scholarly journals Overview on Design Considerations for Development of Disposable Microbioreactor Prototypes

2012 ◽  
pp. 53-60 ◽  
Author(s):  
Muhd Nazrul Hisham Zainal Alam ◽  
Krist V. Gernaey
Keyword(s):  
Feeding Strategy ◽  
Optical Measurements ◽  
Detection Methods ◽  
Physical Parameters ◽  
Operating Feature ◽  
Design Considerations ◽  
Strategy Process ◽  
Bioreactor System ◽  
Reactor Operating ◽  
Important Design

Microbioreactors are a miniaturized scale bioreactor system normally designed for bioprocess development. Such a microbioreactor design offer a new platform in carrying out cheap fermentation experiments under well controlled conditions – comparable to that of typical bench scale bioreactors. Additionally, by adapting polymer technology, microbioreactor can for example be made disposable. Thus, eliminates the need for cleaning of the reactor at the end of every experiment. Since typical working volumes of microbioreactors are less than 1 mL, this furthermore reduces substrate and utility consumption per experiment. Additionally, often a microbioreactor system is interfaced with optical measurements to acquire a real-time experimental data and thus, increases the amount of information gained per experiment. To design a microbioreactor system, one must consider the design of the entire system that drives the reactor and not just restrict the design only to the mechanical aspects of the reactor. In this paper, important design considerations as well as technical challenges for establishment of a microbioreactor to facilitate a typical aerobic fermentation processes are discussed. These include reactor operating feature and size, reactor mechanics (materials, fabrications, and mixing), reactor fluidics (connections, aeration, evaporation and feeding strategy), process control of physical parameters (temperature, pH, and dissolved oxygen level) and detection methods for measuring the cells concentration. Mikrobioreaktor adalah sistem bioreaktor skala minatur yang kebiasaannya direkabentuk untuk pembangunan bioproses. Rekabentuk mikrobioreactor seperti ini memberikan pendekatan yang baru dalam menjalankan eksperimen-eksperimen fermentasi berkos rendah pada keadaan terkawal – menghampiri pada keadaan yang secara tipikalnya diperolehi di bioreaktor skala makmal. Malah, dengan mengadaptasikan teknologi polimer, mikrobioreaktor boleh dijadikan sebagai bahan pakai-buang. Secara tidak langsung ini membasmi langkah yang diperlukan untuk pembersihan reaktor di akhir setiap eksperimen. Oleh sebab isipadu kerja yang tipikal bagi mikrobioreaktor adalah kurang dari 1 mL, ini akan mengurangkan penggunaan bahan dan utiliti bagi setiap eksperimen. Sistem mikrobioreaktor juga sering dilengkapi dengan cara pengukuran optik untuk mendapatkan data-data eksperimen benar dan ini seterusnya meningkatkan maklumat-maklumat yang boleh diperolehi setiap eksperimen. Untuk merekabentuk sistem mikrobioreaktor, adalah perlu untuk menilai rekabentuk bagi keseluruhan sistem dan bukan menghadkan rekabentuk hanya pada cirri-ciri mekanikal reaktor sahaja. Dalam kertas kerja ini, dibincangkan penilaian rekabentuk yang penting dan ciri-ciri teknikal bagi penghasilan mikrobioreaktor untuk proses fermentasi aerobik. Ini termasuk saiz dan cara operasi reaktor, ciri-ciri mekanik reaktor (bahan-bahan, fabrikasi dan pengadukan), ciri-ciri bendalir reaktor (penyambungan, pengudaraan, pemeruapan dan strategi suapan), proses kawalan parameter fizikal (suhu, pH, dan oksigen terlarut) dan cara-cara untuk pengukuran kepekatan sel.

scholarly journals Perceived Facilitators and Barriers to Engaging with a Digital Intervention among Those with Food Insecurity, Binge Eating, and Obesity

Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2458
Author(s):  
Anu Venkatesh ◽  
Angela Chang ◽  
Emilie A. Green ◽  
Tianna Randall ◽  
Raquel Gallagher ◽  
...  
Keyword(s):  
Binge Eating ◽  
Food Insecurity ◽  
Future Research ◽  
Grocery Stores ◽  
User Centered Design ◽  
Design Considerations ◽  
Digital Intervention ◽  
Intervention Cost ◽  
Facilitators And Barriers ◽  
Important Design

