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71.
我国海域使用动态监测系统(SDMS)模式探讨   总被引:1,自引:0,他引:1  
海域同土地一样是我国重要的基础资源,同时具有国民经济、生态环境、国防安全等方面的重要意义。由于我国历史上对海域使用缺乏有效的监测,海域管理者无法准确掌握海域使用的现状与动态,海域管理的科学决策存在很大难度,从而引发了一系列海洋资源、生态环境方面的问题。论文基于海域使用自身的特点分析,同时参考了相关的监测模式,从技术体系和业务体系两个方面对我国海域使用动态监测系统(Sea area usage Dynamic Monitoring System, 简称SDMS)的构建模式进行了探讨,初步建立了SDMS的概念模型。  相似文献   
72.
智能安全帽侧压性能试验机采用电脑程序控制、伺服控制等技术,使安全帽侧压性能测试实现自动化操作,完全克服了人为因素对测试数据的影响,且读数直观,无需计算,操作便捷,在国内外同类设备中尚居首类。  相似文献   
73.
促进循环经济发展的税收政策   总被引:3,自引:0,他引:3  
循环经济是一种全新的经济模式,它关注的是资源减量、循环及再利用的问题。介绍了国外发展循环经济所采取的税收政策,指出我国目前在该领域所存在的问题,并根据我国的实际情况,提出了促进发展循环经济的税收政策,包括:完善现有税种,开征环境保护税,建立“绿色关税”体系,尽早开征燃油税,制定激励机制,开征社会保障税。  相似文献   
74.
为有效预防由于个人防护缺失所造成的事故,着力探究复杂作业情况下施工人员安全帽佩戴情况的智能化识别.提出在Faster R-CNN目标检测算法的基础上,针对小目标的安全帽识别问题通过增加锚点提升检测能力,为解决数据集中类别不平衡问题采用Focal loss替代原本的损失函数,为解决安全帽预测区域不匹配问题,引入ROI A...  相似文献   
75.
Objective: Rapid urbanization and motorization without corresponding increases in helmet usage have made traumatic brain injury due to road traffic accidents a major public health crisis in Cambodia. This analysis was conducted to quantify the impact of helmets on severity of injury, neurosurgical indication, and functional outcomes at discharge for motorcycle operators who required hospitalization for a traumatic brain injury following a road traffic accident in Cambodia.

Methods: The medical records of 491 motorcycle operators who presented to a major tertiary care center in Cambodia with traumatic brain injury were retrospectively analyzed using multivariate logistic regression.

Results: The most common injuries at presentation were contusions (47.0%), epidural hematomas (30.1%), subdural hematomas (27.9%), subarachnoid hemorrhages (12.4%), skull fractures (21.4%), and facial fractures (18.5%). Moderate-to-severe loss of consciousness was present in 36.3% of patients. Not wearing a helmet was associated with an odds ratio of 2.20 (95% confidence interval [CI], 1.15–4.22) for presenting with moderate to severe loss of consciousness compared to helmeted patients. Craniotomy or craniectomy was indicated for evacuation of hematoma in 20.0% of cases, and nonhelmeted patients had 3.21-fold higher odds of requiring neurosurgical intervention (95% CI, 1.25–8.27). Furthermore, lack of helmet usage was associated with 2.72-fold higher odds of discharge with functional deficits (95% CI, 1.14–6.49). In total, 30.1% of patients were discharged with severe functional deficits.

Conclusions: Helmets demonstrate a protective effect and may be an effective public health intervention to significantly reduce the burden of traumatic brain injury in Cambodia and other developing countries with increasing rates of motorization across the world.  相似文献   

76.
Objective: The footbridge is a vital structure in the road network and a cornerstone among crossing facilities. Yet, it suffers from low usage by pedestrians as they try to cross the street on the level. This study aims to analyze the perceptions of Malaysian pedestrians toward the use of footbridges with the consideration of different factors.

Method: The study was carried out by collecting data from field observation and questionnaire distribution on the street among the public. The data were statistically analyzed by applying multiple linear regression models and a series of chi-square tests.

Results: The study found that the most influential factor cited by pedestrians in decision making regarding using a footbridge is the existence of an escalator. Being in a hurry and the fear of heights were significantly associated with choosing not to use a footbridge. Zebra crossing was chosen as the most favorable type of crossing facility by the majority of respondents. In addition, installation of a fence and barriers was proposed as an effective procedure to prevent jaywalking. To construct new and efficient footbridges in the future, the study suggests consideration of traffic volume, posted speed limit, and the number of lanes, because these are the most influential factors to predict the usage rate.

