• The Journal of Korean Academy of Prosthodontics
• /
• v.54 no.3
• /
• pp.226-233
• /
• 2016

Purpose: The purpose of this study was to evaluate the adaptation of lithium disilicate crowns fabricated by CAD-CAM (computer aided design-computer aided manufacturing) and heat-press technique to compare two different measurement methods in assessing fit of the ceramic crowns: micro CT and cross-section technique. Materials and methods: A prepared typodont mandibular molar for ceramic crown was duplicated and ten dies were produced by milling the PMMA (polymethylmethacrylate) resin. Ten vinyl polysiloxane impressions were made and stone casts were produced. Five dies were used for IPS e.max Press crowns with heat-press technique. The other five dies were used for IPS e.max CAD crowns with CAD-CAM technique. Ten lithium disilicate crowns were cemented on the resin dies using zinc phosphate cement with finger pressure. The marginal and internal fits in central buccolingual plane were evaluated using a micro CT. Then the specimens were embedded and cross-sectioned and the marginal and internal fits were measured using scanning electronic microscope. The two measurement methods and two manufacturing methods were compared using Mann-Whitney U test (SPSS 22.0). Results: The marginal and internal fit values using micro CT and cross-section technique were similar, showing no significant differences. There were no significant differences in adaptation between lithium disilicate crowns fabricated with CAD-CAM and heat-press technique. Conclusion: Both micro CT and cross-section technique were acceptable methods in the evaluation of marginal and internal fit of lithium disilicate crown. There was no difference in adaptation between lithium disilicate crowns fabricated with CAD-CAM and heat-press technique except occlusal fit.

• Economic and Environmental Geology
• /
• v.44 no.1
• /
• pp.83-94
• /
• 2011

Extra heavy oil reservoirs are distributed over the world but most of them is deposited in the northern part of the Orinoco River in Venezuela, in the area of 5,500 $km^2$, This region, which has been commonly called "the Orinoco Oil Belt", contains estimated 1.3 trillion barrels of original oil-in-place and 250 billion barrels of established reserves. The Venezuela extra heavy oil has an API gravity of less than 10 degree and in situ viscosity of 5,000 cP at reservoir condition. Although the presence of extra heavy oil in the Orinoco Oil Belt has been initially reported in the 1930's, the commercial development using in situ cold production started in the 1990's. The Orinoco heavy oil deposits are clustered into 4 development areas, Boyaco, Junin, Ayachoco, and Carabobo respectively, and they are subdivided into totally 31 production blocks. Nowadays, PDVSA (Petr$\'{o}$leos de Venzuela, S.A.) makes a development of each production block with the international oil companies from more than 20 countries forming a international joint-venture company. The Eastern Venezuela Basin, the Orinoco Oil Belt is included in, is one of the major oil-bearing sedimentary basins in Venezuela and is first formed as a passive margin basin by the Jurassic tectonic plate motion. The major source rock of heavy oil is the late Cretaceous calcareous shale in the central Eastern Venezuela Basin. Hydrocarbon materials migrated an average of 150 km up dip to the southern margin of the basin. During the migration, lighter fractions in the hydrocarbon were removed by biodegradation and the oil changed into heavy and/or extra heavy oil. Miocene Oficina Formation, the main extra heavy oil reservoir, is the unconsolidated sand and shale alternation formed in fluvial-estuarine environment and also has irregularly a large number of the Cenozoic faults induced by basin subsidence and tectonics. Because Oficina Formation has not only complex lithology distribution but also irregular geology structure, geological evolution and characteristics of the reservoirs have to be determined for economical production well design and effective oil recovery. This study introduces geological formation and evolution of the Venezuela extra heavy oil reservoirs and suggest their significant geological characteristics which are (1) thickness and geometry of reservoir pay sands, (2) continuity and thickness of mud beds, (3) geometry of faults, (4) depth and geothermal character of reservoir, (5) in-situ stress field of reservoir, and (6) chemical composition of extra heavy oil. Newly developed exploration techniques, such as 3-D seismic survey and LWD (logging while drilling), can be expected as powerful methods to recognize the geological reservoir characteristics in the Orinoco Oil Belt.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.8 no.2
• /
• pp.109-114
• /
• 2009

