Borders and Possibilities of Foreign Policy of the Small State on the Example of Kyrgyzstan

In this article is shown all the process which is happening at the moment in the globe. How big countries may influence to the small countries such as Kyrgyzstan. Some approaches that are used for achieving results. Also were taken into account researches of some scientists. Kyrgyzstan is young, small independent country with democratic ideas for running country. The research focus on the whole situation in the country and in the globe, trends. The research methods used from the famous world scientists their findings, participation at the international conferences dedicated to the international diplomacy and etc. The main conclusions small independent country has to follow world trends and collaborate mutually with all countries.

The Role of Small States in Power Contestations in the Horn of Africa Case Study of Djibouti

Djibouti,situated in the Horn of Africa,is one of the smallest coun-tries on the African continent.Arid,with scant natural resources and a high level of poverty,the country has assumed a position of strategic importance in the great power contestations of the twenty-first century owing to its geographical location.Djibouti is located close to the Strait of Bab-el-Mandeb which connects the Gulf of Aden to the Red Sea and is also one of the seven choke points that are crucial to international maritime security and coun-tering cross-border terrorism.Its geographic proximity to the oil-rich Arabian Peninsula and the important shipping lane of the Gulf of Aden makes this small state a role player in great and middle-power rivalries.Host to military bases of China,the USA,Japan,France,Italy,Germany and the United Kingdom,Djibouti is also in talks with Saudi Arabia.This paper will examine the behaviour of a small state like Djibouti against the backdrop of power contestations in the geopolitically sensitive Horn of Africa.Contrary to the popular belief that small states are often com-pelled to bandwagon with the big states,the paper will attempt to make the case that states,albeit small,have agency and tools at their disposal to navigate their course through complex geopo-litical quagmires.IR theories of status-seeking and shelter will be applied to study the case of Djibouti in the context of power contestations.

The Multipolar World and Small States:Emerging Perspectives in India-Kuwait Strategic Partnerships

In the twenty-first Century,small state partnerships are being realigned in the multipolar world.Addressing security concerns of small states,this paper reviews the prospects of strategic partnerships between small states and emerging powers.Contextualising from the historical relations between India and Kuwait,the paper analyses the dynamics of‘soft power’balancing within areas of mutual convergence.Further,the paper presents a future trajectory for small state partnerships with rising powers in an era of geo-economic interdependence.

Weak wide-band signal detection method based on small-scale periodic state of Duffing oscillator

The conventional Duffing oscillator weak signal detection method, which is based on a strong reference signal, has inherent deficiencies. To address these issues, the characteristics of the Duffing oscillator＇s phase trajectory in a small- scale periodic state are analyzed by introducing the theory of stopping oscillation system. Based on this approach, a novel Duffing oscillator weak wide-band signal detection method is proposed. In this novel method, the reference signal is discarded, and the to-be-detected signal is directly used as a driving force. By calculating the cosine function of a phase space angle, a single Duffing oscillator can be used for weak wide-band signal detection instead of an array of uncoupled Duffing oscillators. Simulation results indicate that, compared with the conventional Duffing oscillator detection method, this approach performs better in frequency detection intervals, and reduces the signal-to-noise ratio detection threshold, while improving the real-time performance of the system.

Fuzzy State Comprehensive Evaluation of Living Basis for Small Businesses

The problem of comprehensive evaluation of liying basis for small businesses is discussed, based on fuzziness of index, a corresponding fuzzy state comprehensive evaluation method is presented; the good results that is,the evaluation of living basis for small business are illustrated by a simulated example.

基于谐波状态空间理论的12脉动换流站阻抗建模

为分析谐波对电网换相型换流器高压直流输电系统(line commutated converter based high voltage direct current,LCC-HVDC)稳定性的影响,亟需建立一个考虑谐波耦合效应的LCC-HVDC精确模型。基于谐波状态空间(harmonic state space,HSS)理论,考虑频率耦合效应和控制系统建立了12脉动LCC的阻抗模型,所建交直流谐波阻抗模型能在更宽的频带与扫频结果吻合。最后通过PSCAD电磁暂态仿真结果与HSS阻抗模型计算结果对比,验证了所提出的LCC-HSS阻抗模型的正确性。LCC-HSS阻抗建模方法提高了对LCC换流站进行数学建模的精确性,且可以适应多种模式下LCC换流站阻抗建模,为LCC系统稳定性分析及参数优化提供了较为精确的模型。

