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BSEC Method for Unveiling Open Clusters and its Application to Gaia DR3:83 New Clusters

Research in Astronomy and Astrophysics 2024年第5期24卷 169-184页

作者： Zhong-Mu Li Cai-yan mao Institute of Astronomy and Information Dali UniversityDali 671003China

Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint(EC) for the members of cluster candidates using the homogeneity of color excess,compared to typical blind search codes, it is called Blind Search-Extra Constraint(BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams(CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess(or twocolor) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large(e.g., ΔE(G_(BP)-G_(RP)) < 0.5 mag). It makes the CMDs of 15% clusters clearer(in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess con

关键词： Galaxy stellar content-(Galaxy:)open clusters and associations general-stars fundamental parameters

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Optimization Design of the Multi-Layer Cross-Sectional Layout of An Umbilical Based on the GA-GLM

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China Ocean Engineering 2024年第2期38卷 247-254页

作者： yanG Zhi-xun YIN Xu FAN Zhi-rui yan Jun LU Yu-cheng SU Qi mao yandong WANG Hua-lin Institute of marine machinery College of Mechanical and Electrical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDepartment of Engineering MechanicsDalian University of TechnologyDalian 116024China Ningbo Institube of Dalian University of Technology Ningbo 315040China

Marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with *** layout of these components directly affects manufacturing,operation and storage performances of the *** the multi-layer cross-sectional layout design of the umbilical,a quantifiable multi-objective optimization model is established according to the operation and storage *** the manufacturing factors,the multi-layering strategy based on contact point identification is introduced for a great number of functional ***,the GA-GLM global optimization algorithm is proposed combining the genetic algorithm and the generalized multiplier method,and the selection operator of the genetic algorithm is improved based on the steepest descent *** algorithm is used to find the optimal solution in the global space,which can converge from any initial layout to the feasible layout *** feasible layout solution is taken as the initial value of the generalized multiplier method for fast and accurate ***,taking umbilicals with a great number of components as examples,the results show that the cross-sectional performance of the umbilical obtained by optimization algorithm is better and the solution efficiency is ***,the multi-layering strategy is effective and *** design method proposed in this paper can quickly obtain the optimal multi-layer cross-sectional layout,which replaces the manual design,and provides useful reference and guidance for the umbilical industry.

关键词： umbilical cross-sectional layout multi-layers GA-GLM optimization

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Coinfection of SARS-CoV-2 Omicron variant and other respiratory pathogens in children

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World Journal of Pediatrics 2024年第1期20卷 92-96页

作者： Wei Li Bing-Han Wang Bao-Hai Chen Yi Sun Lin Li Wen-Qing Xiang Ahmed Faisal Ali Lin-Xuan Su Hai-yan mao Hong-Qiang Shen Qiang Shu Department of Clinical Laboratory Children's HospitalNational Clinical Research Center for Child HealthZhejiang University School of MedicineHangzhouChina School of Public Health Zhejiang University School of MedicineHangzhouChina Department of Information Center Children's HospitalZhejiang University School of MedicineHangzhouChina Zhejiang Provincial Center for Disease Control and Prevention HangzhouChina Department of Thoracic&Cardiovascular Surgery Children's HospitalNational Clinical Research Center for Child HealthZhejiang University School of MedicineHangzhouChina

Since the outbreak of coronavirus disease 2019(COVID-19),the entire world has been affected by the epidemic[1,2].On November 9,2021,a variant of the novel coronavirus B.1.1.529 was detected for the first time from case samples in South *** Omicron strain spread and mutated significantly *** variant has the characteristics of escape immunity,which can induce relatively extreme disease and reduce the neutralization of antibodies in vaccinators,and is more likely to be reinfected[3,4].The clinical presentation of severe acute respiratory syndrome coronavirus 2(SARSCoV-2)in children has mild symptoms and a lower risk of hospitalization and death.

