• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.2
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• pp.82-90
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• 2024

It often happens that a removable partial denture needs to be repaired due to tissue changes in the remaining alveolar ridge, fracture of the denture, or fracture of the abutment tooth. There are several advantages to retrofitting a customized surveyed crown under the existing RPD. Retrofitting a crown to the RPD decreases the economic burden to the patient and avoids the need for several appointments to fabricate a new RPD. It is difficult for artificial teeth used to repair dentures due to fractured natural teeth to have a shape similar to that of natural teeth, and to repair aesthetic artificial teeth, it is necessary to manufacture customized artificial teeth similar to the shape of each patient's teeth. Recently, CAD/CAM technology has been used to fabricate customized prosthetics on existing RPD to achieve high retention and fitness accuracy, and by manufacturing customized artificial teeth, more aesthetic and harmonious artificial tooth repair is possible. This is a case in which a denture was repaired using a digital method to fabricate a customized prosthesis on an existing partial denture and customized artificial teeth that mirrored the adjacent dentition, saving time and cost, simplifying the process, and achieving aesthetically and functionally satisfactory results.

• Journal of Preventive Medicine and Public Health
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• v.27 no.3 s.47
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• pp.447-463
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• 1994

Despite the public health importance of injury and poisoning in terms of its high mortality and incidence, epidemiologic information to be utilized are scarce in Korea. This study was carried out in 1990 on a representative sample population (about 55,000 persons) along with the 6th National Tuberculosis Prevalence Survey in order to estimate the magnitude of injury and poisoning occurrence and to identify its epidemiologic characteristics which can be aided for establishing preventive strategy. Pre-tested and structured Questionnaire was used by trained interviewer to collect data including general information of the person, various information on the injury and poisoning during the past one year such as time and place of its occurrence, its nature and external causes, type of medical institute attended, duration of treatment and outcome of the accident occured. In analysis of the data collected incidence rates per 1000 persons by sex, age group and its nature as well as external causes, and relative frequencies were calculated. The result obtained are as followings; 1. The incidence rate per 1000 was 30 for both sexes, 39 for male and 22 for female, male being 1.8 times more frequent than female. Age adjusted incidences were not much different from the crude rates. Age group specific rate curve showed bimodal shape in both sexes, small peaks in preschool children and higher peaks in older ages. The incidence rate per 1000 people by area was highest in Jeon-bug province (57/1000) and the lowest in Daegu city(11/1000). 2. The place where the injuries occured were road in 46%, within the boundary of house in 25%, and working place in 12% The injuries and poisoning had occured more frequently during the months from March to August of the year than other months. 3. The relatively frequent injuries by its nature were contusion with intact skin surface (19%), fracture of upper limb (13%), open wound of head, neck and trunk (12%) and fracture of lower limb (11%) among males; contusion with intact skin surface (28%), sprains and strains of joints and adjacent muscle (14%), fracture of upper limb (10%) and fracture of lower limb (9%) among females. Higher incidence rate among males than females were fracture of skull (4.5 times), open wound and fractures of limbs ($2{\sim}3$ times). Age specific rate of injuries and poisoning by its nature showed increasing pattern by age in fractures of upper and lower limbs and sprains & strains of joints whereas the age group of 30's showed highest incidence in open wounds of upper limb. Fractures of radius and ulna in upper limb, fractures of tibia & fibula and ankle in lower limb were most frequent among fractures of upper and lower limbs. The frequent injuries among sprains and strains of joints and adjacent muscles were that of ankle, foot and back, and among open wound were that of head and fingers. 4. Relative frequency of injuries and poisoning by external causes showed following order : other accidents (25%), accidental falls (23%), motor vehicle accident (22%) and other road vehicle accident (14%) among males and accidental falls (37%), motor vehicle accident (24%) and other accident (18%) among females. The external causes revealing higher incidences among males than females, were other road vehicle accident (4.8 times), vehicle accident not elsewhere classifiable (4.4 times), accidental poisoning (4.4 times), accidents due to natural and environmental factors (2.8 times), and sucide & self-inflicted injuries (2.8 times). Age specific incidence by external causes for frequent injuries showed that incidence of other accident steadily increased from 10's till age 50's; motor vehicle traffic accident increased from age 20's and dropped after age 60's; on the other hand accidental fall increased strikingly by age. The most frequent external causes among motor vehicle traffic accidents was motor vehicle traffic accident involving collision with pedstrain (69%), pedal cycle accident (30%) and other road vehicle accident (71%) among other road vehicle accidents; falls on same level from slipping, tripping or standing (44%) and other falls from one level to another among accidental falls; accidents caused by machinary (32%) for male and striking against or struck accidentally by objects or person for female among other accidents. 5. Seventy nine percent of the injuries and poisonings were treated in general hospital or hospital/clinic. The duration of treatment ranged from a few days to 123 weeks; the majority(52%) took under 2 weeks, 36% for $3{\sim}8$ weeks and 4% over 21 weeks. 6. The accident resulted in full recovery of normal healthy state in 62%, residual functional defects in 21% and on process of treatment in 16%.

