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Comparative Analysis of Building Rating Systems and Occupant Rating Systems
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作者 Rana Al Kady Salah El-Haggar Ahmed El-Gendy 《Journal of Environmental Protection》 CAS 2023年第4期285-296,共12页
To begin with, rating systems are a beneficial tool in determining the efficiency of a building’s ability to utilise its resources effectively. In this study, the two elements under comparison are the Building Rating... To begin with, rating systems are a beneficial tool in determining the efficiency of a building’s ability to utilise its resources effectively. In this study, the two elements under comparison are the Building Rating Systems (BRSs) and Occupant Rating Systems (ORSs). The main objective of this paper is to be able to examine the most commonly applied international and national BRS and ORS and, based on that, discover the possibility of developing an integration of both the BRS and ORS into one rating system. Quite simply, a BRS is a method by which buildings are assessed and given a score based on numerous features such as the efficiency of each of the services, total energy consumption, and alternate options of consumption. There are various BRSs that are implemented globally, each with its own set of criteria and specifications. Thus, based on the analysis of the benefits and drawbacks of both types of rating systems, it could be deduced that a well-rounded rating system with all technical and non-technical aspects combined would be beneficial to both the efficiency of the building as well as the building occupants’ health and well-being. 展开更多
关键词 Building rating Systems Energy Efficiency Net-Zero Buildings OCCUPANCY rating Systems Renewable Energy Technologies
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Exploring the thermal stability of lithium-ion cells via accelerating rate calorimetry:A review
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作者 Dongxu Ouyang Mingyi Chen +3 位作者 Jingwen Weng Kuo Wang Jian Wang Zhirong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期543-573,I0012,共32页
Given the importance of lithium-ion cell safety,a comprehensive review on the thermal stability of lithium-ion cells investigated by accelerating rate calorimetry(ARC),is provided in the present work.The operating mec... Given the importance of lithium-ion cell safety,a comprehensive review on the thermal stability of lithium-ion cells investigated by accelerating rate calorimetry(ARC),is provided in the present work.The operating mechanism of ARC is discussed first,including the usage and the reaction kinetics.Besides that,the thermal stability of the cathode/anode materials at elevated temperatures is revealed by examining the impacts of some significant factors,i.e.,the lithium content,particle size,material density,lithium salt,solvent,additive,binder and initial heating temperature.A comparison of the common cathode materials indicates that the presence of Mn and polyanion could significantly enhance the thermal stability of cathode materials,while the doping of Al also helps to restrain the reactivity.Except for their high capacity,some alloy materials demonstrate more competitive safety than traditional carbon anode materials.Furthermore,the thermal behaviors of full cells under abusive conditions are reviewed here.Due to the sensitivity of ARC to the kinetic parameters,a reaction kinetic modeling can be built on the basis of ARC profiles,to predict the thermal behaviors of cell components and cells.Herein,a shortcircuit modeling is exampled. 展开更多
