Circuit Structure and Control Method to Reduce Size and Harmonic Distortion of Interleaved Dual Buck Inverter

A new circuit structure and control method for a high power interleaved dual-buck inverter are proposed. The proposed inverter consists of six switches, four diodes and two inductors, uses a dual-buck structure to eliminate zero-cross distortion, and operates in an interleaved mode to reduce the current stress of switch. To reduce the total harmonic distortion at low output power, the inverter is controlled using discontinuous-current-mode control combined with continuous-current-mode control. The experimental inverter had a power-conversion efficiency of 98.5% at output power = 1300 W and 98.3% at output power = 2 kW, when the inverter was operated at an input voltage of 400 V-DC, output voltage of 220 V-AC/60 Hz, and switching frequency of 20 kHz. The total harmonic distortion was < 0.66%, which demonstrates that the inverter is suitable for high-power dc-ac power conversion.11Ysciescopu

A Study on Teleoperation of a Mobile Robot Using Haptic Feedback

Abstract. Haptic feedback force is often suggested to complement visual information through the sense of touch to improve efficiency and safety in the teleoperation of mobile robot. The efficiency and safety of teleoperation are strongly dependent upon how haptic feedback is presented to the operator. In this study a haptic feedback scheme for teleoperation of mobile robot is developed and its effectiveness is experimentally verified. Experimental results show that the developed scheme improves the quality of mobile robot teleoperation in terms of improvement in efficiency and safety

A Study on Teleoperation of a Mobile Robot Using Haptic Feedback

Abstract. Haptic feedback force is often suggested to complement visual information through the sense of touch to improve efficiency and safety in the teleoperation of mobile robot. The efficiency and safety of teleoperation are strongly dependent upon how haptic feedback is presented to the operator. In this study a haptic feedback scheme for teleoperation of mobile robot is developed and its effectiveness is experimentally verified. Experimental results show that the developed scheme improves the quality of mobile robot teleoperation in terms of improvement in efficiency and safety

Operad Structure of Poset Matrices

This paper examines operad structures derived from poset matrices by formulating a set of new construction rules for poset matrices. In this direction, eleven different partial composition operations will be introduced as the basis for the construction of poset matrices of any given size by extending the combinatorial setting of species of structures to poset matrices. Three of these partial composition operations are shown to define an operad structure for poset matrices. The structural properties of poset matrices and their duals are then studied based on their associated operad constructions.Comment: arXiv admin note: substantial text overlap with arXiv:2212.1164

Prediction of the Chemical Composition and Fermentation Parameters of Fresh Coarse Italian Ryegrass Haylage Using Near Infrared Spectroscopy

Italian ryegrass (Lolium multiflorum) is an annual forage grass species which is widely cultivated in South Korea. It grows extensively in the southern part of the country and is an important component of winter forage for livestock. Each year, in Korea, over one million hectares of Italian ryegrass is converted to round bale haylage. Quality control is an important field in forage utilization research and marketing, and involves the estimation of forage nutrient content. Wet chemistry is the traditional method used to analyze the nutrient content of forage. However, this technique is often destructive, expensive, and time consuming, and it is not suitable for real-time feedstuff analysis. Near infrared spectroscopy (NIRS), on the other hand, is an alternative technique that has several major advantages over traditional methods. The analysis of silage nutrient content, using NIR, conventionally includes the drying and milling of samples. However, these processes can lead to reduction of volatile acids, which are important components of silage. NIRS can be affected by spectral regions, drying and grinding methods, particle size, packing density and the temperature of samples (Reeves and Blosser, 1991). In order to obtain accurate NIRS results, sample preparation, and the measurement conditions of the calibration set and predicted samples, need to match. The objectives of this study were to (1) assess the usefulness of NIRS in determining the nutritional composition and fermentative parameters of fresh coarse samples of Italian ryegrass haylage, (2) assess the predictive value of various NIRS calibration models, and (3) explore cost-effective and time saving methods for forage quality estimation, in field populations

Efekti korišćenja astaksantina u ishrani na rast, pigmentaciju mišića i antioksidantne aktivnosti mlađi kalifornijske pastrmke (oncorhynchus mykiss)

