Control of Rigid Robots Equipped with Brushed DC-Motors as Actuators

Victor,M.,Hernandez-Guzman,Victor,Santibanez,Gilberto,Herrera 제어로봇시스템학회 2007 International Journal of Control, Automation, and Vol.5 No.6

Effects of Surface Properties of Bacterial Poly(3-hydroxybutyrate-co-3- hydroxyvalerate) on Adhesion and Proliferation of Mouse Fibroblasts

Victor,N.,Vasilets,박기동,Valentina,A.,Surguchenko,Anna,S.,Ponomareva,Eugene,A.,Nemetz,Victor,I.,Sevastianov,배진우 한국고분자학회 2015 Macromolecular Research Vol.23 No.2

Adhesion and proliferation of NIH/3Т3 mouse fibroblasts on the surfaces of bacterial copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and its mixture with poly(ethylene glycol) with differing crystallinity, surfaceenergy, and mean roughness was investigated. The surface mean roughness of all films on both sides, at the air interfaceand at the glass interface, measured by atomic force microscopy, was higher (from 17.0±1.4 nm to 290.8±7.0 nm)than that of the tissue culture polystyrene control (9.5±0.6 nm). The structure, surface energy, and chemical compositionof bacterial films were studied by differential scanning calorimetry, contact angle measurements, and Fouriertransform infrared (FTIR) spectroscopy. After 48 h, cell proliferation on all surfaces was significantly less than onthe control substrate; however, after 72 and 96 h, cell proliferation was comparable with control on some surfaceswith sufficient roughness. Addition of poly(ethylene glycol) resulted in an increase of adhesion and the metabolicactivity of the cells, even for relatively smooth surfaces. The complex correlation of cell metabolic activity with surfaceenergy and crystallinity for “rough” (mean roughness >100 nm) and “smooth” (mean roughness < 100 nm) surfacesis discussed.

Local Condiment, Iru, Obtained from the Fermentation of Parkia biglobosa Seed Substantially Reduced the Serum Cholesterol Level of Wister Rats

Ayowole,Victor,Atere,Ayodeji,Adedeji,Afolabi,Clement,Akinmoladun,Victor,Olusegun,Oyetayo,Felix,Akinsola,Akinyosoye 한국식품영양과학회 2020 Preventive Nutrition and Food Science Vol.25 No.2

Hypercholesterolaemia is one of the risk factors in coronary heart disease. Hence, this research was designed to investigate the effect of iru on cholesterol levels in hypercholesterolaemic rats. The fermented condiment iru was produced naturally and with starter cultures of Lactobacillus plantarum, Bacillus subtilis, and Leuconostoc sp.. The hypercholesterolaemic rats were fed a diet supplemented with iru for 28 days, and total cholesterol, triglyceride (TG), high density lipoproteins (HDL), and low density lipoproteins (LDL) were determined before and after feeding. Cholesterol levels in hypercholesterolaemic rats (100.80 mg/dL) were reduced to 56.99∼80.21 ㎎/dL after feeding with iru supplementation while rats not placed on the iru diet had cholesterol levels of 119 ㎎/dL. There were also significant reductions (P<0.05) in serum TG (78.77∼32.57 ㎎/dL) and LDL (28.43∼6.63 ㎎/dL) levels in rats fed the iru diet compared with the control (63.36 ㎎/dL). Higher and significantly different (P<0.05) HDL was found in rats fed with iru fermented with L. plantarum (44.01 ㎎/dL) while the least was found in the untreated group (28.93 ㎎/dL). The results from this study suggest that supplementing the diet with iru obtained by the fermentation of Parkia biglobosa seeds may significantly reduce cholesterol level in the blood stream.

Control of Rigid Robots Equipped with Brushed DC-Motors as Actuators

Hernandez-Guzman,,Victor,M.,Santibanez,,Victor,Herrera,,Gilberto Institute of Control 2007 International Journal of Control, Automation, and Vol.5 No.6

We extend the application of an adaptive controller previously introduced in the literature under the assumption that no actuator dynamics exists to the case when the dynamics of the brushed DC-motors used as actuators is not neglected. Convergence to the desired positions is ensured without requiring any feedback to cope with the additional electric dynamics. The proposed control scheme does not require the exact knowledge of neither robot nor actuator parameters to select controller gains.

Advanced signal processing for enhanced damage detection with piezoelectric wafer active sensors

Victor,Giurgiutiu,Lingyu,Yu 국제구조공학회 2005 Smart Structures and Systems, An International Jou Vol.1 No.2

Advanced signal processing techniques have been long introduced and widely used in structural health monitoring (SHM) and nondestructive evaluation (NDE). In our research, we applied several signal processing approaches for our embedded ultrasonic structural radar (EUSR) system to obtain improved damage detection results. The EUSR algorithm was developed to detect defects within a large area of a thin-plate specimen using a piezoelectric wafer active sensor (PWAS) array. In the EUSR, the discrete wavelet transform (DWT) was first applied for signal de-noising. Secondly, after constructing the EUSR data, the short-time Fourier transform (STFT) and continuous wavelet transform (CWT) were used for the time-frequency analysis. Then the results were compared thereafter. We eventually chose continuous wavelet transform to filter out from the original signal the component with the excitation signal? frequency. Third, cross correlation method and Hilbert transform were applied to A-scan signals to extract the time of flight (TOF) of the wave packets from the crack. Finally, the Hilbert transform was again applied to the EUSR data to extract the envelopes for final inspection result visualization. The EUSR system was implemented in LabVIEW. Several laboratory experiments have been conducted and have verified that, with the advanced signal processing approaches, the EUSR has enhanced damage detection ability.

