3D Track-keeping Method for Autonomous Underwater Vehicle

In this paper, 3D track-keeping control method for autonomous underwater vehicle (AUV) with and without the influence of ocean current is investigated. Because the system to be controlled is highly nonlinear and strong coupled, an approach is used to divide it into two subsystems. One is to control the heading and the track error on the horizontal plane. The other is to control the pitch and the track error on the vertical plane. The results of computer simulation show that the autopilot works properly, it can capture the current waypoint and turns to track the next path automatically.

Future Changes in Extreme High Temperature over China at 1.5℃-5℃ Global Warming Based on CMIP6 Simulations

Extreme high temperature(EHT)events are among the most impact-related consequences related to climate change,especially for China,a nation with a large population that is vulnerable to the climate warming.Based on the latest Coupled Model Intercomparison Project Phase 6(CMIP6),this study assesses future EHT changes across China at five specific global warming thresholds(1.5℃-5℃).The results indicate that global mean temperature will increase by 1.5℃/2℃ before 2030/2050 relative to pre-industrial levels(1861-1900)under three future scenarios(SSP1-2.6,SSP2-4.5,and SSP5-8.5),and warming will occur faster under SSP5-8.5 compared to SSP1-2.6 and SSP2-4.5.Under SSP5-8.5,global warming will eventually exceed 5℃ by 2100,while under SSP1-2.6,it will stabilize around 2℃ after 2050.In China,most of the areas where warming exceeds global average levels will be located in Tibet and northern China(Northwest China,North China and Northeast China),covering 50%-70%of the country.Furthermore,about 0.19-0.44 billion people(accounting for 16%-41%of the national population)will experience warming above the global average.Compared to present-day(1995-2014),the warmest day(TXx)will increase most notably in northern China,while the number of warm days(TX90p)and warm spell duration indicator(WSDI)will increase most profoundly in southern China.For example,relative to the present-day,TXx will increase by 1℃-5℃ in northern China,and TX90p(WSDI)will increase by 25-150(10-80)days in southern China at 1.5℃-5℃ global warming.Compared to 2℃-5℃,limiting global warming to 1.5℃ will help avoid about 36%-87%of the EHT increases in China.

Does the Global Warming Pause in the Last Decade:1999-2008?

Issues related to the pause of global warming in the last decade are reviewed.It is indicated that:(1) The decade of 1999-2008 is still the warmest of the last 30 years,though the global temperature increment is near zero;(2) Natural factors such as volcanism,solar radiation,ENSO,and thermohaline circulation can have impact on the inter-annual and inter-decadal variability of global mean temperatures.However,it will not mask the global warming trend for a long time;(3) Temperatures of China continue to increase in 1999-2008 with an increment of 0.4-0.5℃per 10 years.

10-25-Day Intraseasonal Variations of Convection and Circulation Associated with Thermal State of the Western Pacific Warm Pool during Boreal Summer

This study focuses on the characteristics of 10-25-day oscillation associated with the interannual variability of the thermal state in the western Pacific warm pool. The time series of 10-25-day oscillation shows a distinct feature between warm (WARM case) and cold (COLD case) summers over the western Pacific warm pool. The significant negative relationship between the time series of 10-25-day convection anomalies in Warm and Cold cases appears over most of Asian-Pacific region manifesting the interactions between the convection on interannual and 10-25-day intraseasonal time scales. At the peak and trough stages of 10-25-day convection oscillation, a Gill-type low-level atmospheric circulation anomaly, cyclonic or anticyclonic. appears northwest of the convection anomaly. This relationship between the convection and circulation exists both in Warm case and in Cold case. However, at other stages rather than the peak and trough stages, there is no Gill-type circulation response, and the circulation anomaly shows a distinct feature between the Warm and Cold cases, although the convection oscillation exhibits a roughly similar feature.

Public Building Supervisors＇ Assessment of Site Progress Record Keeping Practices in Abuja, Nigeria

The importance of good site progress records in quality assurance; tracking project progress; preparing, analyzing and resolving claims; and placing responsibilities in the event of dispute in building contracts is widely recognized. This study engaged Public Building Supervisors in the assessment of site progress record keeping practices in Abuja. A simple structured questionnaire （which mainly assessed the nature and importance of records kept, reasons for keeping them; level of satisfaction with the current approach, challenges and practical ways of improving the practice） was administrated to a hundred of the supervisors, out of which seventy one was properly completed and returned. The results show that all five site progress documents （minutes of progress meetings, day-work sheets, photographs, weekly site records and personal site diaries） found in literature, are in use in Abuja, and have at least a high importance rating （i.e., relative importance index, 0.6 〈 RII 〈 0.8）. Prominent among the reasons for keeping the records are： control of ongoing work （R11 = 0.83） data for estimating future works and terms of contract requirement （each with RII = 0.823）. Though the present record keeping practices were largely assessed satisfactory, 95% of the Supervisors still yearned for improvement. The challenges to the current practice are consistent with those identified in literature and are： continuity consistency, legibility and accountability; in descending order of frequency of occurrence. Computerization, regular inspection of progress documents by assigned supervisors and in-house training of site staff are recommended for improving the record keeping practices.