关键词 Accelerating rate calorimetry Electrode materials Full cells SAFETY MODELING
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SCIM: Incorporating secure communication and interference management in one operation
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作者 Zhao Li Pintian Lyu +3 位作者 Jun Li Zhixian Chang Jia Liu Zheng Yan 《Digital Communications and Networks》 SCIE CSCD 2023年第2期512-522,共11页
Due to the broadcast nature of wireless communications,users’data transmitted wirelessly is susceptible to security/privacy threats.Meanwhile,as a result of the limitation of spectrum resources,massive wireless conne... Due to the broadcast nature of wireless communications,users’data transmitted wirelessly is susceptible to security/privacy threats.Meanwhile,as a result of the limitation of spectrum resources,massive wireless connections will incur serious interference,which may damage the efficiency of data transmission.Therefore,improving both efficiency and secrecy of data transmission is of research significance.In this paper,we propose a wireless transmission scheme by taking both Secure Communication(SC)and Interference Management(IM)into account,namely SCIM.With this scheme,an SCIM signal is generated by the legitimate transmitter(Tx)and sent along with the desired signal,so that the SCIM signal can interact with and suppress the environmental interference at the legitimate receiver(Rx).Meanwhile,the SCIM signal may interfere with the eavesdropper in the coverage of legitimate transmission so as to deteriorate the eavesdropping performance.Therefore,the secrecy of desired transmission is improved.In this way,both the transmission efficiency and privacy are enhanced.Then,by taking various transmission preferences into account,we develop different implementations of SCIM,including Interference Suppression First SCIM(ISF-SCIM),Data Transmission First SCIM(DTF-SCIM),Anti-Eavesdropping First SCIM(AEF-SCIM),and Secrecy Rate Maximization SCIM(SRM-SCIM).Our in-depth simulation results have shown the proposed methods to effectively improve the efficiency and secrecy of the legitimate transmission. 展开更多
关键词 Physical-layer security Secure communication Anti-eavesdropping Interference management Secrecy rate
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The laparoscopic rating scale for the evaluation of working conditions for surgical treatment of super-obesity
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作者 Oral Ospanov 《Laparoscopic, Endoscopic and Robotic Surgery》 2023年第2期78-82,共5页
In this technical note,a novel rating scale(abdominal integral index)was introduced for assessing the conditions of the working laparoscopic space based on linear measurements to select the optimal one or two-stage su... In this technical note,a novel rating scale(abdominal integral index)was introduced for assessing the conditions of the working laparoscopic space based on linear measurements to select the optimal one or two-stage surgical treatment for super-obesity.Patients with the same height and similar BMI values had different rating scale scores,reflecting different conditions of laparoscopic bariatric surgery.The rating scale helps surgeons and patients make a safe option for surgery,depending on the experience of the surgeon and technical laparoscopic conditions. 展开更多