Development, the Second Time Around: The Political Logic of Developing Western China

Victor,Shin 동아시아연구원 2004 Journal of East Asian Studies Vol.4 No.3

As China's coastal region accelerate toward middle-income level, China's inland provinces remain mired in poverty and under-development. In 2000, the Chinese government embarked on an ambitious investment project to speed up growth in western China, aptly named “The Great Development of the West.” This paper compares the policy pattern of the Great Development program with policy patterns associated with the classical developmental state model. In doing so, this paper finds great discrepancies between the model and Chinese reality. Instead of implementing policies to nurture the export sector, build up human capital, and provide necessary infrastructure, the Great Development program allocated the vast sums to wasteful infrastructure projects that maximized the rent-seeking opportunities of local officials. From documentary sources, this paper finds that this pattern of allocation was intentional as political elites sought to consolidate power and expand jurisdiction.

La historia en caos en la obra de Reinaldo Arenas

Victor,Hugo,Cortes,Lopez 한국외국어대학교 외국종합연구센터 중남미연구소 2008 중남미연구 Vol.27 No.1

Hand- held Ultrasound Scanners in Medical Education: A Systematic Review

Victor,Galusko,Mohammed,Yunus,Khanji,Owen,Bodger,Clive,Weston,John,Chambers,Adrian,Ionescu 한국심초음파학회 2017 Journal of Cardiovascular Ultrasound Vol.25 No.3

Background: Ultrasound imaging devices are becoming popular in clinical and teaching settings, but there is no systematic information on their use in medical education. We conducted a systematic review of hand-held ultrasound (HHU) devices in undergraduate medical education to delineate their role, significance, and limitations. Methods: We searched Cochrane, PubMed, Embase, and Medline using the strategy: [(Hand-held OR Portable OR Pocket OR “Point of Care Systems”) AND Ultrasound] AND (Education OR Training OR Undergraduate OR “Medical Students” OR “Medical School”). We retained 12 articles focusing on undergraduate medical education. We summarised the patterns of HHU use, pooled and estimated sensitivity, and specificity of HHU for detection of left ventricular dysfunction. Results: Features reported were heterogeneous: training time (1–25 hours), number of students involved (1-an entire cohort), number of subjects scanned (27–211), and type of learning (self-directed vs. traditional lectures + hands-on sessions). Most studies reported cardiac HHU examinations, but other anatomical areas were examined, e.g. abdomen and thyroid. Pooled sensitivity 0.88 [95% confidence interval (CI) 0.83–0.92] and specificity 0.86 (95% CI 0.81–0.90) were high for the detection of left ventricular systolic dysfunction by students. Conclusion: Data on HHU devices in medical education are scarce and incomplete, but following training students can achieve high diagnostic accuracy, albeit in a limited number of (mainly cardiac) pathologies. There is no consensus on protocols best-suited to the educational needs of medical students, nor data on long-term impact, decay in proficiency or on the financial implications of deploying HHU in this setting.

Brazilian Test of Concrete Specimens Subjected to Different Loading Geometries

Victor,J.,Garcia,Carmen,O.,Marquez,Alonso,R.,Zuniga-Suarez,Berenice,C.,Zuniga-Torres,Luis,J.,Villalta-Granda 한국콘크리트학회 2017 International Journal of Concrete Structures and M Vol.11 No.2

The objective of this work was finding out the most advisable testing conditions for an effective and robust characterization of the tensile strength (TS) of concrete disks. The independent variables were the loading geometry, the angle subtended by the contact area, disk diameter and thickness, maximum aggregate size, and the sample compression strength (CS). The effect of the independent variables was studied in a three groups of experiments using a factorial design with two levels and four factors. The likeliest location where failure beginning was calculated using the equations that account for the stress–strain field developed within the disk. The theoretical outcome shows that for failure beginning at the geometric center of the sample, it is necessary for the contact angle in the loading setup to be larger than or equal to a threshold value. Nevertheless, the measured indirect tensile strength must be adjusted to get a close estimate of the uniaxial TS of the material. The correction depends on the loading geometry, and we got their mathematical expression and cross-validated them with the reported in the literature. The experimental results show that a loading geometry with a curved contact area, uniform load distribution over the contact area, loads projected parallel to one another within the disk, and a contact angle bigger of 12° is the most advisable and robust setup for implementation of BT on concrete disks. This work provides a description of the BT carries on concrete disks and put forward a characterization technique to study costly samples of cement based material that have been enabled to display new and improved properties with nanomaterials.

Volume yield, tree species diversity and carbon hoard in protected areas of two developing countries

Victor,Ajibola,Adekunle,Narayanan,K.,Nair,Awadhesh,K.,Srivastava,N.K.,Singh 한국산림과학회 2014 Forest Science And Technology Vol.10 No.2

The contributions of Protected Areas (PAs) in two developing countries (India and Nigeria) to biodiversity conservationand carbon accumulation were assessed in this study. Data were collected through field inventory from 12 plots(25 25 m) randomly located in each of the PAs. In each plot, all woody plants were identified and tree growth variableswere measured for trees with diameter at breast height 10 cm. We discovered that the two PAs are well stocked, matureand rich in tree species diversity with potentials for continuous growth as a result of the presence of young trees in thelower canopy. The biological diversity indices compared favorably with other similar PAs. The high above-groundbiomass and carbon of the tree species revealed the roles of PAs in climate change mitigation through CO2 absorption fromthe atmosphere. The difference in their phytosociological characteristics and carbon sink capacities, with higher valuesobtained for Nigerian forest, was attributed to the variation in geographical location, climatic conditions and soilproperties. The protection of these PAs should be enhanced for biodiversity conservation and climate change mitigation. The perceived challenges in developing countries with forest protection can be mitigated by introducing some institutionalpolicies and rural community involvement in forest management.