• Journal of Korean society of Dental Hygiene
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• v.17 no.6
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• pp.1067-1080
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• 2017

Objectives: This study analyzed the perception towards clinical practice education content held by dental hygiene students in dental institutions and their perceived importance of dental hygienists' clinical duties. Methods: The subjects of this study were 182 dental hygienists who were working at dental institutions in Seoul, Gyeonggi, and Chungcheong areas. A survey was conducted with a self-administered questionnaire. In the questionnaire, the clinical practice contents were classified into observation, preparation, and performance, and the importance of clinical duty was measured with a 3-point scale. For the clinical practice contents and the importance of duty, descriptive statistics and chi-square test were performed, and the study results were analyzed using STATA 11.0. Results: With regard to clinical practice contents, observation was mainly performed in oral & maxillofacilal radiology, preventive dentistry, periodontal medicine and oral medicine. In primary care and infection control, practice and observation were mainly performed. In the department of orthodontics and pediatric dentistry, observation and preparation were mainly conducted, while in oral surgery, conservative dentistry observation, preparation and practice were all conducted. With regard to clinical practice contents according to the dental institution, there were statistically significant differences in the type of dental institution and the duty (p>0.05). In terms of the importance of dental hygienist's duty, infection control, toothbrushing education for each patient, removal of plaque, and patient education after surgery were considered important. Conclusions: For clinical practice of the dental hygiene department, the education contents should be standardized in accordance with the importance of the dental hygienist's duty, a protocol for operation of practice should be developed, and a method of standardization of evaluation should be sought in the future.

• Journal of Biosystems Engineering
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• v.30 no.3 s.110
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• pp.135-140
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• 2005

Vegetable transplanting operation has been wholly depended on human labor that needs 18.4 hrs per 10 acres in Korea. Since periods of vegetable transplanting operations are limited, their mechanization has been strongly demanded. This study was conducted to develop a transplanting device that was the core technology for vegetable transplanter. In order to find out transplanting track and velocity of transplanting device, a kinematic analysis software was employed. Evaluation of prototype was carried out in the circular soil bin with high speed camera. Rotary type transplanting device produced an elliptic loci when two links of different lengths were moving to the opposite direction. The length of two links was 75mm and 44mm, respectively. Maximum displacement of rotary type transplanting device was 238mm. It seemed that the transplanting elliptic loci of transplanting device were identical between the simulation output generated by kinematic analysis software and the circular soil bin test result with a high speed camera. The rotary type transplanting device can be suitable fur transplanting short height vegetable, less than 20 cm length vegetables such as Chinese cabbage and cabbage, etc.

• Journal of Biosystems Engineering
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• v.30 no.4 s.111
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• pp.210-219
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• 2005

This study was conducted to solve the problem of crawled spinach harvesting that had been mainly done by manpower on the outdoor fields during the winter season. Moreover, there are not enough workers available for farming at most of rural areas in Korea because farming is getting hard and the number of old-aged workers is increasing. In order to find appropriate methods of digging, picking and collecting of spinach, the tests were examined outdoors. A prototype was designed based on the results of the tests and then fabricated for digging, picking-up and then collecting in continuous operation for harvesting spinach planted in the outdoor fields. In the field test with the prototype, the vibration intensity transmitted to the driver by vibrating blade was low while the vibrating blade reduced digging power by $46\%$ compared to that of the fixed blade. The spinach loss was found to be as low as $0.7\%$ in the condition of digging depth of 40 mm, cam rotational velocity of 748 rpm, and blade amplitude of 16.5 m. The working performance of the prototype spinach harvester was found to be 3.8 hour/10a resulting in $96\%$ of labor saving and $85\%$ of operating cost compared to the conventional manual harvesting.

