• Journal of the Korean Society for Nondestructive Testing
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• v.22 no.5
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• pp.490-499
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• 2002

Recently, gamma radiographic equipments have been used about 1,000 sets manually and operated by about 2,500 persons in Korea. In order for a radiography to work effectively with avoiding any hazard of the high level radiation from the source, many field workers have expected developing a wireless automatic remote exposure controller. The KlTCO research team has developed an automatic remote exposure controller that can regulate the speed of $0.4{\sim}1.2m/s$ by BLDC motor of 24V 200W which has output of $54kgf{\cdot}cm$, suitable torque and safety factor for the work. And the developed automatic remote exposure controller can control rpm of motor, pigtail position by photo-sensor and exposure time by timer to RF sensor. Thus, the developed equipment is expected that the unit can be used in many practical applications with benefits in economical advantage to combine the use of both automatic and manual type because attachment is possible existent manual remote exposure controller, AC and DC combined use.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.102-109
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• 2019

This paper describes the design of the circuit card assembly to eliminate the communication error on a servo control unit installed in the automated resupply vehicle K56. K56 is a weapon system that automates the supply and loading of ammunition on the K-55A1 self-propelled artillery. As the core item responsible for ammunition movement control, the servo control unit is required to have good communication stability and reliability, but the conventional unit has recognized a problem that communication error intermittently occurs, resulting in an emergency stop phenomenon. We analyzed the communication signal of the servo control unit and identified the failure cause of the circuit card assembly to solve this problem. In addition, the signal interference in data/address line of the circuit card assembly was confirmed through analysis of the failure cause, and redesigned to avoid the interference, such as adjustment of the distance between communication lines and position change. Finally, the proposed cause analysis and redesign were verified through the component of servo control unit and attachment test on K56. We expected these study results to be used as reference for the design of other similar items.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5534-5540
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• 2015

This In the railway signaling system, applications of axle counter in addition to track circuit goes on increasing for detecting train position. Consequently, this paper compares sensor methods of axle counter with between geo-magnetism method and proximity sensor method. And it presents differences and results, to improve reliabilities of train detection and axle counting. Also, this article presents an applied result which is based on field experience, with regard to installation, considering attachment condition of sensor part for accurate axle counting. This study acquires expandability that is able to perform not only axle counting function but also various other functions (direction detection of train, speed detection of train, and so on). It was a result of a change of design in order to judge phase difference of sensors, to improve reliability of axle counting. Furthermore, it does not subordinate to characteristics (type, weight of train). And it is confirmed that the omission of axle counting was not occurred in 350km/h. This was the result of Lab test after the construction of transfer equipment of trial axle and Test Bed for axle counting. Both of them are self-productions. Through this, it prepares foundation which is able to apply not only to train detection but also to speed of passing trains, formation number of trains, detector locking condition - when the train passes the section of switch point, and level crossing devices. Furthermore, it would be judged to contribute safety train operation if proximity sensor method applies to the whole railway signaling system from now on.

• Journal of Periodontal and Implant Science
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• v.36 no.1
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• pp.27-37
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• 2006

Although the main purpose of periodontal treatment to regenerate is the complete regeneration of periodontal tissue due to periodontal disease, most of the treatment cannot meet such purpose because healing by long epithelial junction. Therefore, diverse materials of resorbable and non-resorbable have been used to regenerate the periodontal tissue. Due to high risk of exposure and necessity of secondary surgical procedure when using non-resorbable membrane, guided tissue regeneration using the resorbable membrane has gain popularity, recently. However, present resorbable membrane has the disadvantage of not having sufficient time to regenerate date to the difference of resorption rate according to surgical site. Meanwhile, other than the structure stability and facile manipulation, acellular dermal matrix has been reported to be a possible scaffold for cellular proliferation due to rapid revascularization and favorable physical properties for cellular attachment and proliferation. The purpose of this study is to estimate the influence of acellular dermal matrix on periodontal ligament, cementum and alveolar bone when acellular dermal matrix is implanted to 1-wall alveolar bone defect. 4 dogs of 12 to 16 month old irrelevant to sex , which below 15Kg of body weight, has been used in this study. ADM has been used for the material of guided tissue regeneration. The 3rd premolar of the lower jaw was extracted bilaterally and awaited for self-healing. subsequently buccal and lingual flap was elevated to form one wall intrabony defect with the depth and width of 4mm on the distal surface of 2nd premolar and the mesial surface of 4th premolar. After the removal of periodontal ligament by root planing. notch was formed on the basal position. Following the root surface treatment, while the control group had the flap sutured without any treatment on surgically induced intrabony defect. Following the root surface treatment, the flap of intrabony defect was sutured with the ADM inserted while the control group sutured without any insertion. The histologic specimen was observed after 4 and 8 weeks of treatment. The control group was partially regenerated by periodontal ligament, new cementum and new alveolar bone. the level of regeneration is not reached on the previous formed notch. but, experimental group was fully regenerated by functionally oriented periodontal ligament fiber. new cementum and new alveolar bone. In conclusion, we think that ADM seems to be used by scaffold for periodontal ligament cells and the matrix is expected to use on guided tissue regeneration.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.665-670
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• 2004

