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泊松点过程（PPP）由于其理论可分析性和随机性而被广泛用于无线网络建模及分析,但实际基站部署并不是完全随机的,针对基站在空间上存在互斥的情况,文章采用泊松硬核过程（PHCP）建模异构蜂窝网络（HCN）,选择基于最大信干比（SIR）准则的基站接入方案,采用每层泊松SIR近似方法推导出了两层基于PHCP的HCN的近似覆盖率。仿真结果表明,该方法所产生的近似覆盖率为实际覆盖率的渐近下边界,并且PHCP网络的覆盖率优于PPP网络覆盖率,更适应于具有互斥性的实际基站部署。

文章仿真研究了两种改进型光双二进制调制格式。首先对比分析了产生两种改进型光双二进制调制格式的发射机结构及两种调制格式的码型和频谱特性,随后进行了系统的传输性能仿真。仿真结果表明:当残留色散较大时,改进Ⅱ型光双二进制调制格式性能较为优异;而在-13.22.8dBm入纤光功率范围内,与改进Ⅱ型光双二进制和NRZ（非归零）码调制格式相比,改进Ⅰ型光双二进制的Q值最高,抗非线性效应能力最强。

鉴于单通道解调系统一次可检测的光栅波长数目有限,同时为兼顾FBG（光纤布拉格光栅）解调系统与上位机通信的稳定性与高速性,结合波分复用与空分复用技术,研制了多通道、多通信端口的FBG解调系统。通过控制16路光开关的光路切换,可实现对16通道FBG传感网的空分复用,对各通道传感器中心波长进行解调。测试结果表明,解调系统中心波长分辨率为1pm,一次采集光栅波长信息的时间为620ms,16个光通道的FBG传感信息更新最短时间不大于10s,可对约200只光纤光栅传感器进行有效监测。

Copyright of Journal of Academic Library & Information Science is the property of Anhui University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South-Central Minzu University (Natural Science Edition) is the property of Journal of South-Central Minzu University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Condiment is the property of China Condiment and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guihaia is the property of Guihaia Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this experiment was to study the effects of high proportion plant protein diet on the growth performance, digestive enzyme activity, liver function, and serum biochemical indices of Mylopharyngodon piceus. In the experiment, 0, 5%, 10%, 15%, and 20% fish meal protein were replaced by soybean meal (FM20, FM15, FM10, FM5, and SBM groups, respectively). A total of 800 Mylopharyngodon piceus were randomly divided into five groups with four replicates per group and 40 fish per replicate. The test period was 56 days. The results showed that the weight gain rate and specific growth rate in SBM group were significantly lower than those in FM20 group (P<0.05), and the viscerosomatic index and hepatosomatic index were significantly lower than those in FM20 group, FM15 group, and FM10 group (P<0.05). Hepatopancreas trypsin activity was the highest in SBM group, and enteric trypsin activity was the highest in FM20 group. The changes of trypsin and pepsin activity in different tissues were similar, and enteric amylase activity was higher than hepatopancreas, while lipase activity was lower than hepatopancreas. The activities of glutamic oxalic transaminase and glutamic pyruvic transaminase in serum and liver of SBM group were significantly higher than those in other groups (P<0.05). The study shows that the use of appropriate plant protein in feed has no negative effects on the growth, digestion, liver function and biochemical indices of Mylopharyngodon piceus, and the minimum amount of fish meal is recommended to be 5%. [ABSTRACT FROM AUTHOR]

The basic characteristics of hcterotrophic-sulfur autotrophic denitrification technology were introduced. Traditional heterotrophic denitrification has high operating costs and high sludge production, while sulfur autotrophic denitrification has disadvantages sueh as low denitrification efficiency and alkalinity consumption, which can be complemented by coupling the two processes. Heterotrophic-sulfur autotrophic denitrification is one of the most promising and economical processes for treating low C/N ratio wastewater, which has the advantages of low cost, low SO4²: production, pH stabilisation, and high efficiency of den 让 rification, etc. The synergistic mechanism, microbial community characteristics, and influencing factors were elaborated, and the practical application of this process in urban tailwater, groundwater, and other wastewaters with low C/N ratio was illustrated. At the same time, the existing problems at this stage were summarised and the future research directions were outlook ed to provide theoretical reference for the promotion and practical application of this technology. [ABSTRACT FROM AUTHOR]

