Evaluation of Using the Bootstrap Procedure to Estimate the Population Variance

The bootstrap procedure is widely used in nonparametric statistics to generate an empirical sampling distribution from a given sample data set for a statistic of interest. Generally, the results are good for location parameters such as population mean, median, and even for estimating a population correlation. However, the results for a population variance, which is a spread parameter, are not as good due to the resampling nature of the bootstrap method. Bootstrap samples are constructed using sampling with replacement; consequently, groups of observations with zero variance manifest in these samples. As a result, a bootstrap variance estimator will carry a bias to the low side. This work will attempt to demonstrate the bias issue with simulations, as well as explore possible approaches to correct for any such bias. In addition, these approaches will be evaluated for more general performance through simulations

POSITIVISM OF ERNST MACH: VLADIMIR LENIN’S CRITIQUE FROM PHILOSOPHICAL WORK MATERIALISM AND EMPIRIO–CRITICISM

Philosophical views of Ernst Mach represent the second-generation of Positivism. Developed by the end of the 19th century, Mach’s positivism associated with the turning point of Scientific Revolution which marked the emergence of modern science. From Ernst Mach’s viewpoint, philosophy was intertwined with natural sciences and turned into its core concepts. He advocated the absolute role of sensation, focused on “the principle of economy of thought” definition; opposed atomism and metaphysics. In the philosophical work “Materialism and Empirio-criticism”, Vladimir Lenin severely criticized Ernst Mach’s position of subjective idealism and philosophical realists.  Article visualizations

Modelling of a vacuum consolidation project in Vietnam

Ground improvement technique by prefabricated vertical drain (PVD) in combination with vacuum preloading is widely used to facilitate consolidation process and reduce residual settlement. However, this technique seem hardly be estimated by both analytical method and numerical method because it has complex boundary conditions (such as vacuum pressure changing with time). Moreover, lateral displacements caused by this technique are also significant problem. Numerical modelling may be an effective design tool to estimate behavior of soft soil treated by this method, however it needs to have a proper calibration of input parameters. This paper introduces a matching scheme for selection of soil/drain properties in analytical solution and numerical modelling (axisymmetric and plane strain conditions) of a ground improvement project by using Prefabricated Vertical Drains (PVD) in combination with vacuum and surcharge preloading. In-situ monitoring data from a case history of a road construction project in Vietnam was adopted in the back-analysis. Analytical solution and axisymmetric analysis can approximate well the field data meanwhile the horizontal permeability need to be adjusted in plane strain scenario to achieve good agreement. In addition, the influence zone of the ground treatment was examined. The residual settlement was investigated to justify the long-term settlement in compliance with the design code. Moreover, the degree of consolidation of non-PVD sub-layers was also studied by means of two different approaches

Développement d’un système de microscopie pour la détection en temps résolu de la fluorescence de complexes macromoléculaires mixtes gadolinium/terbium destinés à l’imagerie bimodale de l’atherothrombose

We developed a fluorescence imaging microscope system intended for localizing and evaluating its concentration with in arteries slices of a macromolecular (P717) Gd-based MRIcontrast agent used for the visualization of atherosclerotic lesions. As the contrast agent is not initially fluorescent, we modified the agent which is now partially fitted with Tb ions, while preserving its chemical characteristics. A long fluorescence emission time constant enables usto have a suitable signal to noise ratio, despite a low intensity, using pulsed illumination and time gated imaging after the other sources of fluorescence have decayed.The excitation source, on top of the inverted microscope, is a laser diode emitting at 371nm. The fluorescence signal is imaged on an ICCD camera. The fluorescence spectrum is acquired too, to positively insure that the signal really comes from the intended contrast agent. A microcontroller synchronizes electrical gating of the ICCD camera, of the laser pulse and generally controls automatically all parts of the measurement process. For tissue identification, we acquire a “natural image” using the standard halogen lamp of themicroscope. This image is synthesized by the use of the combination of three successive images taken with the three fundamental colors. Then our software assembles the color and fluorescence images.First images of rat arteries show that the contrast agent is indeed localized on specific regions of the tissues. We now have a new tool which allows us to understand and optimize the MRI contrast agent.Nous avons développé un microscope d’imagerie de fluorescence destiné à localiser,et à évaluer la concentration, d’un agent de contraste IRM macromoléculaire (P717) incluant du Gd, destiné à identifier les lésions athérosclérotiques. Comme l’agent de contraste n’est pas naturellement fluorescent, nous l’avons modifié en substituant des ions Tb aux ions Gd,ce qui ne modifie pas ses propriétés chimiques vis-à-vis de l’artère. Comme sa constante de temps est très supérieure à celle des autres sources de fluorescence, nous obtenons un bon rapport signal sur bruit, malgré une faible émission, par une technique de résolution temporelle.La source d’excitation, sur le microscope inversé, est une diode laser émettant à 371nm, le capteur est une caméra ICCD. Nous mesurons aussi le spectre de la fluorescence pour nous assurer que le signal provient réellement de l’agent étudié. Un microcontrôleur permet de gérer automatiquement la synchronisation de toutes les parties du système. Pour l’identification des tissus par un anatomo-pathologiste, nous prenons aussi une photo en« couleurs naturelles » en prenant successivement trois images aux trois couleurs fondamentales. Ensuite, notre logiciel assemble toutes les images en couleurs et en fluorescence.Les premières images que nous avons prises sur des artères de rat nous prouvent que l’agent de contraste est effectivement localisé dans des régions spécifiques. Nous disposons maintenant d’un outil nous permettant de comprendre l’attachement d’un agent de contraste IRM sur une artère et qui nous permettra d’optimiser cet agent

