Progress on Integrated Control of Tobacco Black Shank

Tobacco black shank is one of the devastating diseases of tobacco. In recent years, this disease widely occurred in most tobacco-growing areas, which caused disastrous losses and has severely threatened the sustainable development of flue-cured tobacco. In order to lay a theoretical foundation for the better control of tobacco black shank, the occurrence characteristics and integrated control strategis of this disease were systematically discussed according to the aspects of agricultural control, chemical control, biological control, etc.

Introduction to the theory and technology on downhole control engineering and its research progress

On the basis of reviewing the development history of drilling engineering technology over a century, this paper describes the technical and scientific background of downhole control engineering, discusses its basic issues, discipline frame and main study contents, introduces the research progress of downhole control engineering in China over the past 30 years, and envisions the development direction of downhole control engineering in the future. The author proposed the study subject of well trajectory control theory and technology in 1988, and further proposed the concept of downhole control engineering in 1993. Downhole control engineering is a discipline branch, which applies the perspectives and methods of engineering control theory to solve downhole engineering control issues in oil and gas wells; meanwhile, it is an application technology field with interdisciplinarity. Downhole control engineering consists of four main aspects; primarily, investigations about dynamics of downhole system and analysis methods of control signals; secondly, designs of downhole control mechanisms and systems, research of downhole parameters collections and transmission techniques; thirdly, development of downhole control engineering products; fourthly, development of experimental methods and the laboratories. Over the past 30 years, the author and his research group have achieved a number of progress and accomplishments in the four aspects mentioned above. As a research field and a disciplinary branch of oil and gas engineering, downhole control engineering is stepping into a broader and deeper horizon.

The usefulness and significance of assessing rapidly progressive spermatozoa

It is possible and clinically relevant to distinguish between slow and rapid progressive spermatozoa in basic semen analysis. This is discussed in light of the different purposes of semen analysis for the subfertile couple and the male patient. The two groups of progressive spermatozoa should be distinguished to help ensure that pertinent information available in the semen sample is not neglected.

冲击地压主控因素及孕灾机制

随着我国煤矿逐步向深部开采转移,冲击地压灾害日趋严重。在冲击地压从机理认知走向防冲工程进程中,首要的任务是厘清冲击地压孕灾主控因素,并进行风险程度判识。在上百个冲击地压矿井致灾评价分析基础上,提出了导致冲击地压发生的4类客观主控因素:煤岩冲击倾向性、开采深度、坚硬顶板、地质构造,以及3类人为主控因素:煤柱、采空区及采掘卸荷,并对各主控因素对冲击地压孕灾的力学机制进行了分析讨论。在客观主控因素方面,煤岩冲击倾向性是煤岩积聚变形能进而诱发冲击破坏的自身属性;开采深度与巷道围岩内积聚的变形能呈正相关关系,是冲击地压发生的必要条件;坚硬顶板大尺度周期断裂形成的冲击动载及动能是诱发冲击地压的“导火索”;地质构造对冲击地压的影响显著,对于断层构造而言,断层两盘将在开采扰动造成的突发卸荷影响下产生相对“回弹”;煤层变薄区等效弹性模量变大,超前支承压力呈“双峰值”分布,使得冲击影响范围扩大。在人为主控因素方面,煤柱作为高应力集中区,其尺寸、倾角及相对位置等将直接影响冲击地压发生的概率和强度;采空区会诱发超前支承压力集中区内围岩积聚弹性能的突然释放,尤其是在采高较大、顶板垮落不充分的情况下;采掘卸荷会导致应力集中区快速“迁移”,引发煤体内弹性应变能的大量释放,是造成冲击地压的重要外因条件。在此基础上,对山东新汶、山东鲁西、内蒙古鄂尔多斯、陕西彬长、新疆和甘肃等矿区冲击地压孕灾主控因素差异性,进行了对比分析,强调按层次对矿井、采区和工作面进行冲击地压主控因素及其影响程度判识重要性,构建了从降能、释能、阻能到抗能的冲击地压治理工程路径。

Application of PI Control Algorithm to Discrete Manufacturing Systems

PI （proportional-integral） control algorithm is applied to control WlP （work-in-progress） in a discrete manufacturing system, where the cascade control of PI controllers is presented. It is in the frequency domain that the PI controller is designed with constraints on sensitivity options to ensure the stability and robustness of its parameters. A case is evaluated on a motorcycle engine crankcase production system, whose simulation results confirm that demand fluctuations can be compensated by PI controllers under a normal demand. PI controllers also possess low sensitivity to the distribution of production times.