Interventions that address binge eating and food insecurity are needed. Engaging people with lived experience to understand their needs and preferences could yield important design considerations for such interventions. In this study, people with food insecurity, recurrent binge eating, and obesity completed an interview-based needs assessment to learn facilitators and barriers that they perceive would impact their engagement with a digital intervention for managing binge eating and weight. Twenty adults completed semi-structured interviews. Responses were analyzed using thematic analysis. Three themes emerged. Participants shared considerations that impact their ability to access the intervention (e.g., cost of intervention, cost of technology, accessibility across devices), ability to complete intervention recommendations (e.g., affordable healthy meals, education to help stretch groceries, food vouchers, rides to grocery stores, personalized to budget), and preferred intervention features for education, self-monitoring, personalization, support, and motivation/rewards. Engaging people with lived experiences via user-centered design methods revealed important design considerations for a digital intervention to meet this population’s needs. Future research is needed to test whether a digital intervention that incorporates these recommendations is engaging and effective for people with binge eating and food insecurity. Findings may have relevance to designing digital interventions for other health problems as well.

scholarly journals Optical-Based Biosensors and Their Portable Healthcare Devices for Detecting and Monitoring Biomarkers in Body Fluids

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1285
Author(s):  
Anh Tran Tam Pham ◽  
Angus Wallace ◽  
Xinyi Zhang ◽  
Damian Tohl ◽  
Hao Fu ◽  
...  
Keyword(s):  
Medical Devices ◽  
Point Of Care ◽  
Body Fluids ◽  
Optical Measurements ◽  
Mobile Technologies ◽  
Detection Methods ◽  
Portable Devices ◽  
Bodily Fluids ◽  
Clinical Measurements ◽  
Distinct Features

The detection and monitoring of biomarkers in body fluids has been used to improve human healthcare activities for decades. In recent years, researchers have focused their attention on applying the point-of-care (POC) strategies into biomarker detection. The evolution of mobile technologies has allowed researchers to develop numerous portable medical devices that aim to deliver comparable results to clinical measurements. Among these, optical-based detection methods have been considered as one of the common and efficient ways to detect and monitor the presence of biomarkers in bodily fluids, and emerging aggregation-induced emission luminogens (AIEgens) with their distinct features are merging with portable medical devices. In this review, the detection methodologies that use optical measurements in the POC systems for the detection and monitoring of biomarkers in bodily fluids are compared, including colorimetry, fluorescence and chemiluminescence measurements. The current portable technologies, with or without the use of smartphones in device development, that are combined with optical biosensors for the detection and monitoring of biomarkers in body fluids, are also investigated. The review also discusses novel AIEgens used in the portable systems for the detection and monitoring of biomarkers in body fluid. Finally, the potential of future developments and the use of optical detection-based portable devices in healthcare activities are explored.

scholarly journals Fluid–Structure Coupling Effects in a Dual U-Tube Coriolis Mass Flow Meter

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 982
Author(s):  
Yuh-Chung Hu ◽  
Zen-Yu Chen ◽  
Pei-Zen Chang
Keyword(s):  
Product Design ◽  
Dynamic Balance ◽  
Fluid Viscosity ◽  
Fluid Structure ◽  
Development Platform ◽  
Design Considerations ◽  
Manufacture Process ◽  
Coupling Dynamics ◽  
Comsol Simulation ◽  
Important Design

Coriolis mass flowmeters are highly customized products involving high-degree fluid-structure coupling dynamics and high-precision manufacture. The typical delay from from order to shipment is at least 4 months. This paper presents some important design considerations through simulation and experiments, so as to provide manufacturers with a more time-efficient product design and manufacture process. This paper aims at simulating the fluid-structure coupling dynamics of a dual U-tube Coriolis mass flowmeter through the COMSOL simulation package. The simulation results are experimentally validated using a dual U-tube CMF manufactured by Yokogawa Co., Ltd. in a TAF certified flow testing factory provided by FineTek Co., Ltd. Some important design considerations are drawn from simulation and experiment. The zero drift will occur when the dual U-tube structure is unbalanced and therefore the dynamic balance is very important in the manufacturing of dual U-tube CMF. The fluid viscosity can be determined from the driving current of the voice coil actuator or the pressure loss between the inlet and outlet of CMF. Finally, the authors develop a simulation application based on COMSOL’s development platform. Users can quickly evaluate their design through by using this application. The present application can significantly shorten product design and manufacturing time.

