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Cyclohexanol is a commonly used organic compound. Currently, the most promising industrial process for synthesizing cyclohexanol, by cyclohexene hydration, suffers from a low conversion rate and difficult separation. In this paper, a three-column process for catalytic distillation applicable in the hydration of cyclohexene to cyclohexanol was established to solve these. Simulation with Aspen plus shows that the process has good advantages, the conversion of cyclohexene reached 99.3%, and the product purity was ≥99.2%. The stable operation of the distillation system requires a good control scheme. The design of the control scheme is very important. However, at present, the reactive distillation process for cyclohexene hydration is under investigation experimentally and by steady-state simulation. Therefore, three different plant-wide control schemes were established (CS1, CS2, CS3). and the position of temperature sensitive stage was selected by using sensitivity analysis method and singular value decomposition method. The Tyreus-Luyben empirical tuning method was used to tune the controller parameters. Finally, Aspen Dynamics simulation software was used to evaluate the performance of the three control schemes. By introducing ΔF±20% and xENE±5%), comparison the changes in product purity and yield of the three different control schemes. By comparison, we can see that the control scheme CS3 has the best performance.

Background The beneficial effects of ω−3 polyunsaturated fatty acids (PUFA) vary between different sources. However, there is a paucity of comparative studies regarding the effects and mechanisms of marine and plant ω−3 PUFA on obesity. Objective The aim of this study was to evaluate the effects of fish oil (FO) and perilla oil (PO) on glucolipid metabolism, inflammation, and adipokine in mice fed a high-fat (HF) diet in association with the contribution of toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88) pathway. Methods C57BL/6J mice and MyD88−/− mice were randomly divided into 4 groups: normal chow diet, HF diet, HF diet accompanied by daily gavage with either FO or PO. After 4 weeks, blood biochemistries, adipocyte histology, mRNA, and protein expression of MyD88-dependent and -independent pathways of TLR4 signaling in epididymal adipose tissue were measured. Results In C57BL/6J mice, there were no statistical differences between FO and PO in decreasing body weight, glucose, insulin, triglyceride, total cholesterol, interleukin-6, and increasing adipocyte counts. FO and PO decreased mRNA and protein expression of TLR4, MyD88, tumor necrosis factor receptor-associated factor 6, inhibitor of nuclear factor kappa B kinase beta and nuclear factor-kappa B p65. In MyD88−/− mice, the beneficial effects of FO and PO on HF diet-induced metabolism abnormalities and inflammation were abolished. FO and PO had no impacts on mRNA and protein expression of receptor-interacting protein-1, interferon regulate factor 3, and nuclear factor-kappa B p65. Conclusion FO and PO exhibit similar protective effects on metabolic disorders and inflammation through inhibiting TLR4 signaling in a manner dependent on MyD88. These findings highlight plant ω−3 PUFA as an attractive alternative source of marine ω−3 PUFA and reveal a mechanistic insight for preventive benefits of ω−3 PUFA in obesity and related metabolic diseases.

The traditional logistics vehicle tracking method lacks the function of active identification and switch tracking. Therefore, in the presence of interference, there are some problems such as interf...

There is a Chinese proverb, “if your wine tastes really good, you do not need to worry about the location of your bar (酒香不怕巷子深)”, which implies that the popular places for local residents are sometimes hidden behind an unassuming door or on unexpected streets. Discovering these unassuming places (e.g. restaurants) of a city will benefit the understanding of local culture and help to build livable neighborhoods. Previous work has been limited by the lack of appropriate data sources and efficient tools to evaluate the popularity, ambiance and physical surroundings of places in large-scale urban areas. In addition, how to characterize places with respect to different groups of people remains unclear. In this work, we propose a data-driven approach using social media check-ins and street-level images to compare the different activity patterns of visitors and locals, and uncover inconspicuous but interesting places for them in a city. We use check-in records as a proxy of the popularity of a particular type of place, and differentiate visitors and locals based on their travel and social media behaviors. In addition, we employ street-level images to represent the physical environments of places. As a result, we discovered a number of inconspicuous yet popular restaurants in Beijing. These restaurants are located mostly in deep alleys of Old Beijing neighborhoods, where the physical environments are not particularly appealing; however, these places are frequently visited by locals for social engagements. We also discovered beautiful but unpopular outdoor places in Beijing. These places are potential recreational areas for all groups of people and could be improved regarding urban design and planning to make these public infrastructures more attractive. This work demonstrates how multi-source big geo-data can be combined to build comprehensive place-based representations for different groups of people.

