• Title/Summary/Keyword: Macau

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Preparative separation of minor saponins from Panax notoginseng leaves using biotransformation, macroporous resins, and preparative high-performance liquid chromatography

  • Liu, Fang;Ma, Ni;Xia, Fang-Bo;Li, Peng;He, Chengwei;Wu, Zhenqiang;Wan, Jian-Bo
    • Journal of Ginseng Research
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    • v.43 no.1
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    • pp.105-115
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    • 2019
  • Background: Ginsenosides with less sugar moieties may exhibit the better adsorptive capacity and more pharmacological activities. Methods: An efficient method for the separation of four minor saponins, including gypenoside XVII, notoginsenoside Fe, ginsenoside Rd2, and notoginsenoside Fd, from Panax notoginseng leaves (PNL) was established using biotransformation, macroporous resins, and subsequent preparative high-performance liquid chromatography. Results: The dried PNL powder was immersed in the distilled water at $50^{\circ}C$ for 30 min for converting the major saponins, ginsenosides Rb1, Rc, Rb2, and Rb3, to minor saponins, gypenoside XVII, notoginsenoside Fe, ginsenoside Rd2, and notoginsenoside Fd, respectively, by the enzymes present in PNL. The adsorption characteristics of these minor saponins on five types of macroporous resins, D-101, DA-201, DM-301, X-5, and S-8, were evaluated and compared. Among them, D-101 was selected due to the best adsorption and desorption properties. Under the optimized conditions, the fraction containing the four target saponins was separated by D-101 resin. Subsequently, the target minor saponins were individually separated and purified by preparative high-performance liquid chromatography with a reversed-phase column. Conclusion: Our study provides a simple and efficient method for the preparation of these four minor saponins from PNL, which will be potential for industrial applications.

Probabilistic real-time updating for geotechnical properties evaluation

  • Ng, Iok-Tong;Yuen, Ka-Veng;Dong, Le
    • Structural Engineering and Mechanics
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    • v.54 no.2
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    • pp.363-378
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    • 2015
  • Estimation of geotechnical properties is an essential but challenging task since they are major components governing the safety and reliability of the entire structural system. However, due to time and budget constraints, reliable geotechnical properties estimation using traditional site characterization approach is difficult. In view of this, an alternative efficient and cost effective approach to address the overall uncertainty is necessary to facilitate an economical, safe and reliable geotechnical design. In this paper a probabilistic approach is proposed for real-time updating by incorporating new geotechnical information from the underlying project site. The updated model obtained from the proposed method is advantageous because it incorporates information from both existing database and the site of concern. An application using real data from a site in Hong Kong will be presented to demonstrate the proposed method.

Conceptualizing Accessible Tourism with Smart Technologies

  • Lin, Katsy Jiaxin;Ye, Huiyue;Law, Rob
    • Journal of Smart Tourism
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    • v.2 no.2
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    • pp.5-14
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    • 2022
  • In recent years, UNWTO and academics have called for the development of responsible, sustainable, and universally accessible tourism to promote equal human rights and social inclusion. Prior studies have also revealed the potential and value of smart technologies in reducing, if not removing, barriers to people with access requirements during travel and in their everyday lives. However, a guiding framework of how smart technologies assist in building an accessible destination is still absent, thereby hindering the progress of building accessible tourism. This paper aims to fill this knowledge gap. A conceptual model of smart accessible destination (SAD) was proposed drawing from the intersection of accessible tourism and smart tourism. With the guidance of this conceptual model, tourism destinations and stakeholders can recognize and utilize the synergies of accessible and smart tourism to enhance the social inclusion, competitiveness, and sustainability of a destination.

Dynamic Modeling and Adaptive Neural-Fuzzy Control for Nonholonomic Mobile Manipulators Moving on a Slope

  • Liu Yugang;Li Yangmin
    • International Journal of Control, Automation, and Systems
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    • v.4 no.2
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    • pp.197-203
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    • 2006
  • This paper addresses dynamic modeling and task-space trajectory following issues for nonholonomic mobile manipulators moving on a slope. An integrated dynamic modeling method is proposed considering nonholonomic constraints and interactive motions. An adaptive neural-fuzzy controller is presented for end-effector trajectory following, which does not rely on precise apriori knowledge of dynamic parameters and can suppress bounded external disturbances. Effectiveness of the proposed algorithm is verified through simulations.

Online estimation of noise parameters for Kalman filter

  • Yuen, Ka-Veng;Liang, Peng-Fei;Kuok, Sin-Chi
    • Structural Engineering and Mechanics
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    • v.47 no.3
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    • pp.361-381
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    • 2013
  • A Bayesian probabilistic method is proposed for online estimation of the process noise and measurement noise parameters for Kalman filter. Kalman filter is a well-known recursive algorithm for state estimation of dynamical systems. In this algorithm, it is required to prescribe the covariance matrices of the process noise and measurement noise. However, inappropriate choice of these covariance matrices substantially deteriorates the performance of the Kalman filter. In this paper, a probabilistic method is proposed for online estimation of the noise parameters which govern the noise covariance matrices. The proposed Bayesian method not only estimates the optimal noise parameters but also quantifies the associated estimation uncertainty in an online manner. By utilizing the estimated noise parameters, reliable state estimation can be accomplished. Moreover, the proposed method does not assume any stationarity condition of the process noise and/or measurement noise. By removing the stationarity constraint, the proposed method enhances the applicability of the state estimation algorithm for nonstationary circumstances generally encountered in practice. To illustrate the efficacy and efficiency of the proposed method, examples using a fifty-story building with different stationarity scenarios of the process noise and measurement noise are presented.