Conclusions: The study encourages decision makers and stakeholders to consider providing escalators for new footbridges to enhance the safety of pedestrians.  相似文献   

77.
第三产业在北京市的产业格局中占有日益重要的地位,从水资源配置的视角探寻三产结构优化策略具有重要现实意义。采用LMDI分解方法,定量分析北京市第三产业用水结构变化驱动力特征,基于投入产出法计算各行业部门的用水系数,并进行用水特性和行业关联的聚类分析。结果表明,产业规模的快速增长是第三产业用水需求增长的决定性因素,2007-2013年间,累计使总用水量增加了34 476.24万m~3,产业结构效应和技术效应则对用水量的增加起抑制作用,两者分别使用水量减少2 861.29万m~3和21 908.17万m~3,产业结构效应和技术效应对用水的抑制作用不及经济产出效应对用水的拉动作用,最终导致用水量的增长。不同行业之间的用水系数有较大差异,水利、环境和公共设施管理、教育等行业的用水系数相对较大,批发和零售业、金融业的用水系数相对较小,科学研究技术服务和地质勘查等行业的用水乘数较大。第三产业中的高用水行业包括住宿和餐饮业等7个行业部门,潜在高用水行业包括批发和零售业等6个行业;一般用水行业为居民服务和其他服务业。聚类分析结果表明,对于诸如租赁和商务服务业及科学研究技术服务业等感应度系数较大的行业,应优先保障水资源的供给,使用高配额、低水价的管理方式;对于文化体育业等感应度系数较小的行业,可使用低配额、高水价的管理方式,限制用水量;对于配额高且水耗低的产业,可采取水权转让手段,将富余的水权转让给水耗高且产出高的产业。最后,针对研究结果,提出水权交易、技术推广、政策管理与机制构建四方面建议,为第三产业经济增长与用水之间的协调发展提供借鉴。  相似文献   
78.
中国流域水资源综合开发   总被引:4,自引:10,他引:4  
流域是地球陆地表层生态系统最为发达的地域组成单元。作为流域生态系统发育的关键要素,水资源的开发利用决定着包括人文系统在内的整个流域生态系统发育的基本走向和命运。中国是世界上流域水资源开发利用最早的国家之一,目前的综合开发利用程度已经达到较高的水准,且在建的水电大坝工程有数十座。2008 年中国流域水资源综合开发强度已经达到了25.9%,高出全球同期平均水平9 个多百分点。其中淮河、海河和黄河三大流域的开发强度值为最高,水资源的可持续开发能力已荡然无存。受流域水资源结构、需求变化、资源开发环境以及全球气候变暖等因素的共同影响,未来中国流域水资源的综合开发强度应保持在35%左右为宜,其中水资源的开发强度大体可在25%,水电资源的开发强度大体可在50%。  相似文献   
79.
建立了济南市的水资源可持续利用评价指标体系,利用层次分析法等数学方法,对济南市水资源的可持续发展能力进行了研究。结论表明,济南市水资源的可持续利用能力并不高,尤其是环境子系统的得分值处于全省第13位,水资源持续利用将面临较为严峻的挑战。  相似文献   
80.
Objectives: We encountered an unusual facial laceration wound in relation to motorcycle helmet visor use during our clinical practice. We aimed to assess the prevalence of this unusual facial injury among motorcyclists who sustained facial injuries in selected hospitals and to determine the possible mechanism involved.

Methods: We used our prospective cross-sectional substudy involving injured motorcyclists presenting at major trauma hospitals in Southern Klang Valley, Malaysia, between March 2010 and March 2011. of 391 subjects with facial injuries, 2 male motorcyclists sustained this laceration. The wounds were assessed and we believed that each was associated with the helmet visor. One of the visors was collected and the edge was inspected using scanning electron microscopy (SEM).

Results: The prevalence of this unusual injury was 0.51% (95% confidence interval, 0.002–0.012) among motorcyclists who sustained facial injuries. Both cases were involved in a head-on collision with their colliding partners and their helmets were intact throughout the crash. The visor in case 1 was intact, but the visor in case 2 was broken. SEM analysis showed that the visor in case 1 had a potential cutting surface.

We postulated that with helmet rotation in the forward and downward position and with some degree of visor bending or with a dislodged visor, the sharp-edged visor could potentially severely lacerate the face.

Conclusion: This injury affects facial aesthetics and early referral to the facial surgery team is advocated. Documentation of the mechanism of injury, the patient’s helmet and visor is obligatory, so that this information can be delivered to the regional road safety authority for preventive measures.  相似文献   

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