• The Journal of Korean Orthopaedic Ultrasound Society
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• v.3 no.2
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• pp.47-53
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• 2010

Purpose: We evaluated the efficacy of ultrasonographic examination of the medial collateral ligament injury in elbow joints in the high school male weight lifting athletes. Materials and Methods: The study group (group I) included 15 male weight lifting athletes (average age: 16.8) and the control group (group II) was demographically matched 9 male with no symptoms on their elbow. Both elbow joint was evaluated through physical examination, plain radiograph, valgus stress view and ultrasonography. Results: On plain radiograph, there was no significant differences (3.6 mm, 2.7 mm; p>0.05) for the medial articular distances between both groups. The valgus stress view revealed the significant increase in group I (right, avr. 5.86 mm and 3.52 mm, p<0.01, left, avr. 5.33 mm and 3.64 mm, p<0.01). On ultrasonography, medial joint space was increased in group I (right, avr. 4.66 mm and 3.29 mm, p<0.01, left elbow 4.28 mm and 3.38 mm, p<0.01). The lateral shifting of proximal ulna also increased in group I (right, avr. 0.73 mm and 1.43 mm, p<0.01, left, avr. 0.96 mm and 1.53 mm, p<0.05). The angular deformity were more prevalent in group I. Conclusion: The medial joint space widening and angular deformity was prevalent in male weight lifting athletes. the ultrasonographic examination was useful in evaluating the degree and incidence of the medial collateral ligament injuries.

• The korean journal of orthodontics
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• v.41 no.5
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• pp.324-336
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• 2011

Objective: The aim of this study was to conduct three-dimensional finite element analysis of individual tooth displacement and stress distribution when a posterior retraction force of 200 g was applied at different positions of the retraction hook on the transpalatal arch (TPA) of a molar, and over different lengths of the lever arm on the maxillary anterior teeth in lingual orthodontics. Methods: A three-dimensional finite element model, including the entire upper dentition, periodontal ligaments, and alveolar bones, was constructed on the basis of a sample (Nissan Dental Product, Kyoto, Japan) survey of Asian adults. Individual movement of the incisal edge and root apex was estimated along the x-, y-, and z-coordinates to analyze tooth displacement and von Mises stress distribution. Results: When the length of the lever arm was 15 mm and 20 mm, the incisal edge and root apex of the anterior teeth was displaced lingually, with a maximum lingual displacement at the lever arm length of 20 mm. When the posterior retraction hook was on the root apex, the molars showed distal displacement. When the length of the lever arm was 20 mm, anterior extrusion was reduced and the crown of the canine displaced toward the buccal side, in which case, the retraction hook was on the edge, rather than at the center, of the TPA. Conclusions: The results of the analysis showed that when 6 anterior teeth were retracted posteriorly, lateral displacement of the canine and lingual displacement of the incisal edge and root apex of the anterior teeth occur without the extrusion of the anterior segment when the length of the lever arm is longer, and the posterior retraction hook is in the midpalatal area.

• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.95-103
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• 1996

Reverse redistribution(RRD) refers to a perfusion defect that develops or becomes more evident on rest imaging compared with the stress imaging. This phenomenon was not uncommonly noted on myocardial perfusion single photon emission computed tomography (SPECT). However, the clinical significance and pathophysiological mechanism of RRD were unclear. The aim of this study was to evaluate the incidence and clinical significance of RRD on either dipyridamole T1-201 or Tc-99m MIBI myocardial perfusion SPECT. RRD was defined as ${\geq}10%$ decrease in relative T1-201 and Tc-99m MIBI uptakes on rest images compared to the stress images or as an appearance of new perfusion defects on rest images. It was observed in both T1-201 (44/463, 9.5%) and Tc-99m MIBI (124/999, 12.4%) myocardial SPECTs similarly, with an overall incidence of 11.5%(168/1462). Many apparent)y unrelated disease groups showed the finding: post-revascularization(53.9%), coronary artery disease(24.6%), myocardial infarction(12.3%), and those with normal coro-nary arteries (9.2%). Clinical and angiographic characteristics of 65 consecutive patients who underwent coronary arteriography in 168 patients who had RRD on myocardial perfusion SPECT were reviewed. Tc-99m MIBI was used in 44 patients, and T1-201 was used in 21 patients. Of the 81 myocardial segments analyzed which showed RRD, 32 segments(39.5%) were in septum, 24(29.5%) in inferior wallL, 12(14.8%) in anterior wall, 7(8.7%) in apex and 6(7.4%) in lateral wall. There was no clear association between RRD and coronary arterial stenosis or Presence of collateral circulations. Ventriculographical wall motion was evaluated in 27 regions with RRD; it was normal in 12 regions, hypokinetic in 12 regions and dyskinetic in 3 regions. In 14 of 21 patients who showed RRD on T1-201 myocardial SPECT, T1-201 reinjection was performed immediately after the 3-4 hour redistribution studies. Ten of 14 (71.4%) showed enhanced T1-201 activity(${\geq}10%$ increased) after reinjection. We conclude that RRD is not related to mode of stress or radiopharmaceuticals. RRD might represent many inhomogeneous pathophysiological processes.