小样本下基于改进度量学习的轨面状态识别

为解决小样本下轨面状态识别过程中存在的关键特征信息提取不充分、区分度信息易丢失的问题,提出一种基于改进度量学习的轨面状态识别方法。该方法在特征提取网络部分引入金字塔拆分注意力机制,实现特征图空间信息多尺度提取、跨维度通道注意力与空间注意力特征交互,以解决轨面状态样本少导致的关键特征信息提取不充分的问题。利用深度局部拼接符对查询集与各类支撑集特征图进行局部特征两两拼接,代替传统度量学习的全局特征拼接,筛选背景等干扰信息,较大程度地保留有显著区分度的特征信息。在自建小样本轨面状态数据集上进行性能验证,并与常规小样本学习方法进行对比实验,实验结果表明,本文方法能够有效识别轨面状态,识别准确率、精度、召回率、F1值分别达到97.96%、98.61%、98.07%、98.34%,相比于性能较好的小样本学习方法 DN4网络,各项指标分别提升了5.75个百分点、5.83个百分点、5.95个百分点、5.89个百分点。

考虑交直流谐波耦合的并网逆变器建模与分析

可再生能源的大规模开发利用使得逆变器在电网中的比例越来越高,逆变器与电网间谐波交互作用也愈加频繁和复杂。针对传统的建模方法无法体现逆变器与电网间谐波交互耦合的问题,文中基于谐波状态空间(HSS)理论对三相并网逆变器进行建模,该模型将交直流侧的多个频次谐波考虑在内,具有较高的精度。基于HSS模型推导出输入到输出的谐波传递函数矩阵,建立逆变器交直流谐波耦合导纳幅值图,探究交直流谐波耦合关系。然后,提出了一种适用于闭环控制系统的三相并网逆变器小信号HSS建模方法,通过计算特征值对系统稳定性进行评估以及对振荡频率进行预测。最后与MATLAB/Simulink仿真结果进行对比,验证了所建立HSS模型的准确性和系统稳定性分析的正确性。

三相电压型VIENNA整流器建模及稳定性分析

基于电动汽车直流充电桩的VIENNA型前级整流电路,提出采用小信号方法对VIENNA整流器进行建模。该方法首先通过采用局部线性化技术和状态空间平均法推导dq0坐标系下VIENNA整流器的数学模型,得出相关传递函数矩阵,即VIENNA整流器小信号线性化模型,进而用于控制器的设计;然后,采用频域法分别对电压环、电流环进行设计,利用频域法及根轨迹曲线详细分析各项参数对系统的影响,并利用曲线拟合的方式给出了系统稳定域随各项参数变化的曲线;最后,在实验中验证所提方法的正确性。

融合相机和激光雷达的小天体运动状态估计方法

针对单一视觉传感器难以实现小天体运动状态估计的问题,提出了一种融合相机和激光雷达的小天体运动状态估计方法。首先,建立融合相机和激光雷达测量模型,通过跟踪带有深度信息的图像特征点,利用扩展卡尔曼滤波器估计小天体的自旋角速度、自旋轴方向、位置和速度;其次,设计了特征融合矩阵,可实现对图像特征点、点云、融合特征点的实时更新;最后,分析本文算法的有效性以及特征点数量、观测高度、噪声大小对算法的影响。仿真结果表明,本文算法的精度和收敛速度均优于基于单一传感器的小天体运动状态估计方法。

应力状态对三点弯曲小试样蠕变性能评价的影响

针对大部分小试样技术没有规范化的标准,试样在尺寸上的变化往往会引起所受应力状态的变化,进而影响蠕变参数反演的准确性的问题,采用有限元法,基于三点弯小试样梁弯曲本构模型和Norton蠕变方程,分析试样在不同横截面宽厚比下的应力状态,及其对三点弯小试样蠕变性能的影响。研究结果表明,当横截面宽厚比b:2h<1:2时,试样趋向于平面应力状态;当b:2h>2:1时,试样趋向于平面应变状态;当1:2≤b:2h≤2:1时,试样介于两种应力状态之间。对于加载点稳态位移速率、蠕变应力、转换系数、蠕变参数反演结果,平面应力状态的影响明显大于平面应变状态;与单轴蠕变试验数据的对比结果表明,将试样横截面宽厚比控制在1:1≤b:2h≤2:1范围之内,能够提高蠕变参数反演结果的准确性。研究结果为三点弯小试样试验方法的合理应用提供依据。

Toward sustainable waste management in small islands developing states: integrated waste-to-energy solutions in Maldives context