Virtual Geographic Environment Cognition is the attempt to understand the human cognition of surface features, geographic processes, and human behaviour, as well as their relationships in the real world. From the perspective of human cognition behaviour analysis and simulation, previous work in Virtual Geographic Environments (VGEs) has focused mostly on representing and simulating the real world to create an ‘interpretive’ virtual world and improve an individual’s active cognition. In terms of reactive cognition, building a user ‘evaluative’ environment in a complex virtual experiment is a necessary yet challenging task. This paper discusses the outlook of VGEs and proposes a framework for virtual cognitive experiments. The framework not only employs immersive virtual environment technology to create a realistic virtual world but also involves a responsive mechanism to record the user’s cognitive activities during the experiment. Based on the framework, this paper presents two potential implementation methods: first, training a deep learning model with several hundred thousand street view images scored by online volunteers, with further analysis of which visual factors produce a sense of safety for the individual, and second, creating an immersive virtual environment and Electroencephalogram (EEG)-based experimental paradigm to both record and analyse the brain activity of a user and explore what type of virtual environment is more suitable and comfortable. Finally, we present some preliminary findings based on the first method.

With the two cores of database and model-base, Virtual Geographic Environment (VGE) breaks the limitations of the traditional Geographic Information System (GIS), which provides new support to the study and understanding of our world. [...]

The author in this research attempts to illustrate a measurable relationship between the physical environment and human’s visual perception, including the distance, visual angle impact and visual field (a 3D isovist conception) against human's cognition way, by using a 3D visibility analysis method based on the platform of Virtual Geographic Environment (VGE). The whole project carries out in the CUHK campus (the Chinese University of Hong Kong), by adopting a virtual 3D model of the whole campus and survey in real world. A possible model for the simulation of human cognition in urban spaces is expected to be the output of this research, such as what the human perceive from the environment, how their feelings and behaviours are and how they affect the surrounding world. Kevin Lynch raised 5 elements of urban design in 1960s, which are "vitality, sense, fit, access and control". As the development of urban design, several problems around the human's cognitive and behaviour have come out. Due to the restriction of sensing knowledge in urban spaces, the research among the "sense" and the "fit" of urban design were not quite concerned in recent decades. The geo-spatial cognition field comes into being in 1997 and developed in recent 15 years, which made great effort in way-finding and urban behaviour simulation based on the platform of GIS (geographic information system) or VGE. The platform of VGE is recognized as a proper tool for the analysis of human's perception in urban places, because of its efficient 3D spatial data management and excellent 3D visualization for output result. This article will generally describe the visibility analysis method based on the 3D VGE platform. According to the uncertainty and variety of human perception existed in this research, the author attempts to arrange a survey of observer investigation and validation for the analysis results. Four figures related with space and human’s perception will be mainly concerned in this proposal: openness, permeability, environmental pressure and visibility, and these will also be used as the identification for different type of spaces. Generally, the author is aiming at contributing a possible way to understand the reason of human’s cognition in geo-spatial area, and provides efficient mathematical model between spatial information and visual perception to the related research field.

Scope The aim of this study is to examine whether perilla oil supplementation improves glucolipid metabolism and modulates gut microbiota in diabetic KKAy mice. Methods and results The successfully established diabetic KKAy mice are randomized into four groups: diabetic model (DM), low-dose perilla oil (LPO), middle-dose perilla oil (MPO), and high-dose perilla oil (HPO). C57BL/6J mice are fed a chow diet as normal control (NC). At the end of 12 weeks, mice are euthanized and glucolipid indications are analyzed. Gut microbiota analysis is carried out based on the sequencing results on V4 region of 16S rRNA. Although serum glucose, insulin, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, abundance-based coverage estimator, and shannon are unchanged, serum triglyceride significantly decreases in LPO compared with DM. The histopathological changes of hepatocellular macrovesicular steatosis and adipocyte hypertrophy are ameliorated by perilla oil supplementation. Blautia is significantly decreased in LPO, MPO, and HPO, compared with DM. Nonmetric multidimensional scaling analysis shows NC and LPO are relatively coherent. Conclusion These findings indicate that dietary supplementation with perilla oil can improve hypertriglyceridemia and gut dysbiosis in diabetic KKAy mice, which can be associated with potential benefits to human health.

