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211.
Many studies report an association between outdoor ambient weather and health. Outdoor conditions may be a poor indicator of personal exposure because people spend most of their time indoors. Few studies have examined how indoor conditions relate to outdoor ambient weather. The average indoor temperature, apparent temperature, relative humidity (RH), and absolute humidity (AH) measured in 16 homes in Greater Boston, Massachusetts, from May 2011 to April 2012 was compared to measurements taken at Boston Logan airport. The relationship between indoor and outdoor temperatures is nonlinear. At warmer outdoor temperatures, there is a strong correlation between indoor and outdoor temperature (Pearson correlation coefficient, r = 0.91, slope, β = 0.41), but at cooler temperatures, the association is weak (r = 0.40, β = 0.04). Results were similar for outdoor apparent temperature. The relationships were linear for RH and AH. The correlation for RH was modest (r = 0.55, β = 0.39). Absolute humidity exhibited the strongest indoor‐to‐outdoor correlation (r = 0.96, β = 0.69). Indoor and outdoor temperatures correlate well only at warmer outdoor temperatures. Outdoor RH is a poor indicator of indoor RH, while indoor AH has a strong correlation with outdoor AH year‐round. 相似文献
212.
Phuong D. H. Nguyen Carmine T. Recchiuto Antonio Sgorbissa 《Journal of Intelligent and Robotic Systems》2018,89(1-2):27-49
Multirotors, among all aerial vehicles, are fundamental instruments in many situations, i.e. video recording of sport events, leisure, environmental monitoring before or after a disaster. In particular, in the context of environmental monitoring, the possibility of following a predetermined path while avoiding obstacles is extremely relevant. In this work, we propose a novel method for path definition in presence of obstacles, which describes a curve as the intersection of two surfaces. The planner, based on that path definition along with a Cascaded control architecture and utilizing a nonlinear control technique for both control loops (position and attitude), creates a framework to manipulate the multicopters’ behaviors. The method is demonstrated to be able to generate a safe path taking into account obstacles perceived in real-time and avoids collisions. These algorithms are embedded in a software package to control the flight of a fully autonomous AscTec Firefly hexacopter with two cameras and onboard processing capabilities. 相似文献
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Van Phu Do Phi Luan Nguyen Byung Ryong Lee 《Journal of Mechanical Science and Technology》2014,28(3):1055-1063
This paper describes a new, modified generalized Preisach model for actuators that have severe dead-zone hysteresis, which is mainly observed in rotary SMA actuators. Along with the Preisach model, a new approach of hysteresis modeling and parameter identification using genetic algorithm was proposed. This modeling method achieved significant improvements in both accuracy and computation time. The proposed approach is general; therefore, it can be applied to identify any type of hysteresis. To demonstrate the efficiency of the proposed model, experimental results on hysteresis identification of Rotary SMA Actuator and performance of inverse hysteresis openloop controller are provided and compared. 相似文献
215.
Quyen T. K. Nguyen 《Management International Review》2017,57(3):311-347
The literature on the relationship between the degree of multinationality (M) and performance (P) in the context of multinational enterprises (MNEs) has attracted a large volume of research in the past 50 years. Yet, the theoretical foundations and the empirical conclusions concerning the nature of M–P relationship vary greatly, thus call for a critical review and assessment. We examine 135 articles in 39 leading scholarly journals and classic books published during the period 1960–2015. We use an inductive approach and a qualitative content analysis methodology for our comprehensive and critical review of the literature. We incorporate international business, finance, and accounting perspectives in our analysis. We review the conceptualization and measurement of M, P, the findings on M–P relationships, methodologies, and geographic focus. We identify six key inconsistencies in the existing research, which cause ambiguity in the relevant findings. We make eight recommendations for future research to address these inconsistencies. Thus, our study contributes to the central debate in this research field. 相似文献
216.
The preparation of thioethers by S-alkylation of various thiols with alkyl halides under solvent-free reaction conditions using potassium fluoride on alumina (KF/Al2O3) as a solid catalyst has been investigated in detail with respect to three different modes of reaction activation (ultrasound irradiation, microwave irradiation, and conventional heating) for obtaining maximum yield of the thioether. The importance of KF/Al2O3 as a particularly efficient catalyst was corroborated for all three modes of reaction activation, although the reaction time was found to be strongly dependent on the mode of activation. The yield of the thioethers was also found to depend on the amount of the solid catalyst relative to the equimolar amounts of the two reactants. 相似文献
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Dam development is widespread in central Vietnam. Interviews were conducted with households that had been resettled and those that had not to determine the type of agricultural livelihoods that were re-established nine years after resettlement due to the Ta Trach reservoir project. Results showed that resettled households, despite having more forest land, were economically worse off compared with households that were not moved. This discrepancy between households was attributed to less arable land allocated to resettled households. The provision of good-quality land, able to grow crops and food trees, was essential if households were to re-establish a comparable agriculturally based livelihood. 相似文献
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