Purpose: The purpose of this study is to compare the clinical results of ACL reconstruction between two groups using hamstring tendon autograft and tibialis anterior tendon allograft. Materials and Methods: Between January 2006 and June 2007, we analyzed 68 cases of ACL reconstruction, 32 cases using hamstring tendon autograft and 36 cases using tibialis anterior tendon allograft, with a minimum follow-up of 24 months. For the clinical evaluation, we evaluated the Lysholm score, anterior laxity by Telos device and KT-2000 arthrometer. Results: The mean diameter of graft were 8.0 mm (7.0~9.0 mm) in autograft group and 9.1 mm (8.0~10.0 mm) in allograft group. In all cases, the range of motion was above 135 degrees. The average side to side difference in Telos stress test decreased from $7.3{\pm}1.0$ mm to $2.4{\pm}1.1$ mm in autograft group and from $7.4{\pm}1.2$ mm to $2.3{\pm}1.3$ mm in allograft group. The average Lysholm knee score improved from $72.6{\pm}3.4$ to $92.3{\pm}3.5$ in autograft group and from $72.3{\pm}3.5$ to $91.6{\pm}3.3$ in allograft group. There was no significant difference between two groups in clinical results. Conclusion: Both hamstring tendon autograft and tibialis anterior tendon allograft groups showed satisfactory clinical results, with no significant difference in outcomes between the groups. We suggest that both hamstring tendon autograft and tibialis anterior tendon allograft will be considered as acceptable graft for anterior cruciate ligament reconstruction.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.17 no.5
• /
• pp.1-13
• /
• 2018

Divers types of Personal Mobility(PM) are appeared on the market after the Segway is introduced. PMs have propagated very rapidly with their ease of use, and accidents related with PM show a sudden increase. Many studies on the PM are performed as its trend, but dring safety of passengers are excluded. In this study, criteria which can be adopted for PM's driving safety evaluation are reviewed. Also result of driving safety evaluation on 3 types of PM(wheel chair, kickboard, scooter(seating/standing) and walking using deducted criteria is given. COG(Center of the gravity) and SM(Stability Metric) are finally selected two criteria among many of them used in other fields. COG indicates how the center of mass deviates from the direction of the gravity. SM is a normalized value of generated force when PM moves as internal force, angular momentum, and ground reaction force. 0 means stop, and negative value means rollover, so it can be used for safety evaluation of PM. Average and standard deviation of measurement are standard of safety on the COG analysis. Wheel chair is the most safe and kickboard is the most unstable on the COG analysis. Wheel chair is also ranked as top safe on the SM analysis. Among two riding types(seating and standing) on the scooter, seating type is evaluated more safer than standing type. It is proposed that more various type of PMs are need to get safety evaluation for drivers and devices themselves together.

• Journal of the Korean earth science society
• /
• v.33 no.4
• /
• pp.360-375
• /
• 2012

The purpose of this study was to compare 10th grade students' understanding of concepts about the plates' motions depending on the different spatial ability. Based on previous studies and literature reviews, two instruments were selected and used in this study. The Spatial Perception Test developed in Korean Testing Center was applied to measure students' spatial ability. Another instrument for testing students' understandings of plates' motions consists of a total of 10 items. The instruments were distributed to 118 students who were 10th graders in metropolitan city. The results are as follows: First, a correlation coefficient between conceptual understanding of plates' motions and spatial ability was r=0.439 (p<.01). It indicates that conceptual plates' motions and spatial ability have a moderate relationship. The students were divided into two groups (high and low) by spatial ability. The independent t-test was performed and reveals that the statistically significant difference between high and low groups. On the other hand, the 6 students (3 higher spatial ability students and 3 lowers) were selected and interviewed individually to find the differences in their understanding of the concept of plates' motions. The findings from interviews indicate that most students recognized about concepts of trench and ocean ridge, a rise and drop of the mantle, and divergent and convergent boundaries. However, students had misconceptions about section of trench and ocean ridge. In addition, the students who had higher spatial ability knew the more proper concepts about the creation and extinction of plate, crustal movements, and bottom of the ocean extension, whereas the students who had the lower spatial ability had misconceptions.

