65 research outputs found
How we failed in context: A text-mining approach to understanding hotel service failures
No full textService failure is inevitable. Although empirical studies on the outcomes and processes of service failures have been conducted in the hotel industry, the findings need more exploration to understand how different segments perceive service failures and the associated emotions differently. This approach enables hotel managers to develop more effective strategies to prevent service failures and implement more specific service-recovery actions. For analysis, we obtained a nine-year (2010–2018) longitudinal dataset containing 1224 valid respondents with 73,622 words of textual content from a property affiliated with an international hotel brand in Canada. A series of text-mining and natural language processing (NLP) analyses, including frequency analysis and word cloud, sentiment analysis, word correlation, and TF–IDF analysis, were conducted to explore the information hidden in the massive amount of unstructured text data. The results revealed the similarities and differences between groups (i.e., men vs. women and leisure vs. business) in reporting service failures. We also carefully examined different meanings of words that emerged from the text-mining results to ensure a more comprehensive understanding of the guest experience
Canadians' travel knowledge acquisition during the pandemic: A cognitive mediation model approach
No full textThis study aimed to improve Canada's preparedness to rejuvenate the economy in public health crises by understanding how potential tourists acquire knowledge using the cognitive mediation model. We examined the effect of media motivations (i.e., surveillance gratification and anticipated interaction) in predicting two types of subjective knowledge (i.e., pandemic knowledge and travel health knowledge) through the mediation of media attention and elaboration. The study results supported all hypotheses except for the relationships between surveillance gratification and media attention, and media attention and travel health knowledge. This study provides implications for destination marketing organizations to understand Canadians' travel decisions during the pandemic.Mount Saint Vincent UniversityRapid-Response Internal Researc
Adapting Consumer Report's product evaluation methods for particle removal, gravity non-electric and reverse osmosis water filters in the Indian marketplace
No full textThesis: S.M., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.Cataloged from PDF version of thesis.Includes bibliographical references (pages 113-115).Household Water Treatment and Storage (HWTS) products provides households that are drinking unimproved water supplies with a first line of defense against contaminants in their drinking water and those drinking improved water supplies with an additional barrier against potential risks. With the global water crisis becoming more and more severe, evaluation of HWTS technologies and products has become crucial to ensure they are used to remove impurities effectively. The goal of this thesis was to evaluate household water filters in the Indian marketplace as part of a larger research and technology evaluation to investigate the utilization and performances of different water filter models in both lab and field settings. This was achieved by comparative testing and research work done at Consumer Reports (CR) Headquarters in Yonkers, NY. This evaluation included the testing of three categories of filters: Conventional Particle Removal (cloth and mesh), Gravity Non-Electric (GNE) and Reverse Osmosis (RO) water filters. In total, 16 models were tested. The challenge water for all filter testing had these characteristics: 40+/-10 NTU turbidity and 1500+/-150mg/L total dissolved solids (TDS). When testing E.coli removal, deionized water was used as the base water and the concentration of E. coli was 10⁵ to 10⁶ MPN (Most Probable Number)/100mL. The comparative testing attributes that were evaluated include: E.coli removal, turbidity removal, TDS removal, clean water flow rate, RO % recovery, and filter lifetime with the end-of-life defined as when flow rate <1 L/hr. As a result of this product evaluation, the author determined that: 1) Cloth and mesh filters had limited effectiveness in reducing contaminants; 2) GNE filters had much better performance than cloth and mesh filters, but none of them had outstanding performance; 3) RO filters were shown to be quite effective in reducing turbidity (greater than 99.5%), TDS (greater than 97%), and E.coli (greater than 99.9999%). But, they produce a large amount of wastewater (around 3/4 of the feed water) which is a huge waste of precious water and a sustainability concern especially in a water scarce region.by Shuyue Liu.S.M