连铸机-棒材工艺装备的优化

以某钢企炼钢连铸机-轧钢棒材为一体化直接轧制实例,在原有工艺基础上进行了装备及直轧工艺技术改进,将连铸机半径优化为8 m,结晶器长度优化为0.9 m。分析了连铸机新装备工艺参数、钢液浇铸准备时间、作业时间、年度产量、高拉速与二次冷却对钢液凝固的影响。通过采用高拉速结晶器、非正弦电动振动、液压剪剪切、免加热钢坯和轧机前保温辊道罩内等待位排序、钢坯全程保温快速输送等关键工艺技术,实现了钢坯从炼钢连铸机到轧钢棒材第一架轧机108 m全程保温输送。合理利用加热炉出钢炉门及炉内悬臂辊道路径直线输送钢坯到轧机轧制的一种全新直接轧制模式,使技术指标达到国内先进。采用全新直接轧制技术节省了大量煤气,减少了SO2、NOx、粉尘等污染物的排放,做到了绿色、低碳轧制,产生了良好的社会和经济效益,为国内同行起到了示范作用。

采用Sillwarm超细旦腈纶开发轻量保暖面料

Sillwarm超细旦腈纶是湿法纺丝技术代表产品之一,具有细、柔、轻、弹的仿绒特性。简述采用Sillwarm超细旦腈纶开发一种冬季轻量保暖舒适型运动面料的编织工艺、染整工艺流程,并与运动服装常用的棉、涤棉混纺材质性能相比较,测试分析产品的主要性能。结果表明,本次开发面料的可织性、染色性较好,产品吸湿好、蒸发性强,并且具有较好的抗起毛起球性能,适用于秋冬季轻量保暖型产品的开发。

Nonlinear High Harmonics Generation in REB-Plasma System

The interaction of a relativistic electron beam (REB) with inhomogeneous, magneto-active, relativistic warm plasma is theoretically investigated. The nonlinear formation of waves at second and triple frequency at the inlet of the beam into the plasma is investigated. Effects of external static or oscillating magnetic field are considered. Nonlinear effects associated with the generation of second and triple harmonics, play an important role in the process of energy transfer from the beam to the plasma as compared with linear stage.

阻燃保暖起绒面料开发

传统阻燃面料因为面料编织工艺的问题,存在手感不佳、普遍偏硬、抓绒效果差现象,从而导致保暖性不好、服用性能差等缺点。现阶段各品牌及消费者对于舒适性要求愈发提高,因此市场亟需开发一种具备高舒适性、良好阻燃与保暖性的针织面料。文中重新设计了阻燃针织基本针织织造工艺,并从织造线圈长度、沉降片高度、面料包覆性等方面对针织织造工艺进行了研究和优化,同时对清洁装置进行了改进,开发了符合项目要求的阻燃保暖起绒面料。

Keeping Warm Without Coal

Heat-pump technology offers a clean heating alternative to coal With no air conditioning or indoor heating, families in southeast Beijing’s Fangzhuang neighbor-hood still enjoy refreshing warm air all year round. The secret is in the pump technology. Heat pumps cool the homes in summer and warm them in winter just like a central air-conditioning system.

保温措施对结肠癌根治术患者术中体温的影响

目的观察综合体温管理措施对结肠癌根治术患者围手术期体温变化的影响。方法将40例结肠癌患者随机分为保温组和对照组各20例。保温组用温热敷纱擦拭止血并覆盖肠管、温热盐水湿润冲洗腹腔,加温输注液体及血液;对照组采用常规术中护理,手术中持续监测病人的直肠温度变化,记录患者入室时、切皮时、术中、术毕体温。结果保温组患者肛温在切皮时及其后各时间点与入室时相比,差异不明显(P>0.05)。而对照组患者的肛温术中和术后逐渐下降,与入室时相比差异有统计学意义(P<0.05)。两组间比较显示:入室及切皮时两组间肛温无差异(P>0.05);与对照组相比,保温组术中及术毕肛温较高,差异有统计学意义(P<0.05)。结论在结肠癌根治手术中,综合保温措施可有效地维持患者的体温恒定,预防术中低温的发生。

铁路路基冻害防治保温技术研究

通过理论分析和现场试验等方法开展了路基冻害防治保温技术的研究。分析了保温材料应用于季节性冻土重载路基的适用性,模拟了不同保温板厚度条件下路堤和路堑温度场的分布特征,提出了消除冻害所需的保温材料及其厚度,形成了保温板的施工工艺流程。现场试验结果表明,试验地段的冻害得到了有效治理。

蝴蝶兰智能温室催花技术研究

利用现代智能温室设施，探讨不同温度、光照、肥料对蝴蝶兰花芽分化的影响，结果表明，在日温22～24℃，夜温16～17℃，每天低温处理16h．光照25000～30000lx的条件下．配合施用N：P：K配比为9：45：15的肥料，蝴蝶兰花芽分化率最高，生长效果最好。

