Optimal UFLS Settings: An Assessment of Frequency System Response Indicators

Abstract This paper presents an overview of techniques utilizing natural phytoplankton for the detection of metal-Induced stress in the Great Lakes. Both field and laboratory procedures are designed to evaluate either structural changes or functional response of test organisms. This up-to-date compendium provides a choice of techniques, which permits a holistic assessment of the stress caused by toxic metals. Recently introduced techniques, such as normalized size spectra analysis, flow cytometry, and the evaluation of a continuous-flow system response to metal toxicity, are discussed in more detail to explore their future potential. Owing to their key position in the food web, high turnover rates, abundance, and sensitivity to environmental perturbation, phytoplankton serve as reliable early warning indicators of ecosystem deterioration and its restoration.

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Treatment system response to transient AOX (adsorbable organic halogen) loadings

Water Science & Technology ◽

10.2166/wst.1997.0489 ◽

1997 ◽

Vol 35 (2-3) ◽

pp. 85-91

Author(s):

D. A. Barton ◽

J. D. Woodruff ◽

T. M. Bousquet ◽

A. M. Parrish

Keyword(s):

Paper Industry ◽

Model Development ◽

Operating Conditions ◽

System Response ◽

Additional Information ◽

Organic Halogen ◽

Aox Removal ◽

Variable Operating Conditions ◽

Plant Shutdown

If promulgated as proposed, effluent guidelines for the U.S. pulp and paper industry will impose average monthly and maximum daily numerical limits of discharged AOX (adsorbable organic halogen). At this time, it is unclear whether the maximum-day variability factor used to establish the proposed effluent guidelines will provide sufficient margin for mills to achieve compliance during periods of normal but variable operating conditions within the pulping and bleaching processes. Consequently, additional information is needed to relate transient AOX loadings with final AOX discharges. This paper presents a simplistic dynamic model of AOX decay during treatment. The model consists of hydraulic characterization of an activated sludge process and a first-order decay coefficient for AOX removal. Data for model development were acquired by frequent collection of influent and effluent samples at a bleach kraft mill during a bleach plant shutdown and startup sequence.

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Assessing genomic diversity and signatures of selection in Jiaxian Red cattle using whole-genome sequencing data

BMC Genomics ◽

10.1186/s12864-020-07340-0 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Xiaoting Xia ◽

Shunjin Zhang ◽

Huaju Zhang ◽

Zijing Zhang ◽

Ningbo Chen ◽

...

Keyword(s):

Population Structure ◽

Whole Genome Sequencing ◽

Genome Sequencing ◽

Genomic Variation ◽

Genomic Diversity ◽

System Response ◽

Whole Genome ◽

Population Structure Analysis ◽

Native Cattle ◽

Genomic Regions

Abstract Background Native cattle breeds are an important source of genetic variation because they might carry alleles that enable them to adapt to local environment and tough feeding conditions. Jiaxian Red, a Chinese native cattle breed, is reported to have originated from crossbreeding between taurine and indicine cattle; their history as a draft and meat animal dates back at least 30 years. Using whole-genome sequencing (WGS) data of 30 animals from the core breeding farm, we investigated the genetic diversity, population structure and genomic regions under selection of Jiaxian Red cattle. Furthermore, we used 131 published genomes of world-wide cattle to characterize the genomic variation of Jiaxian Red cattle. Results The population structure analysis revealed that Jiaxian Red cattle harboured the ancestry with East Asian taurine (0.493), Chinese indicine (0.379), European taurine (0.095) and Indian indicine (0.033). Three methods (nucleotide diversity, linkage disequilibrium decay and runs of homozygosity) implied the relatively high genomic diversity in Jiaxian Red cattle. We used θπ, CLR, FST and XP-EHH methods to look for the candidate signatures of positive selection in Jiaxian Red cattle. A total number of 171 (θπ and CLR) and 17 (FST and XP-EHH) shared genes were identified using different detection strategies. Functional annotation analysis revealed that these genes are potentially responsible for growth and feed efficiency (CCSER1), meat quality traits (ROCK2, PPP1R12A, CYB5R4, EYA3, PHACTR1), fertility (RFX4, SRD5A2) and immune system response (SLAMF1, CD84 and SLAMF6). Conclusion We provide a comprehensive overview of sequence variations in Jiaxian Red cattle genomes. Selection signatures were detected in genomic regions that are possibly related to economically important traits in Jiaxian Red cattle. We observed a high level of genomic diversity and low inbreeding in Jiaxian Red cattle. These results provide a basis for further resource protection and breeding improvement of this breed.