How might human experience inform AI systems
No full textThe problem we want to addressAI(Artificial intelligence) is diving into people’s lives as its algorithm continues to iterate. However, the algorithmic and quantitative systems do not seem to access people’s experiences, which always include emotional and qualitative factors. How can an AI system understand people’s feelings? How can an AI system like GANs optimize for meaningful human values, like beauty?Our approachIn this project, I mainly build two approaches for designers to translate the human experience into GANs. Starting from the exploration of GANs, I investigate their potential chances to “understand” human experience. Then, the qualitative researchon human experience reveals the aesthetic factors influencing people’s feelingsabout GANs‘ output. Through the interviews, some pain points from AI productdesigners are concluded. Combining the exploration results in those three scopes, Ihypothesize that retraining with the highly-rated images and building new computational models to iterate the factors from the human evaluation can help designers inform the AI system about the human experience. I cooperated with CSE students and proposed two approaches- CURATION APPROACH and ALGORITHMICAESTHETIC APPROACH- based on the above assumptions. The build process demonstrates the achievability of the assumptions. In the evaluation part, the retrained images in both methods are rated higher than the original ones. Both approaches are proved to be practical and feasible.Our resultFor the curation approach, all produced models with highly-rated images outperformed the original model. The original model’s score is 0.2. When replacing 500,1000,2985 highly-rated images into the input dataset, their scores increased to 0.245, 0.269, and 0.255. For the algorithmic aesthetic approach, we select three categories of images(coastline, forest/desert, arctic). In each category of images, three factors are selected to improve. Among the nine groups whose corresponding factors are iterated by algorithms, eight groups’ new images are rated higher by people than the original images. The curation and algorithmic aesthetic approaches are verified to help inform AI systems of human experience.Potential impactFollowing the curation and algorithmic approaches, designers can successfully inform GANs about people’s aesthetic evaluation of their images. Using the human experience to improve AI systems is a starting point. It also proves the importance of the human experience for AI and provides a template for designers in all AI fields to inform their AI systems of human experience.Design for Interactio
Analysis of Shear Crushing Behavior of Graded Calcareous Sand in Building Applications
No full textCalcareous sand, a critical construction material in reef engineering and building foundations, possesses unique internal microstructures and inherent mechanical properties. Given these characteristics, it is essential to thoroughly evaluate its strength under various loading conditions to ensure its reliability in building applications. This study examines the strength, deformation, and failure characteristics of calcareous sand through consolidated drained shear failure tests using a GDS stress path triaxial apparatus. The effects of shear rate, particle gradation, and compactness are systematically investigated to assess their impact on structural stability in building foundations and load-bearing applications. The results indicate that at low confining pressures, calcareous sand exhibits strain softening, whereas at higher confining pressures, strain hardening is observed. For samples with the same gradation, both peak deviatoric stress and failure strain increase linearly with confining pressure. The volume strain evolution during shear follows three stages: shear shrinkage, shear dilatancy, and stabilization. At low confining pressures, dilatancy is favored, while high confining pressures promote shrinkage. Additionally, under constant confining pressure, peak strength increases and failure strain decreases linearly with compactness. Increasing the loading rate from 0.01 to 0.1 mm/min results in a slight increase in the friction angle, with minimal impact on cohesion. Particle gradation plays a significant role in determining the shear strength of calcareous sand, as its effects vary depending on the combination of compactness and gradation. These findings provide valuable insights for the design and construction of stable building foundations, roadbeds, and other load-bearing structures in reef engineering and coastal developments, where calcareous sand is widely used