An ARX-Based PID-Sliding Mode Control on Velocity Tracking Control of a Stick-Slip Pi-ezoelectric-Driven Actuator

Piezoelectric-driven stick slip actuators have been drawn more and more attention in the nano- positioning application due to the high accuracy and theoretical unlimited displacement. However, the hysteresis of piezoelectric actuator (PEA) and the nonlinear friction force between the end- effector and the stage make control of piezoelectric-driven stick slip actuator challenge. This paper presents the development of an autoregressive exogenous (ARX)-based proportional-integral-derive (PID)-sliding mode control (SMC) for the velocity tracking control of the piezoelectric-driven stick slip actuator. Stability is guaranteed by rigorously choosing the appropriate PID parameters and the zero steady state error is achieved. To verify the effectiveness of the proposed method, experiments were carried out on a commercially-available piezoelectric-driven stick slip actuator. The tracking errors were compared with the traditional PID controller, illustrating that in spite of existing of modeling error, the ARX-based PID-SMC is able to better improve the velocity tracking performance of piezoelectric-driven stick slip actuator, compared with the traditional PID controller.

Corneal Wavefront Aberrations in Patients Wearing Multifocal Soft Contact Lenses for Myopia Control

Purpose: The purpose of this study was to evaluate the change in corneal wavefront aberrations in young adults who have been fit with multifocal soft contact lenses for myopia progression control. Findings have been analyzed for statistical significance and clinical relevance and compared to reportedly successful Orthokeratology outcomes. Methods: The dominant eye of 40 participants (27 women, 13 men;mean age 27.3 ± 3.2 years;range 23 to 39 years) was fit with Proclear Multifocal center distance lenses (Coopervision, Pleasanton, USA) having a variety of distance powers and reading additions. Refractive errors were limited to a range of –6.00 D up to +1.00 D of sphere, and no greater than –1.00 D of cylinder. Corneal wavefront measurements were performed over 6 mm diameters with a Zeiss Atlas 9000 corneal topographer (Zeiss Meditec, Dublin, USA) prior to, and following lens fitting. Data were converted into rectangular Fourier optics terms M, J0, J45 and RMS values for each reading addition were statistically analyzed. Following evaluation of statistical significance and clinical relevance, results were compared to published data from successful Orthokeratology treatments. Results: Statistically significant changes in higher order aberrations were detected for lenses of all reading additions. Lens groups with higher Add-powers demonstrated stronger changes with increased significance. Final RMS values relating to 2nd, 3rd and 4th Zernike Orders reached clinical significance with a wavefront error of 0.10 μm, the equivalent of 0.25D. Moreover, as Add-powers increased, 3rd and 4th order aberrations likewise showed an increase. Pre-fitting astigmatism values accounted for the highest recorded aberrations and remained predominantly unchanged. Conclusion: Proclear Multifocal center-distance contact lenses were found to increase higher order wavefront aberrations in a manner dependent on their Add-power. In comparison to successful Orthokeratology outcomes, the amounts of resulting aberrations are notably different.

地外天体软着陆自主导航与控制技术研究进展

软着陆探测是重要的地外天体探测方式,制导、导航与控制(Guidance,Navigation and Control,GNC)是地外天体软着陆成功的关键。首先梳理了国内外月球、火星和小天体等地外天体软着陆任务发展现状;在此基础上,总结了地外天体软着陆任务典型GNC方案及自主导航与控制技术主要进展;最后,针对未来的地外天体精确定点软着陆任务,提出了需要重点关注和发展的自主导航与控制关键技术,为未来技术发展提供借鉴和参考。

2023年茶树病虫害防控研究进展

文章系统综述了2023年茶树病虫害防控研究进展。国内外取得的主要研究进展包括,挖掘出一批茶树主要病虫害的高效微生物防控资源和天敌昆虫,解析了我国茶园重大害虫茶小绿叶蝉的求偶振动通信,鉴定出高效调控茶树-灰茶尺蠖、茶树-茶小绿叶蝉-寄生蜂间互作关系的化学信息,建立了茶树病虫害快速识别的多种模型。这些结果将为今后茶树病虫害高效绿色防控技术的创新研发提供有力支撑。

香菇工厂化生产研究进展

香菇是我国食用菌中年产量最大的单品。随着产业的发展,集约化、工厂化生产逐渐成为一种趋势。“集中制棒,分散出菇”成为我国香菇栽培的主流模式。相关研究和生产应用取得了较大进步,该文从品种选育、生产过程调控等方面对此进行了综述,以期为香菇工厂化生产提供参考依据。

