The interpenetrating network structure provides an interesting avenue to novel materials. Locally resonant phononic crystal (LRPC) exhibits excellent sound attenuation performance based on the periodical arrangement...The interpenetrating network structure provides an interesting avenue to novel materials. Locally resonant phononic crystal (LRPC) exhibits excellent sound attenuation performance based on the periodical arrangement of sound wave scatters. Combining the LRPC concept and interpenetrating network glassy structure, this paper has developed a new material which can achieve a wide band underwater strong acoustic absorption. Underwater absorption coefficients of different samples were measured by the pulse tube. Measurement results show that the new material possesses excellent underwater acoustic effects in a wide frequency range.Moreover, in order to investigate impacts of locally resonant units,some defects are introduced into the sample. The experimental result and the theoretical calculation both show that locally resonant units being connected to a network structure play an important role in achieving a wide band strong acoustic absorption.展开更多
The extensive research on public ethics in the local administration is more than necessary. This paper identifies the basic values of and the challenges to Macedonian Legal System in this area, and explains the key et...The extensive research on public ethics in the local administration is more than necessary. This paper identifies the basic values of and the challenges to Macedonian Legal System in this area, and explains the key ethical aspects, which should be implemented in practice by civil servants, who increasingly have to learn how to perform in accordance with ethical values. In this paper I will analyze the ethical values of civil servants laid down by the Organization for Economic Co-operation and Development (OECD) and the Civil Servants Agency in Macedonia, upon which the ethical principles for civil servants in the local administration units are intended to be set. This paper deals with the ethics of civil servants, assessment of best practices, and evaluation of positive and negative indicators. The paper concludes with a few recommendations for the next steps in this process; and some criteria for the consideration of future developments are suggested.展开更多
Cross-regional locality research reflects the influences of natural environment and the human activities due to the abundant land types and the multiple landscape combinations in related regions. The Chinese farming-p...Cross-regional locality research reflects the influences of natural environment and the human activities due to the abundant land types and the multiple landscape combinations in related regions. The Chinese farming-pastoral ecotone is a typical large-scale region but few studies were conducted. This research contributed to the understanding of cross-regional locality of the Chinese farming-pastoral ecotone from different scales, including national, sectional, and provincial administrative units by utilizing geotagged photos(GTPs) obtained from the Panoramio website. The major results were as follows:(1) the locality elements of the Chinese farming-pastoral ecotone included 52 free nodes classified into 8 types of scene attributes;(2) there were huge differences between locality elements of different regions, and there was a negative correlation between the similarity degree of elements of different provinces and their spatial distances;(3) the Chinese farming-pastoral ecotone could be divided into the northern, central and southern sections, whose localities had differences in element constitution, association structure and the strength of elements, system stability and the anti-interference capability; and(4) the evolution of the localities of the northern and central sections was mainly influenced by human activities, while the locality of southern section retained more natural features. On a theoretical level, this research aimed to establish the research methodology of locality from the perspective of open data on the web with strong operability and replicability. On a practical level, this research could enrich the structuring recognition of the locality of the Chinese farming-pastoral ecotone and the comprehension of its dynamic mechanism. The results provide a reference for locality differentiation protection and the development of a cross-regional scale.展开更多
The first domestically-integrated large-scale air separation unit (ASU) with a capacity of 60 000 m^3/h was successfully built and put into operation at Baosteel. Compared with the electrical design of the imported ...The first domestically-integrated large-scale air separation unit (ASU) with a capacity of 60 000 m^3/h was successfully built and put into operation at Baosteel. Compared with the electrical design of the imported equipment of the same type,this ASU has an electrical protection interlink that is independent from the distribution control system (DCS). With the design idea of simplicity, the ASU features a simplified configuration and an audio alarm system for electrical failures. It helps reduce the failure rate of the electrical equipment and detect failures quickly and accurately. It will effectively enhance safe and stabilized production. The ASU can not only reduce the cost of investment, but also ensure a smooth and stable running of the whole electrical equipment. This study focuses on the experience and understanding of the unit design and commissioning.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 10832011)the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KJCX2-YW-L08)
文摘The interpenetrating network structure provides an interesting avenue to novel materials. Locally resonant phononic crystal (LRPC) exhibits excellent sound attenuation performance based on the periodical arrangement of sound wave scatters. Combining the LRPC concept and interpenetrating network glassy structure, this paper has developed a new material which can achieve a wide band underwater strong acoustic absorption. Underwater absorption coefficients of different samples were measured by the pulse tube. Measurement results show that the new material possesses excellent underwater acoustic effects in a wide frequency range.Moreover, in order to investigate impacts of locally resonant units,some defects are introduced into the sample. The experimental result and the theoretical calculation both show that locally resonant units being connected to a network structure play an important role in achieving a wide band strong acoustic absorption.