scholarly journals Optical tools for ocean monitoring and research

Ocean Science ◽  
2009 ◽  
Vol 5 (4) ◽  
pp. 661-684 ◽  
Author(s):  
C. Moore ◽  
A. Barnard ◽  
P. Fietzek ◽  
M. R. Lewis ◽  
H. M. Sosik ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Ocean Color ◽  
Analytical Techniques ◽  
Optical Measurements ◽  
Physical Parameters ◽  
Optical Tools ◽  
Wide Range ◽  
Radiance Distribution ◽  
Ocean Monitoring ◽  
Methane Carbon

Abstract. Requirements for understanding the relationships between ocean color and suspended and dissolved materials within the water column, and a rapidly emerging photonics and materials technology base for performing optical based analytical techniques have generated a diverse offering of commercial sensors and research prototypes that perform optical measurements in water. Through inversion, these tools are now being used to determine a diverse set of related biogeochemical and physical parameters. Techniques engaged include measurement of the solar radiance distribution, absorption, scattering, stimulated fluorescence, flow cytometry, and various spectroscopy methods. Selective membranes and other techniques for material isolation further enhance specificity, leading to sensors for measurement of dissolved oxygen, methane, carbon dioxide, common nutrients and a variety of other parameters. Scientists are using these measurements to infer information related to an increasing set of parameters and wide range of applications over relevant scales in space and time.

An Approximate Analysis of Foundation Stresses in Horizontal Pressure Vessels

1980 ◽  
Vol 102 (3) ◽  
pp. 555-557
Author(s):  
Krishna P. Singh ◽  
V. K. Luk
Keyword(s):  
Solution Procedure ◽  
Pressure Vessels ◽  
Approximate Analysis ◽  
Loading Conditions ◽  
Mechanical Loads ◽  
Design Considerations ◽  
Desirable Feature ◽  
Horizontal Pressure ◽  
Linear Manner ◽  
Important Design

Saddle supports of horizontally mounted pressure vessels, when subject to seismic and mechanical loads, interact with the foundation in a highly non-linear manner. The maximum foundation concrete pressure, and hold-down bolt stresses are important design considerations which often govern the vessel support geometry. A method is given herein to determine the foundation stresses due to arbitrary imposed loadings. The solution procedure lends itself easily to automated computation—a highly desirable feature—since most nuclear equipment has to be analyzed for a large number of loading conditions.

Climate Geoengineering and the Role of Public Deliberation: A Comment on the us National Academy of Sciences’ Recommendations on Public Participation

Climate Law ◽  
2015 ◽  
Vol 5 (2-4) ◽  
pp. 252-294 ◽  
Author(s):  
William C. G. Burns ◽  
Jane A. Flegal
Keyword(s):  
Public Participation ◽  
Public Deliberation ◽  
National Academy Of Sciences ◽  
World Community ◽  
Design Considerations ◽  
The Us ◽  
The World ◽  
Academy Of Sciences ◽  
Important Design

The feckless response of the world community to the mounting threat of climate change has led to a growing interest in climate geoengineering research. In early 2015, the us National Academy of Sciences released two major reports on the topic. While it is notable that both reports recommended some form of public participation to inform research, this article argues that the vagueness of these recommendations could mean that their implementation might not comport with optimal approaches for public deliberation. We outline some options for public deliberation on climate geoengineering and important design considerations.

An Improved 2DCNN With Focal Loss Function for Blade Icing Detection of Wind Turbines Under Imbalanced SCADA Data

2021 ◽  
Author(s):  
Dandan Peng ◽  
Chenyu Liu ◽  
Wim Desmet ◽  
Konstantinos Gryllias
Keyword(s):  
Power Generation ◽  
Deep Learning ◽  
Wind Turbine ◽  
Loss Function ◽  
Wind Turbines ◽  
Cold Climate ◽  
Detection Methods ◽  
Physical Parameters ◽  
Learning Abilities ◽  
Imbalance Problem

