Search

为了提高室内定位精度,实现三维定位,文章提出了一种基于单个发光二极管（LED）的室内反向定位系统。该定位系统解决了利用多个LED定位时的干扰问题,其将日常所用的白光LED作为光源,既与实际情况相符,又便于将来推广使用。该定位系统根据接收机接收到的光照度来估算距离,以残差平方和最小为目标函数拟合出最佳回归曲线,再利用三边定位原理以及空间几何关系确定接收机坐标。实验结果表明,在实际应用场景中,该定位系统能够实现准确的室内定位服务。

介绍了目前高速长距离光纤通信中常用的电光调制器的原理、结构和应用。目前半导体调制器的研究日趋成熟,性能不断改善。有机聚合物电光调制器被公认为是最具潜力的高速光通信调制器,正成为人们关注的焦点。

为了解决波分复用（WDM）网络中由于流量分布变化而导致网络中预配置P圈保护资源分配不准确的问题,提出了可重构P圈的概念,并建立了一种基于网络性能参数进行重新配置的P圈模型。在OPNET中搭建仿真平台,基于泛欧COST239网络拓扑结构,对提出的模型进行了验证。仿真结果表明,根据网络的变化重新计算优选P圈,可以降低网络的性能抖动,提高网络的保护资源利用率。

自动交换光网络（ASON）控制协议采用通用多协议标签交换（GMPLS）控制协议族,其路由部分主要为开放式最短路径优先（OSPF）协议。文章分析了OSPF协议加密措施存在的安全隐患,并对现有的加密方案进行了改进。针对OSPF协议的安全模式,提出了一种可以应用于ASON中路由技术的新的安全性方案。基于数论算法,实现S盒动态调整,通过动态产生的子密钥,在迭代过程中对分组进行加密。

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry 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 Shipin Kexue/ Food Science is the property of Food Science Editorial Department 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 Frontiers of Computer Science & Technology is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. 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 Automobile Technology is the property of Automobile Technology 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 Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute 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.)

卒中后肢体痉挛是上运动神经元损伤导致高级中枢失去对脊髓牵张反射的抑制，脊髓 反射性增高引起以牵张反射增强为特征的肌肉张力异常。肢体痉挛是卒中后常见并发症之一，严重影 响了卒中患者功能康复。近年来涌现出各类改善卒中后肢体痉挛的治疗方法，但其疗效评价标准不 一，其中以主观性量表评价为主。笔者搜集了近些年国内外卒中后肢体痉挛治疗的临床研究文献，发 现F波、H反射相关参数等客观评价指标被越来越多地与主观评价量表相结合，运用到各类临床研 究的疗效评价中。相对于H反射，F波具有更加灵敏的特点，能更好反映肢体肌张力的变化，常与改良 Ashworth痉挛量表一起作为缺血性卒中后肢体痉挛疗效的评价指标。 Abstract: Spasticity of limbs in post-stroke patients is a common abnormal muscle tone characterized by an enhancement of spinal cord stretch reflex. This is caused by the upper motoneuron injury leading to the loss of spinal stretch reflex inhibition from high-level central nervous system. Limb spasticity can seriously affect the functional rehabilitation of post-stroke patients. In recent years, various anti-spastic therapies emerged, but the evaluation criteria of antispastic effect are different, and these criteria are mainly subjective ones. The objective evaluation indexes such as F wave and H reflection were often used in combination with the subjective evaluation scales to evaluate the anti-spastic effect in recent clinical studies. However, compared to H reflex, F wave is more sensitive and can reflect the changes of limb muscle tone better. Hence, at present the modified Ashworth Scale combined with F wave are often used to evaluate the effect of anti-spastic treatment in post-stroke patients.

Copyright of Journal of Geomechanics is the property of Journal of Geomechanics 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 Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery 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.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy 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 Journal of Zhejiang University (Science Edition) is the property of Journal of Zhejiang University (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 Coal Science & Technology (0253-2336) is the property of Coal 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 South Architecture / Nanfang Jianzhu is the property of South Architecture 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 Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding 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 Automobile Technology & Material is the property of Automobile Technology & Material 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 Shipin Kexue/ Food Science is the property of Food Science Editorial Department 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 Electric Power Engineering Technology is the property of Editorial Department of Electric Power Engineering 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 CT Theory & Applications is the property of Editorial Department of CT Theory & Applications 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 Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute 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 Rural Water & Hydropower is the property of China Rural Water & Hydropower 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 Irrigation & Drainage is the property of Journal of Irrigation & Drainage 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.)

