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关键词： PT-symmetric quantum mechanics   Photonics   Waveguide arrays  

摘要： Dynamically encircling an exceptional point in non-Hermitian systems has drawn great attention recently, since a nonadiabatic transition process can occur and lead to intriguing phenomena and applications such as the asymmetric switching of modes. While all previous experiments have been restricted to two-state systems, the dynamics in multistate systems where more complex topology can be formed by exceptional points, is still unknown and associated experiments remain elusive. Here, we propose an on-chip photonic system in which an arbitrary number of exceptional points can be encircled dynamically. We reveal in experiment a robust state-switching rule for multistate systems, and extend it to an infinite-period system in which an exceptional line is encircled with outcomes being located at the Brillouin-zone boundary. The proposed versatile platform is expected to reveal more physics related to multiple exceptional points and exceptional lines, and give rise to applications in multistate non-Hermitian systems.

关键词： Dentistry  

摘要： The aim of this article is to outline the potential risks in orthodontic treatment and the general dental practitioner's role in reducing and managing such risks. The success of orthodontic treatment largely depends on patient understanding of the risk/benefit implications of the orthodontic treatment and all of the potential consequences involved in such treatment. A perfect blend of good case selection, sound clinical judgement and, more importantly, a patient's clear understanding of the potential risks involved and the treatment implications help minimise and manage potential hazards that occur during the course of the treatment.

关键词： human resource management of enterprises   information system   reengineering and application   build  

摘要： With the acceleration of economic globalization and the rapid development of modern high technology, the great value of human resources is also reflected. Therefore, establishing a strong platform for human resources management information system through information technology and realizing the combination of information technology and human resources management are beneficial to promoting the further development of enterprise human resources management information system. In this paper, the current situation of enterprise human resources management information system is analyzed. Compared with the traditional human resources information management model, the business process of enterprise human resources management is straightened out and standardized through the actual operation of each process, and the corresponding modules and functions are re-established for each process of enterprise human resources management information system, so as to build a relatively perfect enterprise human resources management information system, which is of great significance for accelerating the development of enterprises and improving economic benefits.

关键词： 公共管理学科   发展背景   特征  

摘要： 公共管理是社会快速发展下诞生的新型学科是一门综合性较强的学科,包含着公共性和管理性.公共管理学科的学习内容和目标在不断地改变,从传统的公共行政学到当前新的公共管理学科以及政策科学发生变化,对当前的政府管理以及研究奠定了良好的基础.本文主要简单介绍公共管理学科历史发展的基本背景,在此基础上指出当前以及国内外公共管理学科发展的特征.

关键词： 营改增   科研经费   高校   税务筹划  

摘要： 近年来,我国高等教育水平不断提升,极大促进了社会的发展。在营改增的税务改革下,高校如何提高资金利用效率,提高科研人员的工作积极性,是高校财务人员面临的挑战。本文首先分析营改增背景下对科研经费管理产生的影响;其次从这些影响中发掘税务管理可能会产生的问题;最后对出现的问题提出提高财务部门自身效率、加强税收筹划、完善合同签订及管理工作、对涉税收入和支出账务处理的改进、加强信息化建设等五点具有针对性的对策和意见,帮助高校更好地管理涉税经费,积极融入国家金融改革的发展战略,促进社会的发展。

关键词： 无实际控制人   中小投资者保护   公司治理  

摘要： 以2003—2019年的中国A股上市公司为样本,研究上市公司无实际控制人情景下的中小投资者保护问题,研究表明,相比上市公司有实际控制人,当上市公司无实际控制人时,这些公司更会通过资金占用与关联交易等方式来掏空上市公司,损害中小投资者利益,该结论在控制内生性后依然成立。进一步研究发现,股权制衡、管理层持股及法律环境和外部审计等能够抑制无实际控制人企业对中小投资者的利益侵害。此外,无实际控制人企业会存在更多的财务违规现象,公司业绩波动性也更大。研究发现有助于监管层加强对无实际控制人公司的监管。

关键词： 科技创新共同体   双循环新发展格局   科创走廊   一带一路   复杂科学管理  

摘要： 运用复杂科学管理的双向循环方法论和升维降维方法论,吸纳复杂系统和谐共生理论方面的最新研究成果,对科技创新共同体进行内涵界定,阐述科技创新共同体的共生效应、超循环效应和演化效应,提出科技创新共同体的条件以及地缘优先、基础优先、风险韧性和分段建设4个原则,提出建设以科创走廊为依托的国内区域科技创新共同体的洋葱模型,描画国内区域科技创新共同体的未来布局对国际科技创新共同体构建的环境进行了分析并提出以"一带一路"为依托的国际科技创新共同体的建设思路和具体举措,提出国内区域科技创新共同体与国际科技创新共同体有效对接的途径。