297 research outputs found
A synthetic aperture telescope based on a pair of gratings
No full textA synthetic aperture is an effective approach to enhancement of the resolution of telescopes. In this paper, a new method to improve the resolution by using a pair of gratings is proposed. It allows collection of parts of the light diffracted from the object which could not previously reach the imaging device. This method improves the resolution and light energy utilization ratio of telescopes without introducing new chromatic aberration. An experiment for resolution testing was carried out and the feasibility and availability of the method were verified
Characterization of A Mutator Organelle DNA Polymerase and Its Application to Mutate the Chloroplast Genome
No full textDevelopment of a WiFI based human activity detection and recognition system
No full textIn today's era, with the rapid development of information technology, people are increasingly inseparable from WIFI. WIFI seems to have become an indispensable part of our lives. Research on WIFI has also attracted more and more attention from the industry. Among them, WIFI-based human behavior recognition has gradually become a hot spot in the research of the Internet of Things.
Human behavior recognition (HBR) is very useful in our daily lives, and its application scenarios are also very wide, such as early warning reminders, intelligent security, patient monitoring systems, etc. Therefore, it is of great significance to study different methods of human behavior recognition. The most well-known method is machine vision, which collects video information through a camera system, and then uses image processing related algorithms to realize behavior recognition. Another method is to allow the detected person to wear sensors. This method mainly detects the subtle activity information of the human body, such as changes in joints or fingers. Although this method can guarantee accuracy, there are problems such as personal privacy, system complexity, and expensive equipment. Therefore, there are a lot of limitations in practical use.
Thus, the wireless HBR system is proposed, such as ultra-wideband (UWB) based human behavior recognition. Since WIFI is more common in daily life, human behavior recognition based on WIFI has been paid more attention, and more and more scholars have begun to study it. So far, there are three main methods for studying this subject: model-based, pattern-based and neural network-based. This dissertation chooses to use neural network to study the subject and improves the Autoencoder Long-term Recurrent Convolutional Networks (AE-LRCN) algorithm. The discrete Wavelet transform (DWT) algorithm is used to reduce the dimensionality of the data to obtain two coefficients which will be put into the autoencoder. Then use the Canonical Correlation Analysis (CCA) algorithm to fuse the two sets of feature vectors obtained from the autoencoder. Finally, LRCN algorithm is used to realize human behavior recognition.
The proposed algorithm further shortens the training time and improves the convergence speed of the neural network while maintaining the high accuracy of the original algorithm. According to experiments, it can be found that no matter what kind of clothes a person wears (long-sleeved and short-sleeved), it does not affect the recognition of human behavior, and the accuracy rate can reach nearly 99%.Master of Science (Signal Processing
Leveraging Smart Lights for Passive Localization
No full textLocalization based on visible light is gaining significant attention. But most existing studies rely on a key requirement: the object of interest needs to carry an optical receiver (camera or photodiode). We remove this requirement and investigate the possibility of achieving accurate localization in a passive manner, that is, without requiring objects to carry any optical receiver. To achieve this goal, we exploit the reflective surfaces of objects and the unique propagation properties of LED luminaires. We present geometric models, a testbed implementation, and empirical evaluations to showcase the opportunities and challenges posed by this new type of localization. Overall, we show that our method can track with high accuracy (few centimeters) a subset of an object’s trajectory and it can also identify passively the object’s ID.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Embedded System
Chen Weisong yu Xu Ziyun de an li
No full text每當提及中國古代男色關係時，閱史不深者 ，或未能打破「異性戀常規」的刻板印象，以為男色關係不曾存在於強調傳宗接代、褒揚孝道文化的中國傳統社會中；或習慣援引現代西方病理化同性戀的論述，將男色污名化，視之為少數人的反常嗜好。稍識其事者，能不致於偏聽權力知識所傳播的一種論述，知悉歷史上男色關係曾流行成風，卻僅憑表象，而無太多實證的情況下，論斷中國社會曾寬容對待男色關係，未察這種歸納委實過度簡單化，未能理解環繞男色所建立的關係複雜性。以本文所述的陳維崧及徐紫雲二人關係為例，即使能微觀男色關係的研究者亦多以陳維崧的文字為憑，復以情感層面的框架定位出男色關係，使其對男色關係的解讀不免流於主觀，亦欠卻對徐紫雲的主體性的關懷。本文對應上述三種對男色關係的理解，回饋三種層次的知識：知從前所未知；對往昔一知半解者，豐富其所知；對已知者，復稽其所知。前緣部份，吐露筆者建基於在地性及人文關懷的研究動機。第一章解釋以男色命名關係的原由，及在前現代──現代─後現代、西方──東方的脈絡中，略陳前人研究的語境，並綜述其研究內容。第二章則透過彙整史料，呈示明末清初的男色生態，並探討造就該現象的時代因素。第三章講述陳維崧的生平故事。第四章除整理陳、徐二人的生平和交往，更討論「異性戀常規」如何令男色關係陷於失語的狀態。並關懷二人各自的主體性，更具深度地考量這段男色關係的性質及其操作。針對今日學界的論述如「冒襄笑遣雲郎乃完成了佔有權轉移」及「好男色者皆為雙性戀者」提出質疑。第五章聚焦於《九青圖詠》，以陳維崧與題詠者的交誼為觀察窗口，對題詠內容再作解讀，透析一種鮮有學者提及的客套之情，以豐富學界對箇中題詠立意的解釋，從而對時人對男色大都抱有欣賞之意的看法作出反思。第六章總結並歸納全文要點。