47 research outputs found
Butterfly Optimization Algorithm for Chaotic Feedback Sharing and Group Synergy
A butterfly optimization algorithm (BOA) based on chaotic feedback sharing and group synergy (CFSBOA) is proposed to solve the shortcomings of low precision and easy to fall into local optimum. Firstly, using Hénon chaos to initialize the population can make the population cover the search blind area as much as possible, increase the diversity of the population, and improve the ability of optimizing the algorithm. Secondly, using the ideas of positive and negative feedback mechanism in feedback control circuit, it builds butterfly feedback shared communication network, allowing individuals to receive information from multiple directions to help populations of positioning the location of the optimal solution and perform careful search, enhance the ability to escape from local optimum and accelerate the algorithm convergence speed. Finally, the collective synergistic effect mechanism is used to improve and balance the global and local search ability and enhance the global and local optimization ability of the algorithm. The performance of the improved butterfly optimization algorithm is verified by using different dimension benchmark test functions, statistical test, Wilcoxon test and multiple types of CEC2014 partial functions. Compared with the new improved butterfly algorithm and other swarm intelligence algorithms, the experimental results show that the proposed algorithm has obvious advantages
Scoliosis Related Information on the Internet in China: Can Patients Benefit from This Information?
Background: There has been an increasing popularity of searching health related information online in recent years. Despite that considerable amount of scoliosis patients have shown interest in obtaining scoliosis information through Internet, previous studies have demonstrated poor quality of online information. However, this conclusion may vary depending on region and culture. Since China has a restricted Internet access outside of its borders, the aim of this study is to evaluate the quality of scoliosis information available online using recognized scoring systems and to analyze the Internet as a source of health information in China.
Methods: A survey-based questionnaire was distributed to 280 respondents at outpatient clinics. Information on demographics and Internet use was collected. Binary logistic analysis was performed to identify possible predictors for the use of Internet. In addition, the top 60 scoliosis related websites assessed through 4 search engines were reviewed by a surgeon and the quality of online information was evaluated using DISCERN score and JAMA benchmark.
Results: Use of the Internet as a source for scoliosis related information was confirmed in 87.8% of the respondents. College education, Internet access at home and urban residence were identified as potential predictors for Internet use. However, the quality of online scoliosis related information was poor with an average DISCERN score of 27.9±11.7 and may be misleading for scoliosis patients.
Conclusion: The study outlines the profile of scoliosis patients who use the Internet as a source of health information. It was shown that 87.8% of the scoliosis patients in outpatient clinics have searched for scoliosis related information on Internet. Urban patients, higher education and Internet access at home were identified as potential predictors for Internet search. However, the overall quality of online scoliosis related information was poor and confusing. Physician based websites seemed to contain more reliable information
Experimental study on combustion optimization to alleviate fouling on heating surface of a Zhundong coal Boiler
In 2021, the price of most of the domestic coal skyrocketed, affecting the stable supply of electric power supply in some regions, while the price of Xinjiang Zhundong coal remains stable at a low level. Thus, the study of safe and stable large-scale combustion of Zhundong coal in boilers is more and more important for the energy supplyHowever, fouling and slagging often occur on the heating surfaces of the boiler due to the characteristics of Zhundong coal and the high temperature of the flue gas. The effects of the operating parameters, including the primary air velocity, operating oxygen content, air staging and coal fineness on the combustion temperature and NOx emission were investigated on a four-corner tangentially fired boiler of 660 MW capacity, which burned 95% Zhundong coal to get the relevant control criterion. Based on the research, the improvement of control function for contamination of heating surfaces was implemented under steady and dynamic working conditions. Finally, the influence of the improvement on the contamination of the heating surfaces was proved by the method of the contamination monitoring of heated surfaces. The results show that, at 660 MW load condition, the operating oxygen content had the most obvious influence on the flue gas temperature at the outlet of the furnace. The flue gas temperature decreased 99 °C when it increased from 2.0% to 3.5%. The reduction of the operating oxygen content and the local mean stoichiometric ratio of the main combustion zone could lead to a significant reduction of NOx emission and the change of the coal fineness had no obvious effect on NOx emission. After the improved control function was implemented, the rate of flue gas temperature decreased from 6.18 to 4.26 °C min−1 during the load increase process, the maximum temperature decreased from 1104 to 1023 °C under 660 MW. The heat absorption ratio of the platen superheater, low-temperature superheater and low-temperature reheater increased by 0.6%, 1.6% and 0.9%, respectively, indicating that the fouling and slagging was significantly reduced. At 330 MW load condition, increasing the coal fineness R90 to around 4.9% of the uppermost mill could effectively reduce the flue gas temperature near the bottom of the high-temperature reheater, reduce the deposition of combustible matter and fly ash, and inhibit the formation of fouling and slagging
Combination optimization method of grid sections based on deep reinforcement learning with accelerated convergence speed