Video-Induced Visit to a Destination: The Psychological Mechanism and the Role of Video Sharing Sources

  • Wang, Erin Yirun;Luo, Sara Yushan;Fong, Lawrence Hoc Nang;Law, Rob
    • Journal of Smart Tourism
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    • v.1 no.3
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    • pp.7-16
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    • 2021
  • Promotional videos have been increasingly adopted in social media marketing. Given that video production incurs high costs, evaluating the effectiveness of promotional videos is necessary. This research examines the effect of promotional video on visit intention through affective and cognitive destination images, respectively. Furthermore, grounded in the theoretical reasoning of social ties and persuasive intent, the effects of promotional videos disseminated by different sources (i.e., unknown users, friends, and marketers) are compared. Two experimental studies were carried out with 200 participants in Study 1 and 243 participants in Study 2. Study 1 revealed that the presence of promotional video induces visit intention through affective and cognitive destination images. Study 2 found that promotional videos disseminated by friends (versus unknown users) are more effective to induce visit intention because of positive cognitive destination image, while the video effects are indifferent between marketers and users. Meaningful implications are provided for destination marketers.

Wireless sensor network design for large-scale infrastructures health monitoring with optimal information-lifespan tradeoff

  • Xiao-Han, Hao;Sin-Chi, Kuok;Ka-Veng, Yuen
    • Smart Structures and Systems
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    • v.30 no.6
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    • pp.583-599
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    • 2022
  • In this paper, a multi-objective wireless sensor network configuration optimization method is proposed. The proposed method aims to determine the optimal information and lifespan wireless sensor network for structural health monitoring of large-scale infrastructures. In particular, cluster-based wireless sensor networks with multi-type of sensors are considered. To optimize the lifetime of the wireless sensor network, a cluster-based network optimization algorithm that optimizes the arrangement of cluster heads and base station is developed. On the other hand, based on the Bayesian inference, the uncertainty of the estimated parameters can be quantified. The coefficient of variance of the estimated parameters can be obtained, which is utilized as a holistic measure to evaluate the estimation accuracy of sensor configurations with multi-type of sensors. The proposed method provides the optimal wireless sensor network configuration that satisfies the required estimation accuracy with the longest lifetime. The proposed method is illustrated by designing the optimal wireless sensor network configuration of a cable-stayed bridge and a space truss.

Converting Panax ginseng DNA and chemical fingerprints into two-dimensional barcode

  • Cai, Yong;Li, Peng;Li, Xi-Wen;Zhao, Jing;Chen, Hai;Yang, Qing;Hu, Hao
    • Journal of Ginseng Research
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    • v.41 no.3
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    • pp.339-346
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    • 2017
  • Background: In this study, we investigated how to convert the Panax ginseng DNA sequence code and chemical fingerprints into a two-dimensional code. In order to improve the compression efficiency, GATC2Bytes and digital merger compression algorithms are proposed. Methods: HPLC chemical fingerprint data of 10 groups of P. ginseng from Northeast China and the internal transcribed spacer 2 (ITS2) sequence code as the DNA sequence code were ready for conversion. In order to convert such data into a two-dimensional code, the following six steps were performed: First, the chemical fingerprint characteristic data sets were obtained through the inflection filtering algorithm. Second, precompression processing of such data sets is undertaken. Third, precompression processing was undertaken with the P. ginseng DNA (ITS2) sequence codes. Fourth, the precompressed chemical fingerprint data and the DNA (ITS2) sequence code were combined in accordance with the set data format. Such combined data can be compressed by Zlib, an open source data compression algorithm. Finally, the compressed data generated a two-dimensional code called a quick response code (QR code). Results: Through the abovementioned converting process, it can be found that the number of bytes needed for storing P. ginseng chemical fingerprints and its DNA (ITS2) sequence code can be greatly reduced. After GTCA2Bytes algorithm processing, the ITS2 compression rate reaches 75% and the chemical fingerprint compression rate exceeds 99.65% via filtration and digital merger compression algorithm processing. Therefore, the overall compression ratio even exceeds 99.36%. The capacity of the formed QR code is around 0.5k, which can easily and successfully be read and identified by any smartphone. Conclusion: P. ginseng chemical fingerprints and its DNA (ITS2) sequence code can form a QR code after data processing, and therefore the QR code can be a perfect carrier of the authenticity and quality of P. ginseng information. This study provides a theoretical basis for the development of a quality traceability system of traditional Chinese medicine based on a two-dimensional code.

A NUMERICAL INVESTIGATION OF INDOOR AIR QUALITY WITH CFD

  • Sin Vai Kuong;Sun Ho I
    • Journal of computational fluids engineering
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    • v.10 no.1
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    • pp.87-93
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    • 2005
  • Macao, a city with three sides bounded by water, is hot and humid in weather in more than six months of a year. This uncomfortable weather induces the frequency of operating air-conditioners. Choice of location for installation of air-conditioner in a building will affect the performance of cooling effect and thermal comfort on the occupants, which in turn will affect the indoor air quality (IAQ) of the building. In the paper, investigation of distribution on carbon dioxide, room air temperature and velocity, as well as air diffusion performance index (ADPI) of a single bedroom in Macao is studied by using the computational fluid dynamics (CFD) software FLOVENT 3.2. Simulations of locating the air-conditioner at 4 different walls will be done and comparisons and analyses of the results will be performed to decide a proper location for the air-conditioner for obtaining good thermal comfort.