When it comes to the nanse relationship in ancient Chinese society, people who hardly comprehend the context of history may well judge that there was no breeding ground for such relationship since Chinese culture places much emphasis on the continuation of one’s ancestral line and attaches much importance to filial piety. Meanwhile some people may tend to perceive such homosexual relationship as an abnormal behavior for the minority on the basis of modern western discourse of pathologized homosexuality, thus turning a blind eye to this stigmatized aspect. To those who somewhat understand the past, they might be able to extend their vision beyond what has been produced by the power knowledge, and thus would realize that there were various kinds of nanse relationships among different classes. They however might merely emphasize the popularity of the phenomena and conclude that such relationship was commonly tolerated. Such oversimplified argumentation would contribute to a kind of biased comprehension in which the nature of nanse relationship can by no means be concretely captured. Even to those who conduct micro study of nanse relationship, take my case of Chen Weisong and Xu Ziyun as an example, they usually capitalize on Chen’s literary works in discussing nanse relationship in terms of emotion regardless of the limitation of such subjective interpretation. And Less attention has been paid to the issue of Xu Ziyun’s subjectivity.To remedy the above problem, this thesis is to produce three kinds of knowledge according to the aforementioned different levels of comprehension of nanse relationship, using the Chen-Xu relationship as a case to tell those without the knowledge of the history the neglected story, to inform those having half-baked knowledge, and to enrich the existing scholarship by reviewing the issue. To begin the thesis with a foreword, I declear my research motive which is related to a kind of local and humanistic concern. The first chapter explains the reasons for using nanse to name the male-male relationship in ancient Chinese society and reviews the previous studies in the Pre-Modern─Modern─Post-Modern and the West－East context. The second chapter shows the phenomenon of nanse relationship during late Ming and early Qing period and explicates its popularity. The third chapter introduces Chen Weisong’s life. The fourth chapter not only describes how Chen and Xu interacted, but also analyses how nanse relationship was misplaced owing to the operation of heteronormativity. In so doing, I provide the scholarship with an insight into Chen-Xu’s nanse relationship with emphasis on their subjectivities. In the midst of my argumentation, existing scholarly observations such as "Mao Xiang sent Ziyun to Chen to indicate the completion of shifting possession", "those immersing in Nanse are all bisexual," and so forth are challenged. The fifth chapter focuses on the picture Jiuqing tuyong and interprets the pomes on it by explicating the relationship between the poets and Chen, thus detecting a kind of civilities that existed among them. This discovery can enrich the existing scholarship concerning the poests’ objectives of writing the poems so as to respond to the question about their appreciation of nanse relationship. The sixth chapter concludes the thesis by highlighting the vital points mentioned in the previous chapters.Detailed summary in vernacular field only.Detailed summary in vernacular field only.李俊威.Thesis (M.Phil.) Chinese University of Hong Kong, 2015.Includes bibliographical references (leaves 257-273).Abstracts in English and Chinese.Li Junwei
Construction of a highly error-prone DNA polymerase for developing organelle mutation systems
No full textA novel family of DNA polymerases replicates organelle genomes in a wide distribution of taxa encompassing plants and protozoans. Making error-prone mutator versions of gamma DNA polymerases revolutionised our understanding of animal mitochondrial genomes but similar advances have not been made for the organelle DNA polymerases present in plant mitochondria and chloroplasts. We tested the fidelities of error prone tobacco organelle DNA polymerases using a novel positive selection method involving replication of the phage lambda cI repressor gene. Unlike gamma DNA polymerases, ablation of 3’-5’ exonuclease function resulted in a modest 5-8 fold error rate increase. Combining exonuclease deficiency with a polymerisation domain substitution raised the organelle DNA polymerase error rate by 140-fold relative to the wild type enzyme. This high error rate compares favourably with error-rates of mutator versions of animal gamma DNA polymerases. The error prone organelle DNA polymerase introduced mutations at multiple locations ranging from two to seven sites in half of the mutant cI genes studied. Single base substitutions predominated including frequent A:A (template: dNMP) mispairings. High error rate and semi-dominance to the wild type enzyme in vitro make the error prone organelle DNA polymerase suitable for elevating mutation rates in chloroplasts and mitochondria.<br/
Application verification research of cloud computing technology in the field of real time aerospace experiment
No full textCloud computing task scheduling strategy based on improved differential evolution algorithm
No full textCloud computing task scheduling strategy based on differential evolution and ant colony optimization
No full textDiscovery of robust in-plane ferroelectricity in atomic-thick SnTe
No full textStable ferroelectricity with high transition temperature in nanostructures is needed for miniaturizing ferroelectric devices. Here, we report the discovery of the stable in-plane spontaneous polarization in atomic-thick tin telluride (SnTe), down to a 1-unit cell (UC) limit. The ferroelectric transition temperature Tcof 1-UC SnTe film is greatly enhanced from the bulk value of 98 kelvin and reaches as high as 270 kelvin. Moreover, 2- to 4-UC SnTe films show robust ferroelectricity at room temperature.The interplay between semiconducting properties and ferroelectricity in this two-dimensional material may enable a wide range of applications in nonvolatile high-density memories, nanosensors, and electronics.United States. Department of Energy (Award DE-SC0010526
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