The mandibular buccal frenum becomes a problem when its attachment is too close to the marginal gingival. Heavy buccal frenum mucogingivally results in insufficient attached gingiva, inadequate vestibular depth and also difficulty in eruption of mandibular premolar. The aim of this study is to demonstrate the effectiveness of apically positioned partial-thickness flap as adequate method in order to remove heavy buccal frenum and expose impacted teeth. The author presents the case of a 12-year-old boy. He had problems that was prolonged eruption of #34, #35 due to high pull buccal frenum. After space regaining for normal eruption of #34, #35, we performed apically positioned partial-thickness flap on #34, 35 area. As a results, we confirmed that eruption of #34, #35 has been processed normally And vestibular depth, position of buccal frenum and width of attached gingival was within a normal range. Decrease in muscle pull, adequate width of attached gingiva and increased vestibular depth can be expected from this treatment.

• Therapeutic Science for Rehabilitation
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• v.8 no.4
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• pp.7-18
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• 2019

Objective : This systematic review aimed to investigate the impact of transcranial direct current stimulation combined with constraint-induced movement therapy (CIMT) in patients with stroke Methods : PubMed and NDSL databases were employed to review literature published between January 2009 and December 2018. The main search terms were "Transcranial direct current stimulation" or "tDCS," "Constraint-induced movement therapy" or "CIMT," "Upper extremity function," "Upper limb," and "Stroke." Based on the inclusion and exclusion criteria, 6 articles were selected. Furthermore, intervention effects on upper extremity function, activities of daily living, and cortical activity were assessed. Results : The current intensity, application time, and protocol of the CIMT varied the between studies. However, the intervention procedures to perform CIMT immediately after transcranial direct current stimulation was the same. Transcranial direct current stimulation combined with CIMT was effective in improving upper limb function and activities of daily living in patients with stoke and had a significant effect on cerebral cortex activation. Conclusions : This study provides information on transcranial direct current stimulation combined with CIMT for use by clinical therapists. Further studies are needed to standardize the stimulation time, current intensity, and electrode attachment position. Furthermore, randomized controlled trials, including long-term follow up, are needed for larger populations using the most appropriate CIMT protocol.

• Journal of the Korea Institute of Construction Safety
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• v.1 no.1
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• pp.47-56
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• 2018

In this paper, we analyze various cases of accidents caused by vehicle-mounted MEWPs(mobile elevated work platforms) which are most widely used for the high position level works, review the safety improvement measures for each of them, and propose basic data for the revision of related laws. The accidents by MEWPs were caused by the high level of works, which lead to fatal personnel accidents, so the measures for safety must be thoroughly carried out and the obligatory regulations by the related laws must be strictly observed. In this paper, we classify the cases of accidents at the workshop as 4 representative types and propose measures and remedies for them. According to the current regulations, it is possible to prepare for the accidents such as the wire rope breakage by switching to the all-chain drive method which does not have a daily use time limit instead of the wire rope drive method which is widely used at present. Also, it is suggested to add the daily use timetable to the nameplate attachment duty item according to the driving class.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.980-991
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• 2023

To prevent accidents near the quay caused by a ship, ports are generally designed and constructed through navigation and berthing safety assessment. However, unpredictable accidents such as ship collisions with the quay or personal accidents caused by ropes still occur sometimes during the ship berthing or mooring process. Automatic mooring systems, which are equipped with an attachment mechanism composed of robotic manipulators and vacuum pads, are designed for rapid and safe mooring of ships. This paper deals with a displacement and velocity measurement system for the automatic mooring device, which is essential for the position and speed control of the vacuum pads. To design a suitable system for an automatic mooring device, we first analyze the sensor's performance and outdoor environmental characteristics. Based on the analysis results, we describe the configuration and design methods of a displacement and velocity measurement system for application in outdoor environments. Additionally, several algorithms for detecting the sensor's state and estimating a ship's velocity are developed. The proposed method is verified through some experiments for displacement and speed measurement targeted at a moving object with constant speed.