This study was designed to test the effects of dietary astaxanthin on growth, muscle pigmentation, antioxidant activity and biochemical composition of juvenile rainbow trout (Oncorhynchus mykiss). Experimental diets were formulated to contain 50, 75 and 100 ppm astaxanthin (designed as AS50, AS75 and AS100). The diet without supplementation of astaxanthin was considered as the control diet. Each experimental diet was fed to three replicate groups of fish (18.5 g/fish) to visual satiation two times a day for 10 weeks. Growth performance and proximate composition of muscle of fish were not affected by dietary AS levels (P> 0.05). Total carotenoid concentration in the muscle of fish fed the AS50 diet was higher than that of fish fed the control diet, but no different to that of fish fed the AS75 and AS100 diets. The astaxanthin concentration in the muscle of fish fed AS50, AS75 and AS100 diets were higher than that of control diet. The redness (a*) of the muscle of fish fed AS50, AS75 and AS100 diets were higher than that of fish fed the control diet (P 0.05) nije uticao na performansu rasta i hemijski sastav mišića ribe. Ukupna koncentracija karotenoida u mišiću ribe koja je hranjena AS50 hranom bila je viša nego kod riba hranjenih kontrolnom hranom, ali nije bila drugačija od riba hranjenih AS75 i AS100 hranom. Koncentracija astaksantina u mišiću riba hranjenih AS50, AS75 i AS100 hranom bila je viša nego kod riba hranjenih kontrolnom hranom. Crvena boja (a*) mišića ribe koja je hranjena AS50, AS75 i AS100 hranom bila je jača nego kod ribe hranjene kontrolnom hranom (P< 0.05). Antioksidantna aktivnost DPPH, radikala hidroksila i alkila u plazmi i jetri riba nisu zavisili od nivoa astaksantina osim kod plazme koja je imala antioksidantnu aktivnost alkilnih radikala. Rezultati ove studije nagoveštavaju da se hrana koja sadrži 50 ppm astaksantina može koristiti da bi se poboljšala crvena boja mišične pigmentacije kod mlađi kalifornijske pastrmke

Effects of Bee Venom on Glutamate-Induced Toxicity in Neuronal and Glial Cells

Bee venom (BV), which is extracted from honeybees, is used in traditional Korean medical therapy. Several groups have demonstrated the anti-inflammatory effects of BV in osteoarthritis both in vivo and in vitro. Glutamate is the predominant excitatory neurotransmitter in the central nervous system (CNS). Changes in glutamate release and uptake due to alterations in the activity of glutamate transporters have been reported in many neurodegenerative diseases, including Parkinson's disease, Alzheimer's disease, and amyotrophic lateral sclerosis. To assess if BV can prevent glutamate-mediated neurotoxicity, we examined cell viability and signal transduction in glutamate-treated neuronal and microglial cells in the presence and absence of BV. We induced glutamatergic toxicity in neuronal cells and microglial cells and found that BV protected against cell death. Furthermore, BV significantly inhibited the cellular toxicity of glutamate, and pretreatment with BV altered MAP kinase activation (e.g., JNK, ERK, and p38) following exposure to glutamate. These findings suggest that treatment with BV may be helpful in reducing glutamatergic cell toxicity in neurodegenerative diseases

Growth characteristics and productivity of cold-tolerant “Kowinearly” Italian ryegrass in the northern part of South Korea

The objective of this research is to evaluate differences in growth characteristics and productivity between Kowinearly and Florida 80 Italian ryegrass varieties in regions with severely cold winters. This research was carried out in Suwon (in central South Korea) and Yonchun (in northern South Korea) during the 2002 2006 growing seasons. Kowinearly is a diploid variety with green leaf colour and a semi prostrate growth habit in autumn and a semi-erect one in spring. There were differences among the varieties in terms of cold tolerance, heading date, and forage yield in Yonchun. The winter field survival of Kowinearly was 85%, while that of Florida 80 was 43%. The dry matter yield of Kowinearly in Yonchun was 9,662 kg/ha, which was 31% more than that of Florida 80. In Suwon, the heading date of Kowinearly was May 7, which was 2 days later than that of Florida 80. In Yonchun, Kowinearly’s heading date was May 12, 1 day earlier than that of Florida 80. These results indicate that Kowinearly has good cold tolerance, and that in spring, it starts growth earlier than Florida 80, because of its higher cold tolerance.Keywords: Italian ryegrass, Kowinearly, cold tolerance, new variety, forage cro