57 research outputs found

    Efficient Integration of Multi-Order Dynamics and Internal Dynamics in Stock Movement Prediction

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    Advances in deep neural network (DNN) architectures have enabled new prediction techniques for stock market data. Unlike other multivariate time-series data, stock markets show two unique characteristics: (i) \emph{multi-order dynamics}, as stock prices are affected by strong non-pairwise correlations (e.g., within the same industry); and (ii) \emph{internal dynamics}, as each individual stock shows some particular behaviour. Recent DNN-based methods capture multi-order dynamics using hypergraphs, but rely on the Fourier basis in the convolution, which is both inefficient and ineffective. In addition, they largely ignore internal dynamics by adopting the same model for each stock, which implies a severe information loss. In this paper, we propose a framework for stock movement prediction to overcome the above issues. Specifically, the framework includes temporal generative filters that implement a memory-based mechanism onto an LSTM network in an attempt to learn individual patterns per stock. Moreover, we employ hypergraph attentions to capture the non-pairwise correlations. Here, using the wavelet basis instead of the Fourier basis, enables us to simplify the message passing and focus on the localized convolution. Experiments with US market data over six years show that our framework outperforms state-of-the-art methods in terms of profit and stability. Our source code and data are available at \url{https://github.com/thanhtrunghuynh93/estimate}.Comment: Technical report for accepted paper at WSDM 202

    A new species of Typhonium (Araceae) from Vietnam

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    Typhonium obtusum is described as a new species endemic to Vietnam. It is unique in the genus in having an oblong-elliptic spathe limb with an obtuse apex and yellowish-greenish filiform staminodes with a down-curved acumen. The ecology, distribution and assessment of the conservation status of the new taxon, as well as a key to all known Typhonium species in Vietnam, are provided

    An efficient adaptive fuzzy hierarchical sliding mode control strategy for 6 degrees of freedom overhead crane

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    The paper proposes a new approach to efficiently control a three-dimensional overhead crane with 6 degrees of freedom (DoF). Most of the works proposing a control law for a gantry crane assume that it has five output variables, including three positions of the trolley, bridge, and pulley and two swing angles of the hoisting cable. In fact, the elasticity of the hoisting cable, which causes oscillation in the cable direction, is not fully incorporated into the model yet. Therefore, our work considers that six under-actuated outputs exist in a crane system. To design an efficient controller for the 6 DoF crane, it first employs the hierarchical sliding mode control approach, which not only guarantees stability but also minimizes the sway and oscillation of the overhead crane when it transports a payload to a desired location. Moreover, the unknown and uncertain parameters of the system caused by its actuator nonlinearity and external disturbances are adaptively estimated and inferred by utilizing the fuzzy inference rule mechanism, which results in efficient operations of the crane in real time. More importantly, stabilization of the crane controlled by the proposed algorithm is theoretically proved by the use of the Lyapunov function. The proposed control approach was implemented in a synthetic environment for the extensive evaluation, where the obtained results demonstrate its effectiveness. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

    An Aquaculture Water Checker--design and Manufacture

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    A real-time, mobile aquaculture water checker is presented. The configuration of double integrating spheres is developed for simultaneously measuring backward scattering RdR_d, forward scattering TdT_d  and transmitted light TcT_c . Based on Kubelka-Munk model, a set of optical parameters including absorption coefficient μa\mu _a , scattering coefficient μs\mu_s and anisotropy  gg  are calculated. The obtained results for diluted milk standard samples with different milk concentrations and aquaculture water samples with different densities of Psexdo-Nitzschia-delicatissium algae are also reported

    Chemical profiles and antibacterial activity of acetone extract of two Curcuma species from Vietnam

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    Curcuma thorelii Gagnep. and Curcuma cotuana Luu, Škorni?k. & H.?.Tr?n are the rare species only found in Southeast Asia. The present study was the first to explore the chemical compositions and antibacterial effects of the whole plant acetone extracts of these 2 species. Altogether 41 and 31 compounds have been identified in C. thorelii and C. cotuana extracts by gas chromatography/mass spectrometry. Accordingly, the C. thorelii extract contained (E)-labda-8(17),12-diene-15,16-dial (33.37%), vitamin E (12.33%), phytol (9.83%) as the major compounds while C. cotuana extract contained predominantly (E)-labda-8(17),12-diene-15,16-dial (14.58%), n-hexadecanoic acid (10.96%), 3,7,11,15-tetramethylhexadec-2-en-1-yl acetate (8.13%), ?-sitosterol (7.97%). In addition, results from disc diffusion assay have shown that C. thorelii acetone extract had inhibitory effects on 5 out of 10 pathogenic bacterial strains such as Bacillus cereus (ATCC 11778), Listeria monocytogenes (ATCC 19111), Staphylococcus aureus (ATCC 25923), S. aureus (ATCC 29213) and S. saprophyticus (BAA750) while C. cotuana acetone extract was found to be effective only against B. cereus. The obtained results showed that the acetone extracts of C. thorelii and C. cotuana possessed several valuable bioactive compounds as well as promising antibacterial activity, which place a good foundation for future pharmaceutical product development

