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81.
ABSTRACT

This paper proposes the multiple-hypotheses image segmentation and feed-forward neural network classifier for food recognition to improve the performance. Initially, the food or meal image is given as input. Then, the segmentation is applied to identify the regions, where a particular food item is located using salient region detection, multi-scale segmentation, and fast rejection. Then, the features of every food item are extracted by the global feature and local feature extraction. After the features are obtained, the classification is performed for each segmented region using a feed-forward neural network model. Finally, the calorie value is computed with the aid of (i) food volume and (ii) calorie and nutrition measure based on mass value. The experimental results and performance evaluation are validated. The outcome of the proposed method attains 0.947 for Macro Average Accuracy (MAA) and 0.959 for Standard Accuracy (SA), which provides better classification performance.  相似文献   
82.
我国煤矿生产事故频发,顶板垮落、瓦斯爆炸、机电事故、突水、矿井火灾、放炮等隐患时刻影响着煤矿安全生产,当前矿井开采以井下开采为主,井下开采存在技术要求高、开采难度大的问题,导致煤矿事故发生数和死亡人数相对其他行业居于首位。因此,为了深入研究煤矿事故发生原因和规律,统计了近10 a我国煤矿事故数据,找出当前矿山开采存在的各种安全问题,针对存在的问题提出解决措施,对预防及应对煤矿安全问题具有重要意义。  相似文献   
83.
何彦奇 《中州煤炭》2020,(4):52-55,60
为了给辉县景区减灾防灾提供地质依据,根据实际工程概况,研究了辉县部分景区地质灾害危险性预测评估及防治措施,预测评估了工程建设中、建设后可能引发或加剧地质灾害危险性,建设工程自身可能遭受已存在地质灾害危险性;评估了地质灾害危险性综合分区以及根据地质灾害危险性、防治难度和防治效益,对评估区适宜性作出评价,提出了防治地质灾害的措施和建议。  相似文献   
84.
白仁喜 《陕西煤炭》2020,39(2):176-178
制定供电过程中消除安全隐患的针对性措施,可以为矿井安全生产提供必要保障。为探究煤矿供电管理中安全隐患的具体分析方法,首先介绍“人机环管”管理体系的建立过程和核心内容,接着以“人机环管”的管理方法分析了供电管理中的普遍问题。在分析供电管理中的具体问题时,分别得出了“人”“机”“环”“管”4方面的具体措施。分析认为,“人机环管”方法可以有效查找出存在的安全隐患,进而保证煤矿供电系统的安全可靠。  相似文献   
85.
屈持  王海清  刘建利  姚竣瀚 《化工进展》2020,39(11):4384-4390
在石化安全关键设备寿命截尾数据的可靠性评估过程中,为避免传统可靠性评估方法未考虑维修对故障间隔时间的影响,以及中值填充法误差较大的缺点,本文提出了一种逆变换区间截尾数据填充方法。首先,在可修系统基于最小维修的假设下,通过非齐次泊松过程描述系统的故障趋势,利用逆变换填充得到监测区间的缺失数据;随后根据蒙特卡罗期望最大化算法,获得填充数据的参数估计值。通过蜡油加氢装置紧急泄压阀的案例分析,该算法能够很好地融合已有数据,得到的形状参数估计值偏差与中值填充法相比缩小4%以上,从而验证了该算法的有效性;这有助于安全关键设备的定量化完整性管理,保障石化装置平稳运行。  相似文献   
86.
The aim of this study was to evaluate the dietary exposure to fumonisin B1 (FB1) through determination of residual FB1 in hair and corn products consumed by 56 volunteers from Pirassununga and Erval Velho, Brazil. Data from FB1 analyses in corn products and a Food Frequency Questionnaire (FFQ) were used for estimating the mean probable daily intake (PDIM) for FB1. FB1 was detected in 4 human hair samples (7.2%), at a mean level of 21.3 ± 12.1 ng g−1. The mean FB1 level found in corn products was 360.4 ± 555.1 μg kg−1. The PDIM value of FB1 in volunteers was 159 ± 47 ng kg−1 body weight day−1 which represents 7.9% of the provisional maximum tolerable daily intake (PMTDI) recommended for fumonisins. The FB1 levels found in human hair samples from each volunteer were associated with their individual PDI of FB1, indicating that exposure to FB1 in the sample studied do not represent a health concern. This is the first report on the incidence of FB1 in individual human hair in Brazil.  相似文献   
87.
通过对矿山救援现状的了解,发现其中存在的问题和隐患,并制定有效且适用的维护救护队员安全的解决措施,提高救援安全性,维护救援队员的人身安全,并为救援及相关人员提供参考和借鉴。  相似文献   
88.
The development of distributed energy systems has important environmental, social and economic implications. Local decision-making processes must be guided by a careful evaluation of the sustainability of production chains and alternative choices. The aim of this study is to explore if and how an integrated assessment can quantify the extent to which bioenergy supply chain development contributes to rural development and energy policy objectives. We applied a Sustainability Impact Assessment (SIA) for local bioenergy development in the alpine area of Lake Como (Italy). We modeled the local bioenergy chain in 2008 and eleven scenarios considering different biomass utilizations, mechanization levels, combustion technologies, and subsidies schemes at 2020. We calculated economic, social and environmental indicators. We interpret and discuss the scenario analysis in order to support the bioenergy planning under the light of its implications for the different policy aims and concerns.  相似文献   
89.
This study presents a methodology to assess suitability of a site for small scale concentrated solar power (CSP) systems for its energy conversion efficiency and make‐up water requirement. Energy conversion efficiency of CSPs relies not only on the level of direct solar radiation but also on the performance of the cooling system. Regions with high solar potential have to deal with heat rejection at elevated temperatures which causes reduced energy conversion efficiencies due to high condenser temperatures. It is desirable to utilize wet cooling systems as they can achieve temperatures lower than the dry bulb temperature by evaporative cooling. On the other hand, such regions usually lack water resources which deteriorate the sustainable nature of CSP applications. This study combines various available models for both solar resource estimation and cooling systems' performance considering (i) the influence of ambient temperatures, and (ii) the influence of humidity levels. These models are integrated together to analyze the use of dry or wet cooling systems in terms of overall energy output and water consumption at a selected site in northern Cyprus. The model inputs consist of only annual hourly surface weather data and the location of the site of interest. The results show that dry cooling unit at northern Cyprus is capable of saving water about 18.7 ton/MWh while it produces 27% less energy compared to the wet cooling alternative for the representative annual weather data. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
90.
This study proposes an analytical and flexible terrain risk assessment method for military surveillance applications for mobile assets. Considering the risk as the degree of possibility of insurgent presence, the assessment method offers an efficient evaluation of risk in the surrounding terrain for military combat operating posts or observation posts. The method is designed for unmanned aerial vehicles as the surveillance assets of choice to improve the effectiveness of their use. Starting with the area map and geographical data, the target terrain is first digitized for space representation. Then the data of nine geographical parameters are used to formulate five contributing risk factors. These factors are incorporated in an analytical framework to generate a composite map with risk scores that reveal the potential high-risk spots in the terrain. The proposed method is also applied to a real-life case study of COP Kahler in Afghanistan, which was a target for insurgent attacks in 2008. The results confirm that when evaluated with the developed method, the region that the insurgents used to approach COP Kahler has high concentration of high-risk cells.  相似文献   
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