90 research outputs found

    Choice of sewage sludge thermochemical disposal methods from multi‐ perspective analysis

    Get PDF
    Thermochemical conversion disposal methods for sewage sludge usually include incineration, gasification and pyrolysis. Incineration technology is relatively mature and the incineration ash can be potentially used for phosphorus (P) recovery. Gasification can be used to recover syngas which is convenient to be used for power & heat generation. While through pyrolysis, syngas of high quality, tar and char can be recovered. To make a proper choice from them, these techniques are compared from perspective of technology maturity, investment, operation cost, environmental impact and acceptability of the public. Technology maturity is evaluated by comparing industrial applications. Investment and operation cost are evaluated based on practical operation experiences; environmental impacts are evaluated based on life cycle assessment; and acceptability of the public is based on a questionnaire survey. Based on a scenario with capacity of 100 t/d in eastern China, investment are comparable for the three technologies within the range of 250,000-400,000 RMB yuan/(ton.d) with gasification close to the higher side; the operation cost varies in the range of 140 - 400 RMB yuan/ton with incineration the highest; pyrolysis corresponds to the lowest environmental impacts and the highest acceptability of the public, however the pyrolysis technology is not fully developed, especially the durable pyrolysis reactor and the application of pyrolysis char

    Research Progress on the Relevance between Intestinal Flora and Colorectal Cancer

    Get PDF
    Cancer is a common chronic disease all over the world, which will cause serious health burden. At present, the debate about the role of intestinal flora in the prevention and control of cancer has always existed. Therefore, researchers should pay close attention to the impact of intestinal flora on several cancers (such as colon cancer, liver cancer and breast cancer). In addition, it is reported that intestinal flora may also affect the efficacy of cancer chemotherapy and immunotherapy. This paper introduces some energy research results to help clear the relationship between intestinal flora and cancer, even cancer micro environment. It can help clarify the mist of cancer and gut microbiota, let those little creatures to serve the progress of improving mankind living condition and of health and medicine

    Towards efficient photoinduced charge separation in carbon nanodots and TiO 2

    Get PDF
    In this work, photoinduced charge separation behaviors in non-long-chain-molecule-functionalized carbon nanodots (CDs) with visible intrinsic absorption (CDs-V) and TiO2 composites were investigated. Efficient photoinduced electron injection from CDs-V to TiO2 with a rate of 8.8 × 108 s−1 and efficiency of 91% was achieved in the CDs-V/TiO2 composites. The CDs-V/TiO2 composites exhibited excellent photocatalytic activity under visible light irradiation, superior to pure TiO2 and the CDs with the main absorption band in the ultraviolet region and TiO2 composites, which indicated that visible photoinduced electrons and holes in such CDs-V/TiO2 composites could be effectively separated. The incident photon-to-current conversion efficiency (IPCE) results for the CD-sensitized TiO2 solar cells also agreed with efficient photoinduced charge separation between CDs-V and the TiO2 electrode in the visible range. These results demonstrate that non-long-chain-molecule-functionlized CDs with a visible intrinsic absorption band could be appropriate candidates for photosensitizers and offer a new possibility for the development of a well performing CD-based photovoltaic system

    Regional Business Environment, Agricultural Opening-Up and High-Quality Development: Dynamic Empirical Analysis from China’s Agriculture

    No full text
    Agriculture is the foundation of every country’s survival and development. This paper analyzes the interaction between the business environment, agricultural opening-up and high-quality agricultural economy from the perspective of China’s provinces. According to the panel data of 31 provinces and municipalities in China from 2009 to 2019, the empirical analysis was carried out based on the panel vector autoregression (PVAR) model. The results show that there is a quantitative interaction between China’s business environment, agricultural opening-up and high-quality agricultural development, and the long-term time effect is very obvious. Specifically, (1) the impact of the business environment and the high-quality development of agriculture on itself is decreasing year by year. The agriculture opening-up itself has a strong impact and has always maintained strong stability. (2) The high-quality development of the agricultural economy has little impact on the business environment and the opening of agriculture to the outside world, but it has a certain stable and continuous effect. It is particularly important that the agricultural opening-up has an increasingly strong effect on the business environment and the high-quality development of the agricultural economy as time progresses. Therefore, we must always adhere to the agriculture opening-up. The regional business environment and the agriculture opening-up can jointly promote the high-quality development of the agricultural economy. The research results can provide a basis and reference for the central and local governments to formulate relevant agricultural development policies and provide a reference for relevant agricultural economic entities and enterprises

    Analiza niezawodności strategii sterowania w oparciu o kilka obserwatorów stanu rozszerzonego ESO i jej zastosowanie w systemie kontroli regulacji poziomu czworonożnego robota w warunkach zakłóceń i uszkodzeń