Effective waste management is a major challenge for Small Island Developing States (SIDS) like Maldives due to limited land availability. Maldives exemplifies these issues as one of the most geographically dispersed countries, with a population unevenly distributed across numerous islands varying greatly in size and population density. This study provides an in-depth analysis of the unique waste management practices across different regions of Maldives in relation to its natural and socioeconomic context. Data shows Maldives has one of the highest population density and per capita waste generation among SIDS, despite its small land area and medium GDP per capita. Large disparities exist between the densely populated capital Male’ with only 5.8 km2 area generating 63% of waste and the ~194 scattered outer islands with ad hoc waste management practices. Given Male’s dense population and high calorific waste, incineration could generate up to ~30 GW/a energy and even increase Maldives’ renewable energy supply by 200%. In contrast, decentralized anaerobic digestion presents an optimal solution for outer islands to reduce waste volume while providing over 40%–100% energy supply for daily cooking in local families. This timely study delivers valuable insights into designing context-specific waste-to-energy systems and integrated waste policies tailored to Maldives’ distinct regions. The framework presented can also guide other SIDS facing similar challenges as Maldives in establishing sustainable, ecologically sound waste management strategies.

考虑直流侧动态的跟网型变换器稳定性分析

目前大部分关于并网变换器的研究忽略直流侧动态,在直流侧使用恒定电压源,一定程度上影响小干扰稳定性分析。文中主要考虑直流侧动态对跟网型变换器进行建模及稳定性分析。首先,分析新能源场站并网系统直流侧可等效为电压源和受控电流源的适用条件,论证并网变换器建模时考虑直流侧动态的必要性。随之,建立考虑直流侧动态的跟网型变换器谐波状态空间(harmonic state-space,HSS)阻抗模型。其次,在不同电网强度下,通过伯德判据对不同直流侧结构的系统进行稳定性分析,揭示电网强度对跟网型变换器稳定性的影响机理。然后,分析锁相环、电流环、滤波环节对系统阻抗特性的影响。最后,理论分析与电磁暂态仿真结果表明弱电网条件下,锁相环与电网呈现强交互作用,降低了系统的小干扰稳定性,且考虑直流侧动态的系统临界短路比更大。

大国对小岛屿国家气候援助的实践及影响:以“澳图条约”为视角

气候变化已经成为小岛屿国家最关切的议题之一,但多数小岛屿国家受限于其发展程度,只能依赖他国援助和支持以应对气候变化产生的影响。近年以来,这种需求正在变得愈发迫切。在2023年11月签订的“澳—图睦邻联盟条约(Australia-Tuvalu Falepili Union Treaty)”(以下简称“澳图条约”)中,图瓦卢以包括允许澳大利亚介入其外交和安全事务在内的高昂代价,换取澳大利亚的气候援助承诺。气候变化对小岛屿国家国际法人格和海洋权利的潜在影响,是理解双方合意缔结该条约真实动因的重要切入点。更为值得关注的是,“澳图条约”反映着部分大国以气候援助为支点,愈发深入地介入小岛屿国家内外事务的实践趋向。倘若类似“气候合作”由个例演变成固定的范式,大国将不断扩张在小岛屿国家的势力范围,其他小岛屿国家也将不得不为自身的生存而寻找大国的庇护,小岛屿国家为对抗大国控制而建立的区域组织也将被瓦解,进而彻底改变目前太平洋地区的地缘政治格局。大国与小岛屿国家应对气候变化的博弈,将对我国与小岛屿国家的深度合作产生潜在影响。有鉴于此,中国应从尊重国家主权和独立自主的基本立场出发,坚决抵制以气候合作为名干涉小岛屿国家内外事务的做法,并积极为小岛屿国家提供针对性的气候变化应对方案,推动前瞻性的“气候外交”布局。

基于VDCG的直流微电网退役锂电池SOC均衡方案

为增加系统惯性,直流微电网内锂电池控制器常采用虚拟直流发电机(virtual DC generator,VDCG)控制方案,但该方案无法使锂电池荷电状态(state of charge,SOC)自均衡。现有基于VDCG的锂电池SOC均衡方案仅能实现电压等级一致的非等容锂电池SOC均衡,而退役锂电池储能系统(retire lithium battery energy storage systems,RLBESS)的容量和电压等级均难以保持一致。针对此问题,提出了一种基于VDCG的适用于不同电压等级及容量的RLBESS组间SOC均衡方案。该方案在传统VDCG的基础上建立U-P_(m)关系式并引入SOC均衡因子,能够根据初始SOC状态自动调节锂电池的功率分配,并保持良好的电压质量。建立了所提方案的小信号模型,分析了关键控制参数对系统稳定性的影响。最后,利用Matlab/Simulink仿真软件对不同工况进行有效性验证。仿真结果表明:所提方案能够在锂电池电压等级不一致工况下实现RLBESS的SOC均衡,具有良好的可扩展性。

