Cost effective transparent long-distance interconnection of metropolitan networks over ultra-long-haul optical links

2004 ◽  
Author(s):  
A. Ehrhardt ◽  
N. Hanik
Keyword(s):  
Cost Effective ◽  
Long Distance ◽  
Optical Links ◽  
Metropolitan Networks

scholarly journals PSVII-3 Correlations between L-lactate concentrations obtained using a handheld lactate analyser and a lactate assay colorimetric kit in beef cattle transported by road

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 296-297
Author(s):  
Daniela M Meléndez ◽  
Sonia Marti ◽  
Luigi Faucitano ◽  
Derek B Haley ◽  
Timothy D Schwinghamer ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Cost Effective ◽  
Road Transportation ◽  
Long Distance ◽  
Suitable Alternative ◽  
Blood Samples ◽  
Handheld Device ◽  
Time Points ◽  
Relationship Of ◽  
The Relationship

Abstract Blood metabolites are used to assess a variety of animal conditions for veterinary diagnosis and research. Concentration of metabolites in blood can be measured using a commercially-available lab-based assay or in real-time using a handheld device developed to be more time- and cost-effective than the lab-based method. Lactate is a product of anaerobic glycolysis, used in animal research as an indicator of muscle fatigue. Therefore, it has been used as an indicator of cattle response to long distance transportation. The aim of this study was to assess the relationship of L-lactate concentrations measured using a Lactate Scout+ analyzer (Lactate Scout, EFK Diagnostics, Barleben, Germany) and a lactate assay colorimetric kit (Lactate Assay Kit, Cell Biolabs Inc., San Diego, CA). Blood samples were collected by venipuncture from 96 steers (245 ± 35.7 kg BW) prior to (L1) and after 36 h, and prior to and after an additional 4 h of road transportation, and on d 1, 2, 3, 5, 14, and 28 after transport. The Lactate Scout+ analyzer strip was dipped in blood at the time of sampling, while blood samples were collected into sodium fluoride tubes for use in colorimetric analysis. Pearson correlations were calculated to determine the relationship between the experimental methods for the quantification of L-lactate concentrations. The strengths and levels of statistical significance of the correlation varied over the observed time points, r = -0.03, P = 0.75 (L1) to r = 0.75, P = < 0.0001 (d 3). The correlation for the pooled data was weak but statistically significant (r = 0.33, P < 0.001). Based on the experimental results, the Lactate Scout+ analyzer is not a suitable alternative to a lab-based assay for measuring L-lactate in transported cattle, due to variability across sampling time points and weak correlation with the traditional enzymatic method.

scholarly journals Sheep scab spatial distribution: the roles of transmission pathways

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Emily Joanne Nixon ◽  
Ellen Brooks-Pollock ◽  
Richard Wall
Keyword(s):  
Disease Transmission ◽  
Movement Control ◽  
Cost Effective ◽  
Infected Sheep ◽  
Disease Spread ◽  
Psoroptes Ovis ◽  
Long Distance ◽  
Sheep Scab ◽  
The Uk ◽  
The Impact

Abstract Background Ovine psoroptic mange (sheep scab) is a highly pathogenic contagious infection caused by the mite Psoroptes ovis. Following 21 years in which scab was eradicated in the UK, it was inadvertently reintroduced in 1972 and, despite the implementation of a range of control methods, its prevalence increased steadily thereafter. Recent reports of resistance to macrocyclic lactone treatments may further exacerbate control problems. A better understanding of the factors that facilitate its transmission are required to allow improved management of this disease. Transmission of infection occurs within and between contiguous sheep farms via infected sheep-to-sheep or sheep–environment contact and through long-distance movements of infected sheep, such as through markets. Methods A stochastic metapopulation model was used to investigate the impact of different transmission routes on the spatial pattern of outbreaks. A range of model scenarios were considered following the initial infection of a cluster of highly connected contiguous farms. Results Scab spreads between clusters of neighbouring contiguous farms after introduction but when long-distance movements are excluded, infection then self-limits spatially at boundaries where farm connectivity is low. Inclusion of long-distance movements is required to generate the national patterns of disease spread observed. Conclusions Preventing the movement of scab infested sheep through sales and markets is essential for any national management programme. If effective movement control can be implemented, regional control in geographic areas where farm densities are high would allow more focussed cost-effective scab management. Graphical Abstract

scholarly journals Drift Reduction of a 4-DOF Measurement System Caused by Unstable Air Refractive Index