关键词： respiratory immunity acute

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高中生物学“影响酶活性的因素”的释疑

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生物学教学 2024年第4期49卷 77-79页

作者：毛艳中国人民大学附属中学分校北京100086

本文从不同版本的教材对酶活性概念的表述入手,结合米氏方程解释酶浓度、底物浓度对酶活性的影响,加深对“影响酶活性的因素”的理解与认识,为一线教学提供新思路。

关键词：高中生物学酶活性影响因素

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Comparison of ovarian preservation versus oophorectomy on fertility outcomes in patients with endometriosis post-laparoscopic surgery:A prospective study

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World Journal of Clinical Cases 2024年第21期12卷 4652-4660页

作者： Jin-Jin Zhou Ke Yu Hai-yan mao Cen Li Department of Gynecology Affiliated Hospital of Yangzhou UniversityYangzhou 225001Jiangsu ProvinceChina Department of Oncology Affiliated Hospital of Yangzhou UniversityYangzhou 225001Jiangsu ProvinceChina

BACKGROUND Endometriosis is a chronic inflammatory condition affecting a significant proportion of women of reproductive *** laparoscopic surgery is commonly the preferred treatment,the decision to preserve or remove the ovaries remains *** studies have yielded inconsistent results regarding the impact of ovarian preservation vs oophorectomy on fertility outcomes and disease *** prospective study aimed to address this knowledge gap by comparing the effects of these surgical approaches on spontaneous pregnancy rates,time to pregnancy,recurrence rates,and postoperative pain in patients with *** To compare the reproductive outcomes and recurrence rates between ovarian preservation and oophorectomy in women undergoing laparoscopic surgery for *** This study was conducted at a tertiary care hospital between January 2019 and December 2023.A total of 312 women aged 18 to 40 years,diagnosed with endometriosis and undergoing laparoscopic surgery,were *** patients were categorized into the ovarian preservation group(n=204)and the oophorectomy group(n=108).The primary outcome measure was the achievement of spontaneous pregnancy within 24 months *** outcomes included time to spontaneous pregnancy,recurrence rates,and postoperative pain *** The ovarian preservation group exhibited a significantly higher spontaneous pregnancy rate than that in the oophorectomy group(43.6%vs 28.7%,P=0.006).Moreover,the median time to spontaneous pregnancy was shorter in the ovarian preservation group(8.2 months vs 11.4 months,P=0.018).Nonetheless,endometriosis recurrence was more prevalent in the ovarian preservation group(22.1%vs 11.1%,P=0.014).The postoperative pain scores demonstrated similar improvements in both groups,with no significant differences *** analyses indicated that the benefit of ovarian preservation on spontaneous pregnancy rates was more evident among youn

关键词： Endometriosis Ovarian Pregnancy Oophorectomy Laparoscopic Spontaneous pregnancy

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马尔科夫链通信拓扑下的车辆队列最优能耗控制

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控制与决策 2024年第1期39卷 161-170页

作者：闫茂德君萌萌左磊长安大学电子与控制工程学院西安710064

针对马尔科夫链通信拓扑下的车辆队列控制问题,综合考虑车辆队列的非线性动力学模型和行驶能耗优化目标,提出一种基于分布式状态观测器的车辆队列能耗优化控制方法.由于在马尔科夫链通信拓扑下,部分车辆获取的邻居车辆信息具有动态切换... 详细信息

