scholarly journals Low-Cost WSN Monitoring and Location of Small Ruminants Using Transmission-Loss Inversion on Open Grassland in Brazil

2012 ◽  
Vol 2 (5) ◽  
pp. 101-110
Author(s):  
J. M. R. de Souza Neto ◽  
J. J. C. Silva ◽  
T. C. M. Cavalcanti ◽  
J. S. da Rocha Neto ◽  
I. A. Glover
2021 ◽  
Vol 185 ◽  
pp. 106172
Author(s):  
Rui Guedes ◽  
Paulo Pedreiras ◽  
Luís Nóbrega ◽  
Pedro Gonçalves

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4140
Author(s):  
Maoxiang Hou ◽  
Jun He ◽  
Xizhen Xu ◽  
Ziliang Li ◽  
Zhe Zhang ◽  
...  

We propose and demonstrate a cascaded hollow-core fiber (HCF) device for multi-parameter sensing based on the combination of antiresonant reflecting guidance (ARRG) and Mach-Zender interference (MZI). The device was fabricated by splicing two sections of HCF together. Two sets of fringes, which have different free spectral ranges, were generated from ARRG and MZI, respectively, and were aliasing in the transmission spectrum. The two sets of fringes were then separated using a band pass filter and a Gaussian fitting technique. The wavelengths at two transmission loss dips formed by ARRG and MZI exhibit a temperature sensitivity of 14.1 and 28.5 pm/°C, and a strain sensitivity of 0.4 and −0.8 pm/με, respectively. By using a crossing matrix with differences sensitivities, the cross-sensitivity between temperature and strain can be solved. The gas pressure response of the cascaded HCF device was also tested up to 300 °C, and linear relationships between the gas pressure sensitivities and temperature were found, which can be used in gas pressure application in various temperatures. Moreover, the proposed cascaded HCF sensor is compact, low cost, and simple for fabrication, and hence offers a promising way for the simultaneous measurement of multiple parameters, such as temperature, strain, and gas pressure.


2005 ◽  
Vol 17 (9) ◽  
pp. 68
Author(s):  
G. B. Martin

This paper considers strategies to improve the reproductive performance of small ruminants in ways that lead to production systems that are ‘clean, green and ethical’. This view arises from feedback from consumers, particularly in attractive export markets, and from a need to refocus on the needs of Australian producers, most of whom operate large, extensive enterprises. These people cannot use ‘high-tech’ systems but need low-cost, low-labour solutions to their problems. First, to control of the timing of reproductive events, they can use the socio-sexual inputs of the ‘male effect’ to induce synchronised ovulation in females that would otherwise be anovulatory (seasonal, lactational, prepubertal). Second, they can use nutritional stimuli for ‘focus feeding’, in which short periods of nutritional supplements are precisely timed and specifically designed for individual events in the reproductive process: gamete production, embryo survival, ‘fetal programming’ and colostrum production. Third, they can use simple behavioural observations to genetically select for temperament – this will maximize offspring survival, product quality and animal welfare. All of these approaches involve non-pharmacological manipulation of the endogenous control systems of the animals and complement the detailed information from ultrasound that is now becoming available.1 The use of such clean, green and ethical tools in the management of our animals can be cost-effective, increase productivity and, at the same time, greatly improve the image of meat and milk industries in society and the marketplace. This does not mean, however, that they will not benefit from the opportunities that evolve from breakthroughs in reproductive technology or gene research. On the contrary, if this ‘high-tech’ research is done within the context of the needs of a ‘clean, green and ethical’ industry, first class science can have very direct and immediate benefits to our livestock industries. (1)Martin GB, Milton JTB, Davidson RH, Banchero Hunzicker GE, Lindsay DR and Blache D. (2004). Natural methods of increasing reproductive efficiency in sheep and goats. Anim. Reprod. Sci. 82–83, 231–246.