    No full text
    The complexity of control algorithms and their vulnerability to disturbances and failures are the main problems that restrict the operations of multi-legged mobile robots in more complex environments. In this paper, a multiple extended state observer (ESO) based control strategy is proposed to achieve stable tilt angle control for quadruped robots under the influence of disturbances and actuator failures. By treating the multiple legs as parallel control objects, more ESOs were added to improve the disturbance rejection ability of the linear active disturbance rejection control (LADRC). Correlation of interactive information about the legs is realized by the synthesis of multiple ESO information. Based on LADRC, this method has the advantages of easy parameter tuning, good robustness, and strong ability to cope with interference and fault conditions. A control system reliability evaluation method was proposed. The reliability and control performance of the multi-ESO based control system under leg stuck failure conditions were systematically analyzed. Simulation and experimental results for the level adjustment control system of a quadruped robot are provided to verify the disturbance rejection ability, feasibility and practicability of the proposed multi-ESO based control method.Złożoność algorytmów sterowania oraz ich brak odporności na zakłócenia i uszkodzenia to główne czynniki ograniczające pracę wielonożnych robotów mobilnych w bardziej złożonych środowiskach. W przedstawionym artykule zaproponowano strategię sterowania wykorzystującą kilka obserwatorów stanu rozszerzonego (ESO), która pozwala na uzyskanie stabilnego kąta pochylenia robota czworonożnego w warunkach zakłóceń i uszkodzeń siłowników. Traktując każdą z nóg jako równorzędny obiekt sterowania, dodano dodatkowe ESO, co pozwoliło na poprawienie zdolności algorytmu liniowego aktywnego tłumienia zakłóceń (LADRC) do kompensacji (tłumienia) tych ostatnich. Interaktywne informacje dotyczące poszczególnych nóg korelowano poprzez syntezę danych z ESO. Zaletami omawianej metody opartej na LADRC są: łatwość dostrajania parametrów, wysoka niezawodność oraz bardzo dobra zdolność do radzenia sobie z zakłóceniami i uszkodzeniami. Zaproponowano także metodę oceny niezawodności systemu sterowania. Analizowano niezawodność i wydajność systemu opartego na kilku ESO w warunkach awarii wywołanej zablokowaniem nóg robota. Przedstawiono wyniki badań symulacyjnych i eksperymentalnych systemu sterowania regulacją poziomu robota czworonożnego, które pozwalają zweryfikować zdolność proponowanej metody do tłumienia zakłóceń, a także możliwość jej praktycznego zastosowania

    Nowatorska metoda oceny niezawodności systemów wielostanowych w oparciu o algorytm uczenia struktury

    No full text
    Traditional reliability models, such as fault tree analysis (FTA) and reliability block diagram (RBD), are typically constructed with reference to the function principle graph that is produced by system engineers, which requires substantial time and effort. In addition, the quality and correctness of the models depend on the ability and experience of the engineers and the models are difficult to verify. With the development of data acquisition, data mining and system modeling techniques, the operational data of a complex system considering multi-state, dependent behavior can be obtained and analyzed automatically. In this paper, we present a method that is based on the K2 algorithm for establishing a Bayesian network (BN) for estimating the reliability of a multi-state system with dependent behavior. Facilitated by BN tools, the reliability modeling and the reliability estimation can be conducted automatically. An illustrative example is used to demonstrate the performance of the method.Tradycyjne modele niezawodności, takie jak analiza drzewa błędów (FTA) czy schemat blokowy niezawodności (RBD), buduje się zazwyczaj w oparciu o tworzone przez inżynierów systemowych schematy zasad działania systemu, których przygotowanie wymaga dużych nakładów czasu i pracy. Jakość i poprawność tych modeli zależy od umiejętności i doświadczenia inżynierów, a same modele są trudne do zweryfikowania. Dzięki rozwojowi technik akwizycji i eksploracji danych oraz modelowania systemów, dane operacyjne złożonego systemu uwzględniające jego zależne, wielostanowe zachowania mogą być pozyskiwane i analizowane automatycznie. W artykule przedstawiono metodę konstrukcji sieci bayesowskiej (BN) opartą na algorytmie K2, która pozwala na ocenę niezawodności systemu wielostanowego o zachowaniach zależnych. Dzięki narzędziom BN, modelowanie i szacowanie niezawodności może odbywać się automatycznie. Działanie omawianej metody zilustrowano na podstawie przykładu

    An Alternative Lifetime Model for White Light Emitting Diodes under Thermal–Electrical Stresses

    No full text
    The lifetime prediction using accelerated degradation test (ADT) method has become a main issue for white light emitting diodes applications. This paper proposes a novel lifetime model for light emitting diodes (LEDs) under thermal and electrical stresses, where the junction temperature and driving current are deemed the input parameters for lifetime prediction. The features of LEDs’ lifetime and the law of lumen depreciation under dual stresses are combined to build the lifetime model. The adoption of thermal and electrical stresses overcomes the limitation of single stress, and junction temperature in accelerated degradation test as thermal stress is more reliable than ambient temperature in conventional ADT. Furthermore, verifying applications and cases studies are discussed to prove the practicability and generality of the proposed lifetime model. In addition, the lifetime model reveals that electrical stress is equally significant to the thermal stress in the degradation of LEDs, and therefore should not be ignored in the investigation on lumen decay of LEDs products
    corecore