• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.12
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• pp.909-909
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• 2022

• Quality Improvement in Health Care
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• v.27 no.2
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• pp.18-29
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• 2021

Purpose: Patients with hematologic malignancy (HM) typically have a high mortality rate when their condition deteriorates. The chronic progressive course of the disease makes it difficult to assess the effect of intervention on acute events. We investigated the effectiveness of a rapid response team (RRT) on in-hospital mortality in patients with HM. Methods: We retrospectively analyzed the data of patients with HM who admitted to the medical intensive care unit between 2006 and 2015. Clinical outcomes before and after RRT implementation were evaluated. Results: A total of 228 patients in the pre-RRT period and 781 patients in the post-RRT period were included. The overall in-hospital mortality was 55.4%. Patients in the post-RRT period had improved survival; however, they required more vasopressor therapy, continuous renal replacement therapy, and extracorporeal membrane oxygenation. Multivariate analysis revealed that in-hospital mortality was associated with RRT activation (hazard ratio [HR], 0.634; 95% confidence interval [CI], 0.498-0.807; p < .001), neurological disease (HR, 2.007; 95% CI, 1.439-2.800; p < .001), sequential organ failure assessment score (HR, 1.085; 95% CI, 1.057-1.112; p < .001), need for continuous renal replacement therapy (HR, 1.608; 95% CI, 1.206-1.895; p< .001), mechanical ventilation (HR, 1.512; 95% CI, 1.206-1.895; p< .001), vasopressor (HR, 1.598; 95% CI, 1.105-2.311; p = .013), and extracorporeal membrane oxygenation (HR, 1.728; 95% CI, 1.105-2.311; p = .030). Conclusion: RRT activation may be associated with improved survival in patients with HM.

• Journal of the Korean Vacuum Society
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• v.11 no.4
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• pp.218-224
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• 2002

A domestic round robin test(RRT) for the quantitative analysis of minor impurities was performed by a standard procedure and standard reference material. The certified reference material(CRM)s for B-doped Si thin film and analysis specimens and the analysis specimens were prepared by an ion beam sputter deposition method. These samples were certified by inductively coupled plasma mass spectrometry(ICP-MS) with isotope dilution method which il one of the most quantitative methods in chemical analysis. By using an international standard procedure(ISO/DIS-l4237) for the quantitative analysis of B in Si by SIMS, a domestic RRT was performed for these specimens. Although only a few laboratories participated in this RRT, the average B concentration well agreed with the certified value within 2% error.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2237-2242
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• 2005

The original RRT is iteratively expanded by applying control inputs that drive the system slightly toward randomly-selected states, as opposed to requiring point-to-point convergence, as in the probabilistic roadmap approach. It is generally known that the performance of RRTs can be improved depending on the selection of the metrics in choosing the nearest vertex and bias techniques in choosing random states. We designed a path planning algorithm based on the RRT method for a remote-controlled mobile robot. First, we considered a bias technique that is goal-biased Gaussian random distribution along the command directions. Secondly, we selected the metric based on a weighted Euclidean distance of random states and a weighted distance from the goal region. It can save the effort to explore the unnecessary regions and help the mobile robot to find a feasible trajectory as fast as possible. Finally, the constraints of the actuator should be considered to apply the algorithm to physical mobile robots, so we select control inputs distributed with commanded inputs and constrained by the maximum rate of input change instead of random inputs. Simulation results demonstrate that the proposed algorithm is significantly more efficient for planning than a basic RRT planner. It reduces the computational time needed to find a feasible trajectory and can be practically implemented in a remote-controlled mobile robot.

• The Journal of Korea Robotics Society
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• v.14 no.4
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• pp.285-292
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• 2019

Path planning is an important problem to solve in robotics and there has been many related studies so far. In the previous research, we proposed the Heterogeneous-Ants-Based Path Planner (HAB-PP) for the global path planning of mobile robots. The conventional path planners using grid map had discrete state transitions that constrain the only movement of an agent to multiples of 45 degrees. The HAB-PP provided the smoother path using the heterogeneous ants unlike the conventional path planners based on Ant Colony Optimization (ACO) algorithm. The planner, however, has the problem that the optimization of the path once found is fast but it takes a lot of time to find the first path to the goal point. Also, the HAB-PP often falls into a local optimum solution. To solve these problems, this paper proposes an improved ant-inspired path planner using the Rapidly-exploring Random Tree-star ($RRT^*$). The key ideas are to use $RRT^*$ as the characteristic of another heterogeneous ant and to share the information for the found path through the pheromone field. The comparative simulations with several scenarios verify the performance of the improved HAB-PP.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.12
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• pp.1272-1277
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• 2014

