In order to provide the ancillary service for smart grid, this paper proposes a modelling and control protocol design approach for the aggregation of heterogeneous thermostatically controlled loads ...(TCLs). A 2-D state bin is proposed to model the second-order TCL dynamics in a population model. Detailed procedure of calculating the transition probability in the system matrix is provided. In the controller design, a model predictive control (MPC) scheme is proposed to obtain the optimal control actions along the prediction horizon. In addition, implementation of the control signal for adjusting TCLs' statuses are also investigated with practical situations considered. Simulation results reveal the feasibility and efficacy of the proposed modelling and control approach when applied on a large population of TCLs. Some factors that may affect the service performance are also discussed in this paper.
•Light Gradient Boosting Machine (LightGBM) is used to forecast the price of cryptocurrency.•42 kinds of different features are extracted to describe the changes in the macro market.•The internal ...influence of different cryptocurrencies is considered in model construction.•LightGBM model shows higher accuracy and better robustness in forecasting.•Comprehensive strength of cryptocurrencies significantly impacts the forecasting performance.
Forecasting cryptocurrency prices is crucial for investors. In this paper, we adopt a novel Gradient Boosting Decision Tree (GBDT) algorithm, Light Gradient Boosting Machine (LightGBM), to forecast the price trend (falling, or not falling) of cryptocurrency market. In order to utilize market information, we combine the daily data of 42 kinds of primary cryptocurrencies with key economic indicators. Results show that the robustness of the LightGBM model is better than the other methods, and the comprehensive strength of the cryptocurrencies impacts the forecasting performance. This can effectively guide investors in constructing an appropriate cryptocurrency portfolio and mitigate risks.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The combined cooling, heating and power (CCHP) system – a typical representative of the decentralized energy system – has been increasingly attracting attention in academia and industries in recent ...years, thanks to its distinctive advantages of high system and economic efficiency, and less greenhouse gas (GHG) emissions. In this paper, the state of the art of CCHP research is surveyed. First, the development and working scheme of the CCHP system will be presented. Some analyses of the advantages of this system and a brief introduction of the related components are then given in the first part. In the second part of this paper, we elaborately introduce the prime mover and thermally activated facilities. Recent research progress on the management, control, system optimization and sizing will be summarized in the third part. The development of the CCHP system in representative countries and the development barriers will be discussed in the last part.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Using aggregated heterogeneous thermostatically controlled loads (TCLs) to provide ancillary services in a smart grid is a promising technique. This paper proposes an improved population model with ...lockout time considered to describe the aggregate dynamics. Based on that, a distributed model predictive control (DMPC) scheme is investigated to control a population of TCLs for the regulation service. Full derivations of the system model and the DMPC scheme are provided. A flexibility penalty is developed and added to the objective function to preserve the regulation flexibility. Simulation results, tested by real data, reveal the feasibility and effectiveness of the proposed method.
This paper studies the modeling and control methods for the provision of ancillary services through aggregating thermostatically controlled appliances (TCAs). A model predictive control (MPC) scheme ...is presented. Minimum ON/OFF time for protecting the TCA unit is explicitly described in the MPC scheme. A novel method of converting time-integrated interdependent logic conditions, which are for constraining the lockout effect, into inequalities is proposed in this paper. A case study is conducted with realistic data to validate the feasibility of the modeling and control approaches. Parametric studies in terms of temperature deadband width, ambient temperature, and lockout time are conducted to investigate the service quality in different circumstances. The test results reveal that a population of diversified TCAs can become a major source of providing ancillary service. The proposed approach can be specialized to deal with the pure ON/OFF control.
In this article, we describe a long-non-coding RNA (lncRNA) and disease association database (LncRNADisease), which is publicly accessible at http://cmbi.bjmu.edu.cn/lncrnadisease. In recent years, a ...large number of lncRNAs have been identified and increasing evidence shows that lncRNAs play critical roles in various biological processes. Therefore, the dysfunctions of lncRNAs are associated with a wide range of diseases. It thus becomes important to understand lncRNAs' roles in diseases and to identify candidate lncRNAs for disease diagnosis, treatment and prognosis. For this purpose, a high-quality lncRNA-disease association database would be extremely beneficial. Here, we describe the LncRNADisease database that collected and curated approximately 480 entries of experimentally supported lncRNA-disease associations, including 166 diseases. LncRNADisease also curated 478 entries of lncRNA interacting partners at various molecular levels, including protein, RNA, miRNA and DNA. Moreover, we annotated lncRNA-disease associations with genomic information, sequences, references and species. We normalized the disease name and the type of lncRNA dysfunction and provided a detailed description for each entry. Finally, we developed a bioinformatic method to predict novel lncRNA-disease associations and integrated the method and the predicted associated diseases of 1564 human lncRNAs into the database.
Recent studies have demonstrated that long non-coding RNAs (LncRNAs) can influence bone cell differentiation and formation. However, it is unclear whether lncRNA HCG18 is involved in osteoporosis ...(OP). This study was conducted to investigate the regulation of HCG18 in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs).