• Economic and Environmental Geology
• /
• v.39 no.2 s.177
• /
• pp.129-149
• /
• 2006

Previously published stratigraphic, sedimentologic, paleontologic, paleomagnetic and geophysical data are reviewed to make an understanding on the tectonic evolution of the Cretaceous Gyeongsang (Kyongsang) basin, southeast Korea. A stratigraphic framework and a tectonic model on the formation and deformation of the Gyeongsang Basin are newly proposed on the basis of integration these data with magmatism and mineralization ages in the basin. A newly proposed stratigraphic framework indicates that strata in the basin can be subdivided into five distinct stratigraphic units that represent pre-rifting, syn-rifting, inversion I, II, and III stages. The Gyeongsang Basin was formed initially as a pre-rifting stage due to north-south extension in the Late Jurassic prior to a syn-riftins stage that resulted from east-west extension during the Early Cretaceous. In the Late Cretaceous, the basin was deformed by three-staged sequential deformation of north-south, northwest-southeast, and east-west compressions. The tectonic history of the basin has been largely controlled by the change of motion of the Izanagi Plate from north to northwest during the Cretaceous. In the early Cretaceous, the Izanagi Plate began to subduct northward beneath the Eurasian Plate and caused the left-lateral strike-slip fault systems in the southern part of the peninsula. The left-lateral wrenching of these fault systems was causally linked to development of pull-apart basins, such as the Gyeongsang Basin in the southeastern part of the peninsula. However, northwestward movement of the Izanagi Plate during the Late Cretaceous probably led to the extensive volcanism as well as sequential deformations in the basin. The stratigraphic and tectonic model, which is newly proposed as a result of this study, may be expected to enhancing the efficiency for exploration and exploitation of useful mineral resources in the basin as well as establishing geologic history in the Cretaceous Gyeongsang Basin. Together with the spatial and temporal correlation of the Cretaceous basins in adjacent areas, this stratigraphic and tectonic model provides a new geologic paradigm to delineate the sophisticated tectonic history of East Asia turing the Cretaceous.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.15 no.1
• /
• pp.90-93
• /
• 2011

Purpose: A Pixelated BSGI gamma camera has features to enhance resolution and sensitivity and minimize the distance between detector and organs by narrow FOV. Therefore, it is known as useful device to examine small organs such as thyroid, parathyroid and gall bladder. In general, when we would like to enlarge the size of images and obtain high resolution images by gamma camera in nuclear medicine study, we use pinhole collimator. The purpose of this study is to evaluate the usefulness of Pixelated BSGI gamma camera and to compare to it using pinhole collimator in thyroid scan which is a study of typical small organs. Materials and methods: (1) The evaluation of sensitivity and spatial resolution: We measured sensitivity and spatial resolution of Pixelated BSGI with LEHR collimator and Infinia gamma camera with pinhole collimator. The sensitivity was measured by point source sensitivity test recommended by IAEA. We acquired images considering dead time in BSGI gamma camera for 100 seconds and used $^{99m}TcO4-\;400{\mu}Ci$ line source. (2) The evaluation of thyroid phantom: The thyroid phantom was filled with $^{99m}TcO4-$. After set 300 sec or 100 kcts stop conditions, we acquired images from both pixelated BSGI gamma camera and Infinia gamma camera with LEHR collimator. And we performed all thyroid studies in the same way as current AMC's procedure. Results: (1) the result of sensitivity: As a result, the sensitivity and spatial resolution of pixelated BSGI gamma camera were better than Infinia's. The sensitivities of pixelated BSGI and Infinia gamma camera were $290cps/{\mu}Ci$ and $350cps/{\mu}Ci$ respectively. So, the sensitivity of pixelated BSGI was 1.2 times higher than Infinia's (2) the result of thyroid phantom: Consequently, we confirmed that images of Pixelated BSGI gamma camera were more distinguishable between hot and cold spot compared with Infinia gamma camera. Conclusion: A pixelated BSGI gamma camera is able to shorten the acquisition time. Furthermore, the patients are exposed to radiation less than before by reducing amount of radiopharmaceutical doses. Shortening scan time makes images better by minimizing patient's breath and motion. And also, the distance between organ and detector is minimized because detector of pixelated BSGI gamma camera is small and possible to rotate. When patient cannot move at all, it is useful since device is feasible to move itself. However, although a pixelated BSGI gamma camera has these advantages, the effect of dead time occurs over 2000 cts/s since it was produced only for breast scan. So, there were low concentrations in organ. Therefore, we should consider that it needs to take tests to adjust acquisition time and amount of radiopharmaceutical doses in thyroid scan case with a pixelated BSGI gamma camera.