• Journal of Trauma and Injury
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• v.24 no.2
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• pp.129-135
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• 2011

Purpose: During August 2010, a natural gas fuel cylinder on a bus exploded in downtown Seoul, injuring 20 citizens. This kind of blast injury has never been reported in Korea before. Thus, the goal of this study was to review the clinical features of these victims to help physicians manage similar cases and to understand the risk factors associated with blast injuries in everyday life. Methods: Twenty (20) victims who visited nearby emergency departments, and 3 peoples left hospital without care. Seventeen (17) victims were included in this study, and the following factors were investigated: age, sex, type of hospital, diagnosis of injury, injury mechanism, position of victim (in-bus/out of bus), classification of injury severity with START (simple triage and rapid treatment), and classification of injury according to the mechanism of the blast injury. Results: The victims included 8 males (47%), 9 females (53%). The mean age was $37.5{\pm}12$. Thirteen (13) victims were transferred to two tertiary hospitals, and 4 were transferred to two secondary hospitals. The types of injury were 3 fractures, 2 ligaments injuries, 6 contusions, 4 abrasions, and 3 open wounds (one of them was combined fracture). According to START classification, 17 victims were 1 immediate, 11 minor, 5 delayed, and no death. Classifications according to the mechanism of the blast injury were 1 primary injury, 6 secondary injuries (2 of them combined other mechanism), 3 tertiary injuries and 9 quaternary injuries. Conclusion: Trauma care physicians should be familiar with not only the specific types of injuries from blast accidents, but also the potential accidents that may occur in public facilities.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.4
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• pp.439-445
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• 2011

Forensic Engineering is the art and science of professionals qualified to serve as engineering experts in courts of law or in arbitration proceedings. Buses using compressed natural gas (CNG) trend to be extended in use internationally as optimal counterplan for reducing discharge gas of light oil due to high concern about environment. However, CNG buses have to be equipped with composite pressure vessels (CPVs); since the CPVs contain compressed natural gas, the risks in the case of accident is very high. Hence, the investigation of such accidents is usually associated with engineering analysis. Among the possible reasons for such CNG explosion accidents is vehicle fire and vessel fracture. By conducting formal inspection and engineering tests, in this study, the cause of vessel explosion is investigated by analyzing the failure mechanism by fractography and by comparing the material properties of a reference part with those of a problem part by adopting instrumented indentation technique.

• The Journal of Natural Sciences
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• v.8 no.1
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• pp.53-59
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• 1995

Effects of sintering additives and sintering temperatures on the sintering behavior and mechanical properties of SiC whisker reinforced alumina composites have been investigated in this study. Dense (>95% TD) composites were obtained by using 2 wt% $Y_2O_3$ as liquid phase sintering additive. But only porous composite could be obtained when the sintering additives were MgO and $TiO_2$, which were known as the sintering additives for solid state sintering of alumina. Bending strength and fracture toughness were enhanced by reinforcement of SiC whisker. It is belived from the microstructure investigation that the enhanced by strength and toughness could be attribute to the reinforcing and grain growth inhibition effects of SiC whisker. After HIP treatment, fully dense composites were obtained and further enhanced mechanical properties achieved.

• Journal of the Mineralogical Society of Korea
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• v.32 no.4
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• pp.259-271
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• 2019

We evaluated mineralogical, physical property and accelerated weather resistance of cinnabar, realgar and orpiment used as cultural heritages and traditional paintings. JB and JS are sample names of cinnabar and JH and UH are sample names of orpiment and Realgar, respectively. As a result of mineralogical property evaluation, Jinsa was identified cinnabar (HgS) and there was no difference in chemical composition according to the grade. UH and JH were confirmed realgar (AsS) and orpiment (As₂S₃), respectively. The polarization characteristics such as shape and color indicate that pigments using our test were natural mineral pigment observed by polarization microscope. Especially, in the case of cinnabar, it is not easy to distinguish between natural mineral pigment and synthetic pigment. But the results of polarization microscope said that cinnabar is natural occurring mineral which have authentic mineral particle and unevenly fracture. As a result of thermal analysis, JH has a higher glass transition temperature and heat stability than UH. After accelerated weather test, cinnabar, realgar and orpiment were striking result in color change because of light degradation. Red color of cinnabar turn into black and the color of realgar and orpiment became brighter than before. JB (meta-cinnabar) is more photosensitivity and faster becoming dark than JB (cinnabar). Finally light transforms realgar (red, As₄S₄) in arsenolite (As₂O₃).

