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991.
Online social networks allow users to tag their posts with geographical coordinates collected through the GPS interface of smart phones. The time- and geo-coordinates associated with a sequence of posts/tweets manifest the spatial–temporal movements of people in real life. This paper aims to analyze such movements to discover people and community behavior. To this end, we defined and implemented a novel methodology to mine popular travel routes from geo-tagged posts. Our approach infers interesting locations and frequent travel sequences among these locations in a given geo-spatial region, as shown from the detailed analysis of the collected geo-tagged data.  相似文献   
992.
In this paper, we investigate the impact of flow (operationalized as heightened challenge and skill), engagement, and immersion on learning in game-based learning environments. The data was gathered through a survey from players (N = 173) of two learning games (Quantum Spectre: N = 134 and Spumone: N = 40). The results show that engagement in the game has a clear positive effect on learning, however, we did not find a significant effect between immersion in the game and learning. Challenge of the game had a positive effect on learning both directly and via the increased engagement. Being skilled in the game did not affect learning directly but by increasing engagement in the game. Both the challenge of the game and being skilled in the game had a positive effect on both being engaged and immersed in the game. The challenge in the game was an especially strong predictor of learning outcomes. For the design of educational games, the results suggest that the challenge of the game should be able to keep up with the learners growing abilities and learning in order to endorse continued learning in game-based learning environments.  相似文献   
993.
Abstract

Diflunisal (Dif), Salicylic Acid Derivative, Is A Nonsteroidal Anti-Inflammatory Drug (Nsaid). Preparation Of Dif Suppositories Which Have A Good Bioavailability Was Attempted. Suppositories Containing Dif (250 Mg, Oral Dose) Were Made By The Fusion Method With Pharmasol B-115 (1050 Mg). However, The Dif Suppository Melt Revealed High Viscosity, And The Finding Was Considered To Be Not Acceptable For Manufacture. Accordingly, The Investigation Was Designed To Select An Optimum Additive Which Is Effective To Lower The Viscosity Of The Suppository Melt. The Viscosity Of The Suppository Melt Was Determined By Utilizing Rotating-Cy1inder Viscometer And Then Bingham Viscosity And Yield Value Were Evaluated. As The Results, Some Lecithins And Magnesium Stearate Were Found To Be Effective To Lower The Viscosity Of Dif Suppository Melts. The Theologically Optimum Formulation Contains Lecinol S-10 (4%) And This Formulation Was Evaluated. In The Evaluation, Physical Properties Such As Melting Point, Hardness, Softening Time, Viscosity Etc., Were Measured By Common Methods. Their Properties Were Satisfactory And Were Practically Stable At 5'c. Dif Itself Was Also Stable In Suppository Melts At 60°C.  相似文献   
994.
Abstract

Given that healthcare costs in the U.S. continue to climb, engineering managers can help address this situation by identifying designs for cost savings. Using discrete-event simulation, the layout of four different healthcare clinic scenarios considered in a redesign program named Patient Aligned Care Teams were studied. Model 1 is an existing layout in many clinics and Model 2 is staff-centered, while Models 3 and 4 provide additional space including common hallway(s). Our main conclusion is that Model 4 reduces patient travel distances and average queueing waits, while also providing the best privacy in accordance with HIPAA and the most security for the staff.  相似文献   
995.
This article presents finite element (FE) calculations of stresses in a silo structure caused by the loads exerted by the discharging material. Two different conical hoppers were studied, concentric and eccentric withdrawal. The eccentricity was introduced by the change of the outlet position towards one side of the hopper, and the influence of this modification is presented. The simulation of silo flow with the common Drucker-Prager model for bulk solids was performed in order to obtain the wall pressure distribution. All FE calculations are carried out with aid of the commercial software ABAQUS. Significant differences are found in the hopper-wall stresses between the concentric and eccentric cases. Strong bending actions appear in the eccentric hopper, and they are influenced by stiffness of the hopper/cylinder junction.  相似文献   
996.
997.
《钢铁冶炼》2013,40(4):252-258
Abstract

Since the banking crisis governments have placed renewed emphasis on the importance of manufacturing in providing the basis for a balanced economy. The term High Value Manufacturing (HVM) has been used in the UK to describe manufacturing based industries with a high R&D content and therefore which in turn will support knowledge based job creation into the future. The UK Government has supported the development of a network of manufacturing research centres aimed at providing a step change in research and development activity and impact termed the HVM Catapult. The Advanced Forming Research Centre (AFRC) within the University of Strathclyde is a founder member of the HVM Catapult, with a focus on metal forming and forging technologies.

To outsiders however, forming and forging are established technologies employed within traditional, and in many cases declining, manufacturing environments whose roots can be traced back to the industrial revolution and beyond. It is not surprising, therefore, that the position of metal deformation technologies within the HVM taxonomy is sometimes questioned. This paper aims to address the common arguments which are used to question the position of metal forming and forging within HVM at a general level, and through examples of ongoing work themes with the AFRC.  相似文献   
998.
999.
C?亚历山大教授在其出版的《俄勒冈实验》一书中,以俄勒冈大学为实验母体,界定出一种设计方式,以适用任何社区的总体规划,并归纳为6种主要原则。文章从现实角度出发,针对俄勒冈大学规划现状,提取6种原则中的模式原则并选择其中较为重要的几项模式对其论述进行比较研究,并依照现有实施状况进行一般性评价。对俄勒冈大学规划现状的研究将为我国高校下一阶段的校园规划和校园更新建设提供一定参考价值。  相似文献   
1000.
A comprehensive distributed parameter model for simulating the steady-state performance of a practical horizontal-tube falling-film evaporator has been developed and validated. This model is capable of predicting the distributions of thermal parameters in the tube-side and shell-side, which provide important information of heat and mass exchange processes. The fluid flow and heat transfer characteristics in tubes are analyzed in detail. The computational time is reduced significantly in comparison with the Computational Fluid Dynamics. Based on the numerical results, it is found that the steam is not evenly distributed in the horizontal tubes of each tube pass, which is favorable for parallel channels with uneven heat fluxes. The mass and heat flux of steam are mutually matched, indicating that the self-compensation characteristic appears among the tubes. In addition, the overall heat transfer coefficient reaches the maximum value of about 3300 W/m2 K at the entrance region of each tube pass, and then decreases gradually along the flow direction. As liquid film falls downward from tube to tube, the liquid flow rate of seawater continually decreases from 0.063 kg/ms to 0.04 kg/ms with the corresponding salinity gradually increasing from 36 g/kg to 56 g/kg.  相似文献   
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