• The Korean Journal of Pain
• /
• v.1 no.1
• /
• pp.106-119
• /
• 1988

For the relief of pain in 3 cases of whiplash syndromes (case I, II and IV) and in one of reflex sympathetic dystrophy (case III), we have carried out six intentional. total spinal blocks (TSB) which attempted two times in case I, three in case II and one in carte III whoso various symptoms were chronically unresponsive to the usual conservative treatments, and a time of cervical epidural and right suprascapular nerve block in case W whose acute symptom lasted 4 drys following the cervical injury (see fables from 1 to 9). During the 753, we have observed clinically the sequential charges of respiration, lid and pupil reflexes, body motion and consciousness. And checked the blood pressure, pulse rate and arterial Pco2. The effectiveness of those blocks has been assessed by using the Visual Analog Scale which is designed to measure the patient$\acute{s}$ subjective intensity of pain and also we have found out the sequelae following those blocks. The methods of the blocks were as the following: 1. Under the N.P.O. for 8~10 hours, the preparations of immediate cardiopulmonary resuscitation and premedication with atropine 0.5mg at thirty minutes before the TSB, it was performed by injecting the mixture of 2% mepivacaine 10 or 15ml and normal saline 10 or 5ml through No. 23 G. spinal needle into the subarachnoid space of $C_7-T_1$ interspinous region with fully flexed neck on the lateral posture. Immediately after the injection of the local anesthetic in the lateral position, the patient$\acute{s}$ were hasten to change Trendelenburg$\acute{s}$ position in order to act the drugs cephalad and to make easy controlled respiration with oxygen. 2. The cervical epidural block was done by injecting the mixture of 0.5% bupivacaine 4ml, normal saline 4ml and triamcinolone 15mg through No. 18 G. Tuohy needle into the epidural space on the same region and posture as the above without premedication.7he suprascapular nerve block was done by injecting of 0.5% bupivacaine 3ml only into the right suprascapular fossa on the sitting posture. The results were as the following: 1. The cessation of respiration was seen within 5 minutes following the subarachnoidal injection of the above 20ml mixture in 2 to 3 minutes and then soon the consciousness began to disappear. The loss of Lid and pupil reflexes noted between 5 to 10 minutes and the size of the dilated pupils was equal between 5 to 20 minutes, but the pupil of the dependent side on tile lateral position was dilated 1 to 3 minutes earlier than that of the independent. The patients had r=ever responded to any stimulations during the TSB except their heart funtion. 2. The recovery of the TSB was as the following, firstly the ankle and lower limb of the independent side began to move slightly with in 34 to 75 minutes after the injection and then that of the dependent Secondly the neck and upper limb moved 6 to 15 minutes later than the lower limb. Thirdly the self respiration began to appear between 40 to 80 minutes from the block. The lid and pupil reacted to touch and light respectively between 40 to 80 minutes but the pupil of the independent side responded earlier than that of the depends. Lastly the consciousness recovered completely between 80 to 125 minutes from the block. 3. In the cardiopulmonary function during the TSB, the blood pressure were stable except the 210/130 tory at the and block of case I. There were bradycardias between 65 to 85 minutes in case I and II but no arrythmia on the EKG. The level of the arterial Pco2 was maintained to 43~45 torr during the TSB. 4. The effectiveness of the above blocks was no pain(0%) in case IV, and light (10~20%) in case I and II but no improvement in case III. 5. The right arm weakness has been complicated as to be Injected accidently the "COLD" local anesthetic at the End block of case I.

• Korean Journal of Digital Imaging in Medicine
• /
• v.16 no.1
• /
• pp.13-19
• /
• 2014

