Vessel dynamic positioning (DP) systems are based on conventional PID-type controllers and an extended Kalman filter. However, they present a difficult tuning procedure, and the closed-loop ...performance varies with environmental or loading conditions since the dynamics of the vessel are eminently nonlinear. Gain scheduling is normally used to address the nonlinearity of the system. To overcome these problems, a sliding mode control was evaluated. This controller is robust to variations in environmental and loading conditions, it maintains performance and stability for a large range of conditions, and presents an easy tuning methodology. The performance of the controller was evaluated numerically and experimentally in order to address its effectiveness. The results are compared with those obtained from conventional PID controller.
The growing awareness of environmental issues and the requirements to establish solutions diminishing the impact on working environment as well as external environment has initiated ever increasing ...efforts to develop new, environmentally benign tribological systems for metal forming. The present paper gives an overview of these efforts substituting environmentally hazardous lubricants in cold, warm and hot forging as well as sheet forming and punching/blanking by new, less harmful lubricants and furthermore describes other measures directed towards the same goal such as development of anti-seizure tool materials and coatings and application of structured workpiece and tool surfaces.
The first Japanese strawberry cultivar, ‘Fukuba,’ was selected in 1899 from seedlings of ‘General Chanzy.’ Most of the Japanese forcing strawberry cultivars have ‘Fukuba’ in their ancestry. In ...general, the forcing cultivars have been raised from crosses among Japanese cultivars. American or European cultivars have rarely been used as breeding material in recent years. The present Japanese strawberry breeders are, however, concerned about the increase in inbreeding coefficient in Japanese strawberry cultivars and are suggesting that foreign gene sources should be used more for improvement of the forcing cultivars. Originally, Japanese strawberries were produced under open field culture, in which the fruits were harvested only in May. In Japan today, strawberry fruits are harvested all year round thanks to the development of various techniques that advance the harvesting time. However, production costs have also risen. Consequently, rationalization, such as cost reduction, is required for the forcing culture. Most of the cultivars used in summer-autumn culture are of an everbearing type. The everbearing cultivars differ in flowering behavior, namely, the strength of everbearing. In studies conducted on everbearing strength and the inheritance of the everbearing trait, we found that the node position of the first inflorescence in first-year runner plants is a suitable evaluation criterion for everbearing strength, and that the everbearing habit is regulated by a single dominant gene.
Metastasis is a critical factor contributing to poor prognosis in cancer, but the underlying mechanisms of metastasis are still poorly understood. We established a highly metastatic cell subline ...(HOC313-LM) derived from an oral squamous cell carcinoma cell line (HOC313) for uncovering the mechanisms of metastasis, and identified deoxyhypusine synthase (DHPS) as a metastasis-associated gene within the specific amplification at 19p13.2-p13.13 in HOC313-LM. DHPS-mediated hypusine-modification of eukaryotic translation factor 5A facilitated the translation of RhoA, resulting in the activation of the RhoA signaling pathway and leading to not only increased cell motility, invasion and metastasis of cancer cells in vitro, but also increased tumor growth in vivo. Moreover, the use of N1-Guanyl-1,7-diaminoheptane, a DHPS inhibitor, resulted in a significant decrease in tumor formation in vivo. In patients with esophageal squamous cell carcinoma (ESCC), overexpression of DHPS in ESCC tumors was significantly associated with worse recurrence-free survival, and correlated with distant metastasis. The elucidation of these molecular mechanisms within the hypusine cascade suggests opportunities for novel therapeutic targets in SCC.
Pt is an excellent and widely used hydrogen evolution reaction (HER) catalyst. However, it is a rare and expensive metal, and alternative catalysts are being sought to facilitate the hydrogen ...economy. As tungsten carbide (WC) has a Pt-like occupied density of states, it is expected to exhibit catalytic activity. However, unlike Pt, excellent catalytic activity has not yet been observed for mono WC. One of the intrinsic differences between WC and Pt is in their magnetic properties; WC is non-magnetic, whereas Pt exhibits high magnetic susceptibility. In this study, the WC lattice was doped with ferromagnetic Co nanocrystals to introduce an ordered-spin atomic configuration. The catalytic activity of the Co-doped WC was ∼30% higher than that of Pt nanoparticles for the HER during the hydrolysis of ammonia borane (NH
3
BH
3
), which is currently attracting attention as a hydrogen fuel source. Measurements of the magnetisation, enthalpy of adsorption, and activation energy indicated that the synergistic effect of the WC matrix promoting hydrolytic cleavage of NH
3
BH
3
and the ferromagnetic Co crystals interacting with the nucleus spin of the protons was responsible for the enhanced catalytic activity. This study presents a new catalyst design strategy based on the concept of an internal magnetic field. The WC-Co material presented here is expected to have a wide range of applications as an HER catalyst.
