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61.
机车司机行车安全监控系统应用研究 总被引:3,自引:0,他引:3
宋志雄 《中国安全科学学报》2005,15(10):110-112
分析铁路行车安全监控系统的复杂性和现状;设计分局机车司机行车安全监控系统和数据流向;研制车载的机车司机工作状态实时监督系统;采用视频监控、图像处理技术以及人脸识别技术对机车司机工作状态进行识别并实时报警。经过实验证明:对司机长时间离开座位、睡眠和呆木状态有较高的识别率;同时对司机工作状态的图像信号进行压缩储存;管理人员可以回放检查。采用CDMA技术设计了地面对机车司机工作状态的视频监控子系统,可以把司机的工作状态图像及时传送到车站或调度中心。实际线路实验表明,该系统可以大大提高司机工作的安全性。 相似文献
62.
城市防空和灾情报警防御系统研究 总被引:1,自引:0,他引:1
近年来 ,城市防空和灾情报警防御系统作为一种重要的城市防御灾情措施 ,特别是应对各种恐怖破坏活动和地域灾害的突然发生 ,以及未来战争的防御需求等灾情 ,已受到人们高度重视。笔者针对我国城市防空和灾情报警防御系统的实际现状 ,提出了我国城市防空和灾情报警防御系统的建设初步思想 ,并从系统的组织结构、功能原理、救援组织等几方面进行了描述 ,对提高城市的防御能力、避免灾难的发生 ,具有重要的指导作用 相似文献
63.
A number of inexact programming methods have been developed for municipal solid waste management under uncertainty. However, most of them do not allow the parameters in the objective and constraints of a programming problem to be functional intervals (i.e., the lower and upper bounds of the intervals are functions of impact factors). In this study, a flexible interval mixed-integer bi-infinite programming (FIMIBIP) method is developed in response to the above concern. A case study is also conducted; the solutions are then compared with those obtained from interval mixed-integer bi-infinite programming (IMIBIP) and fuzzy interval mixed-integer programming (FIMIP) methods. It is indicated that the solutions through FIMIBIP can provide decision support for cost-effectively diverting municipal solid waste, and for sizing, timing and siting the facilities’ expansion during the entire planning horizon. These schemes are more flexible than those identified through IMIBIP since the tolerance intervals are introduced to measure the level of constraints satisfaction. The FIMIBIP schemes may also be robust since the solutions are “globally-optimal” under all scenarios caused by the fluctuation of gas/energy prices, while the conventional ones are merely “locally-optimal” under a certain scenario. 相似文献
64.
Marine Protected Areas (MPAs) have been hailed worldwide as vehicles toward sustainable development (SD) in coastal zones.
The prominent model by which MPAs operate is through a comanagement approach, a shift from traditional top-down management.
This paradigm shift must be reviewed continuously to evaluate its social and ecological impacts, thereby allowing adaptive
management. We evaluated the perceived impacts of the Cogtong Bay Mangrove Rehabilitation Project (CBMRP; Philippines) by
using 12 perception indicators categorized into 3 comanagement impact criteria (equity, efficiency, and sustainability). We
also collected 16 contextual attributes of each respondent to determine the correlates of perceived impacts. Our results showed
that there were significant improvements in all indicators under the efficiency criterion but mixed impacts in the equity
and sustainability criteria. Access to resource and household income (equity) and fisheries abundance (sustainability) were
perceived to have decreased during the last 15 years and were not expected to improve in the future. Stepwise multiple regression
analysis showed that the asymmetries of the perceived impacts of the CBMRP were principally caused by disparities in perceptions
by gender and by location (Candijay and Mabini). This highlighted the importance of cross-scale institutional linkages between
Cogtong Bay municipalities to systematically address baywide management issues. Our results further demonstrated the necessity
of integrating gender issues into the evaluation of MPA impacts to ensure a robust evaluation. Finally, we recommend that
a rigorous evaluation of MPAs using a common set of impact indicators should be encouraged to allow comparison of studies
both spatially and temporally. 相似文献
65.
66.
The work is devoted to the investigation of nonlinear singular ecological models with initial functional conditions and determination of solutions of problems, which are connected with these models. It is also considered some of its applications in field of ecological modelling under formulation and investigation of the so-called keeping and protection problems. We shall investigate nonlinear models that are described with the help of partial differential equation of first and second orders. Solutions of linear and some singular nonlinear problems with functional initial conditions are obtained in the form depending from initial parameters. 相似文献
67.
68.
Within-nest temporal polyethism in the honey bee 总被引:1,自引:1,他引:0
Brian R. Johnson 《Behavioral ecology and sociobiology》2008,62(5):777-784
A well-regulated division of labor has been one of the core adaptations leading to the success of the social insects. Honeybee
division of labor has been classically viewed as a sequence of age-related changes in task performance. Kolmes questioned
this view arguing that his studies did not support the existence of any age-related within-nest specialization. To resolve
this controversy, Kolmes and Seeley conducted a joint study with mixed results. They found support for a cell cleaning caste,
but diverged on whether their results supported distinct nursing and middle age castes. In this paper, I follow up on their
work to resolve the question of caste number in within-nest honey bees. To determine whether nurses (typically aged 4–12 days)
and middle-aged bees (aged 12–20 days) have distinct task repertoires, I conducted focal animal observations on a large number
of workers in both age groups working within the same nests at the same time. The results support their being two castes of
within-nest bees. Young bees specialized on brood care tasks, while middle-aged bees specialized on nectar processing and
nest maintenance. Middle-aged bees were observed caring for brood in less than 1% of the observations. Moreover, both castes
exhibited movement patterns that correspond to the traditional view that nurses stay within the broodnest, while middle-aged
bees move around a great deal in search of work throughout the nest. A review of studies conducted since the debate of Seeley
and Kolmes supports the reliability of these results. This work has relevance for proximate models of temporal polyethism,
as it is often assumed by such models that there is only one within-nest caste in the honeybee. 相似文献
69.
Anna Dornhaus Jo-Anne Holley Victoria G. Pook Gemma Worswick Nigel R. Franks 《Behavioral ecology and sociobiology》2008,63(1):43-51
Here, we study distribution of workload and its relationship to colony size among worker ants of Temnothorax albipennis, in the context of colony emigrations. We find that one major aspect of workload, number of items transported by each worker,
was more evenly distributed in larger colonies. By contrast, in small colonies, a small number of individuals perform most
of the work in this task (in one colony, a single ant transported 57% of all items moved in the emigration). Transporters
in small colonies carried more items to the new nest per individual and achieved a higher overall efficiency in transport
(more items moved per transporter and unit time). Our results suggest that small colonies may be extremely dependent on a
few key individuals. In studying colony organisation and division of labour, the amount of work performed by each individual,
not just task repertoire (which tasks are performed at all), should be taken into account. 相似文献
70.
Functional agrobiodiversity (FAB) has severely declined during the last decades. Current efforts to reinforce FAB are mainly focused on single-actor, parcel-based measures, whereas multi-actor landscape approaches are supposed to be more effective. In this paper, we propose a social–ecological framework that structures how different land users at both the parcel and landscape level interact with FAB as a natural resource. Furthermore, we introduce 1 m2 FAB gardens as an interactive multipurpose measurement tool to gather data on ecosystem services in collaboration with land users. The presented action research approach provides new insights on motivations and interests of different land users in FAB and how knowledge exchange can result in a higher motivation to invest in FAB. Using a case study in Flanders, we illustrate the FAB-garden concept and highlight its strengths and necessary considerations to properly complement other research approaches in this social–ecological system.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01382-0) contains supplementary material, which is available to authorized users. 相似文献