The Basic Study of Underwater Robot Control for Over Actuated Systems

In general, only six individual thrusters are required to perform 6 DOF (Degree Of Freedom) motion. Sometimes, however, more than six thrusters are used for 6 DOF motion for a variety of purposes. The over actuated systems can transit quickly from transient state caused by disturbance to steady state through the over actuated input. So in the underwater robot, the purpose of over actuated system is mainly used to maintain stable motion and position. And that systems are performed to obtain the optimal efficiency through the thruster force distribution. In this paper, we designed and fabrication the ROV (Remotely Operated Vehicle) for the basic study of over actuated underwater robot. It has 4 horizontal thrusters and 4 vertical thrusters. Using this system, we derived the thruster force distribution matrix for thruster allocation. Also, to check the kinetic characteristics of over actuated underwater robot before applying various controller, we performed the basic motion performance test and motion control test using the PD controller in the indoor engineering water basin

Analysis of the Correlation Between the Support Performance of Supported Business for the Regional Industry

Reflecting the conditions and characteristics of Korea, the region's main industry is being developed to expand new job creation in the region and enhance the competitiveness of local industries. The local main business is supported to 63 main industries selected by region. The main industries in Busan include digital contents, intelligent machine parts, super precision convergence parts, mold heat treatment, and bio-health. In this study, the main industries of Busan region in 2016 conducted an analysis on the companies that support the intelligent machine parts industry. For the analysis, we collected data on the sales of supported companies, sales after business support, and employment growth. The analysis tool utilized IBM SPSS statistics 18. As a result, we confirmed the relationship between employment and sales according to support business programs. Based on the results of this study, it will be helpful for the task performing organization to identify the direction of the support program and the needs of the enterprise

Flow Analysis of Underwater Water Jet System Using Computational Fluid Dynamics and Particle Image Velocimetry

The width and depth of excavation are important for the development of a water jet system for underwater surface excavation in the water. This is determined by the pressure distribution affecting the ground. Therefore, it is necessary to analyze the flow of the water jet, but it is difficult to grasp visually, and generally used sensors are difficult to use in water. To overcome this problem, the flow analysis was simulated by using Computational Fluid Dynamics(CFD), Particle Image Velocimetry(PIV) experiment was performed to confirm the accuracy of CFD and to visualize the nozzle flow. The CFD was simulated by using MIDAS NFX and various pressures of nozzle injection, velocity distribution and pressure distribution were analyzed. For the PIV experiment, the water jet system is installed at L22m x W3.5m x D3m water tank, and a 5W Nd-yag laser was installed at the surface of the water, and a high-speed camera was installed to capture the flow in the side observation field. And particles of 20 micrometer size were mixed in the water. In the results of the CFD simulations, the nozzle injection pressure which is the measurable velocity by the PIV system was selected, the nozzle flow was visualized and the velocity distribution was measured by using the PIV experiment. The velocity distribution measured by PIV is compared with the CFD - analyzed velocity distribution under the same conditions

Time Series Analysis of Outcomes for Small and Medium Enterprises’ Support of Regional Industry

Continued investment in Research and Development (R&D) by the government and corporate support played a major role in the rapid growth of the Republic of Korea. In 2017, the amount of R&D investment by the government accounted for 19.7 trillion Won (KRW), which is 4.7 % of the government’s budget. The government’s R&D budget is increasing by 2.5 % each year. We analyzed the outcomes of the projects, supported by the Busan regional companies conducted in 2016 to 2017. For a time series analysis, we gathered companies support amount by year, sales after company support, and material for employment. We used IBM’s Statistical Package for the Social Sciences (SPSS) 18 for correlation analysis. We confirmed the relationship between employment and the sales of the annual company support program

Association of Low-Dose Exposure to Persistent Organic Pollutants with Global DNA Hypomethylation in Healthy Koreans