The catalytic activity of the Co-doped WC is 30% higher than that of Pt nanoparticles for the hydrogen evolution reaction arising from an internal magnetic field.
High-capacity Li-ion batteries were developed using the SiO-Si composite anode and lithium-rich layered oxide (LR-NMC) cathode in which the irreversible capacity of the anode can be compensated by ...that of the cathode rather than by conventional Li pre-doping process using lithium metal foil. The irreversible capacity of the anode could be adjusted by preparing a composite anode with the SiO and Si in which the irreversible capacity was equalized to that of the cathode at a Si/(SiO + Si) mass ratio of 0.8. The cell using the composite anode displayed a discharge capacity of 182 mAh g−1 as the cathode capacity at the 0.1C-rate, and a stable cycle performance for over 100 cycles with a discharge capacity of ca. 150 mAh g−1 at the 0.5C-rate and 30°C. The cell also displayed a stable cycle performance at 60°C the same as that at 30°C, and no drastic degradation even at 80°C. Furthermore, the cell can even be discharged at −55°C. The cell could discharge even at the 10C-rate. No thermal runaway was observed during the nail penetration test for the 1000 mAh cell. The cell can be used as the power source of a remote control quadcopter.
Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is one of the most serious diseases of soybean. The soybean landraces PI 594767A, PI 587905 and PI 416764 previously showed high levels of ...resistance to a wide range of ASR fungus, while the genetic basis of the resistance has yet to be understood. In this study, the ASR resistance loci were mapped using three independent mapping populations, POP‐1, POP‐2 and POP‐3 derived from crosses BRS184 × PI 594767A, BRS184 × PI 587905 and BRS184 × PI 416764, respectively. In each population, the resistance to ASR segregated as a single gene, but the resistance was dominant in PI 594767A and PI 587905 and incompletely dominant in PI 416764. The resistance genes from both PI 594767A and PI 587905 were mapped on chromosome 18 corresponding to the same location as known resistance locus Rpp1. Quantitative trait locus (QTL) analysis performed on POP‐3 identified the putative ASR resistance locus in PI 416764 on the defined region of chromosome 6 where Rpp3 was located. The QTLs detected by the mapping explained about 67–72% of the phenotypic variation in POP‐3. Cluster analysis based on disease reactions to 64 ASR populations demonstrated the presence of at least two types of functional resistant Rpp1 alleles: strong and weak allele(s), e.g. soybean accession PI 594767A and PI 587905 carry the strong resistant Rpp1 allele(s). Introducing or pyramiding strong Rpp1 allele(s) in elite soybean cultivars is expected to be useful against the South American rust population.
Objectives: The purpose of this study was to evaluate the antibacterial effect of silver-zeolite (SZ) against oral bacteria under anaerobic conditions.
Methods: The antibacterial activity of SZ was ...evaluated by determining the minimum inhibitory concentrations (MICs) using two-fold serial dilutions of SZ in Brain Heart Infusion broth. Release of Ag
+ into the broth was measured by an atomic absorption technique.
Results: SZ inhibited the growth of the bacteria tested under anaerobic conditions. The MIC of SZ ranged between 256 and 2048
μg/ml, which corresponded to a range of 4.8–38.4
μg/ml of Ag
+. All strains grew in broth containing 16,384
μg/ml of type-A zeolite.
Significance: These results suggested that SZ may be a useful vehicle to provide antibacterial activity to dental materials used even under anaerobic conditions such as deep in the periodontal pocket.
Liquid metal is used to tune the operational frequency of a monopole antenna by adjusting its length. The centre frequency can be continuously tuned over two octaves, 2.0–9.5 GHz, while maintaining a ...gain of ∼5.2 dBi.
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