Purpose: FLAIR image is beneficial for the diagnosis of various bran diseases including ischemic CVS, brain tumors and infections. However the border between the legion of brain metastasis and surrounding edema may not be clear. Therefore, this study aims to investigate the practical benefits of delayed imaging by comparing the image from a patient with brain metastasis before a contrast enhancement and the image 10 minutes after a contrast enhancement. Materials and methods: Of the 92 people who underwent MRI brain metastases in suspected patients 13 people in three patients there is no video to target the 37 people confirmed cases, and motion artifacts brain metastases in our hospital June-December 2013, 18 people measurement position except for the three incorrect patient (male: 11 people, female: 7 people, average age: 60 years) in the target, test equipment, 3.0T MR System (ACHIEVA Release, Philips, I was 8ChannelSENSE Head Coil use Best, and the Netherlands). TR 11000 ms, TE 125 ms, TI2800 ms, Slice Thickness 5 mm, gap 5 mm, is a Slice number 21, the parameters of the 3D FFE, T2 FLAIR variable that was used to test, TR 8.1 ms, TE 3.7 ms, Slice number 240 I set to. The experiment was conducted by acquiring the FLAIR prior to contrast enhancement (heretofore referred to as Pre FLAIR), and acquiring the 3D FFE CE five minutes after the contrast enhancement, and recomposing the images in an axial plane of S/T 3mm, G 0mm (heretofore referred to as MPR TRA CE). Using the FLAIR 10 minutes after the contrast enhancement (heretofore referred to as Post FLAIR) and Pi-View, a retrospective study was conducted. Using MRIcro on the image of a patient confirmed for his diagnosis, the images before and after the contrast media, as well as the CNR and SNR of the MPR TRA CE images of the lesion and the site absent of lesion were compared and analyzed using a one-way analysis of variance. Results: CNR for Pre FLAIR and Post FLAIR were 34.35 and 60.13, respectively, with MPR TRA CE at 23.77 showing no significant difference (p<0.050). Post-experiment analysis shows a difference between Pre FLAIR and Post FLAIR in terms of CNR (p<0.050), but no difference in CNR between Post FLAIR and MPR TRA CE (p>0.050), indicating that the contrast media had an effect only on Pre FLAIR and Post FLAIR. The SNR for the normal site Pre FLAIR was 106.43, and for the lesion site 140.79. Post FLAIR for the normal site was 107.79, and for the lesion site 167.91. MPR TRA CE for the normal site was 140.23 and for the lesion site 183.19, showing significant difference (p<0.050), and post-experiment analysis shows that there was a difference in SNR only on the lesion sites for Pre FLAIR and Post FLAIR (p<0.050). There was no difference in SNR between the normal site and lesion site for Post FLAIR and MPR TRA CE, indicating no effect from the contrast media (p>0.050). Conclusions: This experiment shows that Post FLAIR has a higher contrast than Pre FLAIR, and a higher SNR for lesions, It was not not statistically significant and MPR TRA CE but CNR came out high. Inspection of post-contrast which is used in a high magnetic field is frequently used images of 3D T1 but, since the signal of the contrast medium and the blood flow is included, this method can be diagnostic accuracy is reduced, it is believed that when used in combination with Post FLAIR, and that can provide video information added to the diagnosis of brain metastases.

• The Journal of Korean Physical Therapy
• /
• v.12 no.2
• /
• pp.175-184
• /
• 2000

This study which applies to the 403 healthy people who don't have particular diseases recently(193 urban aged. 210 rural aged) among male and female aged over 60 years old living in Daegu(city) and Gyungbook(agricultural village) is fulfilled from November 1st to December 31st by interview using the questioned paper which researcher developed, and reached to these tallowing conclusions. 1. Every aged men independent of the place residence answered positively yes but aged women had weak assurance of their health. Especially $38.6\%$ of rural aged women said yes and $51.4\%$ of rural aged women said no. 2. In the sleep and well-regulated life, urban and rural aged generally marked on the sound sleep. Compared with male and female, men answered they had better sleep and regulated life than women. 3. The percentage of the urban and rural aged's judgement on their activity was high and the percentage of the rural aged was lower than the percentage of the urban aged. 4. While $62.6\%$ of urban aged answered they were active. $38.6\%$ of rural female aged answered yes, This shows that the rural female aged regard their health is not good. 5. Compared with same generation. urban aged ranked lower than urban aged in the confidence of physical strength. Especially rural need women answered $42.1\%$ of them were weaker than the same generation. This shows that rural aged women don't have confidence in general physical activities. 6. Taking exercises three times a week which can influence on health cue to sixties and seventies aged ranked $26.1\%$, rarely do is $18.8\%$ and never do is$28.8\%$. Urban and rural aged do not exercise on the purpose of health. 7. The reason of exercise was to advance the physical strength and quality of motion$(34.9\%)$ to get rid of stress$(13.4\%)$ and to prevention of adult illness$(27.8\%)$, prevention of fatness$(15.3\%)$. Aged have a correct understanding that exercise can promote health and protect from the diseases of adult people because the items about the diseases of adult people was marked high. 8. Among the subject of total investigation, 209 persons answered. It showed necessary to recognize that the exercise is still important essential part between adult illness and health care. 9. The $67.7\%$ of urban aged men answered yes in the question of undergoing a physical examination but the rate of not undergoing a physical examination was high in rural aged and urban aged women. According to this, there were the difference of consciousness about health between urban and rural aged. and men and women. 10. Among the people who haying undergone the physical examination, $80.3\%$ of the aged went back to the hospital again because of the result. 11. In the case of stroke, most aged answered the would be placed under medical care. but $53.9\%$ of rural aged women answered they would rely on Chinese medicine. According to this. aged preferred Chinese medicine in some particular diseases. 2. The $58.1\%$ of whole object of this study answered that stroke would be recovered.