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6329
Author(s):  
Ruijun Li ◽  
Yongjun Wang ◽  
Pan Tao ◽  
Rongjun Cheng ◽  
Zhenying Cheng ◽  
...  
Keyword(s):  
Refractive Index ◽  
Laser Beam ◽  
Measurement System ◽  
Degrees Of Freedom ◽  
Cost Effective ◽  
Control Mode ◽  
Detection Accuracy ◽  
Long Distance ◽  
Cost Effective Method ◽  
Novel Method

Laser beam drift greatly influences the accuracy of a four degrees of freedom (4-DOF) measurement system during the detection of machine tool errors, especially for long-distance measurement. A novel method was proposed using bellows to serve as a laser beam shield and air pumps to stabilize the refractive index of air. The inner diameter of the bellows and the control mode of the pumps were optimized through theoretical analysis and simulation. An experimental setup was established to verify the feasibility of the method under the temperature interference condition. The results indicated that the position stability of the laser beam spot can be improved by more than 79% under the action of pumping and inflating. The proposed scheme provides a cost-effective method to reduce the laser beam drift, which can be applied to improve the detection accuracy of a 4-DOF measurement system.

scholarly journals Cost-Effective Edge Server Placement in Wireless Metropolitan Area Networks

Sensors ◽  
2018 ◽  
Vol 19 (1) ◽  
pp. 32 ◽  
Author(s):  
Feng Zeng ◽  
Yongzheng Ren ◽  
Xiaoheng Deng ◽  
Wenjia Li
Keyword(s):  
Metropolitan Area ◽  
Dominating Set ◽  
Cost Effective ◽  
Mobile Users ◽  
Metropolitan Area Networks ◽  
New Paradigm ◽  
Long Distance ◽  
On Demand ◽  
Wireless Metropolitan Area Networks ◽  
Definition Of

Remote clouds are gradually unable to achieve ultra-low latency to meet the requirements of mobile users because of the intolerable long distance between remote clouds and mobile users and the network congestion caused by the tremendous number of users. Mobile edge computing, a new paradigm, has been proposed to mitigate aforementioned effects. Existing studies mostly assume the edge servers have been deployed properly and they just pay attention to how to minimize the delay between edge servers and mobile users. In this paper, considering the practical environment, we investigate how to deploy edge servers effectively and economically in wireless metropolitan area networks. Thus, we address the problem of minimizing the number of edge servers while ensuring some QoS requirements. Aiming at more consistence with a generalized condition, we extend the definition of the dominating set, and transform the addressed problem into the minimum dominating set problem in graph theory. In addition, two conditions are considered for the capacities of edge servers: one is that the capacities of edge servers can be configured on demand, and the other is that all the edge servers have the same capacities. For the on-demand condition, a greedy based algorithm is proposed to find the solution, and the key idea is to iteratively choose nodes that can connect as many other nodes as possible under the delay, degree and cluster size constraints. Furthermore, a simulated annealing based approach is given for global optimization. For the second condition, a greedy based algorithm is also proposed to satisfy the capacity constraint of edge servers and minimize the number of edge servers simultaneously. The simulation results show that the proposed algorithms are feasible.

scholarly journals Integrated Dual-DFB PIC for High-Purity THz Carrier Generation Enabling Ultrafast THz Wireless Communications

2021 ◽  
Author(s):  
Shi Jia ◽  
Mu-Chieh Lo ◽  
Lu Zhang ◽  
Oskars Ozolins ◽  
Aleksejs Udalcovs ◽  
...  
Keyword(s):  
Wireless Communications ◽  
Integrated Circuits ◽  
High Purity ◽  
High Speed ◽  
Single Channel ◽  
Cost Effective ◽  
Long Distance ◽  
Practical Applications ◽  
Integrated Cost ◽  
Thz Power

Abstract With the explosive growth of global wireless data traffic, the Terahertz band (0.3–10 THz) is promising for ultrafast wireless communications, due to the enormous available bandwidth [1]. Photonic generation of THz carriers displays extremely large tunable range and modulation bandwidth, making it nearly ideal for THz communications. However, the current photonics-based THz carrier generators are based on discrete bulky components [2] with high cost and energy consumption, which hinder them from practical applications. Here, we present an injection-locked heterodyne source based on generic foundry-fabricated photonic integrated circuits (PIC) attached to a photo-mixing uni-travelling carrier photodiode (UTC-PD), generating high-purity THz carriers for high-speed and long-distance wireless communication. The generated THz carrier can span from 0 to 1.4 THz, determined by the tunable wavelength spacing between the two distributed feedback (DFB) modes within the range 0-10.7 nm. We show that a generated 0.4 THz carrier transmits a record-high single-channel net rate of 131 Gbit/s over 10.7 m of wireless distance with only − 24 dBm emitted THz power, by employing 16-QAM-OFDM modulation and a nonlinear equalization technique. To the best of our knowledge, this is the highest data rate for a single-channel THz wireless transmission and requires the lowest THz power/bitrate/distance. The scheme of the monolithic dual-DFB PIC based THz generation shows a great potential for fully integrated, cost-effective and energy-efficient THz transmitters.