计及频率电压稳定性约束的电力系统多层级储能协同优化运行策略

高比例风电的接入使得电力系统调峰及消纳负担加重。为缓解上述压力,火电机组的开机规模通常会缩减,弱化了其在系统运行期间的频率电压支撑能力,致使系统静态电压及小扰动频率失稳风险增加。对此,该文考虑多元储能的协同互补作用,计及频率电压稳定性约束,提出一种多层级储能协同优化运行策略。首先,搭建风电场站级-电力系统级储能协同优化运行框架,据此提出场站级及系统级调度模型构建方法,并将线性化频率电压稳定性约束嵌入系统级调度模型;然后,采用主子问题分解迭代方法求解混合整数二阶锥系统级调度模型,避免直接求解导致的收敛缓慢或内存溢出问题;最后,开展算例分析,结果表明,所提策略能够有效地平抑风电出力波动、提高风电场调频支撑能力,同时可有效兼顾系统运行的经济性与频率电压的稳定性要求。

提高储能VSG并网有功响应性能的暂态阻尼策略

储能虚拟同步发电机(VSG)的并网有功在有功指令与电网频率2种扰动下存在动态超调与稳态偏差。提出有功微分反馈补偿(ADFBC)和有功微分前馈补偿(ADFFC)2种暂态阻尼策略,并在分别建立典型VSG、ADFBC和ADFFC 3种策略并网有功闭环小信号模型的基础上,给出了相应的参数设计方法。仿真和实验对比结果均验证了所提ADFBC和ADFFC暂态阻尼策略可有效提高储能VSG并网有功响应,在2种扰动下其并网有功既无动态超调又无稳态偏差。

基于有功微分补偿与虚拟惯量自适应的光储VSG控制策略

针对传统光储虚拟同步发电机(virtual synchronous generator, VSG)存在并网有功稳态偏差与系统动态振荡难以兼顾的问题,提出一种基于有功微分补偿(active power differential compensation, APDC)与虚拟惯量自适应的光储VSG控制策略。首先,建立了基于APDC算法的光储VSG并网有功闭环小信号模型,并通过极点分布图与伯德图的分析,讨论了APDC算法对系统暂态振荡与有功稳态偏差的抑制效果,给出了相关系数的整定方法。然后,为改善频率响应并避免有功超调量的增加,设计了一种基于APDC算法的改进型虚拟惯量自适应策略,同时给出其参数的取值范围。最后,实验结果表明,所提策略能消除VSG并网有功的动态振荡与稳态偏差,具有更小的频率偏差与频率变化率。

国有企业“小微权力”监督的多元逻辑与整合路径——以国网常州供电公司为例

加强国有企业“小微权力”监督是推进中国式现代化的必然要求,但现有廉政研究的断裂性难以支撑权力监督向国企基层的延伸。从委托-代理关系切入,构建国有企业“小微权力”监督体系的整合性分析框架,以国网常州供电公司为例,分析“小微权力”监督的结构逻辑、内在矛盾,并尝试提出优化思路。研究发现,国企“小微权力”监督体系的设立遵循政治逻辑、效率逻辑和服务逻辑,但不同监督方式的逻辑冲突造成了目标置换、行为避责和参与有限的困境。针对这些问题,应该在整体治理系统的视角下建立立体化“小微权力”监督体系,以政治逻辑为引领,以效率逻辑为基础,以服务逻辑为根本,通过数字技术赋能监督。

不同风光水配比下多类型电源打捆直流外送系统的功率传输能力研究

风光水打捆经电网换相换流器高压直流输电(line commutated converter based high voltage direct current,LCC-HVDC)外送系统中,风光水配比不同会影响系统的功率传输能力。文章首先建立风光水打捆直流外送系统的稳态数学模型和状态空间模型,然后提出综合考虑稳态运行约束条件和小信号稳定性约束条件的系统功率传输能力计算方法及流程,掌握不同功率水平下系统稳定运行区域及边界的变化特征,最终得到不同水电出力下的直流外送系统功率传输范围、特定传输功率下所允许的水电出力最小值、风光配比与小信号稳定性的定量关系。通过该方法定量评估风光水配比不同时直流外送系统的功率传输能力,从而优化选取风光水配比。结果表明,水电出力较小时,系统传输功率上限受小信号稳定性制约,下限受电压偏移约束制约;水电出力较大时,系统传输功率上限受LCC-HVDC安全运行约束制约,下限受逆变侧电压偏移、系统潮流约束制约;在功率运行点不变时,风光配比平衡工况系统更加稳定。最后,通过PSCAD/EMTDC下的电磁暂态仿真,验证上述功率传输能力理论计算的正确性。