Re-conceptualizing the ideal homes in rural China: an actor-network theory approach
No full textAbstract With the shift in relational ontology, the concept of home is interpreted as a dynamic and relational process, in which both human and non-human elements need to be valued. Adopting ANT (actor-network theory) as an approach, this article reveals the interactive relationship and translation process between urban-rural migrants and rural heterogeneous actors (including farmland, landscapes, local people, means of subsistence, and technological facilities) in the connection of ideal home networks. It involves three steps of translation between actors, namely problem presentation of key actors, enrollment and benefit granting by key actors, and negotiation of “obligatory passage points” (OPP) based on actors’ common goals. Based on a two-year qualitative research of 18 interviewees, this article demonstrates how migrants adapt to the countryside through enrollment and benefit granting, and how sustainability and recyclability become common interests and OPP for actors in homemaking. The article argues that ANT provides a descriptive focus on how rural life has transformed from a backward neighborhood or abstract nostalgia to a harmonious new home that blends traditional culture, ecological ideas, and modern technology in the context of China. The study also points out that in the process of translating interests between actors, the human-land relationship still shows complexity and instability. Future research needs to pay more attention to the role of government officials and governance policies in the building of home networks
Green Distribution Route Optimization of Medical Relief Supplies Based on Improved NSGA-II Algorithm under Dual-Uncertainty
No full textWith growing concerns about environmental issues, sustainable transport schemes are receiving more attention than ever before. Reducing pollutant emissions during vehicle driving is an essential way of achieving sustainable transport plans. To achieve sustainable transport and reduce carbon emissions, on the premise of ensuring rescue timeliness, this research proposes a multi-objective distribution route optimization model considering the minimization of transportation cost and transportation risk under dual-uncertainty constraints, providing a practical framework for determining the optimal location of rescue centers and distribution routes in emergencies using fuzzy theory. First, this paper proposes objective functions that innovatively take into account the congestion risk and accident risk during the distribution of medical supplies while introducing the carbon emission cost into the transportation cost and using the fuzzy demand for supplies and the fuzzy traffic flow on the roads as uncertainty constraints. Then, this paper designs a multi-strategy hybrid nondominated sorting genetic algorithm (MHNSGA-II) based on the original form to solve the model. MHNSGA-II adapts a two-stage real number coding method for chromosomes and optimizes the population initialization, crowding distances selection, and crossover and mutation probability calculation methods. The relevant case analysis demonstrates that, compared with the original NSGA-II, MHNSGA-II can decrease the transportation cost and transportation risk by 42.55% and 5.73%, respectively. The sensitivity analysis verifies the validity and rationality of the proposed model. The proposed framework can assist decision makers in emergency logistics rescue
Convention emergence in multi-agent systems
No full textPh.D.Social conventions, such as greeting rituals, wedding customs and table manners, guide people how to behave appropriately. The concept of social conventions has attracted much attention in multi-agent system research, in that they may regulate agents’ behaviours, and facilitate coordination among agents. In this thesis, we study how some features of real-life multi-agent systems affect convention emergence. We consider four specific scenarios:• We consider that agents are partitioned into compact communities, and hypothesise that diverse local conventions emerge in the communities. A definition of local conventions, and two quantitative metrics measuring their strength and diversity are provided. We show that in these systems, agents achieve coordination via establishing diverse local conventions. Moreover, we explore the factors that influence the speed of local convention emergence.