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Vibration characteristics of triple-gear-rotor system in compressed air energy storage under variable torque load

Science Progress ◽

10.1177/0036850420987058 ◽

2021 ◽

Vol 104 (1) ◽

pp. 003685042098705

Author(s):

Xinran Wang ◽

Yangli Zhu ◽

Wen Li ◽

Dongxu Hu ◽

Xuehui Zhang ◽

...

Keyword(s):

Large Scale ◽

Three Dimensional ◽

Element Model ◽

Rotor System ◽

Dynamic Responses ◽

System Response ◽

Rotating Speed ◽

Torque Load ◽

Set Up ◽

Two Stages

This paper focuses on the effects of the off-design operation of CAES on the dynamic characteristics of the triple-gear-rotor system. A finite element model of the system is set up with unbalanced excitations, torque load excitations, and backlash which lead to variations of tooth contact status. An experiment is carried out to verify the accuracy of the mathematical model. The results show that when the system is subjected to large-scale torque load lifting at a high rotating speed, it has two stages of relatively strong periodicity when the torque load is light, and of chaotic when the torque load is heavy, with the transition between the two states being relatively quick and violent. The analysis of the three-dimensional acceleration spectrum and the meshing force shows that the variation in the meshing state and the fluctuation of the meshing force is the basic reasons for the variation in the system response with the torque load. In addition, the three rotors in the triple-gear-rotor system studied show a strong similarity in the meshing states and meshing force fluctuations, which result in the similarity in the dynamic responses of the three rotors.

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What Solar–Terrestrial Link Researchers Should Know about Interplanetary Drivers

Universe ◽

10.3390/universe7050138 ◽

2021 ◽

Vol 7 (5) ◽

pp. 138

Author(s):

Yuri I. Yermolaev ◽

Irina G. Lodkina ◽

Lidia A. Dremukhina ◽

Michael Y. Yermolaev ◽

Alexander A. Khokhlachev

Keyword(s):

Interplanetary Shock ◽

Magnetic Storms ◽

System Response ◽

Ionospheric Disturbances ◽

Atmosphere System ◽

Compression Region ◽

Different Types ◽

Methodological Approaches ◽

Composite Nature ◽

Incorrect Data

One of the most promising methods of research in solar–terrestrial physics is the comparison of the responses of the magnetosphere–ionosphere–atmosphere system to various types of interplanetary disturbances (so-called “interplanetary drivers”). Numerous studies have shown that different types of drivers result in different reactions of the system for identical variations in the interplanetary magnetic field. In particular, the sheaths—compression regions before fast interplanetary CMEs (ICMEs)—have higher efficiency in terms of the generation of magnetic storms than ICMEs. The growing popularity of this method of research is accompanied by the growth of incorrect methodological approaches in such studies. These errors can be divided into four main classes: (i) using incorrect data with the identification of driver types published in other studies; (ii) using incorrect methods to identify the types of drivers and, as a result, misclassify the causes of magnetospheric-ionospheric disturbances; (iii) ignoring a frequent case with a complex, composite, nature of the driver (the presence of a sequence of several simple drivers) and matching the system response with only one of the drivers; for example, a magnetic storm is often generated by a sheath in front of ICME, although the authors consider these events to be a so-called “CME-induced” storm, rather than a “sheath-induced” storm; (iv) ignoring the compression regions before the fast CME in the case when there is no interplanetary shock (IS) in front of the compression region (“sheath without IS” or the so-called “lost driver”), although this type of driver generates about 10% of moderate and large magnetic storms. Possible ways of solving this problem are discussed.