    A Multi-Center Randomised Controlled Trial of Gatifloxacin versus Azithromycin for the Treatment of Uncomplicated Typhoid Fever in Children and Adults in Vietnam

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    BACKGROUND: Drug resistant typhoid fever is a major clinical problem globally. Many of the first line antibiotics, including the older generation fluoroquinolones, ciprofloxacin and ofloxacin, are failing. OBJECTIVES: We performed a randomised controlled trial to compare the efficacy and safety of gatifloxacin (10 mg/kg/day) versus azithromycin (20 mg/kg/day) as a once daily oral dose for 7 days for the treatment of uncomplicated typhoid fever in children and adults in Vietnam. METHODS: An open-label multi-centre randomised trial with pre-specified per protocol analysis and intention to treat analysis was conducted. The primary outcome was fever clearance time, the secondary outcome was overall treatment failure (clinical or microbiological failure, development of typhoid fever-related complications, relapse or faecal carriage of S. typhi). PRINCIPAL FINDINGS: We enrolled 358 children and adults with suspected typhoid fever. There was no death in the study. 287 patients had blood culture confirmed typhoid fever, 145 patients received gatifloxacin and 142 patients received azithromycin. The median FCT was 106 hours in both treatment arms (95% Confidence Interval [CI]; 94-118 hours for gatifloxacin versus 88-112 hours for azithromycin), (logrank test p = 0.984, HR [95% CI] = 1.0 [0.80-1.26]). Overall treatment failure occurred in 13/145 (9%) patients in the gatifloxacin group and 13/140 (9.3%) patients in the azithromycin group, (logrank test p = 0.854, HR [95% CI] = 0.93 [0.43-2.0]). 96% (254/263) of the Salmonella enterica serovar Typhi isolates were resistant to nalidixic acid and 58% (153/263) were multidrug resistant. CONCLUSIONS: Both antibiotics showed an excellent efficacy and safety profile. Both gatifloxacin and azithromycin can be recommended for the treatment of typhoid fever particularly in regions with high rates of multidrug and nalidixic acid resistance. The cost of a 7-day treatment course of gatifloxacin is approximately one third of the cost of azithromycin in Vietnam. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN67946944

    The Association of Cytokines with Severe Dengue in Children

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    Background: Dengue virus infection is a major public health problem. A hypothesis put forward for severe dengue is the cytokine storm, a sudden increase in cytokines that induces vascular permeability. Previous studies and our recent meta-analysis showed that IL-6, IL-8, IFNγ, TNFα, VEGF-A and VCAM-1 are associated with dengue shock syndrome. Therefore, in this study we aim to validate the association of these cytokines with severe dengue. Methods & Findings: In a hospital based-case control study in Vietnam, children with dengue fever, other febrile illness and healthy controls were recruited. Dengue virus infection was confirmed by several diagnostic tests. Multiplex immunoassay using Luminex technology was used to measure cytokines simultaneously. A positive association with dengue shock syndrome was found for VCAM-1, whereas a negative association was found for IFNγ. Furthermore, multivariate logistic analysis also showed that VCAM-1 and IFNγ were independently correlated with dengue shock syndrome. Conclusion: IFNγ and VCAM-1 were associated with dengue shock syndrome, although their role in the severe dengue pathogenesis remains unclear. Additional studies are required to shed further light on the function of these cytokines in severe dengue

    Prospects for Food Fermentation in South-East Asia, Topics From the Tropical Fermentation and Biotechnology Network at the End of the AsiFood Erasmus+Project