关键词 Bariatric surgery Laparoscopic rating scale Surgical working conditions SUPER-OBESITY
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Design of Online Vitals Monitor by Integrating Big Data and IoT
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作者 E.Afreen Banu V.Rajamani 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2469-2487,共19页
In this work,we design a multisensory IoT-based online vitals monitor(hereinafter referred to as the VITALS)to sense four bedside physiological parameters including pulse(heart)rate,body temperature,blood pressure,and... In this work,we design a multisensory IoT-based online vitals monitor(hereinafter referred to as the VITALS)to sense four bedside physiological parameters including pulse(heart)rate,body temperature,blood pressure,and periph-eral oxygen saturation.Then,the proposed system constantly transfers these signals to the analytics system which aids in enhancing diagnostics at an earlier stage as well as monitoring after recovery.The core hardware of the VITALS includes commercial off-the-shelf sensing devices/medical equipment,a powerful microcontroller,a reliable wireless communication module,and a big data analytics system.It extracts human vital signs in a pre-programmed interval of 30 min and sends them to big data analytics system through the WiFi module for further analysis.We use Apache Kafka(to gather live data streams from connected sen-sors),Apache Spark(to categorize the patient vitals and notify the medical pro-fessionals while identifying abnormalities in physiological parameters),Hadoop Distributed File System(HDFS)(to archive data streams for further analysis and long-term storage),Spark SQL,Hive and Matplotlib(to support caregivers to access/visualize appropriate information from collected data streams and to explore/understand the health status of the individuals).In addition,we develop a mobile application to send statistical graphs to doctors and patients to enable them to monitor health conditions remotely.Our proposed system is implemented on three patients for 7 days to check the effectiveness of sensing,data processing,and data transmission mechanisms.To validate the system accuracy,we compare the data values collected from established sensors with the measured readouts using a commercial healthcare monitor,the Welch Allyn®Spot Check.Our pro-posed system provides improved care solutions,especially for those whose access to care services is limited. 展开更多
关键词 Big data analytics blood pressure body temperature physiological parameters pulse rate sensors SPO2
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The Impact of Credit Ratings on Financial Performance (ROA) and Value Creation (Tobin’s Q)
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作者 Nazário Augusto de Oliveira Leonardo Fernando Cruz Basso 《Chinese Business Review》 2023年第2期69-85,共17页
