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71.
A distributed hydrological model, YHyM, was integrated with the export coefficient concept and applied to simulate the nutrient load in the Mekong River Basin. In the validation period (1992–1999), Nash–Sutcliffe efficiency was 76.4% for discharge, 65.9% for total nitrogen, and 45.3% for total phosphorus at Khong Chiam. Using the model, scenario analysis was then performed for the 2020s taking into account major anthropogenic factors: climate change, population, land cover, fertilizer use, and industrial waste water. The results show that the load at Kompong Cham in 2020s is 6.3 × 104 tN a− 1 (+ 13.0% compared to 1990s) and 4.3 × 103 tP a− 1 (+ 24.7%). Overall, the noticeable nutrient sources are cropland in the middle region and urban load in the lower region. The installation of waste water treatment plants in urban areas possibly cut 60.6%N and 19.9%P of the estimated increase in the case without any treatment.  相似文献   
72.
73.
Photovoltaics (PV) output prediction, which is indispensable for power system operation, can affects demand and supply adjustment adversely when large prediction error occurs. Thus, the reduction of large error as well as average error is required in PV power prediction. In 2019, the operation of the Meso-scale Ensemble Prediction System (MEPS) of numerical weather prediction started from the JapanMeteorological Agency, and the amount of forecasting information would be potentially useful for the improvement of PV power prediction. However, very few studies on inputting multiple meteorological elements of the MEPS have been reported. In this paper, we newly develop the prediction model for an area day-ahead PV power output composed of Just-In-Time Modeling (JIT Modeling) with multiple elements of theMEPS. The developed method achieves precise forecasts with low computational load by both selecting meteorological elements valid for improving prediction accuracy and adequately devising the structure of JIT Modeling. Some numerical examples demonstrating the effectiveness of the developed method are also presented. In particular, the proposed method reduces large error significantly.  相似文献   
74.
The effect of axial mixing in an aeration tank of activated sludge process operating with a mode of tapered aeration has been studied from the view point of a heterogenous system. The dispersion model is applied to represent the flow system with tapered aeration, by which a formation of non-uniform axial mixing with an abrupt change of mixing intensity at the section-boundary is assumed.A numerical technique for solving the multi-point boundary-value problem associated with the system-model of tapered aeration is specifically introduced. By using this computational scheme, several simulations with different operating conditions resulting in various patterns of axial mixing; heterogenous, homogeneous, non-uniform and uniform axial mixing, are carried out.  相似文献   
75.
One of the most promising new technologies for widespread application is image annotation and retrieval. Nevertheless, this task is very difficult to accomplish as target images differ significantly in appearance and belong to a wide variety of categories. In this paper, we propose a new image annotation and retrieval method for miscellaneous weakly labeled images, by combining higher-order local auto-correlation (HLAC) features and a framework of probabilistic canonical correlation analysis. The distance between images can be defined in the intrinsic space for annotation using conceptual learning of images and their labels. Because this intrinsic space is highly compressed compared to the image feature space, our method achieves both faster and more accurate image annotation and retrieval. The HLAC features are powerful global features with additive and position invariant properties. These properties work well with images, which have an arbitrary number of objects at arbitrary locations. The proposed method is shown to outperform existing methods using a standard benchmark dataset.  相似文献   
76.
The motion behaviors of vertebrates require the correct coordination of the muscles and of the body limbs even for the most stereotyped ones like the rhythmical patterns. It means that the neural circuits have to share some part of the control with the material properties and the body morphology in order to rise any of these motor synergies. To this respect, the chemical downward neuromodulators that supervise the pattern generators in the spinal cord create the conditions to merge (or to disrupt) them by matching the phase of the neural controllers to the body dynamics. In this paper, we replicate this control based on phase synchronization to implement neuromodulators and investigate the interplay between control, morphology and material. We employ this mechanism to control three robotic setups of gradual complexity and actuated by McKibben type air muscles: a single air muscle, an elbow-like system and a leg-like articulation. We show that for specific values, the control parameters modulate the internal dynamics to match those of the body and of the material physics to either the rhythmical and non-rhythmical gait patterns.  相似文献   
77.
