can act on a locale. Throughout its history, land use and economic activities on the Sai Kung Peninsula have been driven to a great extent by non-local factors, including distant warfare leading to mass immigration and political decisions leading to mass emigration. However, once Hong Kong became an important outpost of Britain's colonial empire it became integrated into a global trade network and thus became sensitive to economic and technological changes taking place thousands of miles away. In the 20th century, the Sai Kung Peninsula developed in response to Hong Kong's growth as an international trade hub, finding its agricultural output overwhelmed by cheap foreign products, and its industry challenged by foreign technological advances. [ABSTRACT FROM AUTHOR]

The effect of state size on level of democratization has been a topic of interest to political scientists. However, studies have largely focused on democratic regimes, leaving unexplored the implications of state size for the regime persistence of hybrid regimes. This article compares two Chinese island cities with hybrid regimes through political analysis supplemented by interviews, and argues that a smaller regime is more likely to be authoritarian than a larger one. The case of Macau shows that the very small size of a 'microstate' helps central authorities to exercise political control, stifle political pluralism, and monopolize opinions, all of which strengthen regime persistence. In contrast, the case of Hong Kong shows that a merely 'small state', a larger political entity, creates political polarization, encourages political competition, and diversifies opinions, resulting in a more confrontational state-society relationship. This paper contributes to the literature by examining the effect of state size on regime persistence in hybrid regimes and explaining political development in Macau and Hong Kong from an alternative geopolitical perspective. [ABSTRACT FROM AUTHOR]

Hong Kong has numerous outlying islands that are relatively underdeveloped due to isolation from the urban core and are dependent on ferries. Concurrently, the Hong Kong Government has expressed a desire for outlying islands to be places for urban expansion and has proposed building more bridges, tunnels, and reclaimed land. Development of these fixed links may transform the outlying island communities' current ways of life. Ferry operators struggle to maintain efficient operation, fleet investments, improved services, and attract passengers while competing with fixed link transport modes. Urban ferry transport has been resurgent in parts of Europe, North America, and Australia, but not Hong Kong. This paper identifies a new typology of island communities according to connectivity based on available transport links. Using census and ferry statistics, the socioeconomic development of island communities is analysed. The transport problems faced by outlying islands are further conceptualised, and possible scenarios for socially sustainable island futures are proposed. [ABSTRACT FROM AUTHOR]

The Hospital Authority (HA) is a statutory body managing all the public hospitals and institutes in Hong Kong (HK). In recent decades, Hong Kong Hospital Authority (HKHA) has been making efforts to improve the healthcare services, but there still exist some problems like unfair resource allocation and poor management, as reported by the Hong Kong medical legislative committee. One critical consequence of these problems is low healthcare efficiency of hospitals, leading to low satisfaction among patients. Moreover, HKHA also suffers from the conflict between limited resource and growing demand. An effective evaluation of HA is important for resource planning and healthcare decision making. In this paper, we propose a two-phase method to evaluate HA efficiency for reducing healthcare expenditure and improving healthcare service. Specifically, in Phase I, we measure the HKHA efficiency changes from 2000 to 2013 by applying a novel DEA-Malmquist index with undesirable factors. In Phase II, we further explore the impact of some exogenous factors (e.g., population density) on HKHA efficiency by Tobit regression model. Empirical results show that there are significant differences between the efficiencies of different hospitals and clusters. In particular, it is found that the public hospital serving in a richer district has a relatively lower efficiency. To a certain extent, this reflects the socioeconomic reality in HK that people with better economic condition prefers receiving higher quality service from the private hospitals. [ABSTRACT FROM AUTHOR]

The paper reports a quasi-experimental study comparing the "traditional flipped classroom" pedagogical design with the "productive failure" (Kapur, 2016) pedagogical design in the flipped classroom for a 2-week curricular unit on polynomials in a Hong Kong Secondary school. Different from the flipped classroom where students are provided video clips with new concepts and associated procedures to review at home before solving problems in class, the "productive failure" pedagogical design in the flipped classroom worked the other way around. Supported by mobile technologies, students explored, discussed and solved problems related to the new concepts first in class even though they might come across failures, followed by consolidating the concepts and associated procedures using video clips at home. The pedagogical design is referred to as "productive failure-based flipped classroom" in this study. The study was carried out in two Grade 7 classes: one with "traditional flipped classroom" and one with the "productive failure-based flipped classroom". Findings show that both classes had significant improvement in procedural knowledge. However, regarding conceptual knowledge, students in the "productive failure" condition performed better than those in traditional flipped classroom. This suggests that the "productive failure-based flipped classroom" pedagogical design may be better able to improve students' problem solving skills. [ABSTRACT FROM AUTHOR]