BACKGROUND: Global DNA methylation levels have been reported to be inversely associated with blood levels of persistent organic pollutants (POPs), xenobiotics that accumulate in adipose tissue. Whether these associations extend to a population with much lower concentrations of POPs is not known. OBJECTIVES: This study was performed to examine whether low-dose exposure to POPs was associated with global DNA hypomethylation in Koreans. METHODS: The amount of global DNA by hypomethylation was estimated by the percent 5-methyl-cytosine (%5-mC) in Alu and LINE-1 assays in 86 apparently healthy Koreans. Among various POPs, organochlorine (OC) pesticides, polychlorinated bipheryls (PCBs), and polybrominated dipherylethers (PBDEs) were measured. RESULTS: Most OC pesticides were inversely and significantly associated with %5-mC in the Alu assay, with correlation coefficients in the range -0.2 to -0.3 after adjusting for age, sex, body mass index, smoking, and alcohol. The strongest OC pesticide associations with %5-mC in the Alu assay were observed with oxychlordane, trans-nonachlor, and p,p'-dichlorodiphenyldichloroethylene. The correlation coefficient of age with %5-mC in the Alu assay was -0.24, similar to correlations of OC pesticides with %5-mC in the Alu assay. Most PCBs and PBDEs showed nonsignificant inverse trends with %5-mC in the Alu assay, but for some PCBs the U-shaped association was significant. On the other hand, POPs were not associated with %5-mC in the LINE-1 assay. CONCLUSIONS: We found that low-dose exposure to Pops, in particular OC pesticides, was associated with global DNA hypomethylation in apparently healthy Koreans.open1195102sciescopu

The Use of T1 Sagittal Angle in Predicting Cervical Disc Degeneration

Study DesignRetrospective evaluation.PurposeTo analyze the effect of T1 slope on degree of degeneration in patients with cervical disc degeneration.Overview of LiteratureThe T1 slope is well known parameter that may be very useful in evaluating sagittal balance. There are no reports on the analysis of the relationship between T1 slope and cervical disc degeneration. We hypothesized that T1 slope has an effect on the degree of cervical degeneration.MethodsSixty patients who had cervical spine magnetic resonance imaging (MRI) in our orthopedic clinic were enrolled. Patients were divided into two groups according to T1 slope. Radiologic parameters obtained from radiography and cervical spine MRI were compared between low T1 slope group (≤25) and high T1 slope group (>25).ResultsAmong low T1 slope group, average degeneration grade of each cervical segment was 2.65 in C2-3, 2.50 in C3-4, 2.62 in C4-5, 3.23 in C5-6, and 2.81 in C6-7. And that of high T1 group was 2.35 in C2-3, 2.32 in C3-4, 2.59 in C4-5, 2.79 in C5-6, and 2.32 in C6-7. Grade of degeneration of low T1 group was significantly higher, as compared with high T1 group in C5-6 (p=0.028) and C6-7 (p=0.009). Percentage of high grade degeneration of more than grand III was 65.4% in low T1 group and 32.4% in high T1 group (p=0.018). Risk of high grade degeneration of C6-7 was significantly higher in low T1 group (odds ratio, 5.63; 95% confidence interval, 1.665-19.057; p=0.005).ConclusionsPatients with low T1 slope had higher grade of degeneration regardless of age and gender. Low T1 slope is a potential risk factor of cervical spondylosis especially in the C6-7 cervical segment

Predictive value of progression-related gene classifier in primary non-muscle invasive bladder cancer

<p>Abstract</p> <p>Background</p> <p>While several molecular markers of bladder cancer prognosis have been identified, the limited value of current prognostic markers has created the need for new molecular indicators of bladder cancer outcomes. The aim of this study was to identify genetic signatures associated with disease prognosis in bladder cancer.</p> <p>Results</p> <p>We used 272 primary bladder cancer specimens for microarray analysis and real-time reverse transcriptase polymerase chain reaction (RT-PCR) analysis. Microarray gene expression analysis of randomly selected 165 primary bladder cancer specimens as an original cohort was carried out. Risk scores were applied to stratify prognosis-related gene classifiers. Prognosis-related gene classifiers were individually analyzed with tumor invasiveness (non-muscle invasive bladder cancer [NMIBC] and muscle invasive bladder cancer [MIBC]) and prognosis. We validated selected gene classifiers using RT-PCR in the original (165) and independent (107) cohorts. Ninety-seven genes related to disease progression among NMIBC patients were identified by microarray data analysis. Eight genes, a progression-related gene classifier in NMIBC, were selected for RT-PCR. The progression-related gene classifier in patients with NMIBC was closely correlated with progression in both original and independent cohorts. Furthermore, no patient with NMIBC in the good-prognosis signature group experienced cancer progression.</p> <p>Conclusions</p> <p>We identified progression-related gene classifier that has strong predictive value for determining disease outcome in NMIBC. This gene classifier could assist in selecting NMIBC patients who might benefit from more aggressive therapeutic intervention or surveillance.</p