中空异形涤纶面料性能研究

中空异形涤纶纤维具有吸湿排汗和保暖性能,它采用了全新的纤维截面设计,将毛细管原理应用于纤维和纱线结构,使织物能够快速导湿、扩散和挥发汗液,从而保持人体皮肤的干爽感,达到提高织物舒适性目的。对中空异形涤纶、Coolmax、Coolbst、普通涤纶纤维等机织物的热湿性能进行了测试分析,认为该纤维保暖性能突出,但透气性及透湿汽性较差。

卫生坑道工作环境调查

[目的]了解卫生坑道环境卫生状况,为特殊情况下人员进驻后做好防潮保暖工作提供科学依据。[方法]气温和气湿检测采用HT-2126型数字显示温湿度计,风速采用EYⅡB型便携式数字风速表,O2和CO2采用CYES-11型气体测定仪,CO、NO、NO2和SO2采用2000系列有害气体监测报警仪。空气细菌总数和真菌数用沉降法检测。[结果]卫生坑道内平均气温9.45℃:,平均气湿33.9%,风速为0m/s。气体成分检测结果均属正常。细菌总数为(3700±1016.3)cfu/m3,真菌数(4400±1060.6)cfu/m3,链球菌数(97±76.3)cfu/m3,厌氧菌(550±314.3)cfu/m3。实验组与对照组比较,细菌总数、真菌数差异有非常显著性(P<0.01),链球菌数差异有显著性(P<0.05)。[结论]卫生坑道收治的主要是伤病员,机体免疫力普遍较低,在其特殊环境下应做好防潮保暖及健全严格的消毒制度,以预防和控制因环境因素对人体健康的影响。

保温护理对老年低体温患者术后复苏期的影响

目的探讨麻醉复苏期采用不同保温措施对低体温老年患者手术后的影响。方法将150例全身麻醉的低体温老年手术患者随机分为观察组和对照组。对照组采用常规调节室温加盖棉被的方法保温;观察组除以上护理措施外增加充气式保温毯包裹患者躯干部及双下肢进行保温。比较分析两组低体温老年患者复苏期生命体征、复苏时间、体温及并发症发生情况。结果观察组氧饱和度明显高于对照组,差异有统计学意义(P<0.05),而两组患者其他生命体征如心率、收缩压、舒张压比较差异均无统计学意义(P>0.05);观察组苏醒时体温显著高于对照组,而苏醒时间显著低于对照组(P<0.05);观察组寒颤、躁动等并发症发生率显著低于对照组(P<0.05)。结论保温护理可以明显提高全身麻醉低体温老年患者的氧饱和度、体温、苏醒时间,并能显著降低并发症的发生。

早产儿体温管理研究进展

文章综述了国内外早产儿出生、转运过程、进入新生儿重症监护病房后及日常保暖措施,并对如何提高早产儿入室体温、降低并发症、提高生存质量进行了展望,旨在为临床护理工作者提供理论依据。

兔舍自动投食喂水采光装置的设计

为了实现对兔养殖的自动化管理,设计了兔舍自动投食、喂水、采光装置。该装置由机械系统和单片机控制系统共同组成。机械系统主要功能有投食、喂水和太阳光跟踪等;单片机控制系统能够准确按照设定时间和设定的投食喂水量进行工作,并控制兔舍的光照、温度、通风等,实现了兔舍的自动管理,极大节省人力。系统结构简单,使用方便,运行稳定,适合于在农村应用。

利用“三废”制轻型保温隔热建筑材料

塑料的问世给人们的日常生活带来了极大方便的同时 ,也给人类居住环境造成很大破坏。人们使用后的聚苯乙烯泡沫包装盒 (板 )和塑料袋随处可见 ,形成了难以消除的“白色污染”。还有工业废渣到处堆积如山 ,没有得到充分利用。针对这种情况 ,笔者为了开发这些“三废”材料的新用途 ,利用泡沫塑料和炉渣表观密度小、空隙率大、保温隔热性能好等特性 ,研制了一种轻型保温隔热建筑材料 ,经过实验取得了良好效果。

数字化水暖床在妇科肿瘤根治术中的应用研究

目的探讨数字化水暖床在妇科肿瘤根治术中的应用效果。方法选取我院2015年1月~2017年12月收治的120例妇科肿瘤根治术患者作为研究对象。按照随机方法分为对照组(60例)与研究组(60例)。对照组室温维持在22~25℃,术中冲洗液加温至37~38℃,常规覆盖保暖毛毯或棉被,床垫铺上预热保暖毯;研究组在对照组基础上,将预热保暖毯改用数字化水暖床保暖。比较两组的术中低体温发生率和麻醉恢复期寒战发生率、术后气管导管拔管时间和术后清醒时间。结果研究组患者的术中低体温发生率、麻醉恢复期寒战发生率低于对照组,术后气管导管拔管时间和清醒时间短于对照组,差异有统计学意义(P<0.001)。结论数字化水暖床应用于妇科肿瘤根治术患者可效有降低术中低体温发生率和麻醉恢复期寒战发生率,缩短患者的气管导管拔管时间和术后清醒时间,促进其术后康复。