視覚刺激と回転性前庭刺激との不一致が大脳皮質血流応答に及ぼす影響- fNIRSによる研究

富山大学・富医薬博甲第325号・NGUYEN TRONG NGHIA・2020/03/24公表論文Front. Hum. Neurosci. 14:125. https://doi.org/10.3389/fnhum.2020.00125富山大

Issues on applying continuous integration in mobile application development : a case study

In recent years, the mobile application market has challenged developers to develop and release quality applications rapidly. This fierce competition requires application development to be conducted in an efficient way. Continuous integration (CI) is a software development practice which focuses on automation. Applying CI practice into the mobile application development properly helps developers have an effective application development. By conducting case study on the project Seutuhaku at Observis Oy, the author shows how CI is applied to mobile application development. The case study design and the steps of applying are discussed in this thesis. The results of the case study highlight the advantages of the new development practice when compared with the previous development practice. Moreover, issues of applying the new development practice such as the vision of project leaders and the commitments of developers are listed and discussed. It is to be hoped that the results of the case study are able to help other mobile application developers pay attention to CI and apply it appropriately

Simulation of bearing capacity of pile in crushable soil

Crushable soils such as volcanic soils, carbonate sand or decomposed granites whose grains are easily break under foundation pressure, especially, large magnitude of stresses under pile tips. When the grains are crushed, particle size distribution (PSD) varies followed by higher compressibility of these soils. Pile foundation's settlement in crushable soils tends to be increased. Nonetheless, design code for bearing capacity of pile in crushable soil is still unavailable leading to a lot of difficulties for engineers to have an appropriate foundation design. This paper introduces a constitutive model for soils which takes account of the breakage mechanics including the evolutions of PSD and the compressibility due to grain crushing. The model is implemented in a finite element code to simulate pile penetration in crushable soil. Finally, the particle breakage around pile's tip is examined

Mobile education in autopsy conferences of pathology: presentation of complex cases

BACKGROUND: MeduMobile was a project to develop and evaluate learning scenarios for medical students and teachers by use of video communication and notebooks. Its core part was assigned to various medical routines, conferences or meetings such as doctor-patient bedside conversation. These were filmed by video teams and broadcasted live via the WLAN of the Charité campus to course participating students. One type of the learning arrangements was the autopsy conference as an on-call scenario. MATERIALS AND METHODS: The MeduMobile project consisted of two main compartments: the regular seminar event which took place every week or month, and the on-call event. For an on-call event the students were informed two hours before the lesson's start. A mobile video team organised the video conference via a specific MeduMobile seminar system. This software offered the students to log. The MeduMobile seminar system is based on the Windows operating system and realises an extended video communication via WLAN. Thirteen access points were implemented at the Charité Campus Virchow Klinikum and Campus Mitte. A questionnaire was developed to investigate in the response and learning effect of the mobile seminar system. RESULTS: During the MeduMobile project 42 video conferences with (cumulative) 145 participating students took place. Four autopsy conferences could be organised as on-call scenarios within this project. A prospective, not randomised follow-up study was included 25 students of the 1(st )– 6(th )clinical semester. According to the answers, professional reasoning, professional performance, sustainability, and the complexity were broadly accepted by the students. DISCUSSION: In principle, the MeduMobile realised an interdisciplinary case presentation using video conference and web page. The evaluation indicates a high acception of such complex case presentation with multidisciplinary settings. The use of the notebooks in mobile learning enables an interconnective training and promotes a complex learning

Advanced Metering Infrastructure Based on Smart Meters in Smart Grid

Due to lack of situational awareness, automated analysis, poor visibility, and mechanical switches, today\u27s electric power grid has been aging and ill‐suited to the demand for electricity, which has gradually increased, in the twenty‐first century. Besides, the global climate change and the greenhouse gas emissions on the Earth caused by the electricity industries, the growing population, one‐way communication, equipment failures, energy storage problems, the capacity limitations of electricity generation, decrease in fossil fuels, and resilience problems put more stress on the existing power grid. Consequently, the smart grid (SG) has emerged to address these challenges. To realize the SG, an advanced metering infrastructure (AMI) based on smart meters is the most important key