174 research outputs found
White sturgeon (Acipenser transmontanus) optimum feeding rates at week 6 and 10 after initiation of feeding
No full textWhite sturgeon (Acipenser transmontanus) optimum feeding rates at week 6 and 10 after initiation of feeding.
No full text"The effects of feeding rates on growth performance and body proximate composition of white sturgeon juveniles 6 and 10 weeks after initiation of feeding were assessed. Two 1-week-long trials with six different feeding rates, replicated four times, were carried out. The feeding rates were 3.0, 4.0, 5.0, 6.0, 7.0, and 8.0% body weight (bw)\/day (d) in the first trial and 0.8, 1.6, 2.4, 3.2, 4.0, and 4.8% bw\/d in the second trial. Sixty fishes with 2.27 ± 0.9 g (mean ± SD) initial body weight were used in the first trial, and 25 fishes with 15.78 ± 4.4 g initial body weight were used in the second trial. The juveniles were kept at 18–19°C in small circular tanks (66 cm in diameter and 27 cm in water height) containing 90 L water and 3 L\/min flow and were fed a commercial salmonid soft-moist feed using automatic feeders. Mortality was almost zero (only one fish died in the first trial, which was unrelated to feeding rates). Specific growth rate (SGR), feeding efficiency, and body composition were significantly (P < 0.05) affected by feeding rates. Broken-line analysis of SGR indicated that the optimum feeding rates of white sturgeon juveniles were 6.5 ± 0.4% and 3.8 ± 0.1% bw\/d for the fifth and the 10th week after initiation of feeding.
Effect of ration and body size on the energy budget of juvenile white sturgeon
No full textGrowth and energy budget were measured for three sizes(2.4, 11.1 and 22.5 g) of juvenile white sturgeon Acipenser transmontanus held at 18.5 degrees C and fed tubificid worms at different levels ranging from starvation to ad libitum. For each size-class, specific growth rate increased linearly with increasing ration, and conversion efficiency was highest at the maximum ration. Growth rate decreased with increasing fish size at the maximum ration, but increased with size al each restricted ration. Conversion efficiency increased with increasing ration for each size-class and was usually highest at the maximum ration. Faecal production accounted for 3.2-5.2% of food energy. The proportion of food energy lost in nitrogenous excretion decreased with increasing ration. With increases in ration, the allocation of metabolizable energy to metabolism decreased, while that to growth increased. Fish size had no significant effect on the allocation of metabolizable energy to metabolism or growth. Al the maximum ration, on average 64.9% of metabolizable energy was spent on metabolism, and 35.1% on growth. (C) 1996 The Fisheries Society of the British Isle
Effects of dietary methylmercury on growth performance and tissue burden in juvenile green (Acipenser medirostris) and white sturgeon (A. transmontanus)
No full text"Triplicate groups of juvenile green and white sturgeon (30 +\/- 2 g) were exposed to one of the four nominal concentrations of dietary methylmercury (MeHg, 0 (control), 25, 50, and 100 mg MeHg\/kg diet) for 8 weeks to determine and compare the effects on growth performance and mercury (Hg) tissue burden in the two sturgeon species. Mortality, growth performance as measured by percent body weight increase per day, hepatosomatic index, proximate composition of whole body, and Hg burden in the whole body, gill, heart, liver, kidney, and white muscle were determined to assess the adverse growth effects and bioaccumulation of dietary MeHg in sturgeon. Significantly higher mortality and lower growth rate (p0.05) on the whole body proximate compositions of either sturgeon species. In conclusion, green sturgeon was more susceptible to dietary MeHg toxicity than white sturgeon in our 8-week growth experiment based on the higher mortality and lower growth rate and body energy contents.