Maintaining the authority and centralized and unified leadership of the CPC Central Committee is a major subject of Marxist party construction. The central authority of Marxist political parties emphasizes the dialectical unity of compulsory power and conscious obedience, leading core and leading collective, centralization and democracy. The central authority is of great significance to maintaining the cohesion of Marxist party organization, the efficiency of policy implementation and the strategic choice of the party at the important moment. Scientific theoretical guidance, the authority of the leadership core, democratic centralism, party discipline and system construction are important mechanisms to safeguard the central authority of Marxist political parties. Socialism with Chinese characteristics has entered a new era, the "two establishments" should be put into practice, and the "core consciousness" should be strengthened. Under the leadership of political construction and on the basis of ideological construction, we should constantly improve the construction of democratic centralism and institutional system, and transform the "two establishments" into the political consciousness, ideological consciousness and action ability of "two maintenance". [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department 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 Geomechanics is the property of Journal of Geomechanics 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 Food Research & Development is the property of Food Research & Development Editorial Department 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 South Architecture / Nanfang Jianzhu is the property of South Architecture 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 Aeronautical Materials is the property of Editorial Board of Journal of Aeronautical Materials 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 Frontiers of Computer Science & Technology is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. 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.)

This study was aimed at understanding the effects of nitrogen gradient loading on the growth and chlorophyll fluorescence characteristics of Phoebe bournei seedlings through a simulated experiment on two-year-old P. bournei seedlings under seven nitrogen levels, N0 (0 g·m-2·a-1), N1 (5 g·m-2·a-1), N2 (10 g·m-2·a-1), N3 (15 g·m-2·a-1), N4 (20 g·m-2·a-1), N5 (25 g·m-2·a-1), and N6 (30 g·m-2·a-1) after 6 months of planting. The results showed that with an increase in nitrogen concentration, seedling height, ground diameter, and whole plant biomass showed an increase-decrease-increase pattern. Seedling height reached the maximum at N1 (142.41 cm), ground diameter and whole plant biomass reached the maximum at N2 (15.31 mm and 192.22 g, respectively), and these growth indices increased by 48.33%, 28.55%, and 114.58%, respectively, compared with the control group. Different nitrogen gradient loading treatments promoted an increase in total chlorophyll content in the leaves of P. bournei seedlings; the total chlorophyll content in leaves of the N2 and N3 groups was significantly higher and that of the N6 group was significantly lower than in the leaves of the N0 group (P < 0.05). With an increase in nitrogen intensity, the maximum photochemical efficiency (Fv/Fm), potential photochemical activity (Fv/Fo), and actual photochemical efficiency (Yield) of P. bournei seedlings showed an increase-decrease-increase trend, and the photochemical quenching coefficient (qP) and nonphotochemical quenching coefficient (qN) showed a decrease-increase-decrease trend. From the perspective of chlorophyll fluorescence parameters, N3 and N4 were the optimum concentration ranges of N For P. bournei seedlings; the photosynthetic efficiency of P. bournei seedlings could be significantly improved by an appropriate increase in nitrogen supply. [ABSTRACT FROM AUTHOR]

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 Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery 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.)

Coalbed methane high efficiency production from broken soft and low permeable coal seams has been being a technical bottleneck of restricting coalbed methane industrialization development and coal mine gas control for many years.This paper has investigated the No.8 broken soft and low permeable coal seam in Lulling coal mine of Huaibei mining area in Anhui Province,China.Site investigation,sampling and testing,theoretical analysis,hydraulic fracture physical and numerical simulation have been performed.As a result,a new model of coalbed methane high efficiency production from broken soft and low permeable coal seam by roof strata-in horizontal well and staged hydraulic fracture has been presented,the hydraulic fracture extension and control mechanism under this model have been revealed,and the main technological processes of the model implementation have been given.The results show that the roof strata are relatively brittle and have high propagation pressures,while the broken soft coal seam is relatively plastic and has a low propagation pressure.When case perforation and hydraulic fracture are performed in horizontal well of the roof strata,the hydraulic fractures in roof strata,on the vertical,extend downward and penetrate the broken soft coal seam.At the same time,the hydraulic fractures also get rapid horizontal extension,and the traction engendered by this rapid horizontal extension rips the coal seam to form long hydraulic fractures in the coal seam.Numerical simulation results show that the hydraulic fracture length formed in the broken soft and low permeable coal seam when fracturing in roof strata is long as 6.7 times as that when fracturing directly in the coal seam.Those hydraulic fractures formed in the roof strata and the broken soft coal seam are filled with sand proppant in follow-up adding-sand fracturing,and come into being a coalbed methane migration pathway from the underlying coal seam to the roof strata-in horizontal well.It can be seen that broken soft coal seam can get a good fracturing stimulation effect in this new model.The results of this study are applied to the coalbed methane development demonstration project by roof strata-in horizontal well and staged hydraulic fracture in Luling coal mine of Huaibei mining area in Anhui province,China and have obtained a good gas production effect.The average daily gas production rate of the single coalbed methane horizontal well was respectively 10 358 m3,9 039 m3,7 921 m3 in three,six and twelve consecutive months.As of November,16,2017,this horizontal well already produced 5 million cubic meters of coalbed methane gas,and its daily gas production rate was still over 3 200 m3.This has created a new record of gas production of a single coalbed methane horizontal well from broken soft and low permeable coal seam in China. [ABSTRACT FROM AUTHOR]