A modern power system integrates more and more new energy and uses a large number of power electronic equipment, which makes it face more challenges in online optimization and real-time control. Deep reinforcement learning (DRL) has the ability of processing big data and high-dimensional features, as well as the ability of independently learning and optimizing decision-making in complex environments. This paper explores a DRL-based online combination optimization method of grid sections for a large complex power system. In order to improve the convergence speed of the model, it proposes to discretize the output action of the unit and simplify the action space. It also designs a reinforcement learning loss function with strong constraints to further improve the convergence speed of the model and facilitate the algorithm to obtain a stable solution. Moreover, to avoid the local optimal solution problem caused by the discretization of the output action, this paper proposes to use the annealing optimization algorithm to make the granularity of the unit output finer. The proposed method in this paper has been verified on an IEEE 118-bus system. The experimental results show that it has fast convergence speed and better performance and can obtain stable solutions
Population Genetic Diversity and Phylogenetic Characteristics for High-Altitude Adaptive Kham Tibetan Revealed by DNATyperTM 19 Amplification System
Tibetans residing in the high-altitude inhospitable environment have undergone significant natural selection of their genetic architecture. Recently, highly mutational autosomal short tandem repeats were widely used not only in the anthropology and population genetics to investigate the genetic structure and relationships, but also in the medical genetics to explore the pathogenesis of multiple genetic diseases and in the forensic science to identify individual and parentage relatedness. However, genetic variants and forensic efficiency of DNATyperTM 19 amplification system and genetic background of Kham Tibetan remain uncharacterized. Thus, we genotyped 19 forensic genetic markers in 11,402 Kham Tibetans to gain insight into the genetic diversity of Chinese high-altitude adaptive population. Highly discriminating and polymorphic forensic measures were observed, which indicated that this new-developed DNATyper 19 PCR amplification is suitable for routine forensic identification purposes and Chinese national DNA database establishment. Pairwise genetic distances among the comprehensive population comparisons suggested that this high-altitude adaptive Kham Tibetan has genetically closer relationships with lowlanders of Tibeto-Burman-speaking populations (Chengdu Tibetan, Liangshan Tibetan, and Liangshan Yi). Genetic substructure analyses via phylogenetic reconstruction, principal component analysis, and multidimensional scaling analysis in both nationwide and worldwide contexts suggested that the genetic proximity exists along the linguistic, ethnic, and continental geographical boundary. Further studies with whole-genome sequencing of modern or archaic Kham Tibetans would be useful in reconstructing the Tibetan population history
Application of Improved Equilibrium Optimizer Algorithm to Constrained Optimization Problems
Aiming at the problems of the equilibrium optimizer algorithm, such as difficult balance between population exploration and exploitation, insufficient information of particle evolution and prematurity, an improved equilibrium optimizer algorithm is proposed. Firstly, in the iterative stage optimized by the algorithm, the sinusoidal pool strategy is used to balance the exploration and development capabilities dynamically. In the early stage of iteration, a large range of global exploration is carried out through the sinusoidal decrease of fixed angular frequency to expand the algorithm to explore unknown areas in the search space and enhance the ability of discovering potential high-quality particles. At the end of iteration, local exploitation is carried out by sinusoidal increase of changing angular frequency to balance exploration and exploitation adaptively and improve the optimization accuracy of the algorithm. Secondly, the adaptive priority gravity strategy introduces the current optimal particle information to overcome the lack of evolution information, enriches the evolution information of the population particles by incorporating the uniform distribution and beta distribution together, improves the information exchange rate between particles, enhances the escape of the particles from the local area, and achieves the goal of guiding the population to converge rapidly towards the global optimum. Finally, 16 benchmark functions, CEC2017 functions, Friedman test, Wilcoxon rank sum test and two real-world engineering constraint optimization problems are used to test the optimization ability of the proposed algorithm. Experimental results show that the proposed algorithm has higher optimization accuracy and faster convergence speed compared with other new proposed intelligent algorithms
Emission Characteristics of NO
A large amount of NOx will be produced during the combustion process of waste energetic materials (EMs), which is extremely harmful to human health and ecological environment, and has become an urgent problem for all countries to solve. In this paper, the NOx emission characteristics of four typical types of waste EMs (double-base propellant, TNT, triple-base propellant and RDX) under different temperature and atmosphere conditions were studied by tube furnace experiment. The results showed that under the condition of nitrogen environment, with the increase of temperature, the combustion reaction of waste EMs was accelerated, NOx emission and nitrogen conversion rate decreased. Under the same experimental conditions, the nitrogen content of waste EMs was not proportional to nitrogen conversion. With the increase of oxygen content, NOx emissions and nitrogen conversion rate increased, which was not conducive to the control of NOx emissions. Therefore, the waste EMs burned in 1000 ℃ and nitrogen environment, the emission of NOx was the lowest. The results of this study provide reliable data support for the realization of green and clean burning of waste EMs
The protective effects of Zhen-Wu-Tang against cisplatin-induced acute kidney injury in rats.
