A plug-and-play ripple mitigation approach for DC-links in hybrid systems

© 2016 IEEE.In this paper, a plug-and-play ripple mitigation technique is proposed. It requires only the sensing of the DC-link voltage and can operate fully independently to remove the low-frequency voltage ripple. The proposed technique is nonintrusive to the existing hardware and enables hot-swap operation without disrupting the normal functionality of the existing power system. It is user-friendly, modular and suitable for plug-and-play operation. The experimental results demonstrate the effectiveness of the ripple-mitigation capability of the proposed device. The DC-link voltage ripple in a 110 W miniature hybrid system comprising an AC/DC converter and two resistive loads is shown to be significantly reduced from 61 V to only 3.3 V. Moreover, it is shown that with the proposed device, the system reliability has been improved by alleviating the components' thermal stresses

Decline in Telomere Length by Age and Effect Modification by Gender, Allostatic Load and Comorbidities in National Health and Nutrition Examination Survey (1999-2002)

Background: This study aims to assess the decline in telomere length (TL) with age and evaluate effect modification by gender, chronic stress, and comorbidity in a representative sample of the US population. Methods: Cross-sectional data on 7826 adults with a TL measurement, were included from the National Health and Nutrition Examination Survey, years 1999–2002. The population rate of decline in TL across 10-year age categories was estimated using crude and adjusted regression. Results: In an adjusted model, the population rate of decline in TL with age was consistent and linear for only three age categories: 20–29 (β = -0.0172, 95% CI: -0.0342, -0.0002), 50–59 (β = -0.0182, 95% CI: -0.0311, -0.0054) and 70–79 (β = -0.0170, 95% CI: -0.0329, -0.0011) years. The population rate of decline in TL with age was significantly greater for males and those with high allostatic load and a history of comorbidities. When the population rate of decline in TL was analyzed by gender in 10-year age bins, a fairly consistent yet statistically non-significant decline for males was observed; however, a trough in the rate was observed for females in the age categories 20–29 years (β = -0.0284, 95% CI: -0.0464, -0.0103) and 50–59 years (β = -0.0211, 95% CI: -0.0391, -0.0032). To further elucidate the gender difference observed in the primary analyses, secondary analyses were conducted with reproductive and hormonal status; a significant inverse association was found between TL and parity, menopause, and age at menopause. Conclusions: TL was shorter with increasing age and this decline was modified by gender, chronic stress and comorbidities; individuals with chronic morbidity and/or chronic stress and females in their twenties and fifties experienced greater decline. Female reproductive factors, i.e., parity and menopause, were associated with TL

Isolation & Characterization of Bacteria in the Built Environment: Measuring The Effect of Pharmaceuticals on Growth

This work reports the isolation and characterization of bacteria from the built environment at Gettysburg College in Gettysburg, PA. Surfaces of a water fountain on campus were swabbed and serially streaked to isolate multiple bacteria on R2A agar. Following multiple rounds of growth, the unknown microbial candidates were narrowed to two visibly­distinct organisms. Morphological characterization and phylogenetic identification based on 16S rDNA sequencing revealed that the isolates were Chryseobactierum hispalense and Microbacterium maritypicum. We report synergistic biofilm formation between Chryseobactierum hispalense and Microbacterium maritypicum. The contamination of drinking water with varying levels of personal care products and pharmaceuticals (PCPPs) is well documented. Additionally, these environmental pollutants and their derivatives affect aquatic life, as illustrated with effect of the antidepressant fluoxetine on mudsnails. To determine if previously reported contaminants affect freshwater bacteria, we assessed both planktonic growth and biofilm formation following exposure to nalidixic acid (non­fluorinated quinolone antibiotic), diphenhydramine (over­the­counter drug Benadryl), and fluoxetine (Prozac)

Logarithmic interaction under periodic boundary conditions: Closed form formulas for energy and forces

A method is given to obtain closed form formulas for the energy and forces for an aggregate of charges interacting via a logarithmic interaction under periodic boundary conditions. The work done here is a generalization of Glasser's results [M. L. Glasser, J. Math. Phys. 15, 188 (1974)] and is obtained with a different and simpler method than that by Stremler [M. A. Stremler, J. Math. Phys. 45, 3584 (2004)]. The simplicity of the formulas derived here makes them extremely convenient in a computer simulation

Rancang Bangun Sistem Informasi Inventaris Berbasis Multimedia Akses Online

Inventory management manually inhibit the performance of institutions.This research was aimed at developing a multimedia-based inventory information system program that can meet users\u27 specific needs. The information system program was developed on multimedia basis to produce output of inventory data in the form of 3D texts and visuals that are accessible online to multi users. The development research adopted the SLDC method. Initially, the program was developed using XAMPP as the local web server that includes Apache Web Server, PHP Script Language, MySQL Database, and phpMyAdmin Database Manager.Data were collected through observation, interviews and document study of educational institutions and public institutions. The program\u27s feasibility was tested by Stub Testing, Unit Testing, Black Box Testing, and White Box Testing, as well as Integration Testing. Its execution includes access modules with system login as the main access gate. The program database scheme includes (1) System Login, (2) Menu Manager,(3) Data Entry, (4) Circulation or Transaction, (5) Maintenance, and (6) Report. The information system model is capable of presenting information in the form of texts or images, and the data input uses the barcode system.The system provides access to a menu of top-down and bottom-up to facilitate the use and meet the specific needs and complete. The system was designed as an open source program, so it is open to development for studio or workshopand library information system