scholarly journals A Cost-Effective Approach to the Risk Reduction of Cable Fault Triggered by Laying Repeaters of Fiber-Optic Submarine Cable Systems in Deep-Sea

2021 ◽  
Vol 9 (9) ◽  
pp. 939
Author(s):  
Yukitoshi Ogasawara ◽  
Wataru Natsu
Keyword(s):  
Deep Sea ◽  
Mechanical Stability ◽  
Optical Amplifiers ◽  
Cost Effective ◽  
Optical Signal ◽  
Submarine Cable ◽  
Long Distance ◽  
Cost Effective Approach ◽  
Cable Systems ◽  
Cable Damage

Long-distance submarine cable systems, such as the transoceanic system, generally consist of a series of cables and repeaters. Repeater units are spaced at regular intervals to boost the attenuated optical signal and presently contain optical amplifiers in a pressure vessel made of copper alloy. Since the repeater unit is more massive than the cable, it pulls the cable catenary locally toward the seabed. In the 1990s, several studies numerically simulated cable behavior in the water and showed that the seabed slack runs short, and the seabed cable tension increases just before the repeater reaches the seabed. Therefore, it has been pointed out that an unarmored cable with a polyethylene sheath can be easily damaged. However, no reports have been published regarding the actual situation of cable faults related to the laying of repeaters. This study quantitatively analyzes the mechanism of cable damage related to the laying of repeaters, based on experiments, simulations, maintenance records, and a comparative analysis between the simulation results and actual cable faults. Cost-effective methods to mitigate cable faults triggered by laying a repeater in the deep sea are also explored to ensure mechanical stability during the design lifetime.

scholarly journals Children Virtual Concert in the Covid-19 Pandemic

2020 ◽  
Vol 3 (2) ◽  
pp. 247-260
Author(s):  
Putu Sandra Devindriati Kusuma
Keyword(s):  
Social Media ◽  
Research Methods ◽  
Positive Impact ◽  
Cost Effective ◽  
Long Distance ◽  
New Normal ◽  
Children And Parents ◽  
The World ◽  
At Home ◽  
Descriptive Qualitative

Purpose: This article aims to see a children virtual concert held by La Prima Course and Bandung Philharmonic. Both of them held an online concert in June 2020, when the world was entering new normal era due to Covid-19 pandemic. Research methods: The method used in writing this article is descriptive-qualitative by observing watching two virtual concert and long-distance interviews through social media. Results and discussion: Children virtual concert have a positive impact for children as activities at home during the Covid-19 pandemic. Other impacts were also felt by the organizers so that the organizers were enthusiastic to routinely hold virtual performances. Implication: Covid-19 pandemic makes virtual performance a cost-effective and attractive choice for organizers, children, and parents who concern about art.

scholarly journals Towards long-distance quantum networks with superconducting processors and optical links

2019 ◽  
Vol 4 (4) ◽  
pp. 045003 ◽  
Author(s):  
Sourabh Kumar ◽  
Nikolai Lauk ◽  
Christoph Simon
Keyword(s):  
Long Distance ◽  
Quantum Networks ◽  
Optical Links

Ways to get water: rainwater utilization or long-distance water supply? A holistic assessment

1997 ◽  
Vol 36 (8-9) ◽  
pp. 313-318 ◽  
Author(s):  
Thilo Herrmann ◽  
Karin Hasse
Keyword(s):  
Water Supply ◽  
Market Price ◽  
Cost Effective ◽  
Supply System ◽  
Long Distance ◽  
Retention Capacity ◽  
Drinking Water Supply System ◽  
Holistic Assessment ◽  
Stormwater Retention

On the basis of a case study the costs of an existing long-distance drinking water supply system are compared to the potentiel costs of decentralized rainwater collection und usage systems. The costs of stormwater retention are included in the calculations in so far as rainwater utilization systems provide a retention capacity for stormwater in the cisterns. The results show, that in dependence of the market price of the rainwater usage systems, the decentral way to provide usage water to the households can be more cost effective compared to a central long-distance supply system.

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