• Journal of the Korean Society of Tobacco Science
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• v.30 no.1
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• pp.1-7
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• 2008

Bacterial wilt caused by Ralstonia solanacearum has become a severe problem on tobacco in Korea. No effective single control measure is available at present time. One of the most potential way for controlling the bacterial wilt on tobacco is growing tobacco cultivars resistant to the bacterial wilt. In this study, optimal conditions for screening tobacco cultivars resistant to the bacterial wilt were examined to provide reproducible and efficient methods in growth chamber testing and field experiments for evaluating plant disease resistance. For this, already-known inoculation methods, inoculum densities, and incubation temperature, and plant growth stages at the time of inoculation were compared using tobacco cultivars resistant (Nicotiana tabacum cv, NC95), moderately resistant (N. tabacum cv. SPG70), and susceptible (N. tabacum BY4) to the bacterial disease. It was determined that root-dipping of tobacco seedlings at six true leaf stage into the bacterial suspension with inoculum level of $10^8$ colony-forming units (CFU)/ml for 20 min before transplanting was simple and most efficient in testing for resistance to the bacterial wilt of tobacco caused by R. solanacearum, for which disease incidences and severities were examined at 2 weeks of plant growth after inoculation at $20{\sim}25^{\circ}C$ in a growth chamber. These experimental conditions could discriminate one tobacco cultivar from the others by disease severity better than any other experimental conditions. In field testing, the optimum time for examining the disease occurrence was late June through early July. These results can be applied to establishing a technical manual for the screening of resistant tobacco cultivars against the bacterial wilt caused by R. solanacearum.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.1
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• pp.15-19
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• 2005

Conventional eddy current testing has been used for the detection of the defect-like fatigue crack in the conductive materials, such as aluminum, which uses a sinusoidal signal with very narrow frequency bandwidth, Whereas, the pulsed eddy current method uses a pulse signal with a broad bandwidth. This can allow multi-frequency eddy current testing, and the penetration depth is greater than that of the conventional eddy current testing. In this work, a pulsed eddy current instrument was developed for evaluating the metal loss. The developed instrument was composed of the pulse generator generating the maximum square pulse voltage of 40V, an amplifier controlled up to 52dB, an A/D converter of 16 bit and the sampling frequency of 20 MHz, and an industrial personal computer operated by the Windows program. A pulsed eddy current probe was designed as a pancake type in which the sensing roil was located inside the driving roil. The output signals of the sensing roil increased rapidly wich the step pulse driving voltage かn off, and the latter part of the sensing coil output voltage decreased exponentially with time. The decrement value of the output signals increased as the thickness of the aluminum test piece increased.

• Journal of Korean Society on Water Environment
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• v.39 no.1
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• pp.30-37
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• 2023

This study aimed to evaluate the ability to reduce flood damage caused by abnormal rainfall events due to climate change by utilizing a blue-green roof (BGF), a type of rooftop greening technology. For two buildings with the same roof area, a BGF was installed in the experimental group, a general roof was configured in the control group, and rainfall runoff was compared. A total of 10 rainfall events were tested and analyzed by classifying them into three rainfall classes (less than 10 mm, less than 100 mm, and more than 100 mm). There was a reduction of 100% in the case of 10 mm or less of rainfall, 84. 7% in the case of 100 mm or less, and 39.8% in the case of 100 mm or more. Although this study showed that a BGF was effective in reducing rainfall runoff, additional experiments and analyses of various factors affecting rainfall runoff reduction are needed to generalize the results of the study. This research methodology may be used to develop a method for evaluating the resilience of a BGF to flood damage due to climate change.

• Journal of Korean Neurosurgical Society
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• v.61 no.5
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• pp.539-547
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• 2018

Traumatic spinal cord injury (SCI) research has recently focused on the use of rat and mouse models for in vivo SCI experiments. Such small rodent SCI models are invaluable for the field, and much has been discovered about the biologic and physiologic aspects of SCI from these models. It has been difficult, however, to reproduce the efficacy of treatments found to produce neurologic benefits in rodent SCI models when these treatments are tested in human clinical trials. A large animal model may have advantages for translational research where anatomical, physiological, or genetic similarities to humans may be more relevant for pre-clinically evaluating novel therapies. Here, we review the work carried out at the University of British Columbia (UBC) on a large animal model of SCI that utilizes Yucatan miniature pigs. The UBC porcine model of SCI may be a useful intermediary in the pre-clinical testing of novel pharmacological treatments, cell-based therapies, and the "bedside back to bench" translation of human clinical observations, which require preclinical testing in an applicable animal model.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.2
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• pp.219-226
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• 2020