Selection the Colour of Object with Conveyor Used Robotic Arm

Conveyor konvensional pada saat ini hanya memindahkan barang saja, tidak bisa mendeteksi warna benda dan perlu tenaga manusia untuk menyortir benda, oleh karena alasan itu, maka dirancang suatu conveyor otomatis. Disebut conveyor otomatis karena conveyor tersebut diletakkan sebuah pendeteksi warna untuk mendeteksi jenis warna benda. Conveyor ini dirancang untuk mendistribusikan benda kayu berukuran 6cm x 6cm x 6cm dengan penggerak motor DC 24 VDC dan pendeteksi warna TCS230 dipasang untuk membedakan warna benda. Conveyor dengan sensor warna juga dilengkapi dengan lengan robot yang diprogram sebagai alat penyortir benda, agar tidak bercampurnya jenis warna berbeda.Hasil penelitian menunjukkan bahwa conveyor dengan sensor warna ini mampu mendeteksi warna dengan sensor warna TCS230 dengan teliti sesuai dengan program yang dimasukan pada mikrokontroler dan robot lengan mampu menyortir dan menempatkan benda sesuai dengan urutan warnanya

Effects of alarms on control of robot teams

Annunciator driven supervisory control (ADSC) is a widely used technique for directing human attention to control systems otherwise beyond their capabilities. ADSC requires associating abnormal parameter values with alarms in such a way that operator attention can be directed toward the involved subsystems or conditions. This is hard to achieve in multirobot control because it is difficult to distinguish abnormal conditions for states of a robot team. For largely independent tasks such as foraging, however, self-reflection can serve as a basis for alerting the operator to abnormalities of individual robots. While the search for targets remains unalarmed the resulting system approximates ADSC. The described experiment compares a control condition in which operators perform a multirobot urban search and rescue (USAR) task without alarms with ADSC (freely annunciated) and with a decision aid that limits operator workload by showing only the top alarm. No differences were found in area searched or victims found, however, operators in the freely annunciated condition were faster in detecting both the annunciated failures and victims entering their cameras' fields of view. Copyright 2011 by Human Factors and Ergonomics Society, Inc. All rights reserved

A design methodology for smart LED lighting systems powered by weakly regulated renewable power grids

The increasing use of intermittent renewable energy sources to decarbonize electric power generation is expected to introduce dynamic instability to the mains. This situation is of particular concern for mini-grids or isolated grids in which wind and/or solar power sources are the dominant or the sole power sources. In this paper, we utilize the photo-electro-thermal theory to develop a design methodology for LED lighting systems for weakly regulated voltage sources, with the objectives of minimizing the fluctuation of the human luminous perception and adopting reliable LED driver with long lifetime and robustness against extreme weather conditions. The proposed LED system, practically verified in a 10 kVA small power grid driven by an ac voltage source and a wind energy simulator, can be considered as a smart load with its load demand following the power generation. A typical swing of 40 V in the mains will cause only 15% actual light variation in a 132 W LED system when compared with 40% change in 150 W high-pressure-sodium lamp system. The design methodology enables future large-scale LED systems to be designed as a new generation of smart loads that can adapt to the voltage and power fluctuations arising from the intermittent nature of renewable energy sources. © 2011 IEEE.published_or_final_versio

An engineered cardiac reporter cell line identifies human embryonic stem cell-derived myocardial precursors.

Unlike some organs, the heart is unable to repair itself after injury. Human embryonic stem cells (hESCs) grow and divide indefinitely while maintaining the potential to develop into many tissues of the body. As such, they provide an unprecedented opportunity to treat human diseases characterized by tissue loss. We have identified early myocardial precursors derived from hESCs (hMPs) using an α-myosin heavy chain (αMHC)-GFP reporter line. We have demonstrated by immunocytochemistry and quantitative real-time PCR (qPCR) that reporter activation is restricted to hESC-derived cardiomyocytes (CMs) differentiated in vitro, and that hMPs give rise exclusively to muscle in an in vivo teratoma formation assay. We also demonstrate that the reporter does not interfere with hESC genomic stability. Importantly, we show that hMPs give rise to atrial, ventricular and specialized conduction CM subtypes by qPCR and microelectrode array analysis. Expression profiling of hMPs over the course of differentiation implicate Wnt and transforming growth factor-β signaling pathways in CM development. The identification of hMPs using this αMHC-GFP reporter line will provide important insight into the pathways regulating human myocardial development, and may provide a novel therapeutic reagent for the treatment of cardiac disease