Abstract The deployment of wind power plants in cold climate becomes ever more attractive due to the increased air density resulting from low temperatures, the high wind speeds, and the low population density. However, the cold climate conditions bring some additional challenges as itt can easily cause wind turbine blades to freeze. The frizzing ice on blades not only increases the energy required for the rotation of blades, resulting in a reduction in the power generation, but also increases the amplitude of the blades’ vibrations, which may cause the blade to break, affecting the power generation performance of the wind turbine and poses a threat to its safe operation. Current published blade icing detection methods focus on studying the blade icing mechanism, building the model and then judging if it is iced or not. These models vary with different wind turbines and working conditions, so expertise knowledge is required. However, deep learning techniques may solve the abovementioned problem based on their excellent feature learning abilities but until now, there are only few studies on wind turbine blade icing detection based on the deep learning technology. Therefore, this paper proposes a novel blade icing detection model, named two-dimensional convolutional neural network with focal loss function (FL-2DCNN). The network takes the raw data collected by the Supervisory Control and Data Acquisition (SCADA) system as input, automatically learns the correlation between the different physical parameters in the dataset, and captures the abnormal information, in order to accurately output the detection results. However, the amount of normal data collected by SCADA systems is usually much larger than the one of blade icing fault data, leading to a serious data imbalance problem. This problem makes it difficult for the network to obtain enough features related to the blade icing fault. Therefore the focal loss function is introduced to the FL-2DCNN to solve the aforementioned data imbalanced problem. The focal loss function can effectively balance the importance of normal samples and icing fault samples, so that the network can obtain more icing-related feature information from the icing fault samples, and thus the detection ability of the network can be improved. The experimental results of the proposed FL-2DCNN based on real SCADA data of wind turbines show that the proposed FL-2DCNN can effectively solve the sample imbalance problem and has significant potential in the blade icing detection task compared with other deep learning methods.

An Exact Solution for Flow Transients in Two-Phase Systems by the Method of Characteristics

1973 ◽  
Vol 95 (4) ◽  
pp. 470-476 ◽  
Author(s):  
J. M. Gonzalez-Santalo ◽  
R. T. Lahey
Keyword(s):  
Exact Solution ◽  
Method Of Characteristics ◽  
Accurate Analysis ◽  
Two Phase ◽  
Design Considerations ◽  
The Method Of Characteristics ◽  
System Flow ◽  
Hypothetical Accident ◽  
Phase Systems ◽  
Important Design

One of the important design considerations in modern water-cooled nuclear reactors is their thermal performance during hypothetical accident situations. However, an accurate analysis of the system thermal-hydraulics is required before the thermal margins can be appraised. In this paper, an analysis based on the method of characteristics has been developed by which the exact solution to flow decay transients in homogeneous two-phase systems can be obtained. The exact solution presented yields the system flow and quality at each point in space and time during an exponential flow decay transient. These parameters can then be combined with an appropriate CHF correlation to predict the occurrence of transient CHF.

scholarly journals Design Tradeoffs in the Development of a Wearable Soft Exoskeleton for Upper Limb Mobility Disorders

2019 ◽  
Author(s):  
Esther Foo ◽  
Heidi Woelfle ◽  
Brad Holschuh
Keyword(s):  
Shape Memory Alloy ◽  
Power Input ◽  
The Body ◽  
Crucial Point ◽  
Mobility Support ◽  
Design Considerations ◽  
Design Variables ◽  
Design Tradeoffs ◽  
Sma Spring ◽  
Important Design

This paper investigates the tradeoffs between design variables important for the development of a mobility support soft exoskeleton for horizontal shoulder adduction. The soft exoskeleton utilizes discreet shape memory alloy (SMA) spring actuators to generate the required torque to move the arm segment, while preserving the qualities of a soft, wearable garment solution. A pilot benchtop test involving varying power input, actuator anchor position, actuator orientation, and added weight, was investigated to evaluate their effects against the degree of motion the soft exoskeleton allows. The results show that the power input, actuator anchor position, and simulated limb weight each affect the ultimate horizontal adduction angle the exoskeleton is able to induce. Further, the project highlights a crucial point in regard to the tradeoffs between functionality and wearability: when actuator orientation was investigated, we found a decrement in functionality (as measured by maximum achievable horizontal adduction angle) when the actuators were constrained close to the body. This shows that when aiming to improve the hypothetical system’s wearability/usability, the effective torque that can be generated is reduced. Together these findings demonstrate important design considerations while developing a wearable, soft exoskeleton system that is capable of effectively supporting movement of the body while maintaining the comfort and discreetness of a regular garment.

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