桑椹菌核病的发生与防治技术研究进展

文章介绍了桑椹菌核病的病原菌和发病症状,从发生条件、侵染过程及流行规律等方面阐述了桑椹菌核病的发生规律,从品种抗病性、菌源积累、气候条件和栽培管理等方面分析了桑椹菌核病的发生原因,从选用抗病品种、加强田间管理和清除菌源等方面介绍了桑椹菌核病的农业防治措施,从生防菌筛选和绿色防控药剂的筛选等方面介绍了主要生物防治技术,介绍了不同化学农药对桑椹菌核病的防治效果及其农药残留情况。笔者认为对桑椹菌核病的防治,应在选用抗病品种、科学栽培、及时清除菌源等农业防治措施的基础上,采取生物防治为主、药剂防治为辅的综合防治模式,既能较好地控制病害的发展,又能满足人们对绿色食品的需求。

扩大翼点入路逐步控制性减压手术治疗重型颅脑损伤的效果分析

目的:分析扩大翼点入路逐步控制性减压手术治疗重型颅脑损伤的效果。方法:选取2021年1月—2023年1月钦州市第二人民医院神经外科收治的重型颅脑损伤患者86例作为研究对象,随机分为对照组和观察组,各43例。对照组采用大骨瓣减压术联合传统快速减压术治疗,观察组采用扩大翼点入路逐步控制性减压术治疗。比较两组颅内压、美国国立卫生研究院脑卒中量表(NIHSS)评分、格拉斯哥昏迷指数(GCS)评分及预后情况。结果:开颅前,两组颅内压水平比较,差异无统计学意义(P>0.05);术后24、72 h,两组颅内压水平降低,观察组低于对照组,差异有统计学意义(P<0.05)。术前,两组NIHSS、GCS评分比较,差异无统计学意义(P>0.05);术后72 h,两组NIHSS评分降低,观察组低于对照组,两组GCS评分升高,观察组高于对照组,差异有统计学意义(P<0.05)。观察组预后良好率高于对照组,差异有统计学意义(P=0.030)。结论:扩大翼点入路逐步控制性减压手术治疗重型颅脑损伤的效果显著,可降低颅内压水平,改善患者神经功能、昏迷程度及预后。

酿造调味品中生物胺分析与控制研究进展

酿造调味品在发酵过程中易产生多种潜在的有毒代谢物,其中生物胺是影响其质量和安全的重要风险因素之一,过量摄入会使人体产生各种毒害反应,从而对健康造成不良影响。文章对生物胺的产生原因、毒性和检测方法进行了归纳,并重点阐述了国内外关于生物胺的物理、生物和化学的防控措施,以期为酿造调味品的食用安全性及有效控制提供新思路。

政府集中建设模式下高校学生宿舍楼建设进度控制探讨

近几年,随着教育事业的快速发展,高校学生宿舍楼建设被视为重要民生工程,其进度控制研究更加深入,涉及资源配置、风险评估及多方协作等多个方面。高校宿舍楼建设项目在省本级政府投资项目集中建设模式下,规模庞大、周期紧迫,其建设进度直接关系到学生的居住安全与满意度,乃至学校的教学秩序与整体发展。然而,实际建设中常面临资金筹措、设计变更、施工协调等多重挑战,导致进度延误现象频发影响新生入住。本研究旨在通过分析现状问题,提出针对性建议,为高校宿舍楼建设管理提供理论与实践参考。

蒙药材质量标准及质量控制方法的研究进展

蒙药材质量稳定是保证蒙医药长久发展的首要前提。建立科学、完善的药材质量标准不仅可以保证临床用药的安全、有效,可为后续蒙药制剂的生产提供稳定的质量保证。本文对历版蒙药材及饮片质量标准的主要内容进行对比总结,阐述蒙药材标准的变化历程;总结蒙药材质量标准及现代分析技术中常见的质量控制方法;并对质量标准中存在的问题进行分析讨论,为推动蒙药标准化、现代化发展提供参考。