Nondestructive testing is one of the most commonly used quality inspection methods for evaluating ship structures. However, accurate evaluation is dif icult because various composite materials, such as reinforcements, resin, and fiber-reinforced plastics (FRPs), are used in hulls, and manufacturing quality differences are likely to exist owing to the fabrication environment and the skill level of workers. This possibility is especially true for FRP ships because they are significantly thicker than other structures, such as automobiles and aircraft, and are mainly manufactured using the hand lay-up method. Because the density of a material is a critical condition for ultrasonic inspection, in this study, a hull plate was selected from a vessel manufactured using e-glass fiber, which is widely used in the manufacture of FRP vessels with the weight fraction of the glass content generally considered. The most suitable ultrasonic testing conditions for the glass FRP hull plate were investigated using a pulse-echo ultrasonic gauge. A-scans were performed with three probes (1.00, 2.25, and 5.00 MHz), and the results were compared with those of the hull plate thickness measured using a Vernier caliper. It was found that when the probe frequency was higher, the eco-pulse velocity of the receiver had to be lowered to obtain accurate measurement results, whereas fewer errors occurred at a relatively low probe frequency.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.1
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• pp.13-21
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• 2017

This paper describes a design scheme of a system that tests or polls from the students at online class. By online test, the teacher can test the pre-knowledge level of the students and know how much students understand the lecture of the class. As the number of test increases, the burden of the preparation of setting question, evaluation of the test, and management of the test results is increased. In this environments, an online test management system make it easy to test and evaluate, and thus it would be a good tool for maintaining and managing the total procedure of the test or poll of the students. For evaluating the design of the system, we made a test system prototype and performed evaluations of the online test system. The online test and evaluation system provides a good tool for testing and evaluation of student's knowledge at the class with easy and fast way.

• International Journal of Naval Architecture and Ocean Engineering
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• v.2 no.2
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• pp.57-67
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• 2010

Experimental investigations were carried out on an Axi-symmetric Body Model fitted with Pump-jet Propulsor (PJP) in the Cavitation Tunnel at Naval Science and Technological Laboratory (NSTL). The tests were intended for evaluating the propulsion characteristics of the body and propulsor. The self propulsion point of the model for two configurations was determined after finding the corrections for tunnel blockage effects and differences in model length at zero trim. The results were found to match closely with the towing tank results. The rotor and stator torques also matched closely over full range of experiment. Further experiments were carried out on the body at $4.5^{\circ}$ angle of trim to investigate the propulsive performance and assess the operational difficulties in the sea. The results indicated an increase in resistance and decrease in rotor thrust; but the balance of torques between the rotor and stator was undisturbed, causing no concern to vehicle roll.

• International Journal of Automotive Technology
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• v.4 no.1
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• pp.47-55
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• 2003

The Center for Transportation Research at the Argonne National Laboratory (ANL) supports the DOE by evaluating advanced automotive technologies in a systems context. ha has developed a unique set of compatible simulation tools and test equipment to perform an integrated systems analysis project from modeling through hardware testing and validation. This project utilized these capabilities to demonstrate the trade-off in fuel economy and Oxides of Nitrogen (NOx) emissions in a so-called ‘pre-transmission’ parallel hybrid powertrain. The powertrain configuration (in simulation and on the dynamometer) consists of a Compression Ignition Direct Ignition (CIDI) engine, a Continuously Variable Transmission (CVT) and an electric drive motor coupled to the CVT input shaft. The trade-off is studied in a simulated environment using PSAT with different controllers (fuzzy logic and rule based) and engine models (neural network and steady state models developed from ANL data).

• 대한공업교육학회지
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• v.30 no.1
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• pp.1-18
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• 2005

The purpose of this study was to development a model of problem solving instruction for improving practical skill-competence in technical high school. For the study, various literature researches were reviewed intensively about problem solving process, laboratory instruction's approaches and learning principals. The problem solving instruction process was composed with identifying problems, generating alternative solutions, investigation and research, choosing a solution, acting on a plan, modeling of problem solving, testing and evaluating, redesigning and improving. The skills schema combines a four domain of skilled activity, that is, cognitive skills, psychomotor skills, reactive skills and interactive skills. The problem solving instruction was composed with five major learning systems-emotional, social, cognitive, physical, and reflective-that can be used extensively as generic lesson plashing. The teacher serves as a coach or guide for student learning. As a facilitator, the teacher challenges, questions, and stimulates the students in their thinking, problem solving and self-directed study. In this process, students represent problem with think aloud, assume responsibility for their learning and move from teacher-centered to student-centered education.

• Sleep Medicine and Psychophysiology
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• v.1 no.1
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• pp.29-35
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• 1994

Overall purposes of neuropsychological tests are summarized as follows: 1) Indentifying brain damage in individuals who have symptoms of uncertain etiology; 2) Assessing the extent and nature of deficits for forensic purposes and planning appropriate intervention; 3) Evaluating the effects of intervention or rehabilitation; 4) Examining the effects of various types of brain damage across different populations; and 5) Testing theoretical propositions about brain-behavior relationship. Of the neuropsychological tests, the Luria-Nebraska Neuropsychological Battery(LNNB) is easily transportable, relatively inexpensive, and performable by trained technician. The Korean version of LNNB is now being designed and will be used clinically in the near future. Localization and equipotential theories of brain function had been prevalent until Luria's theory of brain function. Brain, composed of three brain units in the theory, is the functional system in which each brain area has specific function and produce the function-related behavior. LNNB consists of 11 clinical scales, 5 summary scales, 8 localization scales, and 28 factor scales.