Copyright of Tianjin Medical Journal is the property of Tianjin Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Southwest China Journal of Agricultural Sciences is the property of Editorial Department of Southwest China Journal of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Scientifically adjusting forest stand structure emerges as a vital approach to addressing soil degradation in plantation forests within urban green areas. In order to provide a theoretical basis for the rational operation of urban green space, in this study, artificial pure forests of Pinus tabulaeformis, Ulmus pumila, and Robinia pseudoacacia in the forest park of Taiyuan city, Shanxi province were selected. The 20 m×20 m sample plots were established, and soil samples were collected evenly at 5-meter intervals. The stand structure parameters including the number of trees and the average DBH(Diameter at Breast Height) of adjacent trees at various radii from the soil sampling point were calculated based on the positioning of standing trees and the inspection of each tree's base. Pearson's correlation and partial least squares regression analysis were employed to explore the effects of stand structure factors on soil physical properties. The results showed that disparities existed in soil physical properties among different stands. The soil bulk density under Ulmus pumila forests was significantly lower than that under Pinus tabulaeformis and Robinia pseudoacacia forests, while soil water content, capillary water holding capacity, capillary porosity, and saturated water holding capacity in the soil were higher than those under Pinus tabulaeformis and Robinia pseudoacacia forests. Correlation coefficients between stand structure factors and soil physical properties peaked at scales approximating the mean size of standing tree crowns. By double verification of the the Pearson correlation analysis and partial least squares regression analysis, Ulmus pumila forest height had a very high positive correlation with soil saturated water holding capacity, capillary water holding capacity, and water content, so Ulmus pumila forest had superior performance in improving soil physical properties compared to the other two species. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Kunming Medical University / Kunming Yike Daxue Xuebao is the property of Kunming Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Tropical Medicine is the property of China Tropical Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geography Teaching is the property of Geography Teaching Editorial Office, East China Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In response to the problem of heavy workload and difficulty in improving the generalization ability of feature selection in building load prediction models, a method based on extreme gradient boosting(XGBoost)-neural network for building load feature selection and prediction was proposed. The XGBoost algorithm was used to train the filtered data, and the optimal feature subset was determined based on the mean absolute percentage error(MAPE) to improve the model accuracy and generalization ability. The Bayesian regularization algorithm was used to train the feedforward neural network to reduce network structure complexity during training optimization and prevent network overfitting, thereby further improving its generalization ability. Experimental results of load prediction for a commercial building show that the mean squared error(MSE) of the model is reduced by 43. 29% after feature selection compared to before, effectively improving the model prediction accuracy. The neural network is trained using both Bayesian regularization and Levenberg-Marquardt(L-M) algorithms, with the former achieving an average reduction of 87. 08% and 85. 33% in root mean squared error (RMSE) and MAPE after 5 experiments, respectively, leading to effective improvement of the prediction model's generalization ability. [ABSTRACT FROM AUTHOR]

Copyright of World Regional Studies is the property of World Regional Studies Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Chemical Industry is the property of Shaanxi Research Design Insitute of Petroleum & Chemical Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The pattern of major-country relations is an issue of vital importance in the current evolving international landscape. General Secretary Xi Jinping pays close attention to major-country relations, and keeps pace with the times to develop and improve relevant theories, thus creating a new pattern of major-country relations with a clear direction. In the face of fundamental differences in principle and intense struggles between the antihegemony forces and those aiming to preserve it in major-country relations, China has taken the initiative to build an overall stable framework of major-country relations with a strong sense of responsibility, and has been promoting the construction of relevant systems and mechanisms in a multilateral approach. Guided by Xi Jinping Thought on Diplomacy, the Chinese concepts and practices in planning and building a new pattern of major-country relations are providing the international community with new thinking, directions and choices due to their advanced nature, feasibility and demonstration effects. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At present, the application of bottom-dipping radar is more and more extensive, but the information interpretation of bottom-dipping radar profile is lack of systematic standard. The image characteristics of forward modeling of six typical underground target models: horizontal layered target, circular target, rectangular target, underground pipeline, local aquifer, and petroleum pollutants were discussed. The two-dimensional finite-difference time-domain method was used to construct the forward modeling model of six typical underground targets in the contaminated site, and the radar profile of the typical underground targets was obtained. The image recognition characteristics of each typical target in the forward simulation profile were further summarized, and the formation mechanism of clutter such as multiple waves and diffraction waves in the radar detection process was analyzed. Finally, the accuracy of ground penetrating radar graphic feature analysis was verified by drilling data of petroleum hydrocarbon polluted site. The research results provide a theoretical basis for the interpretation of reflected signals of ground penetrating radar and the identification of underground targets in practical work. [ABSTRACT FROM AUTHOR]

Copyright of Feed Research is the property of Editorial Board of Feed Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The high-quality development of animal husbandry is necessary support to promote rural revitalization, and also key to building Chinese path to modernization. From perspective of connotation and era positioning, animal husbandry refers to future development of animal husbandry towards ecology, safety, and other aspects to achieve highquality and efficient development, comprehensively improve quality and quantity of social livestock and poultry product supply. Facing Chinese path to modernization, high-quality development of China's animal husbandry not only conforms to goal orientation of ecological and open cooperation in new era, but also follows Chinese law of economic and industrial layout. Therefore, it is proposed to consolidate the foundation and accelerate construction of modern livestock and poultry breeding and breeding industry. Improve security and establish an animal epidemic prevention system. Suggestions on strengthening competition and improving animal husbandry policies and measures to better play the supporting role of high-quality development of animal husbandry in process of Chinese path to modernization. [ABSTRACT FROM AUTHOR]

