• Economic and Environmental Geology
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• v.21 no.2
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• pp.185-191
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• 1988

A two channel seismic recorder suitable for long-term observation of microearthquakes is developed. The direct analogue recording on cassette tape is adopted in the recorder whose circuits of amplifier and mortor units of an audio cassette recorder are modified. The recorder provides contineous record of 10 days with DC 12V battery (100AH) and with standard cassette tape of 60 minute use. The binary coded time signals of date, hour, and minute are generated once a minute by the timing system and absolute time input using radio to measure the time drift is also possible. For the seismic signal processing, the analogue signals from audio cassette player pass A/D converter and digitized data are stored in personal computer. Then visual records can be obtained using computer graphic mode. Basic programs "ADCONVO" and "DRAWO" to accomplish A/D conversions, the creation of data files and visualization of signals were written. Some sample signals reproduced from the recorded tape are presented.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.6
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• pp.606-611
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• 2014

The understanding of another's behavior is a fundamental cognitive ability for primates including humans. Recent neuro-physiological studies suggested that there is a direct matching algorithm from visual observation onto an individual's own motor repertories for interpreting cognitive ability. The mirror neurons are known as core regions and are handled as a functionality of intent recognition on the basis of imitative learning of an observed action which is acquired from visual-information of a goal-directed action. In this paper, we addressed previous works used to model the function and mechanisms of mirror neurons and proposed a computational model of a mirror neuron system which can be used in human-robot interaction environments. The major focus of the computation model is the reproduction of an individual's motor repertory with different embodiments. The model's aim is the design of a continuous process which combines sensory evidence, prior task knowledge and a goal-directed matching of action observation and execution. We also propose a biologically inspired plausible equation model.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.219-221
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• 2014

The objective of this paper is to simulate the dynamic behavior of a floating structure model, using image processing and close-range photogrammetry, instead of the contact sensors. Previously, the movement of structure was presented through the exterior orientation estimation of a single camera by space resection. The inverse resection yields the 6 orientation parameters of the floating structure, with respect to the camera coordinate system. The single camera solution is of interest in applications characterized by restriction in term of costs, unfavorable observation conditions, or synchronization demands when using multiple cameras. This article discusses the theoretical determinations of camera exterior orientation based on Direct Linear Transformation and photogrammetric resection using least squares adjustment. The proposed method was used to monitor the motion of a floating model. The results of six degrees of freedom (6-DOF) by inverse resection show that the appropriate initial values by DLT can be effectually applied in least squares adjustment, to obtain the precision of exterior orientation parameters. Additionally, a comparison between the close-range photogrammetry and total station results was feasibly verified. Therefore, the proposed method can be considered as an efficient solution to simulating the movement of floating structure.

• Journal of Magnetics
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• v.8 no.3
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• pp.108-112
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• 2003

We report the experimental finding that there exists a transition of magnetization reversal process with varying the applied field in Co/Pd multilayer. We have measured the wall-motion speed V and the nucleation rate R during magnetization reversal via time-resolved direct domain observation, where the magnetization reversal process of Co/Pd multilayer is found to take a transition from thermal activation process to viscous process at the critical field of about 1.87 H$\_$C/ (coercivity). In the thermal activation regime, we find that the field dependences of two activation volumes for the wall-motion process and the nucleation process are different with each other, which reveals that the wall-motion and nucleation experience completely different interactions. In the viscous regime, we find that the wall-mobility is much smaller than a typical value for the sandwiched Co films, which implies that the Co/Pd interfaces in multilayer substantially contribute to the dynamic dissipation.

• Ocean and Polar Research
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• v.43 no.3
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• pp.193-203
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• 2021

In-situ experiment using ocean buoys is a direct ocean observation and has been playing an important role from the past to the present based on high reliability. The ocean buoy is operated more stable than before due to the technological development of communication (GPS, satellite, …) and equipment, but still moored buoys are not free from various accidents occurring in the ocean. Nevertheless, there is currently a lack of countermeasures or manuals about mooring accidents. Therefore, in this study, based on the experience of operating buoys conducted for many years, the advantages and disadvantages of ocean buoys according to size were analyzed. and legal procedures before and after buoy mooring were presented to enhance the use of buoys. And it is suggested to realize successful experiment by proposing considerations before mooring the buoy in preparation for an accident.