• The korean journal of orthodontics
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• v.36 no.5
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• pp.339-348
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• 2006

Objective: With development of the skeletal anchorage system, orthodontic mini-implant (OMI) assisted on masse sliding retraction has become part of general orthodontic treatment. But compared to the emphasis on successful anchorage preparation, the control of anterior teeth axis has not been emphasized enough. Methods: A 3-D finite element Base model of maxillary dental arch and a Lingual tipping model with lingually inclined anterior teeth were constructed. To evaluate factors influencing the axis of anterior teeth when OMI was used as anchorage, models were simulated with 2 mm or 5 mm retraction hooks and/or by the addition of 4 mm of compensating curve (CC) on the main archwire. The stress distribution on the roots and a 25000 times enlarged axis graph were evaluated. Results: Intrusive component of retraction force directed postero-superiorly from the 2 mm height hook did not reduce the lingual tipping of anterior teeth. When hook height was increased to 5 mm, lateral incisor showed crown-labial and root-lingual torque and uncontrolled tipping of the canine was increased.4 mm of CC added to the main archwire also induced crown-labial and root-lingual torque of the lateral incisor but uncontrolled tipping of the canine was decreased. Lingual tipping model showed very similar results compared with the Base model. Conclusion: The results of this study showed that height of the hook and compensating curve on the main archwire can influence the axis of anterior teeth. These data can be used as guidelines for clinical application.

• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.69-78
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• 2008

Shearing strength test in tension type was investigated to determine the shear resistance of bolt and drift-pin connection of domestic larix glulam. The specimen was connected with bolt and drift-pin in the inserted plate type, and only bolt in the side plate type. The diameter of bolt and drift-pin used in the experiment are 12, 16 and 20 mm. The hole of bolt was drilled at the end-distance 5 d and 7 d. Tension load was loaded in the direction parallel to grain. The shear resistance was evaluated according to end-distance through this, the yield load was compared with the experimental yield load, using Larsen's formula. The prototype design strength is based on the yield load of end-distance 7 d and the reduction factor of end-distance 5 d was calculated. The results were as follows. 1. The average of maximum load of drift-pin connection was higher by 3~30% at the inserted type than at bolt connection with increasing diameter. In bolt connection, the average of maximum load of the side type was 1.54~2.07 times higher than that of the inserted type. In the same diameter, the average of maximum load of end-distance 7 d was higher by 8~44% than that of 5 d. 2. The bearing stress was 1.16~1.41 times higher at the inserted connection than at drift-pin connection, and 1.37~1.86 times higher at 7 d than at 5 d. Also, when the slenderness ratio was below 7.5 at drift-pin connection and below 6.0 at inserted connection, the lateral capacity was good. 3. The ratio of the experimental yield load and the predicted yield load calculated by Larsen's formula proposed by Larsen was 0.80~1.10 at inserted connection, and 0.75~1.46 at side connection. 4. When the inserted bolt connection was based on the yield load of end-distance 7 d, the reduction factor was 0.89 at 12 mm connection, 0.93 at 16 mm and 0.85 at 20 mm. The reduction factor was 0.89 at 12 mm the inserted drift-pin connection, 0.93 at 16 mm, 0.93 at 20 mm. The reduction factor was 0.79 at the side connection of the 12 mm bolt connection and 0.80 at 16 mm.

• Korean Journal of Plant Resources
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• v.10 no.1
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• pp.100-104
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• 1997

A new baekji(Angelica dahurica Bentham et Hooker) variety, Baekji l, was developed through a pure line selection at the Gyeongbug Provincial RDA during the period of 1990 to 1995. The variety was characterized to have high plant height. Long root length and large root diameter as compared with a check varicty of Bonghwa baekji but emergence date, flowering date and leaf number of Baekji l was similar to that of the check variety, and it was also more tolerant to nematode and heat stress. Peeled root color of Backji l was yellowbrown but number of the lateral root of the variety was greater. The dried-root yield of Baekji l in yield trial, regional adaptation trial and farmer's field trial was always $21\sim31%$ higher than that of the check variety.