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    Fermentation has been used for centuries to produce food in South-East Asia and some foods of this region are famous in the whole world. However, in the twenty first century, issues like food safety and quality must be addressed in a world changing from local business to globalization. In Western countries, the answer to these questions has been made through hygienisation, generalization of the use of starters, specialization of agriculture and use of long-distance transportation. This may have resulted in a loss in the taste and typicity of the products, in an extensive use of antibiotics and other chemicals and eventually, in a loss in the confidence of consumers to the products. The challenges awaiting fermentation in South-East Asia are thus to improve safety and quality in a sustainable system producing tasty and typical fermented products and valorising by-products. At the end of the “AsiFood Erasmus+ project” (www.asifood.org), the goal of this paper is to present and discuss these challenges as addressed by the Tropical Fermentation Network, a group of researchers from universities, research centers and companies in Asia and Europe. This paper presents current actions and prospects on hygienic, environmental, sensorial and nutritional qualities of traditional fermented food including screening of functional bacteria and starters, food safety strategies, research for new antimicrobial compounds, development of more sustainable fermentations and valorisation of by-products. A specificity of this network is also the multidisciplinary approach dealing with microbiology, food, chemical, sensorial, and genetic analyses, biotechnology, food supply chain, consumers and ethnology

    Application of DPSIR framework to access environmental impact of white limestone mining and processing in Luc Yen, Yen Bai province

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    Application of DPSIR framework (Drivers, Pressures, States, Impacts and Responses) aims to assess the current impact of the environment through a process starting with “driving forces” through “pressures” to “states” and “impacts” eventually leading to political “responses” in mineral mining in Luc Yen district. Research results show that the main drivers in Luc Yen are resources consumption (Wi = 3.675), the demand for industrial development (Wi = 3.575), followed by diversification and size of mines (Wi = 3.250). The environmental pressures are solid (Wi = 4.025), dust (Wi = 3.900) and wastewater (Wi = 3.625). The current state of environment is the most affected by air (Wi = 3.400). The soil and water are almost unaffected. The current environmental impacts have positive and negative social, economic and environmental impacts. Specifically, the positive impacts are employment opportunities, income (Wi = 3.325) and an increase in state budget (Wi =3.000). There are no positive improvements of the environment related to mining activities, such as negative impacts on ecological landscape (Wi = 3.050) and infrastructure (Wi = 3.075). Improving environmental quality and mitigating environmental impacts have been applied, including innovative technology (Wi = 3.175), pollution monitoring and environmental quality monitoring (Wi = 3.400). Communication activities to enhance community participation in Luc Yen area were also highly appreciated by people (Wi = 3.375).Việc ứng dụng mô hình DPSIR (Drivers, Pressures, States, Impacts and Responses) nhằm mục đích đánh giá tác động môi trường theo một quá trình từ động lực, áp lực, hiện trạng và tác động đến đáp ứng để giải quyết vấn đề môi trường liên quan đến hoạt động khai thác khoáng sản tại huyện Lục Yên. Kết quả nghiên cứu cho thấy động lực dẫn tới hoạt động khai thác đá vôi trắng tại huyện Lục Yên là nhu cầu sử dụng tài nguyên (Wi = 3,675), nhu cầu phát triển hoạt động công nghiệp (Wi = 3,575), tiếp đến là sự đa dạng, quy mô các mỏ khoáng (Wi = 3,250). Áp lực môi trường là chất thải rắn (Wi = 4,025), tiếp đến là bụi (Wi = 3,900) và nước thải (Wi = 3,625). Hiện trạng môi trường tự nhiên hiện nay tại khu vực Lục Yên chịu ảnh hưởng mạnh nhất là không khí (trọng số Wi = 3,400), môi trường đất và nước gần như chưa bị tác động. Tác động môi trường hiện nay tại huyện Lục Yên thể hiện qua tác động đến môi trường xã hội và môi trường tự nhiên. Cụ thể, tác động giải quyết việc làm, tăng thu nhập (Wi = 3,325) và tăng ngân sách nhà nước (Wi = 3,000). Tác động tiêu cực tới cảnh quan sinh thái (Wi = 3,050) và cơ sở hạ tầng (Wi = 3,075). Các giải pháp cải thiện và giảm thiểu tác động môi trường đã áp dụng hiện nay là đổi mới công nghệ khai thác theo hướng tiên tiến (Wi = 3,175), giám sát ô nhiễm và quan trắc chất lượng môi trường (Wi = 3,400). Giải pháp truyền thông tăng cường sự tham gia của cộng đồng tại khu vực Lục Yên cũng được người dân đánh giá cao với trọng số (Wi = 3,375)
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