This study employs a bibliometric and systematic approach to examine the impact of credit ratings as a measure of financial performance for companies listed in the S&P 500 index.The study identified a knowledge ga... This study employs a bibliometric and systematic approach to examine the impact of credit ratings as a measure of financial performance for companies listed in the S&P 500 index.The study identified a knowledge gap as only two researches were found,one suggesting and another using credit ratings to measure financial performance.Most researches use leverage,profitability,liquidity,and Share Return measures to explain financial performance.The empirical analysis uses the data of 2,398 observations of 240 companies rated by S&P Global Ratings for the period 2009-2013,applying a Generalized Method of Moments(GMM)methodology to estimate the models due to its ability to address potential endogeneity issues.The study considers Return on Assets(ROA)and Tobin’s Q as dependent variables.It incorporates credit ratings(CRWLTA)along with variables such as Total Debt to Total Assets(TDTA),Total Shareholder Return(TSR),EBITDA Interest coverage(EBITDAICOV),Quick Ratio(QR),Altman’s Z-Score(AZS),as well as macroeconomic factors like Gross Domestic Product(GDP)growth,inflation(Consumer Price Index-CPI),and the Federal Reserve Interest Rate(FDRI)as independent variables.The study argues that credit ratings,which incorporate historical data and confidential information about companies’strategies,provide reliable forward-looking creditworthiness assessments to the market.It is supported by specialized rating agencies that employ their methodologies.However,the findings suggested that CRWLTA,had a negative relationship with Q Tobin,although it was not statistically significant,and a negative relationship with ROA that was on the verge of significance. 展开更多
关键词 credit ratings financial performance risk management
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Prediction of film ratings based on domain adaptive transfer learning
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作者 舒展 DUAN Yong 《High Technology Letters》 EI CAS 2023年第1期98-104,共7页
This paper examines the prediction of film ratings.Firstly,in the data feature engineering,feature construction is performed based on the original features of the film dataset.Secondly,the clustering algorithm is util... This paper examines the prediction of film ratings.Firstly,in the data feature engineering,feature construction is performed based on the original features of the film dataset.Secondly,the clustering algorithm is utilized to remove singular film samples,and feature selections are carried out.When solving the problem that film samples of the target domain are unlabelled,it is impossible to train a model and address the inconsistency in the feature dimension for film samples from the source domain.Therefore,the domain adaptive transfer learning model combined with dimensionality reduction algorithms is adopted in this paper.At the same time,in order to reduce the prediction error of models,the stacking ensemble learning model for regression is also used.Finally,through comparative experiments,the effectiveness of the proposed method is verified,which proves to be better predicting film ratings in the target domain. 展开更多
关键词 prediction of film rating domain adaptive transfer component analysis(TCA) correlation alignment(CORAL) stacking
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Aspect Level Songs Rating Based Upon Reviews in English