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Virtual Peer-to-Peer Learning to Enhance and Accelerate the Health System Response to COVID-19: The HHS ASPR Project ECHO COVID-19 Clinical Rounds Initiative

Annals of Emergency Medicine ◽

10.1016/j.annemergmed.2021.03.035 ◽

2021 ◽

Author(s):

Richard C. Hunt ◽

Bruce B. Struminger ◽

John T. Redd ◽

Jack Herrmann ◽

B. Tilman Jolly ◽

...

Keyword(s):

Health System ◽

Peer Learning ◽

Peer To Peer ◽

System Response ◽

Project Echo

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Quantifying Road-Network Robustness toward Flood-Resilient Transportation Systems

Sustainability ◽

10.3390/su13063172 ◽

2021 ◽

Vol 13 (6) ◽

pp. 3172

Author(s):

Suchat Tachaudomdach ◽

Auttawit Upayokin ◽

Nopadon Kronprasert ◽

Kriangkrai Arunotayanun

Keyword(s):

Road Network ◽

Critical Infrastructure ◽

Policy Issue ◽

Analytical Framework ◽

Transportation Systems ◽

Network Robustness ◽

System Response ◽

Chiang Mai ◽

Protection Measures ◽

Response And Recovery

Amidst sudden and unprecedented increases in the severity and frequency of climate-change-induced natural disasters, building critical infrastructure resilience has become a prominent policy issue globally for reducing disaster risks. Sustainable measures and procedures to strengthen preparedness, response, and recovery of infrastructures are urgently needed, but the standard for measuring such resilient elements has yet to be consensually developed. This study was undertaken with an aim to quantitatively measure transportation infrastructure robustness, a proactive dimension of resilience capacities and capabilities to withstand disasters; in this case, floods. A four-stage analytical framework was empirically implemented: 1) specifying the system and disturbance (i.e., road network and flood risks in Chiang Mai, Thailand), 2) illustrating the system response using the damaged area as a function of floodwater levels and protection measures, 3) determining recovery thresholds based on land use and system functionality, and 4) quantifying robustness through the application of edge- and node-betweenness centrality models. Various quantifiable indicators of transportation robustness can be revealed; not only flood-damaged areas commonly considered in flood-risk management and spatial planning, but also the numbers of affected traffic links, nodes, and cars are highly valuable for transportation planning in achieving sustainable flood-resilient transportation systems.

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Vibro-Acoustical Sensitivities of Stiffened Aircraft Structures Due to Attached Mass-Spring-Dampers with Uncertain Parameters

Aerospace ◽

10.3390/aerospace8070174 ◽

2021 ◽

Vol 8 (7) ◽

pp. 174

Author(s):

Johannes Seidel ◽

Stephan Lippert ◽

Otto von Estorff

Keyword(s):

System Response ◽

Fuzzy Arithmetic ◽

Parameter Uncertainties ◽

Excitation Spectra ◽

Radiated Noise ◽

Linking Elements ◽

Manufacturing Tolerances ◽

Suitable Framework ◽

Mass Spring ◽

The Impact

The slightest manufacturing tolerances and variances of material properties can indeed have a significant impact on structural modes. An unintentional shift of eigenfrequencies towards dominant excitation frequencies may lead to increased vibration amplitudes of the structure resulting in radiated noise, e.g., reducing passenger comfort inside an aircraft’s cabin. This paper focuses on so-called non-structural masses of an aircraft, also known as the secondary structure that are attached to the primary structure via clips, brackets, and shock mounts and constitute a significant part of the overall mass of an aircraft’s structure. Using the example of a simplified fuselage panel, the vibro-acoustical consequences of parameter uncertainties in linking elements are studied. Here, the fuzzy arithmetic provides a suitable framework to describe uncertainties, create combination matrices, and evaluate the simulation results regarding target quantities and the impact of each parameter on the overall system response. To assess the vibrations of the fuzzy structure and by taking into account the excitation spectra of engine noise, modal and frequency response analyses are conducted.

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