In order to achieve the purpose of sealing water between adjacent jacked pipes in construction of long-distance and large-section tunnel, an innovative method called Freeze-Sealing Pipe Roof (FSPR) was applied to the Gongbei tunnel, which is a key part of Hong Kong-Zhuhai-Macau Bridge in China. Since the pre-constructed jacking pipes provides great convenience for flexible placement of freezing tubes inside, it is crucial to study the temperature field of different freezing states. This paper first established a new mathematical model considering radial offset of jacking pipe according to the practical engineering, and then the analytical solution to steady-state temperature field was also derived. Moreover, temperature distribution of four typical cross-sections were analyzed to evaluate the freezing effect on different paths. Results show that the analytical results are in good agreement with the numerical results, and the quasi-double-circle freezing model can be well applied to the practical problem of radial offset. Soil between steel pipes will be lowered to a sufficiently low temperature and form a fairly reliable water-sealing curtain. By designing the radial offset between freezing tubes in solid and hollow pipes, the freezing effect can be better ensured. The conclusions have important guiding significance for design and construction of FSPR method in future projects. • Temperature field of a special double-circle-piped freezing model is solved analytically. • The boundary separation property of the harmonic equation is used to solve the heat conduction problem. • The accuracy of complex analytical expressions is verified by numerical simulation. • Water sealing effect of FSPR method considering radial offset of jacking pipes is analyzed. [ABSTRACT FROM AUTHOR]

In 2012-2014, our laboratory had investigated a total of 9 suspected front blind spot crashes, in which the medium and heavy goods vehicles pulled away from rest and rolled over the pedestrians, who were crossing immediately in front of the vehicles. The drivers alleged that they did not see any pedestrians through the windscreens or the front blind spot mirrors. Forensic assessment of the goods vehicles revealed the existence of front blind spot zones in 3 out of these 9 accident vehicles, which were attributed to the poor mirror adjustments or even the absence of a front blind spot mirror altogether. In view of this, a small survey was devised involving 20 randomly selected volunteers and their goods vehicles and 5 out of these vehicles had blind spots at the front. Additionally, a short questionnaire was conducted on these 20 professional lorry drivers and it was shown that most of them were not aware of the hazards of blind spots immediately in front of their vehicles, and many did not use the front blind spot mirrors properly. A simple procedure for quick measurements of the coverage of front blind spot mirrors using a coloured plastic mat with dimensional grids was also introduced and described in this paper. [ABSTRACT FROM AUTHOR]

Increase in cooling energy usage of the residential sector in Hong Kong has been moderate in the most recent ten years (2004–2013). Factors and drivers responsible for this are of interest to policy makers in search of performance improvement but such information is not available in extant literature. This paper reviews the policy instruments introduced in Hong Kong during this period of time and examines the different engineering factors contributing to improvements in cooling energy efficiency. Whether the policy instruments have been instrumental in bringing about changes in engineering design and thus improvement in cooling energy efficiency is evaluated on the basis of the equipment and building envelope characteristics of 64 residential developments in Hong Kong. Different statistical analyses reveal that the use of more energy efficient room air-conditioning units (COP), smaller window-to-wall ratios (WWR) and walls with higher U-values are the engineering factors (WallU) that have contributed to moderation of growth of energy consumption; these were driven by policies introduced by the Hong Kong Government. Regarding the sensitivity of the three engineering factors, it was found that COP was the highest amounting to 0.455, followed in descending order by WallU and WWR. Their sensitivities were 0.289 and 0.006, respectively. [ABSTRACT FROM AUTHOR]

The Shanghai-Hong Kong Stock Connect has been in operation for more than a year. It is predictable that with the implementation of this scheme, cross-border securities disputes between the Mainland and Hong Kong will be on the rise. In resolving these disputes, one of the most important problems is the determination of substantive law that should apply to them. This paper makes feasible proposals to harmonize the choice of law rules regarding cross-border securities disputes under the Shanghai-Hong Kong Stock Connect with due reference made to the approaches adopted by the Hague Convention on the Law Applicable to Certain Rights in Respect of Securities Held with an Intermediary and the Uniform Commercial Code of the US. [ABSTRACT FROM AUTHOR]