• Journal of Aerospace System Engineering
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• v.18 no.1
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• pp.37-45
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• 2024

This paper presents a design approach for passive vibration control to reduce vertical vibrations transmitted to the control unit during hovering flight of a quadrotor drone. Ground vibration test simulation based on finite element model was performed for forced vibration analysis of the quadrotor drone. First, modal analysis was performed to evaluate dynamic characteristics. Forced vibration response analysis was then performed to obtain the steady-state response within the operating frequency range under the hovering flight condition. Furthermore, to obtain the vibration reduction effect, a viscous damping tape was applied at positions that could induce vibrations transmitted to the control unit under the same conditions. Such a passive vibration control approach was investigated. Relevant vibration reduction effect was assessed with respect to the application of damping materials and the attachment position.

• Journal of Korean Academy of Nursing
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• v.13 no.2
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• pp.22-43
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• 1983

1. Need for and Purpose of the Study. There is an increasing demand for curriculum improvement of the Korean Army Nursing Academy (KANA), since it was upgraded into 4-year institution of higher learning from 3-year one. In particular, it is strongly advocated that the KANA needs the outside expertise for its curriculum improvement-namely not only from the internal military view of points but also from the viewpoints of professional educational society, In line with such a necessity for the study, this study was aimed at 1) analyzing the current actual practices of KANA'S curriculum, 2) investigating the desired practices of KANA'S curriculum, and 3) identifying the discrepancy between the actual and desired practices of curriculum. 2. Problems for the Study This study had 4 problems to be answeared as follows: 1) What are the actual curriculum practices of KANA? 2) What are the desired curriculum practices of KANA? 3) How are the extents of perception of actual and desired curriculum different in four groups (student, faculty & administrator, nurse, and medical doctor in militay hospital) ? 4) What are the restraining forces that impede the change from actual to desired curriculum practices? 5) What are the relationships of curriculum component,』 in actual and desired curriculum practices? 3. Methods and Procedures This study was conducted by means of document analysis in addition to literature review and by means of needs assessment questionnaire which was developed by the researcher. The questionnaire included 62 statments with 7 questions for demographic data collection. The needs assessment questionnaire was managed to a total of 243 subjects (100 students, 46 faculty & administrators, 55 nurses, and 42 medical doctors), The collected data were treated using SPSS computer system so as to calculate mean scores, standard deviations, and correlation coefficients. The significance test was made through t-test and one-way ANOVA. The statistical significance level was set at both .05 and .01 level. 4. Major findings The major findings in this study are as follows: 1) The score of desired practices was significantly greater than that of actual practices, representing a strong need for curriculum betterment. 2) There were significant differences in the perceptions of actual practices as well as desired practices among four groups (student, faculty & administrater, nurse, and medical doctor). 3) The most frequently selected restraining forces were army's inherent character, economical limitation, and educational expertise limitations. 4) Such variables as sex, position attachment to the KANA and grade made a statistically significant effect on the perception of desired curriculum practice, while the variables like marrige, position, and military class made it on the perception of actual curriculum practice. 5) The coefficients among the curriculum components were lower in perception of the actual curriculum practices than those in the desired practices. 5. Conclusions The conclusions based on the major findings of this study are as follows: 1) The current curriculum development procedure of the KANA is not consistent with the theoretical frame of systematic development sarategy of curriculum. 2) There are wide conflicts among the groups who are supposed to participate in curriculnm development, concerning the actual and desired practices of KANN'S curriculum. 3) A great deal of need for curriculum improvement for the KANA is clearly felt, and in particular, in the process of teaching and learning. 4) Each component of curriculum is not intergrated into a whole development procedure, being segregated each other. 5) For better curriculum improvement, such restraining forces as financial and professional limitations should be eliminated. 6. Recommendations 1) For Further Research a. There is a need to replicate this study after in-depth statistical analysis of each item of need assessment questionnaire, and with more representative subjects. b. A study should be conducted which. has its focus on the analysis of restraining forces for the change from actual to desired curriculum practices of the KANA. 2) For KANA'S Curriculum Improvement a. There is a need to promote the professional expertise of the participants in curriculum development and the communication among them. b. It is desirable to establish an institution or section of administration, which is soley in charge of curriculum development. c. To better develop KANA's curriculum not only faculty and administrators but also students should be encouraged to participate in development process, while the military medical doctors' participation should be carefully considered.