• Journal of the Korean Geophysical Society
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• v.7 no.3
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• pp.193-206
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• 2004

Geophysical data including chirp (3 7 kHz) subbottom profile and detailed bathymetry were obtained over three seamounts in the Ogasawara Fracture Zone (OFZ) of the western Pacific, as a part of manganese crust survey onboard R/V Onnuri in 2003. The OFZ is a 150-km-wide, 600-km-long rift zone, which separates the East Mariana and Pigafetta Basin. The OFZ is unique in that it includes many seamounts (e.g., Magellan Seamounts andseamounts on the Dutton Ridge). The sub-seafloor acoustic echoes obtained near the OFZ were classified into following types on the basis of their characteristics: types I-1(pelagic sediment with parallel or subparallel reflectors), I-2 (pelagic sediment with no internal reflectors), and III-1 (reef build-up complex) on summit; types II-1 and III-2 (basement outcrop) on flank rift zone and upper slope, respectively; type III-3 (slump) on the lower slope and embayment between the flank rift zones; types II-2 (debrite) on the base of slope and basin floor; and types II-3 (turbidite or pelagic sediment) and II-4 (turbidite) on the basin floor. The mass-wasting that produced the complex of type II-2 debrite and III-3 slump on the lower slope and basin may have been caused by (1) strong tensional stress in the OFZ which may cause the numerous fissures or basement faults and (2) complex of the faults on the summit and steep upper slope. The variations in the echo type of pelagic sediment in the summit of seamounts may be related with the changes in the depositional and/or erosional environments. Type I-2 pelagic sediment, which is characterized by a thin and intermittent coverage, was probably deposited at a sheltered area when the current was strong, whereas type I-1 pelagic deposit occurred during a stage of progressive sedimentation.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.252-252
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• 2017

Nowadays water shortage is becoming one of the biggest problems in the Korea. Many different methods are developed for conservation of water. Soil water management has become the most indispensable factor for augmenting the crop productivity especially on soybean (Glycine max L.) because of their high susceptibility to both water stress and water logging at various growth stages. The farmers have been using irrigation techniques through manual control which farmers irrigate lands at regular intervals. Automatic irrigation systems are convenient, especially for those who need to travel. If automatic irrigation systems are installed and programmed properly, they can even save you money and help in water conservation. Automatic irrigation systems can be programmed to provide automatic irrigation to the plants which helps in saving money and water and to discharge more precise amounts of water in a targeted area, which promotes water conservation. The objective of this study was to determine the possible effect of automatic irrigation systems based on soil moisture on soybean growth. This experiment was conducted on an upland field with sandy loam soils in Department of Southern Area Crop, NICS, RDA. The study had three different irrigation methods; sprinkle irrigation (SI), surface drip irrigation (SDI) and fountain irrigation (FI). SI was installed at spacing of $7{\times}7m$ and $1.8m^3/hr$ as square for per irrigation plot, a lateral pipe of SDI was laid down to 1.2 m row spacing with $2.3L\;h^{-1}$ discharge rate, the distance between laterals was 20 cm spacing between drippers and FI was laid down in 3m interval as square for per irrigation plot. Soybean (Daewon) cultivar was sown in the June $20^{th}$, 2016, planted in 2 rows of apart in 1.2 m wide rows and distance between hills was 20 cm. All agronomic practices were done as the recommended cultivation. This automatic irrigation system had valves to turn irrigation on/off easily by automated controller, solenoids and moisture sensor which were set the reference level as available soil moisture levels of 30% at 10cm depth. The efficiency of applied irrigation was obtained by dividing the total water stored in the effective root zone to the applied irrigation water. Results showed that seasonal applied irrigation water amounts were $60.4ton\;10a^{-1}$ (SI), $47.3ton\;10a^{-1}$ (SDI) and $92.6 ton\;10a^{-1}$ (FI), respectively. The most significant advantage of SDI system was that water was supplied near the root zone of plants drip by drip. This system saved a large quantity of water by 27.5% and 95.6% compared to SI, FI system. The average soybean yield was significantly affected by different irrigation methods. The soybean yield by different irrigation methods were $309.7kg\;10a^{-1}$ from SDI $282.2kg\;10a^{-1}$ from SI, $289.4kg\;10a^{-1}$ from FI, and $206.3kg\;10a^{-1}$ from control, respectively. SDI resulted in increase of soybean yield by 50.1%, 7.0% 9.8% compared to non-irrigation (control), FI and SI, respectively. Therefore, the automatic irrigation system supplied water only when the soil moisture in the soil went below the reference. Due to the direct transfer of water to the roots water conservation took place and also helped to maintain the moisture to soil ratio at the root zone constant. Thus the system is efficient and compatible to changing environment. The automatic irrigation system provides with several benefits and can operate with less manpower. In conclusion, improving automatic irrigation system can contribute greatly to reducing production costs of crops and making the industry more competitive and sustainable.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.344-353
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• 2020