Sequencing and characterization of Varicella-Zoster virus vaccine strain SuduVax

<p>Abstract</p> <p>Background</p> <p>Varicella-zoster virus (VZV) causes chickenpox in children and shingles in older people. Currently, live attenuated vaccines based on the Oka strain are available worldwide. In Korea, an attenuated VZV vaccine has been developed from a Korean isolate and has been commercially available since 1994. Despite this long history of use, the mechanism for the attenuation of the vaccine strain is still elusive. We attempted to understand the molecular basis of attenuation mechanism by full genome sequencing and comparative genomic analyses of the Korean vaccine strain SuduVax.</p> <p>Results</p> <p>SuduVax was found to contain a genome that was 124,759 bp and possessed 74 open reading frames (ORFs). SuduVax was genetically most close to Oka strains and these Korean-Japanese strains formed a strong clade in phylogenetic trees. SuduVax, similar to the Oka vaccine strains, underwent T- > C substitution at the stop codon of ORF0, resulting in a read-through mutation to code for an extended form of ORF0 protein. SuduVax also shared certain deletion and insertion mutations in ORFs 17, 29, 56 and 60 with Oka vaccine strains and some clinical strains.</p> <p>Conclusions</p> <p>The Korean VZV vaccine strain SuduVax is genetically similar to the Oka vaccine strains. Further comparative genomic and bioinformatics analyses will help to elucidate the molecular basis of the attenuation of the VZV vaccine strains.</p

Comparison of Clopidogrel and Ticlopidine/Ginkgo Biloba in Patients With Clopidogrel Resistance and Carotid Stenting

Background and Purpose: Patients undergoing carotid artery stenting (CAS) who show low responsiveness to clopidogrel may have a higher risk of peri-procedural embolic events. This study aimed to compare the effectiveness and safety of clopidogrel and ticlopidine plus Ginkgo biloba in clopidogrel-resistant patients undergoing CAS.Methods: In this multi-center, randomized, controlled trial, we used platelet reactivity test to select patients undergoing CAS who showed clopidogrel resistance, and compared treatments using clopidogrel and ticlopidine plus ginkgo. The primary outcome was the incidence of new ischemic lesion in the ipsilateral hemisphere of CAS. Detection of microembolic signal on transcranial Doppler was the secondary outcome. The clinical outcomes were also monitored.Results: This trial was discontinued after 42 patients were randomized after preplanned interim sample size re-estimation indicated an impractical sample size. The primary endpoint occurred in 12/22 patients (54.5%) in the clopidogrel group and 13/20 patients (65.0%) in the ticlopidine–ginkgo group (P = 0.610). No significant differences in the presence of microembolic signal (15.0 vs. 11.8%, P = 0.580), clinical outcomes (ischemic stroke or transient ischemic attack, 0.0 vs. 5.5%; acute myocardial infarction 0.0 vs. 0.0%; all-cause death, 4.5 vs. 0.0%), or incidence of adverse events were found in the two groups. In terms of resistance to clopidogrel, treatment with ticlopidine–ginkgo significantly increased the P2Y12 Reaction Units (difference, 0.0 [−0.3–3.0] vs. 21.0 [6.0–35.0], P &lt; 0.001).Conclusions: In patients who showed clopidogrel resistance, ticlopidine–ginkgo treatment was safe and increased P2Y12 Reaction Units; however, compared to clopidogrel, it failed to improve surrogate and clinical endpoints in patients undergoing CAS. This multimodal biomarker-based clinical trial is feasible in neurointerventional research.Clinical Trial Registration:http://www.clinicaltrials.gov. Unique identifier: NCT02133989