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作者 Muhammad Aasim Qureshi Muhammad Asif +4 位作者 Saira Anwar Umar Shaukat Atta-ur-Rahman Muhammad Adnan Khan Amir Mosavi 《Computers, Materials & Continua》 SCIE EI 2023年第2期2589-2605,共17页
With the advancements in internet facilities,people are more inclined towards the use of online services.The service providers shelve their items for e-users.These users post their feedbacks,reviews,ratings,etc.after ... With the advancements in internet facilities,people are more inclined towards the use of online services.The service providers shelve their items for e-users.These users post their feedbacks,reviews,ratings,etc.after the use of the item.The enormous increase in these reviews has raised the need for an automated system to analyze these reviews to rate these items.Sentiment Analysis(SA)is a technique that performs such decision analysis.This research targets the ranking and rating through sentiment analysis of these reviews,on different aspects.As a case study,Songs are opted to design and test the decision model.Different aspects of songs namely music,lyrics,song,voice and video are picked.For the reason,reviews of 20 songs are scraped from YouTube,pre-processed and formed a dataset.Different machine learning algorithms—Naïve Bayes(NB),Gradient Boost Tree,Logistic Regression LR,K-Nearest Neighbors(KNN)and Artificial Neural Network(ANN)are applied.ANN performed the best with 74.99%accuracy.Results are validated using K-Fold. 展开更多
关键词 Machine learning natural language processing songs reviews:sentiment analysis songs rating aspect level sentiment analysis reviews analysis text classification MUSIC
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Study of the Effect of Operating Temperatures (1320 K, 1420 K and 1520 K) on the Vacant Sites of TiN Alloy in B2 Structure at 45%, 50% and 55% N by MEAM Method
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作者 Alain S. Dzabana Honguelet Yahnn J. Mighensle Mimboui +1 位作者 Ronolvie Bitho Ondongo Timothée Nsongo 《Advances in Materials Physics and Chemistry》 2023年第7期135-149,共15页
In this work, we have studied the vacancy formation energy of TiN alloy of structure B2 of size 10 × 10 × 10 for nitrogen percentages of 45%, 50% and 55% under the influence of temperature at 1320 K, 1420 K ... In this work, we have studied the vacancy formation energy of TiN alloy of structure B2 of size 10 × 10 × 10 for nitrogen percentages of 45%, 50% and 55% under the influence of temperature at 1320 K, 1420 K and 1520 K using the Modified Embedded Atom Method MEAM under the calculation code LAMMPS version 2020. This study has enabled us to understand the behavior of the TiN alloy under different nitrogen percentages in terms of total energy, vacancy formation energy, crystalline parameter, occupancy rate and order parameter. For total energy, we have shown that as temperature increases, total energy decreases, making it easier to obtain TiN at higher temperatures;reaching the value of -7344.9169 eV for the 55% nitrogen structure for the temperature of 1420 K. For the energy of formation, we have shown that the compounds obtained at 1320 K and 1520 K have a more considerable energy of formation than that obtained at 1420 K. The study of fractions and the order parameter showed us that the structure of TiN with 55% nitrogen is less likely, as the composition obtained is at most 53.35%. 展开更多