文摘The extensive research on public ethics in the local administration is more than necessary. This paper identifies the basic values of and the challenges to Macedonian Legal System in this area, and explains the key ethical aspects, which should be implemented in practice by civil servants, who increasingly have to learn how to perform in accordance with ethical values. In this paper I will analyze the ethical values of civil servants laid down by the Organization for Economic Co-operation and Development (OECD) and the Civil Servants Agency in Macedonia, upon which the ethical principles for civil servants in the local administration units are intended to be set. This paper deals with the ethics of civil servants, assessment of best practices, and evaluation of positive and negative indicators. The paper concludes with a few recommendations for the next steps in this process; and some criteria for the consideration of future developments are suggested.
文摘为提高回环检测的精度,同时满足实时性的需求,提出了一种多信息作用下的激光回环检测算法。首先,利用惯性测量单元(inertial measurement unit,IMU)信息得到每个点云帧之间的相对运动;然后,提取点云中的高度信息、强度信息以及数量信息并归一化处理;在上下文扫描(scan context,SC)描述符的基础上,定义了融合IMU与点云信息的上下文扫描(IMU and point scan context,IPSC)描述符以及对应的相似度函数;最后,引入改进的正态分布变换(normal distributions transform,NDT)算法进行综合相似度判断。针对所提出的算法在多个数据集上进行实验,结果表明,该算法在回环检测时具有较高的精度,能够在不同场景下进行识别,同时满足了系统的实时性要求,为激光回环检测提供了一种新的方法。
基金supported by the Sino-German Center (the National Natural Science Foundation of China and the German Science Foundation GZ1201)the Postgraduate Courses Project of Peking University (2014-40)
文摘Cross-regional locality research reflects the influences of natural environment and the human activities due to the abundant land types and the multiple landscape combinations in related regions. The Chinese farming-pastoral ecotone is a typical large-scale region but few studies were conducted. This research contributed to the understanding of cross-regional locality of the Chinese farming-pastoral ecotone from different scales, including national, sectional, and provincial administrative units by utilizing geotagged photos(GTPs) obtained from the Panoramio website. The major results were as follows:(1) the locality elements of the Chinese farming-pastoral ecotone included 52 free nodes classified into 8 types of scene attributes;(2) there were huge differences between locality elements of different regions, and there was a negative correlation between the similarity degree of elements of different provinces and their spatial distances;(3) the Chinese farming-pastoral ecotone could be divided into the northern, central and southern sections, whose localities had differences in element constitution, association structure and the strength of elements, system stability and the anti-interference capability; and(4) the evolution of the localities of the northern and central sections was mainly influenced by human activities, while the locality of southern section retained more natural features. On a theoretical level, this research aimed to establish the research methodology of locality from the perspective of open data on the web with strong operability and replicability. On a practical level, this research could enrich the structuring recognition of the locality of the Chinese farming-pastoral ecotone and the comprehension of its dynamic mechanism. The results provide a reference for locality differentiation protection and the development of a cross-regional scale.
文摘The first domestically-integrated large-scale air separation unit (ASU) with a capacity of 60 000 m^3/h was successfully built and put into operation at Baosteel. Compared with the electrical design of the imported equipment of the same type,this ASU has an electrical protection interlink that is independent from the distribution control system (DCS). With the design idea of simplicity, the ASU features a simplified configuration and an audio alarm system for electrical failures. It helps reduce the failure rate of the electrical equipment and detect failures quickly and accurately. It will effectively enhance safe and stabilized production. The ASU can not only reduce the cost of investment, but also ensure a smooth and stable running of the whole electrical equipment. This study focuses on the experience and understanding of the unit design and commissioning.