Febrile Infection-Related Epilepsy Syndrome (FIRES) is a unique catastrophic epilepsy syndrome, and the development of drug-resistant epilepsy (DRE) is inevitable. Recently, anakinra, an interleukin-1 receptor antagonist (IL-1RA), has been increasingly used to treat DRE due to its potent anticonvulsant activity. We here summarized its effects in 38 patients (32 patients with FIRES and six with DRE). Of the 22 patients with FIRES, 16 (73%) had at least short-term seizure control 1 week after starting anakinra, while the remaining six suspected anakinra-refractory cases were male and had poor prognoses. Due to the small sample size, an explanation for anakinra refractoriness was not evident. In all DRE patients, seizures disappeared or improved, and cognitive function improved in five of the six patients following treatment. Patients showed no serious side effects, although drug reactions with eosinophilia and systemic symptoms, cytopenia, and infections were observed. Thus, anakinra has led to a marked improvement in some cases, and functional deficiency of IL-1RA was indicated, supporting a direct mechanism for its therapeutic effect. This review first discusses the effectiveness of anakinra for intractable epileptic syndromes. Anakinra could become a new tool for intractable epilepsy treatment. However, it does not currently have a solid evidence base.  相似文献   
78.
A generalized steady-state model is being developed for an internal heat integrated distillation column (IHIDiC). A procedure incorporating the Newton-Rapheon method is devised for solving the model equations. Separation of an ethanol-water binary mixture is simulated and analyzed with the model, Two pinch points are found within the process, making the separation ex-tremely difllcult and expensive. Two sharp fronts in the temp-erature and the composition profiles are being observed. With the introduction of heat integration, satisfactory separation may be obtained in a limited number of stages with lower reflux ratios. Increasing the pressure difference between the rectifylng and the strlpping sectlons, however, would bring about a reduced relative volatility between the two components involved, creating adverse separation performances. It is obvious that optimigation of the IHIDiC is of prime importance.  相似文献   
79.
The operation of an ideal heat integrated dlstillation columan (HIDiC) is addressed .Five Kinds of control configurations, i.e. single-loop control, multi-loop control, multivariable internal model control (IMC), modified multlvariable internal model control (MIMC) and nonlinear process model-based control (NPMC), are designed and applied to the process. Simulation results demonstrate that all of the above control confaguratloam ere valid for product quality control. NPMC control configuration is found to be the best one among all the alternatives. It can readily realize setpoint transitions and conduct effectively against external disturbance. MIMC control configuration ranks second in the row for its regulatory responses to feed composition disturbances with relatively extended setting time, Next comes from the multi-loop control configuration, which is moee or lees handicapped by its greater deviations and overshootings. IMC control configuration can not compete with the multi-loop control configuration because it is extremely sensitive to operating condition changes. Single-ioop control configuration is the worst one among all the mentioned control configurations. Its responses for the uncoutrolled end products are extremely sluggish.  相似文献   
80.
Retinoid X receptor (RXR) agonists (rexinoids) are attracting much attention for their use in treatment of cancers, including tamoxifen-resistant breast cancer and taxol-resistant lung cancer, and metabolic disease. However, known RXR agonists have a highly lipophilic character. In addition, no subtype-selective RXR agonists have been found. We previously reported an RXRalpha-preferential agonist 4-[N-methanesulfonyl-N-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthyl)amino]benzoic acid (6 a). The RXR agonistic activity is much less than that of well-known RXR agonists. To develop potent, less-lipophilic, and subtype-selective RXR agonists, we created new RXR agonists possessing alkoxy and isopropyl groups as a lipophilic domain of the common structure of well-known RXR agonists. As a result, compounds possessing branched alkoxy groups, 6-[N-ethyl-N-(3-isopropoxy-4-isopropylphenyl)amino]nicotinic acid (NEt-3IP: 7 a) and 6-[N-ethyl-N-(3-isobutoxy-4-isopropylphenyl)amino]nicotinic acid (NEt-3IB: 7 c), showed RXR agonistic activity as potent as, or more potent than, the activities of representative RXR agonists. Moreover, NEt-3IP (7 a) was found to be the first RXRalpha/beta-selective (or RXRalpha/beta-dual) agonist. Being potent, less lipophilic, and having RXR subtype-selective activity, NEt-3IP (7 a) is expected to become a new drug candidate and to be a useful biological tool for clarifying each RXR subtype function.  相似文献   
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