关键词 MEAM LAMMPS Code Molecular Dynamics Formation Energy Order Pa-rameter Filling Rate FRACTION Alloy DEFECT Gap VACANCY
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分离禽蛋壳膜粉碎装置刀片的设计与试验 被引量:1
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作者 迟媛 隋昂伯 +1 位作者 穆盛志 迟玉杰 《农机化研究》 北大核心 2024年第8期151-158,共8页
为高效分离回收蛋壳膜,设计了一款采用剪切和碾压的粉碎方式专用于分离禽蛋壳膜的粉碎装置。采用干燥的蛋壳膜进行试验,通过理论分析和预试验确定刀片类型、刀片间隙、转子转速、筛网目数为主要影响因素,根据实际生产情况确定各因素的... 为高效分离回收蛋壳膜,设计了一款采用剪切和碾压的粉碎方式专用于分离禽蛋壳膜的粉碎装置。采用干燥的蛋壳膜进行试验,通过理论分析和预试验确定刀片类型、刀片间隙、转子转速、筛网目数为主要影响因素,根据实际生产情况确定各因素的试验水平,以分离率和损耗率为评价指标进行四因素三水平响应面试验;利用Design-Expert 12.0对试验结果进行响应面分析,研究不同影响因素对评价指标的影响规律。验证试验结果表明:当调整转子转速为1374r/min、安装2目筛网、刀片间隙为1mm的50°剪切式刀片时,分离率为86.72%,损耗率为3.71%,大粒径蛋膜较多。试验装置有效提高了粉碎蛋壳膜后蛋膜的分离效果,降低了损耗率,具有极大的优越性。 展开更多
关键词 禽蛋壳膜 粉碎分离 分离率 损耗率
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我国不同付费模式信用评级校验机制研究 被引量:2
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作者 黄晓薇 安小雪 《北京工商大学学报(社会科学版)》 北大核心 2024年第1期90-103,共14页
我国债券市场刚性兑付被打破后,不断出现高评级债券违约事件。为此,监管部门积极发展多种评级,以期提高债券评级质量。通过理论建模与实证分析,研究了不同付费模式信用评级如何综合发挥校验作用。基于博弈模型的理论分析发现,不同付费... 我国债券市场刚性兑付被打破后,不断出现高评级债券违约事件。为此,监管部门积极发展多种评级,以期提高债券评级质量。通过理论建模与实证分析,研究了不同付费模式信用评级如何综合发挥校验作用。基于博弈模型的理论分析发现,不同付费模式评级发挥校验作用的机制在于投资者的反应:当投资者付费和发行人付费两种模式评级差值增大,投资者不以单一评级结果进行债券定价,而是根据评级差值调整债券价格。基于2011—2020年企业债评级数据的经验证据显示,随着评级差值增大,发行人付费评级机构会降低后续评级,且评级差值对单一信用评级与债券信用利差之间的负向关系具有抑制作用。进一步检验发现,发行人付费评级机构提供的偏正面的私有信息会降低债券信用利差,而以中债资信为代表的投资者付费评级机构提供的私有信息则不会显著影响债券信用利差,均体现出单一评级模式在定价方面的弊端。因此,监管部门应继续鼓励发展投资者付费评级模式,并鼓励机构投资者发展内部评级,以充分发挥多种评级模式的交叉校验作用。 展开更多
关键词 债券市场 付费模式 信用评级 校验机制 评级差值 评级质量
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Strategic Planning for Equitable RWIS Implementation:A Comprehensive Study Incorporating a Multi-variable Semivariogram Model
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作者 Simita Biswa Tae J.Kwon 《Journal of Geographical Research》 2023年第4期54-72,共19页
This paper extends the previously developed method of optimizing Road Weather Information Systems(RWIS)station placement by unveiling a sophisticated multi-variable semivariogram model that concurrently considers mult... This paper extends the previously developed method of optimizing Road Weather Information Systems(RWIS)station placement by unveiling a sophisticated multi-variable semivariogram model that concurrently considers multiple vital road weather variables.Previous research primarily centered on single-variable analysis focusing on road surface temperature(RST).The study bridges this oversight by introducing a framework that integrates multiple critical weather variables into the RWIS location allocation framework.This novel approach ensures balanced and equitable RWIS distribution across zones and aligns the network with areas both prone to traffic accidents and areas of high uncertainty.To demonstrate the effectiveness of this refinement,the authors applied the framework to Maine’s existing RWIS network,conducted a gap analysis through varying planning scenarios and generated optimal solutions using a heuristic optimization algorithm.The analysis identified areas that would benefit most from additional RWIS stations and guided optimal resource utilization across different road types and priority locations.A sensitivity analysis was also performed to evaluate the effect of different weightings for weather and traffic factors on the selection of optimal locations.The location solutions generated have been adopted by MaineDOT for future implementations,attesting to the model’s practicality and signifying an important advancement for more effective management of road weather conditions. 展开更多
