13 research outputs found
Accommodation capacity evaluation of renewable energy in power systems considering peak and frequency regulation
With the fast growth of renewable energy, the modern power systems are transitioning to the renewable energy dominated energy systems. However, the intrinsic intermittence and volatility of renewable energy also impose considerable challenges on the power system operation. Hence, it is of great significance to accurately evaluate the renewable energy accommodation capacity (REAC) in power system so as to effectively instruct the sustainable development of renewable energy and to alleviate the ongoing operational burdens. This paper proposes a novel evaluation method of REAC in power system comprehensively considering peak and frequency regulation. First, the mechanism and cost of deep peak regulation of thermal power units are deeply analyzed, and then the frequency dynamics response is modeled explicitly and simplified effectively. Next, a synthetic interaction model of “source-network-storage” is developed with diversified generation units, network and energy storage constraints. Furthermore, a multi-objective optimization model is established considering both economic and technical issues, and a REAC evaluation method is developed by integrating an incremental capacity augment approach with the proposed multi-objective model. Finally, the proposed REAC evaluation method is tested on the modified IEEE 39-bus system, and the numerical results verify the effectiveness of the proposed method
Understanding the factors of wearable devices among the patients with thyroid cancer: A modified UTAUT2 model.
Wearable devices hold promising prospects on a global scale, including in China. Thyroid cancer prevalence is notably high in China.This purpose of this researchwas to provide an updated theoretical model for assessing Chinese thyroid cancer patients' intentions towards wearable devices, based on the UTAUT2 framework, and to ascertain the factors that have an impact on these intents. A cross-sectional study with an institutional focus wasconducted from January 20, 2023, to June 30, 2023, at several general hospitals in China. Five hundred participants were recruited to identify predictors of wearable device use.The questionnaire survey about patients' intentionswas collected using a face-to-face method, employing a random sampling technique for patient selection. Four hundred sixty-nine individuals (93.8%) had the intention to use wearable devices. The intentions were highly impacted by performance expectancy (PE), effort expectancy (EE), social influence (SI), hedonic motivation (HM), price value (PV) and habit (HA). Usage intention (UI)was a statistically predictor of Usage behavior (UB). The facilitating condition(FC) was not significant. Gender positively moderated the relationship between EE and UI. Income positively moderated the relationship between all variables and UI.Overall, the utilization of wearable devices among patients diagnosed with thyroid cancer has demonstrated considerable potential. This study offers a series of suggestions for digital health developers,healthcare decision-makers,doctors and patients
The stress characteristics of plate-fin structures at the different operation parameters of LNG heat exchanger
In this paper, the stresses of plate-fin structures at the different operation parameters were analyzed in actual operation process of LNG plate-fin heat exchanger based on finite element method and thermal elastic theory. Stress characteristics of plate-fin structures were investigated at the different operation parameters of that. The results show that the structural failure of plate-fin structures is mainly induced by the maximum shear stress at the brazing filler metal layer between plate and fin while by the maximum normal stress in the region of brazed joint near the fin side. And a crack would initiate in brazed joint near the fin side. The maximum normal stress is also main factor to result in the structural failure of plate-fin structures at the different temperature difference (between Natural Gas (NG) and Mixture Refrigerant (MR)), MR temperature and NG pressure of LNG heat exchanger. At the same time, the peak stresses obviously increase as the temperature difference, MR temperature and NG pressure increase. These results will provide some constructive instructions in the safe operation of LNG plate-fin heat exchanger in a large-scale LNG cold-box
Research on Chinese Antarctic Data Directory System - Collecting, processing, examining and submitting data directory
Based on the general framework of ADDS (Antarctic Data Directory System) established by SCAR-COMNAP ad hoc Planning Group on Antarctic data management, the CN-ADDS (Chinese Antarctic Data Directory System) project is going on, of which the research and activity keeps to the available method and technique in ADDS development and allows for the Chinese specific status in Antarctic data management as well. At present, authoring and submitting timely Antarctic data directory in China is one of the key issues that is to be dealt with necessary. This paper aims at studying the technical procedure in collecting, processing, examining and submitting data directory. In additional, it also discusses the efficient collection of data directory, which needs the effort of administrative and technical support
The stress characteristics of plate-fin structures at the different operation parameters of LNG heat exchanger
In this paper, the stresses of plate-fin structures at the different operation parameters were analyzed in actual operation process of LNG plate-fin heat exchanger based on finite element method and thermal elastic theory. Stress characteristics of plate-fin structures were investigated at the different operation parameters of that. The results show that the structural failure of plate-fin structures is mainly induced by the maximum shear stress at the brazing filler metal layer between plate and fin while by the maximum normal stress in the region of brazed joint near the fin side. And a crack would initiate in brazed joint near the fin side. The maximum normal stress is also main factor to result in the structural failure of plate-fin structures at the different temperature difference (between Natural Gas (NG) and Mixture Refrigerant (MR)), MR temperature and NG pressure of LNG heat exchanger. At the same time, the peak stresses obviously increase as the temperature difference, MR temperature and NG pressure increase. These results will provide some constructive instructions in the safe operation of LNG plate-fin heat exchanger in a large-scale LNG cold-box
Acute kidney injury in patients with cancer receiving anti-PD-1/PD-L1 antibodies: incidence, risk factors, and prognosis
AbstractAnti-PD-1/PD-L1 antibodies are widely used in anti-cancer therapy. While they have improved cancer prognoses, immune-related adverse events, which can cause acute kidney injury (AKI), cannot be ignored. The purpose of this retrospective cohort study was to assess the incidence, risk factors, and prognosis of AKI associated with anti-PD-1/PD-L1 antibodies. Patients who received anti-PD-1/PD-L1 antibody treatment at our hospital between January 2018 and December 2022 were enrolled. Clinical information, combined medications, concomitant diseases, tumor types, and laboratory indicators were collected from patient records, and the incidence of AKI was determined. The risk factors for AKI were assessed using univariate and multivariate logistic regression analyses. Overall, 1418 patients were enrolled. The median follow-up time was 112 days and 92 (6.5%) developed AKI. The median time from the initial anti-PD-1/PD-L1 antibody treatment to AKI was 99.85 days. Head and neck cancer and combined use of diuretics, non-steroidal anti-inflammatory drugs (NSAIDs), lower hemoglobin level, and other types of chemotherapeutic drugs were independent risk factors for AKI. The complete recovery, partial recovery, non-recovery, and unknown AKI rates were 7.6%, 28.3%, 52.2%, and 11.9%, respectively. Kidney biopsies were performed on two patients with AKI and pathology confirmed diagnosis of acute tubulointerstitial nephritis. In this cohort, AKI was not uncommon in patients treated with anti-PD-1/PD-L1 antibodies; therefore, it is necessary to monitor renal function and identify AKI early, especially in patients with head and neck tumors. Improving anemia and minimizing the use of diuretics, NSAIDs, and chemotherapeutics may reduce AKI