牙周病是口腔疾病中导致失牙率变高的慢性炎症性疾病, 多酚化合物在牙周病的研究中表现出抗牙周致 病菌的能力, 并可从抗炎、抗氧化多种途径缓解已发生的牙周炎症, 对缺损的牙周组织具有一定的修复作用。目前 研究较多的多酚化合物有槲皮素、花青素、淫羊藿苷、白藜芦醇和姜黄素等, 具有突出的抗炎抗氧化能力及促组织修 复能力, 对防治牙周炎有较好的效果。 [ABSTRACT FROM AUTHOR]

【Objective】To compare the flavonoids content in different parts of Epimedii Folium from Hanzhong City, Shaanxi Province, in order to provide theoretical basis for quality control of Epimedii Folium in the region. 【Methods】The above-ground and underground parts of 17 batches of Epimedii Folium plants were collected from the nine counties and two districts in Hanzhong City and divided into four parts:roots, stems, petioles, and leaves. High performance liquid chromatography (HPLC) was used to determine the six flavonoids of epimedin A1, epimedin A, epimedin B, epimedin C, icariin, and baohuoside Ⅰ. The content differences of Epimedii Folium in the four parts were detected and analyzed. The Epimedii Folium characteristic fingerprints of all the samples were constructed by HPLC, and the common peaks were determined and identified by the similarity evaluation system of traditional Chinese medicine fingerprints. Finally, HPLC fingerprints of the 17 batches of samples were drawn. 【Results】The contents of six components in Epimedii Folium leaves were clearly higher than that of petiole and stem. The six components in the root differed greatly with the content of epimedin C ranging from 0.536% to 4.712%. The total content of the six components in roots, stems, petioles and leaves were 0.616%-5.141%, 0.006%-0.136%, 0.007%-0.271%, and 0.588%-5.100%, respectively. Six common peaks of epimedin A1, epimedin A, epimedin B, epimedin C, icariin, and baohuoside Ⅰ in the 17 batches of samples were identified by Chinese medicine fingerprints, with similarities of roots, stems, petioles and leaves at 0.962-1.000, 0.791-0.990, 0.728-0.996, and 0.629-0.995, respectively.【Conclusion】The quality difference of roots, stems, petioles and leaves of Epimedii Folium from Hanzhong was determined based on multi-component content test.The HPLC fingerprint of Epimedii Folium from Hanzhong was established. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Regional habitat quality is an important reflection of ecosystem service functions and ecosystem health. It is important to clarify the gain and loss of habitat quality in the Gansu-Qinghai section of the Yellow River basin under different terrain gradients, as this is of great significance to the“win-win”policy of economic development and ecological protection in the region. In this study, the InVEST model was used to evaluate temporal and spatial changes in habitat quality in the Gansu-Qinghai section of the Yellow River basin in 1990, 2000, 2010, and 2020, as well as the gain and loss of habitat quality under different topographic gradients. The results showed that, in the past 30 years, the annual average habitat quality in the Gansu-Qinghai section of the Yellow River basin was 0.775, 0.774, 0.774, and 0.778, showing a slight decline and then a significant upward trend. Spatially, it showed a trend of strengthening from east to west and weakening in the middle, and the area with improvement was greater than the area with decreased quality. In the past 30 years, the regional average annual habitat degradation degrees were 0.015 14, 0.015 23, 0.015 24, and 0.014 78, showing a slight upward and then a significant downward trend. Spatially, the deteriorated habitat area was larger than the improved habitat area, and the deteriorated areas were concentrated in Gansu Province. The habitat quality in the Gansu-Qinghai section of the Yellow River basin is the worst when the terrain gradient is of the lowest grade（gradeⅠ）and the best when the topographic gradient is of the highest grade（grade Ⅴ）. Except for the elevation, the habitat quality in the Gansu-Qinghai section of the Yellow River basin has the largest improvement when the topographic gradient is grade Ⅰ, the loss is the largest when the gradient is grade Ⅴ, and it is completely degraded when the gradient is grade Ⅴ. Temporal and spatial characteristics of habitat quality and topographic gradient effects can provide a scientific basis for policy formulation and implementation of ecological restoration projects in the Gansu-Qinghai section of the Yellow River basin. [ABSTRACT FROM AUTHOR]

Copyright of Drilling Fluid & Completion Fluid is the property of Drilling Fluid & Completion Fluid Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)