Acute kidney injury (AKI) is a common clinical condition that confers a risk of progression of chronic kidney disease and a high risk of death. The purpose of the current study is to investigate the anti-apoptotic and anti-fibrotic effects of Zhen-Wu-Tang (ZWT) on cisplatin (CIS)-induced renal injury and elucidate the involvement of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), the PI3K/Akt signaling pathway, transforming growth factor (TGF)-β and the Wnt/β-catenin signaling pathway in the positive effects of Zhen-Wu-Tang on the kidneys. Wistar rats were randomly assigned into six groups of 6 rats each as follows: normal control 1; normal control 2; CIS 1 and CIS 2, which received single intraperitoneal injections of CIS (6 mg/kg); CIS+ZWT 4 and CIS+ZWT 10, which received ZWT (1 ml/100 g/day, ig) starting days after the CIS injection for 4 and 10 days, respectively. Hematoxylin-eosin (H&E) staining was performed to identify the amelioration of histopathological changes in the kidneys and apoptosis of the renal proximal tubular cells. Picrosirius red staining was used to evaluate renal fibrosis after ZWT treatment. The relationship between ZWT and the upregulation of Nrf2, phosphorylation of Akt, and the downregulation of TGF-β and WNT/β-catenin were determined by Western blotting. At the end of the experiment, serum was isolated from the orbital blood of rats, and blood urea nitrogen (BUN) and creatinine (Cr) levels were measured. The results showed that ZWT restored the histological alterations, aberrant collagen deposition in the kidneys and the BUN and Cr levels that were increased by CIS. Treatment with ZWT reduced the expression levels of TGF-β and Wnt and increased the expression levels of Nrf2, PI3K and Akt in the CIS-exposed kidney tissues. Furthermore, ZWT downregulated apoptosis and fibrosis by modulating the expression levels of caspase-3, Bax and alpha-smooth muscle actin (α-SMA). In conclusion, this study provides evidence for the anti-fibrotic and anti-apoptotic roles of ZWT in CIS-induced experimental kidney injury
Efficacy of breast reconstruction for N2‐3M0 stage female breast cancer on breast cancer‐specific survival: A population‐based propensity score analysis
Abstract Background The efficacy of breast reconstruction for patients with N2‐3M0 stage female breast cancer (FBC) remained unclear due to the lack of randomized clinical trials. This retrospective study aimed to explore the efficacy of breast reconstruction for patients with N2‐3M0 stage FBC. Methods Two thousand five hundred forty‐five subjects with FBC staged by N2‐3M0 from 2010 to 2016 were retrieved from the Surveillance, Epidemiology, and End Results database. Generalized boosted model (GBM) and propensity score matching (PSM) analyses and multivariable Cox analyses were employed to assess the clinical prognostic effect of postmastectomy reconstruction for patients with N2‐3M0 stage FBC in breast cancer‐specific survival (BCSS). Results Totally, 1784 candidates underwent mastectomy alone (mastectomy group), and 761 candidates underwent postmastectomy reconstruction (PMbR group), with 418 breast‐specific deaths after a median follow‐up time of 57 months (ranging from 7 to 227 months). BCSS in the mastectomy group showed no statistical difference from that in the PMbR group in the PSM cohort (HR = 0.93, 95% CI: 0.70–1.25, p = 0.400) and GBM cohort (HR = 0.75, 95% CI: 0.56–1.01, p = 0.057). In the multivariate analyses, there was no difference in the effect of PMbR and mastectomy on BCSS in the original cohort (HR = 0.85, 95% CI: 0.66–1.09, p = 0.197), PSM cohort (HR = 0.86, 95% CI: 0.64–1.15, p = 0.310), and GBM cohort (HR = 0.84, 95% CI: 0.61–1.17, p = 0.298). Triple‐negative breast cancer (TNBC) was a detrimental factor affecting BCSS for patients in the PMbR group. Conclusions Our study demonstrated that PMbR is an oncologically safe surgical treatment and can be widely recommended in clinics for females with non‐TNBC staged by T0‐3N2‐3M0
Genetic variation and population structure analysis of Chinese Wuzhong Hui population using 30 Indels
Background: Insertions and deletions (Indels) have been used in routine forensic studies, archaeology, and population genetics. They have certain advantages, such as absence of stutter, small amplicon lengths, and low mutation rates. The genetic variations and forensic features of Indels in the Wuzhong Hui population are, as yet, unclear. Aim: To investigate the genetic polymorphisms of 30 Indels in Wuzhong Hui people and explore their genetic relationship with 48 reference populations from all over the world. Subjects and methods: We genotyped 30 Indels included in the Investigator DIPplex Kit in 156 Wuzhong Hui individuals. The genetic polymorphisms and population genetic relationships were analysed and explored via pairwise Fst, principal component analysis, multidimensional scaling plots, phylogenetic tree, and structure. Results: The combined power of discrimination (CPD) and the combined probability of exclusion (CPE) were 0.9999999999899 and 0.9880, respectively. Population genetic diversity and affinity were associated with geographic origin and linguistic affiliation. Conclusions: The 30 Indels can be utilised as an important tool in forensic personal identification and as a supplementary method in paternity testing in Wuzhong Hui. The Wuzhong Hui people have a close genetic relationship with populations of geographical proximity and Sinitic-speaking populations, while they are different from other continental populations and Turkic-speaking populations