107 research outputs found
A STUDY ON THE USE OF LIFEFORM DIVERSITY MEASURES IN THE ASSESSMENT OF CORAL REEFS
No full textBachelor'sBACHELOR OF SCIENCE (HONOURS
Investigation into the Promotion and Instruction of Chinese Traditional Music in Liaocheng Peiwen School of Peking University
No full textThis research investigates the promotion and instruction of Chinese Traditional music in Liaocheng Peiwen School of Peking University. The first author, an alum with a decade of pedagogical experience, examined the challenges faced by private schools in providing tailored regulatory frameworks for Chinese Traditional music education. We share practical experience, drawing on the successful establishment of the school-based course "Chinese Folk Music and Geography." As the course is offered each year during the geography exam for students in their second year of junior high school, singing folk songs while learning geography enables students to explore China's beautiful landscapes while broadening their horizons. Students can understand the connection between folk music and geography, assisting their preparation for the exam
Explore a new book discovery experience in the public library
No full textNowadays, a public library is no longer a place just for the collection of books. It has offered multiple functions to take the responsibility of being a public cultural institution for all citizens. However, in the Netherlands, libraries are losing their members, especially young adults. With the development of technology, a public library is no longer the only choice for books. Libraries are encountering a challenge to attract young people back. They need to strive for providing new kinds of public services to attract this potential new audience.Westfriese Bibliotheken is one of these libraries which has 10 decentralized community libraries in 6 places in the north of the Netherlands. Westfriese Bibliotheken is facing a challenge to reach a bigger group of the generation of youngsters who think a public library is a dull place to go. To narrow down the scope, the book discovery experience for young adults between 18-25 years old was focused. Augmented reality as the technology this project worked with has been proved to benefit the library context.Hence, the objective of this thesis is to explore a new book discovery experience for young adults in the public library in Stede Broec.From the theoretical study (chapter 2) about the book discovery behavior, the behavior pattern was investigated and worked as the design requirements. User research (chapter 3) was conducted to understand the current book discovery experience in the context through contextmapping. It discovered users' concerns and expectations about the book discovery experience. Moreover, the opportunity of this project: designing a new book discovery experience to facilitate serendipity was concluded based on user research findings. Under the framework of the serendipity theory (chapter 4), design opportunities for facilitating serendipity in the current library were gathered. The study on augmented reality (chapter 5) helped to define design qualities and technologies that this project can make use of.With the research insights, a design goal with three design qualities (fascinating, playful, and inviting) and relevant design requirements were formulated (chapter 6). They contributed as a guideline to the design solution.Ideas were gathered through a creative session and based on these ideas three initial concepts were generated. Concepts were evaluated and iterated with users, clients, and fellow students. The final design outcome is a phone-based AR application with two main parts: exploring and browsing parts. It offers both basic and additional information about books to stimulate users to experience serendipity in the public library. Finally, an evaluation test was conducted to validate if the final design can fulfill the design goal. The final design achieves a good usability and desirability performance evaluated by 6 participants in the library. The evaluation test demonstrated that the additional information about books and interaction between the physical and digital world can let users feel fascinated, invited, and playful during the book discovery experience.Design for Interactio
Distributed Optimization in Electric Power Systems: Partitioning, Communications, and Synchronization
No full textTo integrate large volumes of renewables and use electricity more efficiently, many industrial trials are on-going around the world that aim to realize decentralized or hierarchical control of renewable and distributed energy resources, flexible loads and monitoring devices. As the cost and complexity involved in the centralized communications and control infrastructure may be prohibitive in controlling millions of these distributed energy resources and devices, distributed optimization methods are expected to become much more prevalent in the operation of future electric power systems, as they have the potential to address this challenge and can be applied to various applications such as optimal power ow, state estimation, voltage control, and many others. While many distributed optimization algorithms are developed mathematically, little effort has been reported so far on how these methods should actually be implemented in real-world large-scale systems. The challenges associated with this include identifying how to decompose the overall optimization problem, what communication infrastructures can support the information exchange among subproblems, and whether to coordinate the updates of the subproblems in a synchronous or asynchronous manner. This research is dedicated