Plants native in Korea have not only ornamental values but also have excellent environmental adaptability, so they can be used as garden plants. Studies on proper volumetric water content (VWC) of substrates have been reported, but many have been conducted in glasshouse conditions where environmental factors were controlled. When considering garden planting, it is necessary to perform the automated irrigation system in outdoor conditions where rainfall occurs at frequent intervals. This research aimed to investigate the VWC suitable for the growth of Minuartia laricina, Arenaria juncea, and Corydalis speciosa in open filed. Sandy soil which consisted of particles of weathered rock was used, and the VWC of 0.15, 0.20, 0.25, and 0.30 ㎥·m^-3 was maintained using an automated irrigation system with capacitance soil moisture sensors and a data logger. No significant differences in growth and antioxidant enzymes activity of A. juncea were observed among VWC treatments. However, the survival rate was low at VWC 0.30 ㎥·m^-3 treatment, which was the highest soil moisture content. Even considering the efficiency of water use, we recommended that VWC 0.15-0.20 ㎥·m^-3 is suitable for the cultivation of A. juncea. Minuartia laricina showed better growth with lower VWC. Because of frequent rainfall in open field, plant volume and survival rate was high even in VWC 0.15 ㎥·m^-3 treatment. In C. speciosa, the plant height, number of shoots and lateral shoots, and fresh and dry weight were higher in plants grown in VWC 0.25 ㎥·m^-3 as compared with that in the plants grown at 0.15, 0.20, and 0.30 ㎥·m^-3. Based on these results, M. laricina needed less water in open filed, and A. juncea and C. speciosa required higher VWC, but excessive water should be avoided.

• Journal of the Korean Arthroscopy Society
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• v.13 no.1
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• pp.8-13
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• 2009

Purpose: We used tibialis allograft for the reconstruction of ACL and used Hybrid femoral fixation utilizing $Endobutton^{(R)}$ and $Rigidfix^{(R)}$ for femoral fixation, and used $Retroscrew^{(R)}$ and additional fixation for tibial fixation to evaluate the clinical results. Materials and Methods: The ACL reconstruction were performed from February 2004 to February 2007 utilizing Hybrid femoral fixation and $Retroscrew^{(R)}$ and 32 patients, 32 cases which were available for year-long observation (12 to 25 months). The clinical results (Lysholm knee score, IKDC grade) and the radiologic results(bone tunnel expansion, Telos anterior displacement test) were evaluated. Results: The Lysholm knee score was improved from the average of $67.9{\pm}5.4$ points (range: 51~77) before operation and to $94.1{\pm}6.8$ points (range: 68~98) at the last follow up (p<0.05). 22 cases (69%) were evaluated normal (A), 9 cases (28%) were evaluated nearly normal (B) and only 1 case (3%) was evaluated not normal (C) at IKDC final evaluation and no case was evaluated abnormal. From $Telos^{(R)}$ stress x-ray evaluation, difference from the opposite knee was improved average 13.2 mm{\pm}5.8 (range: 6~21 mm) to average $3.4\;mm{\pm}2.8$ (range: 0~11 mm) after operation (p<0.05). The femoral and tibial tunnel were widened by 18.7% and 9.6% in the AP view and 12.4% and 8.5% in the lateral view, respectively (p<0.05). However, any statistic significance was not observed between bone tunnel expansion and knee joint functions (p>0.05). Conclusion: An ACL reconstruction with tibialis allograft using Hybrid femoral fixation and $Retroscrew^{(R)}$ enabled anatomical fixation of the graft tendon with satisfactory clinical results.