2018 ◽  
Vol 2018 (1) ◽  
pp. 000415-000418 ◽  
Author(s):  
Shinichiro Abe ◽  
Kazuyuki Mitsukura ◽  
Yuki Imazu ◽  
Masaya Toba ◽  
Takashi Masuko ◽  
...  

Abstract The interposer or fan-out packaging technology with ultra-fine line/space and high frequency signal has been required in order to achieve high speed interconnection between chips with low cost. In this paper, we have newly developed low Dk and Df photosensitive insulation material. The additional features of the developed materials are very low moisture absorptivity less than 0.3 wt%, low anion impurities and high resistance to hydrolysis. The micro-strip line was fabricated to evaluate the influence of developed material. The insertion loss from transmission lines on Material C shows much lower loss than the conventional reference material at higher frequencies. The peel strength to the sputtered Ti and Cu is over 0.7 kN/m. The material also demonstrated SAP fabrication compatibility with fine circuitry and passed insulation reliability by biased-HAST showing no copper migration measured by EDX.


2013 ◽  
Vol 50 (3) ◽  
pp. 426-437 ◽  
Author(s):  
E. TSIPLAKOU ◽  
G. ECONOMOU ◽  
I. HADJIGEORGIOU ◽  
A. KOMINAKIS ◽  
G. ZERVAS

SUMMARYThe establishment of leys for biomass production during the winter months could be an alternative feed resource of low cost for small ruminants in Mediterranean basin. For this purpose, an experiment was carried out with six plant species mixtures (PSM) that were cut up to seven times from seeding. The results showed that all the PSM had their highest growth at the 2nd cut withFestuca arundinacea,Lolium perenne,Dactylis glomerata,Trifolium repens(FLDT) being superior as the dry matter production concerns compared with the PSM that gave seven cuts. The crude protein and the ether extracts contents in all the PSM decreased from the 1st to the last cut, while that of NDF and ADF increased. The concentrations of myristic, palmitic, stearic, oleic and linoleic acid increased in all the PSMs from the 2nd to the 5th cut, while the opposite was observed for the α-linolenic acid content. The concentration of α-linolenic acid was higher in the FLDT PSM when compared to others during all cuts. Taking into account all the examined parameters together, the FLDT seems to be superior to the other PSMs as animal feed for small ruminants, particularly during the period where there is no available grass from natural grasslands.


Materials ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 373
Author(s):  
Haoqiang Gao ◽  
Qun Yan ◽  
Xusheng Liu ◽  
Ying Zhang ◽  
Yongtao Sun ◽  
...  

In order to achieve the dual needs of single-phase vibration reduction and lightweight, a square honeycomb acoustic metamaterials with local resonant Archimedean spirals (SHAMLRAS) is proposed. The independent geometry parameters of SHAMLRAS structures are acquired by changing the spiral control equation. The mechanism of low-frequency bandgap generation and the directional attenuation mechanism of in-plane elastic waves are both explored through mode shapes, dispersion surfaces, and group velocities. Meanwhile, the effect of the spiral arrangement and the adjustment of the equation parameters on the width and position of the low-frequency bandgap are discussed separately. In addition, a rational period design of the SHAMLRAS plate structure is used to analyze the filtering performance with transmission loss experiments and numerical simulations. The results show that the design of acoustic metamaterials with multiple Archimedean spirals has good local resonance properties, and forms multiple low-frequency bandgaps below 500 Hz by reasonable parameter control. The spectrograms calculated from the excitation and response data of acceleration sensors are found to be in good agreement with the band structure. The work provides effective design ideas and a low-cost solution for low-frequency noise and vibration control in the aeronautic and astronautic industries.