荔枝和龙眼尺蛾科害虫的研究进展

鳞翅目(Lepidoptera)尺蛾科(Geometridae)成虫多为中型蛾类,其幼虫称为“尺蠖”,是荔枝和龙眼梢期的重点防控对象之一。目前,我国已报道的危害荔枝和龙眼的尺蛾科害虫共有10种,广东省内常见的有8种,分别为:粗胫翠尺蛾Thalassodes immissaria、大造桥虫Ascotis selenaria、大钩翅尺蛾Hyposidra talaca、油桐尺蛾Biston(Buzura)suppressaria、波纹黄尺蛾Perixera illepidaria、樟翠尺蛾Thalassodes quadraria、荔枝青尺蛾Berta chrysolineata hainanensis和间三叶尺蛾Sauris interruptaria。至今,国内外围绕荔枝和龙眼尺蛾科害虫开展的研究报道仅为15篇,其中粗胫翠尺蛾最多(7篇),而为害较普遍的荔枝青尺蛾和间三叶尺蛾尚未见研究报道。本文基于文献检索结果,着重综述了粗胫翠尺蛾、大造桥虫、大钩翅尺蛾、绿额翠尺蛾Pelagodes proquadraria和油桐尺蛾5个尺蛾科优势种的研究现状,并且从农业防治、物理防治、生物防治和化学防治4个方面概述了国内外荔枝和龙眼尺蛾科害虫综合治理技术研究进展。目前,尺蛾科害虫的生物防治技术研究集中于天敌的保护利用、生物源农药和昆虫性信息素的开发与应用。至今,已有粗胫翠尺蛾、大造桥虫、槐尺蛾Chiasmia cinerearia和油桐尺蛾4种尺蛾的性信息素有效组分被成功鉴定。但当前针对尺蛾科害虫仍以化学防治为主,而且我国用于荔枝和龙眼尺蛾科害虫防治的杀虫剂尚无登记,对农技推广人员指导用药提出了巨大挑战。本综述旨在帮助广大科研工作者全面了解此类害虫的研究现状,以期为尺蛾科害虫的深入研究及综合防控新技术的研发提供参考。

中医药调控线粒体质量控制治疗缺血性卒中的研究进展

缺血性卒中是一种常见的脑血管意外,日益成为严重的全球性健康问题。线粒体质量控制失调是脑缺血诱导神经元死亡的重要机制,维持线粒体功能对于促进神经元存活和改善神经功能至关重要。线粒体质量控制主要涉及线粒体氧化应激、线粒体动力学、线粒体自噬、线粒体生物发生等方面,是稳定线粒体正常结构、发挥线粒体正常功能的重要条件。近年来,中医药通过多角度、多通路、多靶点调控线粒体质量控制,通过影响线粒体结构与功能,能显著改善缺血性卒中患者临床症状,受到了学者们的广泛关注。本文通过对近年来应用中药有效化合物成分及中药复方调控线粒体质量控制治疗缺血性卒中的实验研究和临床观察进行归纳总结,进一步阐释缺血性卒中的发病机制,明确中医药对线粒体质量控制的调控机制,总结中医药治疗缺血性卒中的科学内涵与不足之处,以期为临床进一步应用中医药参与治疗缺血性卒中提供一定的思路与方法。

A Standard Framework for Effective Progress Reports in the State of Kuwait

The construction industry in the State of Kuwait has recently witnessed a rapid growth as the volume of construction projects increased significantly over the past decade. Because of the progress and growth of the industry and the size of the projects, the volume of disputes between the parties to the various contracts has increased accordingly. As projects become larger and more complex, their management and control become more difficult, especially in the absence of effective standard systems to for managing project progress and determining the delay, if any. Even the simple issues, as well as the large ones, if neglected and unaddressed in a timely manner, can cause huge problems that concerns to all project parties. Irrespective of addressing and managing construction delays legally, the resulting legal disputes always have other negative effects on the contracting parties. If the parties to the contract have an insight that enables them to forecast and identify the issues that may cause a conflict before it occurs, that eliminates a myriad of problems before they occur, and greatly reduces the chances of further conflict between contracting parties. This paper presents a framework for a novel progress reporting system that can help minimize contract disputes in the state of Kuwait.

芒果采后主要真菌性病害及防治方法研究进展

芒果是热带、亚热带重要经济作物之一,因其独特的口感和丰富的营养价值深受消费者喜爱。由于芒果采收期正值高温多雨季节、果实采后生理代谢旺盛、采收难度大,采后运输、贮藏过程中易遭受真菌的侵染,成为限制芒果产业发展的重要因素。为防治芒果采后真菌性病害,国内外学者对芒果采后防治技术进行了研究与开发。对炭疽病、蒂腐病和曲霉病3种芒果采后主要真菌性病害的症状、危害、病原菌和发生条件进行了综述,总结了芒果采后真菌性病害的防治方法,并对芒果采后病害防治方法进行了展望,为芒果采后真菌性病害防治技术的发展提供理论基础。