• Journal of Environmental Science International
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• v.28 no.12
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• pp.1133-1145
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• 2019

Successful launch requires state-of-the-art launch vehicle technology and constant test operations, However, the meteorological threat to the launch vehicle flight trajectory is also an important factor for launch success. Atmospheric stability above the Naro Space Center at the this time is very important, especially because the initial flight operation can determine the success of the launch. Moreover, during the flight of launch vehicle with rapid pressure and thrust into the atmosphere, convection activity in the atmosphere may create environmental conditions that cause severe weather threats such as thunderstorms. Hence, studies of atmospheric instability characteristics over the Naro Space Center are a necessary part of successful launch missions. Therefore, the main aims of this study were to (1) verify the atmospheric stability index and convection activity characteristics over the Naro Space Center using radiosonde data observed from 2007 to 2018 by the Naro Space Center, (2) analyze changes in the atmospheric stability index according to monthly and seasonal changes, and (3) assess how the calculated atmospheric stability index is related to actual thunderstorm occurrence using statistical analysis. Additionally, we aimed to investigate the atmospheric characteristics above the Naro Space Center through the distribution chart of the atmospheric stability index during summer, when convection activity is highest. Finally, we assessed the relationship between lightning occurrence and unstable atmospheric conditions, through predictability analysis performed using the lightning observation data of the Korea Meteorological Administration.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.4
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• pp.55-67
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• 2019

This study analyzed the fabric and product size of the burn patient's custom compression garment and measured the pressure applied by the garment to assess whether proper pressure is being delivered for treatment. The test clothes were presented to the market by body size and commissioned with the same design. The subjects selected four people close to the average body size of men in their 20s determined by 7th Size Korea. The experiment was conducted by wearing a compression suit, performing activities and measuring changes in the pressure of the garment according to changes in posture. The fabric used for the compressive clothing was not ruptured even at 216 kPa, the elasticity recovery rate was measured between 80.5 and 94.5%. The product dimensions of the experimental clothing varied by up to 8cm from brand to brand, requiring the standardization of compression clothing. The experiment showed that four types of compression suit varied in pressure, and the pressure range, excluding the gastric arm (17.9mmHg), was between 2.5-14.1mmHg, which failed to meet the level of pressurization for treatment purposes. The clothing pressure in the chest area dropped when performing movements rather than standing still. This was interpreted to be a result of reduced the adhesion of the compression suit during operation. The peak pressure (31.68mmHg) and the lowest pressure (2.2mmHg) was noted in the scapula, indicating that no pressure was being transmitted on the vertebrae. The pressure of the garment on the right shoulder blade was elevated in a supine position. Because much time is spent laying down, it is necessary for the pattern design to accommodate for the increased clothing pressure on the shoulder blades. Standardization of the level of pressurization for burn patient's custom-made pressure suits for each stage of treatment is urgently required.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.157-158
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• 1998

The purpose of this study was to test the hypothesis that even very small change of the cue direction in the treatment of the early osteonecrosis could affect the outcomes of operation. For this, the changes in stress transfer within the necrotic area of the femoral head were investigated under various directions and placements of the core utilizing finite element method. The loading of 3188N, which represents after-heel-strike, was imposed in cubic cosine pattern. All nodes on the most distal surface of the model were constrained in all directions. All materials included were assumed to have linear-elastic behavior. The result says that the critical stress, which causes collapse of the femoral head, was reduced when the core was oriented toward the posterior side of the femoral head regardless of location of the necrotic area. The same result was obtained either fibular bone grafting or cementation was adopted. As a consequence, the biomechanical study suggests that the core should be directed toward the loading point where the resultant force is applied to get more desirable treatment of the osteonecrosis of the femoral head in the early stage.

• Journal of Biomedical Engineering Research
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• v.36 no.4
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• pp.95-102
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• 2015

Epilepsy is a chronic neurological disease which produces repeated seizures. Over 30% of epileptic patients cannot be treated with anti-epileptic drugs, and surgical resection may cause loss of brain functions. Seizure suppression by electrical stimulation is currently being investigated as a new treatment method as clinical evidence has shown that electrical stimulation to brain could suppress seizure activity. In this paper, design of a real-time closed-loop neurostimulation system for epileptic seizure suppression is presented. The system records neural signals, detects seizures and delivers electrical stimulation. The system consists of a 6-channel electrode, front-end amplifiers, a data acquisition board by National Instruments, and a neurostimulator and Generic Osorio-Frei algorithm was applied for seizure detection. The algorithm was verified through simulation using electroencephalogram data, and the operation of whole system was verified through simulation and in- vivo test.