to developing mathematical tools to address these issues, particularly for solving the non-convex optimal power flow problem. As the first part of this thesis, we develop a partitioning method that defines the boundaries of regions when applying distributed algorithms to a power system. This partitioning method quantifies the computational couplings among the buses and groups the buses with large couplings into one region. Through numerical experiments, we show that the developed spectral partitioning approach is the key to achieving fast convergence of distributed optimization algorithms on large-scale systems. After the partitioning of the system is defined, one needs to determine whether the communications among neighboring regions are supported. Therefore, as the second part of this thesis, we propose models for centralized and distributed communications infrastructures and study the impact of communication delays on the efficiency of distributed optimization algorithms through network simulations. Our findings suggest that the centralized communications infrastructure can be prohibitive for distributed optimization and cost-effective migration paths to a more distributed communications infrastructure are necessary. As the sizes and complexities of subproblems and communication delays are generally heterogeneous, synchronous distributed algorithms can be inefficient as they require waiting for the slowest region in the system. Hence, as the third part of this thesis, we develop an asynchronous distributed optimization method and show its convergence for the considered optimal power flow problem. We further study the impact of parameter tuning, system partitioning and communication delays on the proposed asynchronous method and compare its practical performance with its synchronous counterpart. Simulation results indicate that the asynchronous approach can be more efficient with proper partitioning and parameter settings on large-scale systems. The outcome of this research provides important insights into how existing hardware and software solutions for Energy Management Systems in the power grid can be used or need to be extended for deploying distributed optimization methods, which establishes the interconnection between theoretical studies of distributed algorithms and their practical implementation. As the evolution towards a more distributed control architecture is already taking place in many utility networks, the approaches proposed in this thesis provide important tools and a methodology for adopting distributed optimization in power systems.</p
Sign-Balanced Pattern-Avoiding Permutation Classes
No full textA set of permutations is called sign-balanced if the set contains the same
number of even permutations as odd permutations. Let be the set of permutations in the symmetric group
which avoids patterns . The aim of this
paper is to investigate when, for certain patterns , is sign-balanced for
every integer . We prove that for any , if is
sign-balanced except , then is sign-balanced for every integer . In addition, we
give some results in the case of avoiding some patterns of length
Transformation Path of Fresh Food Enterprises’ Supply Chain in the New Retail Era——Double Case Study Based on Baiguoyuan and Daily Youxian
No full textDynamic Evaluation of Water Utilization Efficiency in Large Coal Mining Area Based on Life Cycle Sustainability Assessment Theory
No full textCoal mining enterprises have a variety of water sources, complex drainage structures, long production chain, and many links, which lead to uncoordinated water utilization and low water efficiency. Taking a large coal mining area of China as an example, a dynamic model was established to evaluate the water utilization efficiency based on the Life Cycle Sustainability Assessment (LCSA) theory. In the model, the influence of five aspects (including resources, economy, technology, society, and environment) and 19 factors was considered. The game theory method was adopted to calculate the fusion weights of the 19 factors according to the analytic hierarchy process and CRITIC method. The CW-VIKOR method was used to explain the dynamic evaluation results of water efficiency in the coal mining area. The results show that the environmental impacts of the mining system mainly come from three aspects: regional drainage, domestic sludge landfill and disposal, and water system electricity consumption. Electricity consumption in water systems has the greatest environmental impact, accounting for about 73%, regional drainage for about 26%, and domestic sludge landfill and disposal for about 1%.The CW-VIKOR approach can harmonize the interrelationships among resources, economy, technology, society, and environment. It is an effective method for LCSA of water resource in the coal mining area. The reliability of the evaluation results is high and close to the actual situation. The dynamic model established in this paper is also applicable to other coal mine areas, and only the factor weights need to be modified according to the specific characteristics of each coal mine. The model can provide guidance for optimal exploitation and allocation of coal mine water resources
On the permutations that strongly avoid the pattern 312 or 231
No full textIn 2019, B\'ona and Smith introduced the notion of \emph{strong pattern
avoidance}, that is, a permutation and its square both avoid a given pattern.
In this paper, we enumerate the set of permutations which not only
strongly avoid the pattern or but also avoid the pattern ,
for and some . One of them is to give a positive
answer to a conjecture of Archer and Geary
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