• Journal of Korean Biological Nursing Science
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• v.20 no.4
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• pp.228-235
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• 2018

Purpose: This study aimed to investigate the clinical alarm occurrence and management of nurses toward clinical alarms in the intensive care unit (ICU). Methods: This observational study was conducted with 40 patients and nurses cases in two ICUs of a university hospital. This study divided 24 hours into the unit of an hour and conducted two times of direct observation per unit hour for 48 hours targeting the medical devices applied to 40 patients. Data were analyzed using IBM SPSS Statistics 23. Results: On average, 3.8 units of medical devices were applied for each patient and the ranges of alarm settings were wide. During 48 hours, 184 cases of clinical alarm were occurred by four types of medical devices including physiological monitors, mechanical ventilators, infusion pumps, and continuous renal replacement therapy. Among them, false alarm was 110 cases (59.8%). As for the alarm management by ICU nurses, two-minute alarm mute took up most at 38.0% (70 cases), and no response was second most at 32.6% (60 cases). When valid alarm sounded, nurses showed no response at 43.2%. Conclusion: The findings suggest that a standard protocol for alarm management should be developed for Korean ICU settings. Based on the protocol, continuous training and education should be provided to nurses for appropriate alarm management.

• Korean Journal of Metals and Materials
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• v.47 no.12
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• pp.787-796
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• 2009

The fracture toughness improvement of Ni-Mn-Ga-Fe ferromagnetic shape memory alloys containing ductile particles was explained by direct observation of microfracture processes using an in situ loading stage installed inside a scanning electron microscope (SEM) chamber. The Ni-Mn-Ga-Fe alloys contained a considerable amount of ductile particles in the grains after the homogenization treatment at $800{\sim}1100^{\circ}C$. ${\gamma}$ particles were coarsened and distributed homogeneously along {$\beta}$ grain boundaries as well as inside {$\beta}$ grains as the homogenization temperature increased. The in situ microfracture observation results indicated that ${\gamma}$ particles effectively acted as blocking sites of crack propagation, and provided stable crack growth that could be confirmed by the R-curve analysis. This increase in fracture resistance with increasing crack length improved overall fracture properties of the alloys containing ${\gamma}$ particles.

• Journal of Korean Elementary Science Education
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• v.35 no.2
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• pp.150-165
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• 2016

This study aims to analyze types of science museum worksheets developed by elementary pre-service teachers and their perspectives on the requirements and necessity of science museum worksheets. As analysis subjects, this study selected 38 kinds of worksheets and reports developed by 114 elementary pre-service teachers who were in the third year of university of education. In this study, the science museum selected for elementary pre-service teachers to develop worksheets was a national science museum, composed of 'Nature and Discovery Museum', 'Science Technology and Industry Museum' and 'Children's Museum', which was located in a metropolitan city and opened in 2013. The results of this study can be summarized as follows; Firstly, as a result of analyzing the science museum worksheets developed by elementary pre-service teachers, this study found out that the experience type with hands-on and observation techniques applied was most, and as an approach method, direct manipulation, look-in observation and close observation were most. However, although these science museum worksheets were experience-oriented, many of them were survey-oriented ones that suggested too many questions through various exhibits. Secondly, as a result of analyzing requirements of science museum worksheets elementary pre-service teachers thought and described through the word tree of NVivo 10, this study extracted 10 kinds of main themes, out of which the requirement, 'A limited amount of activity should be required', showed the highest frequency. Thirdly, as a result of analyzing the necessity of science museum worksheets elementary pre-service teachers thought and described through the word tree of NVivo 10, this study extracted 9 kinds of main themes, out of which the opinion, 'It is required to help students check an exhibit which may be passed by', was most.

• Korean Journal of Remote Sensing
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• v.28 no.4
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• pp.435-448
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• 2012

Evapotranspiration (ET) including evaporation from a land surface and transpiration from photosynthesis of vegetation is a sensitive hydrological factor with outer circumstances. Though both direct measurements with an evaporation pan and a lysimeter, and empirical methods using eddy covariance technique and the Bowen ratio have been widely used to observe ET accurately, they have a limitation that the observation can stand for the exact site, not for an area. In this study, remote sensing technique is adopted to compensate the limitation of ground observation using the Moderate Resolution Imaging Spectroradiometer (MODIS) multispectral sensor mounted on Terra satellite. We improved to evapotranspiration model based on remote sensing (Mu et al., 2007) and estimated Penman-Monteith evapotranspiration considering regional characteristics of Korea that was using only MODIS product. We validated evapotranspiration of Sulma (SMK)/Cheongmi (CFK) flux tower observation and calculation. The results showed high correlation coefficient as 0.69 and 0.74.

• Journal of Digital Convergence
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• v.13 no.12
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• pp.217-224
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• 2015

OBJECTIVES Handwashing rate of Korean people was lower than the rates of people in developed countries. The purpose of this study was to investigate handwashing rate, the factors influence people's handwashing behaviors during use of public restroom. METHODS This study used the data of '2013 Korea National Handwashing Survey'. The survey was done through direct observation on the user of subway and train station restroom from September 10 to 12, 2013. RESULTS Factors influencing handwashing with soap were administrative region(OR 0.490-2.255), purpose of toilet use(urination 1.000, defecation 2.505), drying method after handwashing(OR 0.497-3.107). CONCLUSIONS The results of this study will provide the evidence data of national handwashing promotion activities for preventing and controlling communicable diseases.