2021 ◽  
Author(s):  
Shahad I Younus ◽  
Anwaar A Al-Dergazly ◽  
A K Abass

Abstract Optical filters based on cascade single mode - multimode - single mode fiber structure (SMS) has considerable attention as a reliable optical device the reliability is due to its simplicity, compactness, low cost, all fiber device, low transmission loss, and can be continuously tune the laser wavelength at a specific spectral range. The principle of the operation is based on self- image and multimode interference (MMI) phenomena. A tunable filter was simulated based on cascade single mode-no core-single mode (SNS) fiber structure surrounded by magneto-optical fluid (MOF) using finite element method (FEM), the influence of the no core fiber (NCF) diameter and length on the tunablility and the bandwidth is investigated and optimized. Two materials were adopted as a MOF. The results show that the tunability of the filter can be improved by decreasing the NCF diameter. A continuous wavelength tunability about 37 nm from 1518 to 1555 nm with a bandwidth about 10 nm is obtained. The device is highly stable, inexpensive, provide wide tuning range compared with other tuning methods. This device can be used in optical communication, fiber sensor, spectroscopy, and in fiber laser technology. To the best of our knowledge, this is the first optical fiber MMI tunable filter by magnetic field effect.


2021 ◽  
Vol 11 (12) ◽  
pp. 5372
Author(s):  
Manuela Neri ◽  
Elisa Levi ◽  
Eva Cuerva ◽  
Francesc Pardo-Bosch ◽  
Alfredo Guardo Zabaleta ◽  
...  

From a construction point of view, neighborhoods with residents living at or below the poverty threshold are characterized by low energy efficiency buildings, in which people live in acoustic discomfort with no viable options for home improvements, as they usually can not afford the materials and labor costs associated. An alternative to this is to use low-cost insulating elements made of non-conventional materials with acceptable acoustic properties. Given that household materials at their end-of-life (EoLHM) are free of costs and available also to the more disadvantaged population, they can be used to build acoustic panels for such contexts. This approach embraces several benefits since it reduces the amount of waste produced, the footprint deriving from the extraction of new raw materials and, by highlighting the potential of the EoLHM, discourages the abandonment of waste. In this paper, the acoustic properties of EoLHM, such as cardboard, egg-cartons, clothes, metal elements and combinations of them, are investigated by means of the impedance tube technique. The measured sound absorption coefficient and transmission loss have shown that EoLHM can be used for the realization of acoustic panels. However, since none of the analyzed materials shows absorbing and insulating properties at the same time, EoLHM must be wisely selected. This innovative approach supports the circular economy and the improvement for the living condition of low-income households.


2015 ◽  
Vol 153 (7) ◽  
pp. 1302-1309 ◽  
Author(s):  
C. FERNÁNDEZ ◽  
M. C. LÓPEZ ◽  
M. LACHICA

SUMMARYImprovements of a home-made mobile open-circuit respirometry system for the rapid determination of methane (CH4) and carbon dioxide (CO2) production, oxygen (O2) consumption and, thereafter, heat production (HP) for small ruminants are described and validated. Upgrades consisted of three main features: utilization of a head hood (replacing the previous face mask); use of a computerized control system, data acquisition and recording for gases and air flux (replacing collecting bags for air sampling); and use of a gas cooler to remove the air sample moisture (replacing the chemical drier (silica gel) approach). Calibration factors were established by injecting nitrogen (N2) and CO2 in the system into the head hood. Repetitive and consistent values for the calibration factor were obtained for O2 and CO2 which confirmed the absence of leaks and the good performance of the system. In addition, an experimental test with 12 Manchega female dry sheep was conducted to validate the system. Three diets based on cereal grain, fibrous by-products and alfalfa hay (ALH) were used with four sheep per diet. Metabolizable energy intake was close to metabolizable energy for maintenance. Average HP measured by indirect calorimetry (respiratory quotient (RQ) method) was close to the average HP determined from Carbon–Nitrogen balance (CN method) accounting for 443 and 426 kJ/kg0·75 body weight (BW) per day, respectively. Fasting HP was determined by the RQ method with two sheep from the ALH diet accounting for 269 kJ/kg0·75 BW per day. The head hood and computerized control, data acquisition and recording as well as the gas cooler improved the system by reducing the labour input without loss of functionality for measuring gas exchange and energy metabolism in small ruminants.


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