Critical review of mitigation solutions for SSO in modern transmission grids
No full textThe replacement of conventional generation by power electronics-based generation changes the dynamic characteristics of the power system. This results in, among other things, the increased susceptibility to subsynchronous oscillations (SSO). First, this paper discusses three recently emerging SSO phenomena, which arise due to the interactions between (1) a doubly-fed induction generator and a series compensated transmission system; (2) a voltage source converter (VSC) and a weak grid; and (3) nearby VSCs. A fundamental review of these phenomena resulted in the requirement for a reclassification of the existing SSO phenomena. This reclassification is proposed in this work and is based on interacting components identified using participation factor analysis for the distinct phenomena. Second, a critical review of the existing mitigation measures is performed for these phenomena, highlighting the advantages and disadvantages of the solutions. The influence of the wind speed, grid strength, number of wind turbines, and several converter controller parameters are also discussed. To assist equipment manufacturers, control design engineers, and system operators in selecting and designing effective mitigation measures, the existing solutions are categorized in control solutions, hardware solutions, and solutions based on system level coordination. Finally, perspectives on open issues conclude this paper. Intelligent Electrical Power Grid
Spectrum of confined and interface phonons in complicated cylindrical nanoheterosystem placed into the plane quantum well in water
No full textThe energy spectra of all types of free vibrations existing in combined nanoheterosystem consisting of cylindrical
semiconductor quantum dot, semiconductor quantum ring embedded into the quantum well placed in water are studied in
the framework of dielectric continuum model. It is shown that depending on the boundary conditions for the potentials of
polarization fields there are two types of interface phonon modes: top (bottom) surface optical (TSO) modes and side
surface optical (SSO) modes
Gaia Data Release 3: Reflectance spectra of Solar System small bodies
No full textContext. The Gaia mission of the European Space Agency (ESA) has been routinely observing Solar System objects (SSOs) since the beginning of its operations in August 2014. The Gaia data release three (DR3) includes, for the first time, the mean reflectance spectra of a selected sample of 60 518 SSOs, primarily asteroids, observed between August 5, 2014, and May 28, 2017. Each reflectance spectrum was derived from measurements obtained by means of the Blue and Red photometers (BP/RP), which were binned in 16 discrete wavelength bands. For every spectrum, the DR3 also contains additional information about the data quality for each band. Aims. We describe the processing of the Gaia spectral data of SSOs, explaining both the criteria used to select the subset of asteroid spectra published in Gaia DR3, and the different steps of our internal validation procedures. In order to further assess the quality of Gaia SSO reflectance spectra, we carried out external validation against SSO reflectance spectra obtained from ground-based and space-borne telescopes and available in the literature; we present our validation approach. Methods. For each selected SSO, an epoch reflectance was computed by dividing the calibrated spectrum observed by the BP/RP at each transit on the focal plane by the mean spectrum of a solar analogue. The latter was obtained by averaging the Gaia spectral measurements of a selected sample of stars known to have very similar spectra to that of the Sun. Finally, a mean of the epoch reflectance spectra was calculated in 16 spectral bands for each SSO. Results.Gaia SSO reflectance spectra are in general agreement with those obtained from a ground-based spectroscopic campaign specifically designed to cover the same spectral interval as Gaia and mimic the illumination and observing geometry characterising Gaia SSO observations. In addition, the agreement between Gaia mean reflectance spectra and those available in the literature is good for bright SSOs, regardless of their taxonomic spectral class. We identify an increase in the spectral slope of S-type SSOs with increasing phase angle. Moreover, we show that the spectral slope increases and the depth of the 1 μm absorption band decreases for increasing ages of S-type asteroid families. The latter can be interpreted as proof of progressive ageing of S-type asteroid surfaces due to their exposure to space weathering effects.Astrodynamics & Space Mission
Perancangan dan Implementasi Perangkat Lunak Portal myITS SSO Menggunakan Pendekatan Micro Front-end
No full textSaat ini, sebuah laman web sering kali menampilkan fungsionalitas yang berasal dari lintas domain. Namun, pendekatan yang sering digunakan saat ini adalah implementasi front-end yang berarsitektur monolitik dengan semua fungsionalitas tergabung pada kode dan deployment yang sama. Implementasi tersebut dapat mengalami masalah seiring dengan kompleksnya tampilan pada front-end. Hal ini menjadi permasalahan pada Portal myITS yang menampilkan informasi mengenai kalender, berita, daftar kegiatan, dan portal akses login ke aplikasi-aplikasi yang ada di ITS menggunakan metode Single-Sign On. Sebagai solusi, penulis mengusulkan untuk menerapkan pendekatan micro front-end yang memperluas konsep microservices dan menerapkannya pada front-end. Dengan pendekatan ini, domain yang ada akan dipecah menjadi beberapa sub domain kemudian setiap sub domain memiliki front-end masing-masing yang kemudian diintegrasikan dalam satu tampilan. Selain itu, penulis juga akan menganalisis beberapa kerangka kerja untuk implementasi micro front-end sehingga di akhir dapat ditemukan kerangka kerja yang cocok untuk micro-frontend. Arsitektur micro front-end yang digunakan pada pengembangan Portal myITS SSO bertujuan untuk mempermudah maintainability karena setiap tim dapat mengembangkan fitur secara independen. Dengan pendekatan ini, deployment dari setiap layanan dapat dipisahkan ke beberapa mesin, sehingga meningkatkan modifiability dengan memungkinkan perubahan pada satu layanan tanpa mempengaruhi layanan lainnya. Dengan menerapkan pendekatan micro front-end, Portal myITS SSO dapat lebih mudah diperbarui dan dikembangkan tanpa mengganggu keseluruhan sistem. Hasil dari tugas akhir ini adalah sistem yang lebih efektif dan efisien.