• Tunnel and Underground Space
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• v.25 no.3
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• pp.255-263
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• 2015

Explosive blasting is a very useful tool for mining and civil engineering applications. It, however, may cause severe environmental hazards on adjacent structures due to blasting impact. Blast engineers try to make optimum blast design to provide efficient performance and to minimize the environmental impact as well. It requires a pre-assessment of the impacts resulting from the blasting operation in design stage. One of the common procedures is to evaluate the proposed blast pattern through a series of test blasting in the field. Another approach is to evaluate the possible environmental effects using the numerical methods. There are a number of input parameters to be prepared for the numerical analysis. Some of them are well understood, while some are not. This paper presents some results of sensitivity analysis of the basic input parameters in numerical modelling of blasting problems so as to provide sound understanding of the parameters and some guidelines for input preparation.

• Progress in Superconductivity
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• v.13 no.1
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• pp.40-46
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• 2011

A superconductor flywheel energy storage system (SFES) is an electro-mechanical battery which transforms electrical energy into mechanical energy for storage, and vice versa. A 10 kWh class flywheel energy storage system (FESS) has been developed to evaluate the feasibility of a 35 kWh class SFES with a flywheel $I_p/I_t$ ratio larger than 1. The 10 kWh class FESS is composed of a main frame, a composite flywheel, active magnetic dampers (AMDs), a permanent magnet bearing, and a motor/generator. The flywheel of the FESS rotates at a very high speed to store energy, while being levitated by a permanent magnetic bearing and a pair of thrust AMDs. The 10 kWh class flywheel is mainly composed of a composite rotor assembly, where most of the energy is stored, two radial and two thrust AMD rotors, which dissipate vibration at critical speeds, a permanent magnet rotor, which supports most of the flywheel weight, a motor rotor, which spins the flywheel, and a central hollow shaft, where the parts are assembled and aligned to. The stators of each of the main components are assembled on to housings, which are assembled and aligned to the main frame. Many factors have been considered while designing each part of the flywheel, stator and frame. In this study, a 10 kWh class flywheel energy storage system has been designed and constructed for test operation.

• Journal of Trauma and Injury
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• v.25 no.4
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• pp.109-114
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• 2012

Purpose: Deep vein thrombosis and pulmonary thromboembolism are major causes of death after severe multiple trauma. Although various means of prevention have been presented and utilized, still, there are no standard guidelines for anticoagulation of multiple trauma because of some contraindications. Methods: A retrospective study of adult major trauma patients whose injury severity scores (ISSs) were over 16 and who had visited one university hospital in Daegu city was performed. We compared some features of patients diagnosed DVT or PTE with those of patients without DVT by computed tomography or ultra sonography. Those features included accompanying various kinds of intracranial hemorrhages, possibility of ambulation, emergent operation, early transfusion, and suspicious symptoms. Results: The mean age of the 58 subjects included in this study was $50.9{\pm}17.2years$, the mean ISS was $22.7{\pm}6.0$, and the mean hospital stay was $55.2{\pm}37.9days$. Ten(17.2%) patients had emergent surgery, and 44(75.9%) experienced delayed surgery. Early transfusion was needed in 34(58.6%) patients. Among the 18 patients diagnosed with DVT, accompanying intracranial hemorrhages were noted in 8(44.4%) patients; one of the 8 also had PTE. Among the same 18 patients, early transfusions were required in 11(61.1%) patients; one of the 11 also had PTE. Conclusion: The risk of DVT is increased in cases of severe multiple trauma, and many difficulties in applying anticoagulants are experienced. Though we need additional studies to decide proper prophylaxis for DVT and PTE, if the patient's general condition permits, a screening test for DVT as soon as possible could be an effective method to reduce the possibility of a bad outcome.