• We note that different agents may tend to establish different conventions, although convention emergence is in their common interest. We model such scenarios to be competitive-coordination games. We hypothesise that conventions may not emerge from this types of games, and present the option of compromise to address this problem. Experimental results confirm this hypothesis. In particular, it is shown that as a side benefit, social unfairness is also significantly reduced.• We explore convention emergence from agents’ repeated n-player coordination games. We distinguish the gist representation of the observations of agents. A novel learning method that utilises gist representation is proposed. It is shown that the proposed method establishes conventions much faster than the learning methods that make use of verbatim representation. In addition, the use of gist trace derived at a low level of abstraction further accelerates convention emergence.• To promote the emergence of cooperation from repeated prisoner’s dilemma games, we consider agents may care for social values. For each action, an agent weigh the perceived social value and the received payoff, based on its own social value orientation. Experimental results show that prosocial orientations, in contrast to proself orientations, greatly promote the emergence of cooperation, especially in homogeneous prosocial systems and dynamic systems with the initial orientations are prosocial.In this thesis, we also propose a theoretical model for convention emergence. We consider a specific setting in which each agent uses Q-learning with Boltzmann exploration. Using mean field theory, we derive a system of four equations to formally describe how the population evolves as time goes forward. We verify our model through comparisons with agent-based simulations on typical symmetric games.社會規範（比如問候語，婚禮習俗和就餐禮儀）指引著我們每天的日常生活。社會規範這個概念最近受到多智能體系統研究領域的廣泛關注。研究者認為在多智能體系統中引入社會規範能幫助約束智能體的行為，從而更好實現智能體之間的協同工作。在這份論文中，我們對社會規範的形成如何受到一些現實因素的影響展開研究。我們具體考慮了以下四個場景。我們考慮多智能體系統具有社區結構，即智能體被劃分成若干個社區。我們猜想在這種情況下，每個社區都會建立各自的局部社會規範，一個全局的社會規範並不會產生。為了驗證我們的猜想，我們對局部社會規範進行了定義，並提出了兩種量化指標來衡量局部社會規範的強度和多樣性。我們的實驗結果證實了我們的猜想。並且，我們研究了社區結構的各個特徵如何影響局部社會規範的行程速度。我們考慮在一個多智能體系統中，不同的智能體可能傾向於建立不同的社會規範。我們把智能體在這種場景下的交互建模成競爭-協同博弈。我們猜想當智能體在進行重復的競爭-協同博弈時，社會規範可能不會在系統中形成。為了解決這個問題，我們提出為每個智能體提供一個進行妥協的選項。如果兩個智能體在進行博弈時同時選擇了妥協，那兩個智能體都會得到一個較為可觀的收益。實驗結果表明了在引入妥協這個選項後，社會規範更容易形成，並且社會公平性得到了提升。我們考慮智能體可能通過多邊協同博弈來建立社會規範。為了促進社會規範的形成，我們參考人類記憶的方式（模糊痕跡記憶理論），提出了基於模糊痕跡的強化學習方法。實驗結果表明我們提出的方法和基準方法以及目前最先進的方法相比，能在更短時間內建立社會規範。並且，如果智能體對模糊痕跡進行進一步的抽象化處理，我們提出的方法的優勢將更為明顯。我們考慮社會規範在智能體進行囚徒困境博弈時的形成。我們假設智能體能感知到每個動作背後的社會價值，並根據自身的價值傾向來平衡社會價值和自身利益，從而作出決策。實驗結果表明親社會的價值傾向能促進對社會有利的規範的形成。這種促進現象在同質化的多智能體系統以及基於經歷動態更新價值取向的多智能體系統中更為明顯。在這份論文中，我們還為社會規範的形成提出了一個理論模型。我們假設每個智能體都使用Q-學習方法並用波茲曼方法進行探索。我們通過應用平均場理論使得整個系統的演變能用四條式子進行描述。其中一條式子反映了隨著時間變化，系統中Q值分佈是如何變化的。我們通過比較理論模型和模擬實驗得出的結果對我們的模型進行驗證。Hu, Shuyue.Thesis Ph.D. Chinese University of Hong Kong 2020.Includes bibliographical references (leaves 127-139).Abstracts also in Chinese.Title from PDF title page (viewed on 21 May, 2021)
The pseudo-limit problem existing in electromagnetic radiation transmission and its mathematical physics principle analysis
No full textIn the study of electromagnetic radiation transmission for large airflow layers, it is found that not all electromagnetic waves are capable of forming waveguide propagation, and have a limit value problem. This is because whether electromagnetic waves propagating in the atmosphere can be captured by the atmospheric waveguide generated under specific meteorological conditions into the waveguide layer, depending on the wavelength (frequency) of the electromagnetic wave, the relative position of the emission source and the evaporating waveguide. And parameters such as the emission angle of the source. When the angle of incidence of the sun and the angle of observation are at a horizontal level, the amplitude of the electromagnetic radiation reflection is not unique. From a mathematical point of view, the limit value is not unique or the limit value is discontinuous, which is called the pseudo limit problem. This electromagnetic transmission pseudo-limit problem is a mathematical physics principle that ignores the physical principles implied in electromagnetic radiation. Based on this background, the paper studies the influencing factors of the pseudo-limit problem of electromagnetic transmission in large airflow layer, and analyzes the mathematical physics principle in the pseudo-limit problem by using Snell’s optical law
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