ABSTRACT Heavy rain events or rainstorms of various scales often occur in Hong Kong from April to September. In extremes cases, they lead to serious landslides and flash floods resulting in loss of life, and damage to property and infrastructure. With climate change, extreme rain events are projected to be more frequent and more intense in this region. A system to gauge and label the severity of rainstorms would be useful for identifying and communicating extreme conditions in warning and disaster prevention operations. In parallel, a better understanding of the characteristics of rainstorms would also be important for impact assessments and engineering design purposes. This paper formulates a practical framework to index the magnitude and severity of rainstorms in Hong Kong. An index termed as the Severity Index combining the magnitude of different rainstorm attributes is devised for quantifying the overall severity of rainstorms. This index is flexible to allow tuning for specific applications. [ABSTRACT FROM AUTHOR]

Introduction: The 2019 coronavirus disease (COVID-19) is a global health crisis that originated in China. As an adjacent city to the origin of COVID-19, Hong Kong has been facing different public health challenges raised by the epidemic. Objectives: This paper examined the prevalence of common physical symptoms, psychological symptoms, somatic symptoms, and health anxiety among the Hong Kong youth population. Methods: HKYES is an on-going territory-wide epidemiological study collecting youth mental health data with randomly stratified sampling. Participants aged 15-24 years were to complete a physical symptom checklist, Depression, Anxiety and Stress Scale (DASS-21), Insomnia Severity Index (ISI), Patient Health Questionnaire-15 (PHQ-15), and Short Health Anxiety Inventory (SHAI). Results: A total of 594 participants have completed the survey since April 2020. The three most common physical symptoms were headache (n=106, 17.8%), fever (n=94, 15.8%) and fatigue (n=78, 13.1%). The mean scores of DASS depression, anxiety and stress subscales were 7.98 (SD 8.14), 5.81 (SD 6.32), and 8.83 (SD 7.93) respectively. Among all, 135 (22.8%) participants reported moderate to severe levels of depressive symptoms, 133 (22.4%) reported moderate to severe levels of anxiety symptoms, and 71 (12%) reported moderate to severe levels of stress. There were 40 (6.7%) and 60 (10.1%) participants showing significant levels of insomnia and somatic symptoms, while around one-third of the participants reported a high level of health anxiety. Conclusions: Youth is at risk of severe psychological impact during the coronavirus. Monitoring the mental health trajectory for youth should become routine practice during times of crisis. [ABSTRACT FROM AUTHOR]

The concession period is one of the critical factors in the arrangement of a build-operate-transfer contract. For infrastructure that has major strategic, economic, and social effects, the concession period should balance the interests among the private investors, the government, and the users. However, existing research has more frequently discussed economic benefits rather than social welfare. In this regard, this paper proposes an improved model based on the traditional concession model by taking into account the case that the government might lower the service price in the posttransfer period to increase social welfare. This paper also introduces the optimal pricing methods for both concession and posttransfer period. The proposed methodology suggests a narrower concession interval, which helps improve the negotiation efficiency between the government and the private investor to a certain extent. The application of the proposed model is demonstrated by a case study of Western Harbor Tunnel in Hong Kong, and the outcome shows that a significant improvement was made when taking into account social welfare. [ABSTRACT FROM AUTHOR]

In 2001, the Hong Kong government implemented a concession policy allowing green and amenity features to be exempted from gross floor area (GFA) calculations in new residential properties. There have recently been community concerns that developers are using this policy to substantially increase the floor area of buildings. In the 2010-2011 policy address, the Hong Kong government decided to tighten the existing policy. This paper attempts to estimate the efficacy of the proposed GFA concession policy. Five case studies are selected to demonstrate the change in GFA concession. It is found that the proposed GFA concessionary has a positive effect in controlling the height and bulk of buildings, and a reduction of approximately 4.58% GFA concession can be achieved, compared to the existing policy. However, some negative effects are also created, including the increase of housing price (or the drop of land auction price) and the discouragement of green features. [ABSTRACT FROM AUTHOR]