关键词 RWIS Location optimization Multi-variable semivariogram HEURISTICS Spatial simulated annealing(SSA) Collision rate(CR)
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不同施氮量对春小麦灌浆速率和产量的影响 被引量:1
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作者 高新 汪烨霖 +8 位作者 朱泰武 李剑峰 王重 时佳 王春生 张宏芝 王立红 樊哲儒 张跃强 《新疆农业科学》 CAS CSCD 北大核心 2024年第2期310-317,共8页
【目的】研究不同施氮量对小麦籽粒灌浆进程的调控效应,分析滴灌条件下春小麦产量的提升潜力,为确定不同品质类型小麦品种适宜施氮量提供理论依据。【方法】以11个新疆审定的春小麦常规品种和1个现阶段正在培育的品系为材料,设置4个施... 【目的】研究不同施氮量对小麦籽粒灌浆进程的调控效应,分析滴灌条件下春小麦产量的提升潜力,为确定不同品质类型小麦品种适宜施氮量提供理论依据。【方法】以11个新疆审定的春小麦常规品种和1个现阶段正在培育的品系为材料,设置4个施氮水平处理,研究施氮量对不同春小麦品种(系)籽粒灌浆特性和产量的影响。【结果】不同施氮水平下小麦籽粒灌浆趋势均呈现为“S”型,随着施氮量的增加,小麦籽粒的干物质积累量达到最高籽粒千粒重后,积累的有效籽粒干物质重不增反降,但下降程度有所减缓。新春6号、新春37号、核春137表现为灌浆强势品种,新春11号、新春21号、新春29号表现为灌浆弱势品种。100 kg/hm^(2)低氮水平下,新春17号和核春615产量达最高水平;200 kg/hm^(2)中氮水平下,新春6号、新春11号、新春26号、新春29号、新春37号、新春39号、核春121和核春514共8个春小麦品种产量达最高水平;300 kg/hm^(2)高氮水平下,核春137和新春21号产量达最高水平。【结论】4个施氮水平下,最大灌浆速率V max与平均灌浆速率Vs均呈极显著正相关,平均灌浆速率Vs与灌浆总天数T均呈负相关。公顷产量Y与千粒重A、最大灌浆速率V max、平均灌浆速率Vs、达到最大灌浆速率所用天数T max、灌浆总天数T均呈正相关。 展开更多
关键词 小麦 氮肥 灌浆速率 产量
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设施生菜光合和蒸腾速率影响因素分析与预测模型构建 被引量:1
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作者 张增林 杨杰 +2 位作者 郭常江 韩文霆 杨振超 《农业机械学报》 EI CAS CSCD 北大核心 2024年第1期339-349,共11页
光合速率及蒸腾速率是植物的2个重要生理指标。在全人工环境下,选取意大利生菜作为对象,设计并开展多环境变量对生菜光合速率及蒸腾速率影响的嵌套实验,得到环境因子对生菜光合速率及蒸腾速率的影响规律,应用神经网络构建生菜幼苗期光... 光合速率及蒸腾速率是植物的2个重要生理指标。在全人工环境下,选取意大利生菜作为对象,设计并开展多环境变量对生菜光合速率及蒸腾速率影响的嵌套实验,得到环境因子对生菜光合速率及蒸腾速率的影响规律,应用神经网络构建生菜幼苗期光合速率及蒸腾速率预测模型。针对幼苗期生菜,选择温度、相对湿度、光子通量密度(Photosynthetic photon flux density, PPFD)及CO_(2)浓度共4个环境影响因素,采用随机森林方法对数据进行相关性分析。结果表明,与蒸腾速率相关性由大到小的因素依次为CO_(2)浓度、温度、相对湿度、PPFD,与光合速率相关性由大到小的因素依次为CO_(2)浓度、PPFD、温度、相对湿度;采用枚举法确定隐藏层节点数和训练函数,通过遗传算法优化BP神经网络的初始权值和阈值,构建GA-BP神经网络生理指标预测模型。应用测试数据对模型进行验证,光合速率及蒸腾速率预测值与实测值的决定系数分别为0.962 12、0.979 44,均方根误差(RMSE)分别为2.983 2μmol/(m^(2)·s)、0.001 435 8 mol/(m^(2)·s),表明GA-BP神经网络在模型精度和迭代次数方面性能显著提高。研究结果可为设施生菜生产环境调控提供有效依据。 展开更多
关键词 设施生菜 光合速率 蒸腾速率 预测模型 相关性分析 GA-BP神经网络
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电力线信道中极化码译码算法的改进
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作者 张京席 鲁越 陈智雄 《电力信息与通信技术》 2024年第5期17-24,共8页
脉冲噪声是影响电力线通信性能的最主要因素。为了提升极化码在电力线信道的性能,文章提出了分段循环冗余校验码辅助串行抵消列表比特翻转(segmented CRC aid SCL-bit flip,SCA-SCL-BF)译码算法,并在加性高斯白噪声(additive white gaus... 脉冲噪声是影响电力线通信性能的最主要因素。为了提升极化码在电力线信道的性能,文章提出了分段循环冗余校验码辅助串行抵消列表比特翻转(segmented CRC aid SCL-bit flip,SCA-SCL-BF)译码算法,并在加性高斯白噪声(additive white gaussian noise,AWGN)信道和电力线信道下进行了仿真。在构造关键集合时引入Rate1子块,避免了全集搜索的复杂度;根据关键集合中比特的位置进行分段,每段翻转一比特,可以实现多比特翻转。仿真结果表明,SCA-SCL-BF算法的性能相较于公开文献中性能在信噪比(signal-to-noiseratios,SNR)大于0dB时有显著提升。该算法对于提升电力线传输性能有重要意义。 展开更多
关键词 电力线通信 MCAN模型 极化码 Rate1子块 分段译码
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基于多维空间的航路利用率 被引量:1
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作者 谢春生 胡泽涛 张兆宁 《科学技术与工程》 北大核心 2024年第7期3004-3009,共6页