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.4
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• pp.21-28
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• 2014

In this study, evaluated ware the strength and durability of the vegetated water purification channel concrete to which recycled aggregates, hawang-toh and jute were applied. Box-Behnken method of response surface analysis in statistics was applied to the experimental design. Experimental variables are as follows, recycled coarse aggregates, hawang-toh, blast-furnace slag and jute fiber. In the experiment, conducted were the tests of compressive strength, chloride ion penetration, abrasion resistance and impact resistance the replacement rate effects of the recycled aggregates, blast-furnace slag and hwang-toh on the performance of vegetated water purification channel concrete were analyzed by using the response surface analysis method on the basis of the experimental results. In addition, an optimum mixing ratio of vegetated water purification channel concrete was determined by using the experimental results. The optimum mixing ratio was determined to be in 10.0% recycled coarse aggregates, 60.0% blast-furnace slag, 10.1% hwang-toh and 0.16% jute fiber. The compressive strength, chloride ion penetration, abrasion rate, and impact number of fracture test results of the optimum mixing ratio were 24.1 MPa, 999 coulombs, 10.30 g/mm3, and 20 number, respectively.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.3
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• pp.21-27
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• 2016

This study was performed to evaluate engineering properties of carbon and glass fiber reinforced recycled polymer concrete. Fiber reinforced recycled polymer concrete were used recycled aggregate as coarse aggregate, natural aggregate as fine aggregate, $CaCO_3$ as filler, unsaturated polyester resin as binder, and carbon and glass fiber as fibers. The compressive and flexural strength of carbon fiber reinforced recycled polymer concrete were in the range of 68~81.5 MPa and 19.1~21.5 MPa at the curing 7days. Also, the compressive and flexural strength of glass fiber reinforced recycled polymer concrete were in the range of 69.4~85.1 MPa and 19~20.1 MPa at the curing 7days. Abrasion ratio of carbon and glass fiber reinforced recycled polymer concrete were decreased 21.6 % and 11.6 % by fiber content 0.9 %, respectively. After impact resistance test, drop numbers of initial and final fracture were increased with increase of fiber contents. Accordingly, carbon fiber and glass fiber reinforced recycled polymer concrete will greatly improve the hydraulic structures, underground utilities and agricultural structures.

• Journal of Ocean Engineering and Technology
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• v.33 no.6
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• pp.547-555
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• 2019

The purpose of this study was to establish a numerical model of polyurethane foam (PUF) to simulate the dynamic response and strength of membrane-type Liquefied natural gas (LNG) Cargo containment system (CCS) under the impact load. To do this, initially, the visco-plastic behavior of PUF was characterized by testing the response of the PUF to the impact loads with various strain rates as well as PUF densities at room temperature and at cryogenic conditions. A PUF material model was established using the test results of the material and the FE analysis. To verify the validation of the established material model, simulations were performed for experimental applications, e.g., the dry drop test, and the results of FEA were compared to the experimental results. Based on this comparison, it was found that the dynamic response of PUF in dry drop tests, such as the reaction force and fracture behaviors, could be simulated successfully by the material model proposed in this study.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.21 no.2
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• pp.63-71
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• 2015

Background: The purpose of the study, using the ICF Tool in the process of rehabilitation of artificial joint replacement surgery of the hip joint, goal setting and understanding of the problem, through the process of creating intervention strategies, useful clinical practical course for rehabilitation I try to present the data. Methods: Fracture was the left total hip replacement (THR) surgery due to women of 76 years old. I proceed in order screening, evaluation, diagnosis, prognosis, treatment planning and intervention, re-screening. Needs of the patient was walking short distances for using the toilet. In order to improve was carried out arbitration, after you have created a list of issues that limit the ability to walk short distances. Results: It was revealed improved results in self-paced walk test (SPWT) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to examine whether the goals. In addition, MMT VAS, DGI, and TUG is a detailed goal was improved. Conclusions: It can be shown objectively the results of interventions performed for the purpose of solving the problem which is grasped through clinical Practical course for short-range walking ability enhance patient THR. I considered practical clinical course using the ICF Tool would be useful.