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Currently, a web page often displays functionality that comes from cross-domain sources. However, the approach commonly used today is a monolithic front-end architecture where all functionality is combined in the same code and deployment. This implementation can experience problems as the front-end display becomes more complex. This is a problem for the myITS Portal, which displays information about calendars, news, event lists, and a login access portal to applications at ITS using the Single-Sign On method. As a solution, the author proposes to implement a micro front-end approach that extends the concept of microservices and applies it to the front-end. With this approach, the existing domain will be divided into several subdomains, each with its own front-end that is then integrated into a single display. In addition, the author will also analyse several frameworks for implementing micro front ends so that in the end a suitable framework for micro-frontends can be found. The micro front-end architecture used in the development of Portal myITS SSO aims to facilitate maintainability as each team can independently develop features. With this approach, the deployment of each service can be separated into multiple machines, thereby increasing modifiability by allowing changes to one service without affecting others. By implementing the micro front-end approach, Portal myITS SSO can be easily updated and developed without disrupting the entire system. The result of this final project is a more effective and efficient system
Perancangan sistem absensi siswa dengan menerapkan SSO (Single sign on) di SMKN 1 Lembah Melintang
No full textThe author conducted research at SMK Negeri 1 Lembah Melintang that in the implementation of the student attendance process at SMKN 1 Lembah Melintang it was deemed not optimal, this was because the system used was still manual. With the existing problems, several problems arise, especially in the student attendance process. Therefore, a system is needed that will make it easier for teachers to attend students at SMKN 1 Lembah Melintang. The making of this student attendance system uses the PHP/MySql programming language with the research method used, namely Research and Development (R&D). The model used is the ADDIE version (analyze, design, develop, implement, and evaluate) by applying the waterfall. And to test the product, the author uses the validity test, practicality test and effectiveness test. Based on the research that has been done, a student attendance system is produced by implementing SSO (single sign on) at SMKN 1 Lembah Melintang. The results of the validity tests that have been carried out by 3 validators, namely computer science experts regarding this product, obtained a value of 0.75, which is valid. The results of the practicality test conducted by 2 teachers of SMK Negeri 1 Lembah Melintang with a value of 1.03 which is very practical. And the results of the effectiveness test with 10 teachers obtained a value of 0.85 which is very effective
A critical review
No full textCastelli, M., Manzoni, L., Mariot, L., Nobile, M. S., & Tangherloni, A. (2022). Salp Swarm Optimization: A critical review. Expert Systems with Applications, 189, 1-12. [116029]. [Advanced online publication on 16 October 2021]. Doi: https://doi.org/10.1016/j.eswa.2021.116029.---%ABS1% ---Funding Information: This work was supported by national funds through the FCT (Fundação para a Ciência e a Tecnologia), Portugal by the projects GADgET ( DSAIPA/DS/0022/2018 ) and the financial support from the Slovenian Research Agency, Republic of Slovenia (research core funding no. P5-0410 ).In the crowded environment of bio-inspired population-based metaheuristics, the Salp Swarm Optimization (SSO) algorithm recently appeared and immediately gained a lot of momentum. Inspired by the peculiar spatial arrangement of salp colonies, which are displaced in long chains following a leader, this algorithm seems to provide an interesting optimization performance. However, the original work was characterized by some conceptual and mathematical flaws, which influenced all ensuing papers on the subject. In this manuscript, we perform a critical review of SSO, highlighting all the issues present in the literature and their negative effects on the optimization process carried out by this algorithm. We also propose a mathematically correct version of SSO, named Amended Salp Swarm Optimizer (ASSO) that fixes all the discussed problems. We benchmarked the performance of ASSO on a set of tailored experiments, showing that it is able to achieve better results than the original SSO. Finally, we performed an extensive study aimed at understanding whether SSO and its variants provide advantages compared to other metaheuristics. The experimental results, where SSO cannot outperform simple well-known metaheuristics, suggest that the scientific community can safely abandon SSO.authorsversionpublishe
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