航路利用率表征了空域中航路的利用情况,通过计算航路利用率可以实现对空域资源进行更合理、高效的利用。为了更加准确地计算给定时间段内固定航路的利用率,通过构建抽象的三维空间,提出了一种基于多维空间的航路利用率计算方法。在考... 航路利用率表征了空域中航路的利用情况,通过计算航路利用率可以实现对空域资源进行更合理、高效的利用。为了更加准确地计算给定时间段内固定航路的利用率,通过构建抽象的三维空间,提出了一种基于多维空间的航路利用率计算方法。在考虑时间和空间两个角度之间的相互联系有了突破,从时间、航路、高度层三个维度建立航路时空利用率计算模型计算航路时空利用率,结合航路容量利用率,从时间、空间、容量三个角度出发,建立了航路利用率计算模型。最后通过算例分析计算得到某一空域四条航路的利用率。 展开更多
关键词 航路利用率 多维空间 高度层 航路 航路时空利用率 航路容量利用率
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中国式现代化目标下构建新型能源体系之路径思考 被引量:5
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作者 侯梅芳 梁英波 徐鹏 《天然气工业》 EI CAS CSCD 北大核心 2024年第1期177-185,共9页
倡导人与自然和谐共生的中国式现代化,对中国能源领域的高质量可持续发展提出了新要求、新部署,“加快规划建设新型能源体系”势在必行。为了助推中国式现代化目标下新型能源体系的构建,分析了其提出的战略背景,明确了其重要意义,阐述... 倡导人与自然和谐共生的中国式现代化,对中国能源领域的高质量可持续发展提出了新要求、新部署,“加快规划建设新型能源体系”势在必行。为了助推中国式现代化目标下新型能源体系的构建,分析了其提出的战略背景,明确了其重要意义,阐述了其内涵特征,提出了其路径建议。研究结果表明:①新型能源体系是社会主义现代化强国建设的关键抓手,是实现碳达峰碳中和目标以及推进生态文明建设的重要支撑,是国家能源安全和国家竞争力的有力保障;②新型能源体系以促进人与自然和谐共生为根本宗旨,以保证能源安全和经济社会发展稳定为基本前提,具有理念更新、能源结构更新、技术创新、治理创新、产业革新、电力革新等内涵特征;③新型能源体系的构建路径包括加快培育绿色低碳文化、加快推动能源结构转型、加快推动产业结构升级、加快攻关关键核心技术、加快构建体制机制保障等。结论认为,立足我国能源资源禀赋,坚持“先立后破”的方式构建清洁低碳、安全高效的新型能源体系,提高能源自给率,特别是油气自给率,确保能源转型平稳有序、能源保障安全可靠,可以为当前复杂国际形势下的国家能源安全提供强有力的保障。 展开更多
关键词 中国式现代化 新型能源体系 碳达峰碳中和 绿色低碳 能源自给率 油气自给率 “先立后破”
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2021年重庆市宫颈癌发病率、死亡率与生存率分析 被引量:1
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作者 丁贤彬 吕晓燕 +3 位作者 焦艳 高旸 熊娟 许杰 《现代肿瘤医学》 CAS 2024年第4期726-731,共6页
目的:了解2021年重庆市宫颈癌发病率、死亡率与五年生存率,为开展恶性肿瘤防治提供依据。方法:收集整理2021年重庆市新发宫颈癌发病死亡数据,分析2021年重庆市宫颈癌发病率、标化发病率、死亡率、标化死亡率、年龄别发病率与死亡率。中... 目的:了解2021年重庆市宫颈癌发病率、死亡率与五年生存率,为开展恶性肿瘤防治提供依据。方法:收集整理2021年重庆市新发宫颈癌发病死亡数据,分析2021年重庆市宫颈癌发病率、标化发病率、死亡率、标化死亡率、年龄别发病率与死亡率。中国人口标化率采用2000年第五次人口普查标准人口构成进行标化,世界人口标化率采用2000年世界人口构成进行标化。不同性别和地区率的比较采用χ^(2)检验。对2016年新报告的宫颈癌病例进行主动和被动生存随访,采用生存分析寿命表法计算观察生存率,采用乘积极限法(Kaplan-Meier)计算平均生存时间,生存率的比较采用Log Rank of Mantel-Cox进行统计检验。结果:2021年重庆市宫颈癌发病率、中国标化发病率、世界标化发病率分别为21.60/10万、14.64/10万与14.71/10万,宫颈癌发病率农村(23.32/10万)高于城市(17.67/10万)(χ^(2)=6.96,P<0.01)。宫颈癌死亡率、中国标化死亡率、世界标化死亡率分别为5.00/10万、2.79/10万与3.02/10万,宫颈癌死亡率农村(5.65/10万)高于城市(3.53/10万)(χ^(2)=5.42,P=0.02)。2021年重庆市宫颈癌五年生存率为64.32%,城市地区宫颈癌五年生存率(76.35%)高于农村地区(59.79%),差异有统计学意义(χ^(2)=46.65,P<0.01)。结论:重庆市宫颈癌发病率与死亡率高,五年生存率较低,应重视宫颈癌的防治。 展开更多
关键词 宫颈癌 发病率 死亡率 生存率
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高校就业评价的误区与路径重构 被引量:1
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作者 问清泓 黄淑莹 《中国考试》 北大核心 2024年第1期25-33,共9页
学生就业评价是对我国高等院校育人质量的检验与评估,其基本目标和导向是“更加充分更高质量就业”,其中包括就业数量与质量的辩证统一。然而,有些高校就业评价只注重数量而忽略质量,容易陷入“唯就业率”与片面追求落实率的误区。重构... 学生就业评价是对我国高等院校育人质量的检验与评估,其基本目标和导向是“更加充分更高质量就业”,其中包括就业数量与质量的辩证统一。然而,有些高校就业评价只注重数量而忽略质量,容易陷入“唯就业率”与片面追求落实率的误区。重构高校就业评价机制,可以遵循先破后立的原则,摒弃就业率,优化落实率,构建科学与系统的评价指标体系。同时,将实习与就业见习纳入就业评价范畴之中,加强实习质量与就业的关联性评价,从见习岗位数量与质量、见习与就业转换“留用率”上进行评价,从而重构就业评价路径。 展开更多
关键词 就业评价 就业率 落实率 实习 就业见习
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基于数值试验的降雨径流过程对不透水面空间分布的响应分析 被引量:1
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作者 梅超 石虹远 +5 位作者 李瑞栋 李玉龙 刘家宏 栾清华 王浩 王佳 《水资源保护》 EI CSCD 北大核心 2024年第1期86-92,共7页
为解析降雨径流过程对不透水面空间分布的响应关系,构造了一个3 km×3 km的假想试验区域,面向试验区域构建了包含6个不透水率的36种不透水面空间分布,并建立相应的数值试验模型,模拟了重现期分别为2、5、10、20、50、100 a共6种不... 为解析降雨径流过程对不透水面空间分布的响应关系,构造了一个3 km×3 km的假想试验区域,面向试验区域构建了包含6个不透水率的36种不透水面空间分布,并建立相应的数值试验模型,模拟了重现期分别为2、5、10、20、50、100 a共6种不同重现期短历时设计降雨下的降雨径流过程,基于模拟结果对不同不透水面空间分布情景下的降雨径流过程进行了分析。结果表明:在同一不透水率下,不同不透水面空间分布的径流系数差异相对较小,不透水面空间分布对径流特征的影响主要体现在径流峰值和峰现时间上;在同一降雨条件下,不透水率变化是径流过程变化的主导因素,径流系数与不透水率呈线性相关关系,随着不透水率的增加,径流过程线逐渐由“矮胖”变得“尖瘦”。 展开更多
关键词 不透水面 空间分布 不透水率 降雨径流 数值试验
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