This article describes a path planning algorithm for fixed-wing UAVs when a real terrain should be considered. Nowadays, many UAVs are required to perform mission flights near given terrain for surveillance, reconnaissance, and infiltration, as well as flight altitude of many UAVs are relatively lower than typical manned aerial vehicles. Therefore, real terrain should be considered in path planning algorithms of fixed-wing UAVs. In this research, we have extended a spline-$RRT^*$ algorithm to three-dimensional planner. The spline-$RRT^*$ algorithm is a $RRT^*$ based algorithm, and it takes spline method to extend the tree structure over the workspace to generate smooth paths without any post-processing. Direction continuity of the resulting path is guaranteed via this spline technique, and it is essential factor for the paths of fixed-wing UAVs. The proposed algorithm confirm collision check during the tree structure extension, so that generated path is both geometrically and dynamically feasible in addition to direction continuity. To decrease degrees of freedom of a random configuration, we designed a function assigning directions to nodes of the graph. As a result, it increases the execution speed of the algorithm efficiently. In order to investigate the performance of the proposed planning algorithm, several simulations are performed under real terrain environment. Simulation results show that this proposed algorithm can be utilized effectively to path planning applications considering real terrain.

• Korean Journal of Veterinary Service
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• v.44 no.3
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• pp.163-168
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• 2021

The rapid and reliable detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) plays a key role in isolating infected patients and preventing further viral transmission. In this study, we evaluated the clinical diagnostic performances of a commercial real-time reverse transcription loop-mediated isothermal amplification (RRT-LAMP) assay (Isopollo^® COVID-2 assay, M-monitor, Daegu, Korea) using eighty COVID-19 suspected clinical samples and compared these with the results of a commercial real-time reverse transcription polymerase chain reaction (RT-qPCR) assay (Allplex^TM 2019-nCoV rRT-QPCR Assay, SeeGene, Seoul, Korea). The results of the RRT-LAMP assay targeting the N or RdRp gene of SARS-CoV-2 showed perfect agreement with the RT-qPCR assay results in terms of detection. Furthermore, the RRT-LAMP assay was completed in just within a 20-min reaction time, which is significantly faster than about the 2 h currently required for the RT-qPCR assay, thus enabling prompt decision making regarding the isolation of infected patients. The RRT-LAMP assay will be a valuable tool for rapid, sensitive, and specific detection of SARS-CoV-2 in human or unexpected animal clinical cases.

• The Korean Journal of Applied Statistics
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• v.8 no.1
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• pp.9-26
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• 1995

In surveys on sensitive issues which respondents are unwilling to answer, response bias usually occur since respondents tend to answer untruthfully or evade answer. Warner(19650 introduced the Randomized Response Technique (RRT) which protected the privacy of the individual respondent to reduce these response biases. Though this technique are theoretically good it has some problems in applying this technique to field survey. Therefore in order to apply easily RRT to practical survey we present the practical plan through comparing and analyzing the several cases which RRT was applied. Also we take the field survey according to this plan.

• Clinical and Experimental Pediatrics
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• v.62 no.2
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• pp.43-47
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• 2019

Hyperammonemia can be caused by several genetic inborn errors of metabolism including urea cycle defects, organic acidemias, fatty acid oxidation defects, and certain disorders of amino acid metabolism. High levels of ammonia are extremely neurotoxic, leading to astrocyte swelling, brain edema, coma, severe disability, and even death. Thus, emergency treatment for hyperammonemia must be initiated before a precise diagnosis is established. In neonates with hyperammonemia caused by an inborn error of metabolism, a few studies have suggested that peritoneal dialysis, intermittent hemodialysis, and continuous renal replacement therapy (RRT) are effective modalities for decreasing the plasma level of ammonia. In this review, we discuss the current literature related to the use of RRT for treating neonates with hyperammonemia caused by an inborn error of metabolism, including optimal prescriptions, prognosis, and outcomes. We also review the literature on new technologies and instrumentation for RRT in neonates.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.266-292
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• 2007

Round Robin Test (RRT) on ground response analyses was conducted for three sites in Korea based on several site investigation data, which include borehole logs with the N values from standard penetration test (SPT) for all three sites and additionally cone tip resistance profiles for two sites. Three input earthquake motions together with the site investigation data were provided for the RRT. A total of 12 teams participating in this RRT presented the results of ground response analyses using equivalent-linear and/or nonlinear method. Each team determined input geotechnical properties by using empirical relationships and literatures based on own judgment, with the exception of the input motions. Herein, the characteristics of input motions were compared in terms of the frequency and period, and the selection of the depth to bedrock, on which the motions is impinged, was discussed considering geologic conditions in Korea. Furthermore, a variety of geotechnical properties such as shear wave velocity profiles and soil nonlinear curves were investigated with the input properties used in this RRT.