Most simulation-based noise maps are important for official noise assessment but lack local noise characteristics. The main reasons for this lack of information are that official noise simulations only provide information about expected noise levels, which is limited by the use of large-scale monitoring of noise sources, and are updated infrequently. With the emergence of smart cities and ubiquitous sensing, the possible improvements enabled by sensing technologies provide the possibility to resolve this problem. This study proposed an integrated methodology to propel participatory sensing from its current random and distributed sampling origins to professional noise simulation. The aims of this study were to effectively organize the participatory noise data, to dynamically refine the granularity of the noise features on road segments (e.g., different portions of a road segment), and then to provide a reasonable spatio-temporal data foundation to support noise simulations, which can be of help to researchers in understanding how participatory sensing can play a role in smart cities. This study first discusses the potential limitations of the current participatory sensing and simulation-based official noise maps. Next, we explain how participatory noise data can contribute to a simulation-based noise map by providing (1) spatial matching of the participatory noise data to the virtual partitions at a more microscopic level of road networks, (2) multi-temporal scale noise estimations at the spatial level of virtual partitions, and (3) dynamic aggregation of virtual partitions by comparing the noise values at the relevant temporal scale to form a dynamic segmentation of each road segment to support multiple spatio-temporal noise simulations. In this case study, we demonstrate how this method could play a significant role in a simulation-based noise map. Together, these results demonstrate the potential benefits of participatory noise data as dynamic input sources for noise simulations on multiple spatio-temporal scales.

Geographic information system (GIS) professionals recognize that geographic process is essential for understanding what is happening in the world, learning how the environment is changing, modelling how complex systems work and giving context to other types of data. Consequently, geographic process models have been increasingly featured for the next generation geographic information science (system), as a method for phenomena simulation and mechanism analysis of the physical environment and its live activities, thereby driving conventional GIS based on data manipulation into the world of dynamic and computational processes (Goodchild, 2006; Yuan and Hornsby, 2008; Torrens, 2009; CSDGS et al., 2010).

The rapid development of World Wide Web and the dominance of networked computers for information transfer and communication have enabled the rise of virtual worlds (e.g. Second Life™). This paper introduces our virtual campus-Virtual CUHK (VCUHK) project which builds a 3D virtual campus of the Chinese University of Hong Kong (CUHK) in networked virtual worlds. VCUHK is a 3D shared networked virtual world of the real campus of CUHK built with Open Simulator platform, an open source virtual world server project that has an adaptation of the basic server functionality of the Second Life™ servers. The real CUHK campus occupies approximately the area of 2 square km with hilly terrain and diverse and unique landscape, and has a great number of buildings with very sophisticated architecture. By using Second Life™ viewer (an open source 3D virtual world viewer) or other compatible viewers, users can access VCUHK from any Internet-connected personal computer running MS windows or Linux. Users can immerse in VCUHK being anything with the form of 3D modeling avatar and experience virtual education and other diverse campus activities.

The development of hardware and software is not sufficient to meet the real-time visualization requirements of large scale 3D City Models. How to adaptively coordinate the speed and quality of rendering according to the data volume and hardware/software environment is therefore a critical issue. This paper proposes an algorithm which predicts the rendering time according to the features of 3D City Models at first, and then to calculate the object importance value based on the mathematical model which considers the indicators of each object: location, distance, visibility and semantics, and finally to select the object set to be rendered by a fast recursive algorithm. There are five factors selected to test their influence on rendering time: triangle number, vertex number, texture number, screen pixel number, and the texture image size. According to multivariate statistical theory, experimental results prove that both geometry and texture data size are significant for rendering time of 3D City Models. A typical 3D building group models are employed for experimental analysis. The results show that the method introduced in this paper is accurate to predict the time of rendering 3D models with detailed texture. The adaptive rendering performance is also significantly improved.

Based on the scheme of chirped pulse amplification, a Ti:sapphire laser facility with output power of 0.89 PW has been developed. The compressed pulse width of ~29.0 fs was achieved by minimizing the dispersion introduced by the optical components. The effective suppression of parasitic lasing ensured the high-gain amplification in large aperture amplifiers.