BMSCs were isolated and cultured from mouse pathological models and osteoporosis patients. RT-qPCR was performed to detect the expression of HCG18 and miR-30a-5p in BMSCs. The interaction between HCG18 and miR-30a-5p was analyzed by dual luciferase assay and RNA pulldown assay. The interaction between miR-30a-5p and NOTCH1 3'-UTR was analyzed by dual luciferase assay. RT-qPCR and Western blotting were used to detect the expression of osteogenic genes Runx2, OCN and OPN. Hindlimb-unloaded (HU) mice model was established, and HCG18 was knocked down on bone-formation surfaces by using lentivirus mediated shRNA transfection.
The expression of HCG18 was increased in BMSCs of OP patients, while the expression of miR-30a-5p was decreased. The expression of HCG18 and miR-30a-5p was negatively correlated in BMSCs. During the differentiation from BMSCs to osteoblasts, the expression of HCG18 was significantly downregulated, and the expression of miR-30a-5p was significantly upregulated. Overexpression of HCG18 was able to reverse the osteogenic-induced upregulation of miR-30a-5p expression, and knockdown of HCG18 further promoted the expression of miR-30a-5p. In addition, miR-30a-5p partially abolished the effect of HCG18 on osteogenic differentiation of BMSCs. NOTCH1 was a target protein of miR-30a-5p, and upregulation of NOTCH1 reversed the effect of miR-30a-5p on osteogenic differentiation of BMSCs. Furthermore, this study found that lentivirus mediated HCG18 knockdown on the bone-formation surfaces of hindlimb-unloaded (HU) mice partially alleviated unloading-induced bone loss CONCLUSIONS: HCG18 inhibited osteogenic differentiation of BMSCs induced by OP via the miR-30a-5p/NOTCH1 axis. HCG18 can be identified as a regulator of osteogenic differentiation of BMSCs.
► A new operation strategy for the CCHP system is proposed. ► The idea of ‘matching’ is conceived in the design of the operation strategy. ► The PGU capacity is optimized under the proposed operation ...strategy. ► Electric cooling to cool load ratio is optimized hourly. ► The proposed operational strategy outperforms the FEL and FTL strategies.
Performance and economical efficiency of the combined cooling, heating and power (CCHP) system mainly depend on the system structure, operation strategy and choice of facility capacity. This paper proposes a structural configuration of the CCHP system with hybrid chillers, consisting of a combined electric and absorption chiller, whose electric cooling to cool load ratio varies according to different electric and thermal loads in every hour. A new operation strategy, based on the variational electric cooling to cool load ratio, for the CCHP system with unlimited and limited power generation unit (PGU) capacity is investigated. Given the proposed operation strategy, an optimization algorithm is adopted to determine the optimal PGU capacity. In addition, a case study of a hypothetical hotel in Victoria, BC, Canada is conducted to verify the feasibility of the proposed CCHP system structure and the corresponding optimal operation strategy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This paper investigates the step tracking control problem for discrete-time nonlinear systems in a networked environment with a limited capacity. The nonlinear system is represented by a ...Takagi-Sugeno (T-S) fuzzy system, and a network-induced delay is incorporated in the modeling of the connection link. In order to compensate for the network link effects and eliminate the tracking error, we employ some techniques mainly used in the predictive control and the integral control. Moreover, a quadratic cost function which includes terms related to the performance of the system and the actuating capacity is used. We assume that the lumped network-induced delay lies within a known set, and that the occurrence probability for each element in the set is known a priori. Then, the delay information will be incorporated into the delay-dependent tracking controllers. The parameters for the tracking controller are derived by solving an optimization problem. A networked inverted pendulum is used to illustrate the efficacy of the proposed design method.
In vitro generation of functional gametes is a promising approach for treating infertility, although faithful replication of meiosis has proven to be a substantial obstacle to deriving haploid gamete ...cells in culture. Here we report complete in vitro meiosis from embryonic stem cell (ESC)-derived primordial germ cells (PGCLCs). Co-culture of PGCLCs with neonatal testicular somatic cells and sequential exposure to morphogens and sex hormones reproduced key hallmarks of meiosis, including erasure of genetic imprinting, chromosomal synapsis and recombination, and correct nuclear DNA and chromosomal content in the resulting haploid cells. Intracytoplasmic injection of the resulting spermatid-like cells into oocytes produced viable and fertile offspring, showing that this robust stepwise approach can functionally recapitulate male gametogenesis in vitro. These findings provide a platform for investigating meiotic mechanisms and the potential generation of human haploid spermatids in vitro.
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•Haploid spermatid-like cells (SLCs) were derived by stepwise differentiation of ESCs•This process completely recapitulated meiosis in vitro, meeting meiotic hallmarks•Intracytoplasmic injection of SLCs produced euploid and fertile offspring
In vitro production of haploid gametes could provide a treatment for infertility, but recapitulating meiosis in culture is a significant roadblock. Zhou et al. report the generation of haploid male gametes from mouse ESCs that can produce viable and fertile offspring, demonstrating functional reproduction of meiosis in vitro.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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