针对马尔科夫链通信拓扑下的车辆队列控制问题,综合考虑车辆队列的非线性动力学模型和行驶能耗优化目标,提出一种基于分布式状态观测器的车辆队列能耗优化控制方法.由于在马尔科夫链通信拓扑下,部分车辆获取的邻居车辆信息具有动态切换特性,严重影响了车辆队列控制算法的有效性和稳定性.鉴于此,首先,设计一种用于估计领航车辆状态信息的状态观测器,有效避免通讯拓扑切换对队列控制系统造成的干扰;然后,结合车辆的非线性动力学模型与队列优化目标,构建一种基于指数折扣函数的车辆队列能耗优化框架,将车辆队列的能耗优化问题转化为Riccati方程的求解问题,进而得到车辆队列的最优能耗控制输入,在此基础上,通过构造动态通信拓扑下的李雅普诺夫函数,分析车辆队列控制系统的稳定性条件,即只要每个可能的通信拓扑均需包含一个以领航车辆为根的有向生成树,就可使得该车辆队列控制系统满足稳定性和队列稳定性;最后,通过数值仿真验证所提出控制算法的可行性和有效性.

关键词：最优控制车辆队列动态拓扑马尔科夫链状态观测器非线性动力学

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Analysis of long-term outcome of modified gastric bypass for type 2 diabetes mellitus in Chinese patients

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World Journal of Clinical Cases 2024年第25期12卷 5697-5705页

作者： Ying Xing Ri-Xing Bai You-Guo Li Jun Xu Zhi-Qiang Zhong Ming yan Wen-mao yan Department of General Surgery Beijing Tiantan HospitalBeijing 100170China

BACKGROUND Bariatric and metabolic surgery have been routinely performed following the rapid increase in obesity and metabolic diseases *** all evolving procedures,Roux-en-Y gastric bypass(RYGB)is considered the gold standard for surgical treatment of patients with type 2 diabetes mellitus(T2DM)and *** was introduced in China nearly 20 years ago,but the number of RYGB surgeries only accounts for 3.1%of the total number of weight loss and metabolic surgeries in China,it’s effect on Chinese people still needs further *** To investigate the effect and safety of a modified gastric bypass performed in Chinese patients with *** Patients with obesity and T2DM who underwent modified gastric bypass,with>5-year follow-up data,were *** All 37 patients underwent uneventful laparoscopic surgery,no patient was switched to laparotomy during the surgery,and no severe complications were *** weight and body mass index of the patients reduced from 84.6±17.3(60.0–140.0)kg and 30.9±5.0(24.7–46.2)kg/m2 to 67.1±12.2(24.7–46.2)kg and 24.6±3.9(17.7–36.5)kg/m2,respectively,and fasting plasma glucose and glycated hemoglobin decreased from 7.4±3.4 mmol/L and 8.2%±1.7%preoperatively to 6.5±1.3 mmol/L and 6.5%±0.9%5-years postoperatively,*** 29.7%(11/37)of the patients used hypoglycemic drugs 5-years postoperatively,and the complete remission rate of T2DM was 29.7%(11/37).Triglyceride level reduced significantly but high-density lipoprotein increased significantly(both P<0.05)compared with those during the preoperative *** and renal function improved significantly postoperatively,and binary logistic regression analysis revealed that the patients’preoperative history of T2DM and fasting C-peptide were significant prognostic factors influencing complete T2DM remission after RYGB(P=0.006 and 0.012,respectively).CONCLUSION The modified gastric bypass is a safe and feasible procedure for Chinese patients with obesity an

关键词： Laparoscopic Roux-en-Y gastric bypass Chinese patients Metabolic surgery Bariatric surgery Type 2 diabetes mellitus

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考虑3种时延的车辆队列控制系统稳定性

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交通运输工程学报 2024年第2期24卷 254-266页

作者：朱旭孙卓张泽华闫茂德长安大学电子与控制工程学院陕西西安710064

针对含输入时延、跟随车之间的通信时延、领航车广播时延的车辆队列控制系统,研究了其内部稳定性和队列稳定性;在内部稳定性方面,提出了一种融合克罗内克和与特征根聚类(CTCR)法的方法,获得了系统内部稳定的充分必要条件;在队列稳定性方... 详细信息

针对含输入时延、跟随车之间的通信时延、领航车广播时延的车辆队列控制系统,研究了其内部稳定性和队列稳定性;在内部稳定性方面,提出了一种融合克罗内克和与特征根聚类(CTCR)法的方法,获得了系统内部稳定的充分必要条件;在队列稳定性方面,为了保证干扰沿车辆队列向后传播不扩散,给出了队列稳定的充分条件,揭示了队列稳定性独立于跟随车之间的通信时延;在此基础上,给出了可保证队列稳定的时延上界与车辆控制器增益设计范围。仿真结果表明:当满足所提稳定性条件时,车辆队列控制系统可同时保持内部稳定和队列稳定;所提内部稳定性方法求解的时延边界是完整、精确的,理论推导结果与仿真试验结果的误差小于0.1 s,且仿真时间比Bézout结式消元快2个数量级,比Sylvester结式消元快3个数量级,表明该方法大幅度降低了传统特征根聚类法的运算量;车间状态误差可在15 s内快速减小并趋近于0;在所有车辆恒速行驶时,车间保持50 m期望安全距离;在领航车以0.4 m·s^(-2)加速和0.6 m·s^(-2)减速过程中,跟随车的速度和加速度随领航车变化,车辆位置误差小于0.5 m,且沿车辆队列向后传播不扩散。

关键词：智能交通车辆队列克罗内克和特征根聚类输入时延通信时延内部稳定队列稳定

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地方政府专项债券风险处置的二元结构及其法治化进路

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中国政法大学学报 2024年第2期 105-117页

作者：毛彦深圳大学法学院

地方政府专项债券遵循着项目收益与融资自求平衡的财政逻辑。这就要求专项债券风险处置除了关注财政风险的一般逻辑以外,更加注重项目风险的治理,继而形成“项目风险—财政风险”的二元结构。其中,专项债券项目风险可以划分为项目取消... 详细信息

地方政府专项债券遵循着项目收益与融资自求平衡的财政逻辑。这就要求专项债券风险处置除了关注财政风险的一般逻辑以外,更加注重项目风险的治理,继而形成“项目风险—财政风险”的二元结构。其中,专项债券项目风险可以划分为项目取消与项目失败,分门别类地予以处置。财政风险处置有必要破除地方政府的无限连带责任,依据专项债券的财政逻辑与各主体对项目的控制程度,制定专项债券财政风险的分配方案。归根结底,践行专项债券风险处置的法治化,从形式合法性和实质正当性的维度,明确法律授权、厘清法律关系、保障投资者权利,才是处置专项债券风险与防范系统性风险的根本之道。

关键词：地方债专项债券项目风险财政风险风险处置

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《红楼梦》缘何“说不尽”

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求是学刊 2024年第2期51卷 157-168页

作者：陈才训毛艳秋南开大学文学院天津300071 黑龙江大学文学院哈尔滨150080

曹雪芹屡屡以隐晦婉曲的“春秋笔法”叙事写人,使《红楼梦》颇多“烟云模糊处”;他又“远师楚人”,以比兴寄托之象征手法塑造意象化人物,并通过系统的叙事意象寄寓情志;“一芹一脂”共同塑成了充满“矛盾”与张力的开放性小说文本形态;... 详细信息

曹雪芹屡屡以隐晦婉曲的“春秋笔法”叙事写人,使《红楼梦》颇多“烟云模糊处”;他又“远师楚人”,以比兴寄托之象征手法塑造意象化人物,并通过系统的叙事意象寄寓情志;“一芹一脂”共同塑成了充满“矛盾”与张力的开放性小说文本形态;经学阐释传统之“过度阐释”与“强制阐释”对小说批评领域的强势介入:这些都在不同程度上左右着人们对《红楼梦》的阐释维度。正因《红楼梦》呈现出“伟大的混沌”状态,阐释者才会歧见纷出,从而成就了其“说不尽”的艺术魅力。

关键词：《红楼梦》曲笔人物意象与叙事意象开放性文本 “无结局”小说过度阐释与强制阐释

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