• Journal of Environmental Science International
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• v.11 no.11
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• pp.1141-1147
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• 2002

Based on the tide gauge data from the Permanent Service for Meau Sea Level (PSMSL) collected at 23 locations in the Korean coast, the long-term sea-level trend was computed using a simple linear regression fit over the recorded length of the monthly mean sea-level data. The computed sea-level trend was also corrected for the vertical land movement due to post glacial rebound(PGR) using the ICE-4G(VM2) model output. It was found that the PGR-corrected sea-level trend near Korea was 2.310 $\pm$ 2.220 mm/yr, which is higher than the global average at 1.0∼2.0mm/yr, as assessed by the Intergovernmental Panel on Climate Change(IPCC). The regional distribution of the long-term sea-level trend near Korea revealed that the South Sea had the largest sea-level rise followed by the West Sea and East Sea, respectively, supporting the results of the previous study by Seo et al. However, due to the relatively short record period and large spatial variability, the sea-level trend from the tide gauge data for the Korean coast could be biased with a steric sea-level rise by the global warming during the 20th century.

• Journal of Mechanical Science and Technology
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• v.15 no.8
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• pp.1165-1173
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• 2001

This paper deals with dynamic analysis of Pipeline Inspection Gauge (PIG) flow control in natural gas pipelines. The dynamic behaviour of PIG depends on the pressure differential generated by injected gas flow behind the tail of the PIG and expelled gas flow in front of its nose. To analyze dynamic behaviour characteristics (e.g. gas flow, the PIG position and velocity) mathematical models are derived. Tow types of nonlinear hyperbolic partial differential equations are developed for unsteady flow analysis of the PIG driving and expelled gas. Also, a non-homogeneous differential equation for dynamic analysis of the PIG is given. The nonlinear equations are solved by method of characteristics (MOC) with a regular rectangular grid under appropriate initial and boundary conditions. Runge-Kutta method is used for solving the steady flow equations to get the initial flow values and for solving the dynamic equation of the PIG. The upstream and downstream regions are divided into a number of elements of equal length. The sampling time and distance are chosen under Courant-Friedrich-Lewy (CFL) restriction. Simulation is performed with a pipeline segment in the Korea gas corporation (KOGAS) low pressure system. Ueijungboo-Sangye line. The simulation results show that the derived mathematical models and the proposed computational scheme are effective for estimating the position and velocity of the PIG with a given operational condition of pipeline.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.540-544
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• 1991

Pod dehiscence in six rape varieties drying after harvest in the field was investigated with use of strain gauge. The development of rape pods was observed after 3-4 days of flowering. The length of pod and seed reached of their maximal size at the 20th and 35th days after flowering, respectively. The seed shape was nearly spherical 40 days after flowering, and pod width was maximal at the 45th days of flowering. Moisture content of seeds was 70% at cutting time, reduced to 30% at 5 days of drying in the plastic film house and 10% at 14 days. Pod dehiscence showed a diurnal change with moisture content of pods and relative humidity, and the dehiscence became difficult under low moisture content of pods and relative humidity of which seems to be related to the rapid drying condition of pod.

• Journal of Mechanical Science and Technology
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• v.17 no.5
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• pp.629-636
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• 2003

This paper introduces the developed geometry PIG (Pipeline Inspection Gauge), one of several ILI (In-Line Inspection) tools, which provide a full picture of the pipeline from only single pass, and has compact size of the electronic device with not only low power consumption but also rapid response of sensors such as calipers, IMU and odometer. This tool is equipped with the several sensor systems. Caliper sensors measure the pipeline internal diameter, ovality and dent size and shape with high accuracy. The IMU (Inertial Measurement Unit) measures the precise trajectory of the PIG during its traverse of the pipeline. The IMU also provide three-dimensional coordination in space from measurement of inertial acceleration and angular rate. Three odometers mounted on the PIG body provide the distance moved along the line and instantaneous velocity during the PIG run. The datum measured by the sensor systems are stored in on-board solid state memory and magnetic tape devices. There is an electromagnetic transmitter at the back end of the tool, the transmitter enables the inspection operators to keep tracking the tool while it travels through the pipeline. An experiment was fulfilled in pull-rig facility and was adopted from Incheon LT (LNG Terminal) to Namdong GS (Governor Station) line, 13 km length.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.448-448
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• 2000

This paper deals with dynamic behaviour analysis for pipeline inspection gauge (PIG) flow control in natural gas pipeline. The dynamic behaviour of the PIG is depending on the different Pressure between the rear and nose parts, which is generated by injected gas flow behind PIG's tail and expelled gas flow in front of its nose. To analyze the dynamic behaviour characteristics such as gas flow in pipeline, and the PIG's position and velocity, mathematical model is derived as two types of a nonlinear hyperbolic partial differential equation for unsteady flow analysis of the PIG driving and expelled gas, and nonhomogeneous differential equation for dynamic analysis of PIG. The nonlinear equation is solved by method of characteristics (MOC) with the regular rectangular grid under appropriate initial and boundary conditions. The Runge-Kuta method is used when we solve the steady flow equations to get initial flow values and the dynamic equation of PIG. The gas upstream and downstream of PIG are divided into a number of elements of equal length. The sampling time and distance are chosen under Courant-Friedrich-Lewy (CFL) restriction. The simulation is performed with a pipeline segment in the Korea Gas Corporation (KOGAS) low pressure system, Ueijungboo-Sangye line. The simulation results show us that the derived mathematical model and the proposed computational scheme are effective for estimating the position and velocity of PIG with different operational conditions of pipeline.

• Korean Journal of Heritage: History & Science
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• v.42 no.1
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• pp.4-19
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• 2009

Total 57 sauropod tracks are found from the Cretaceous Kyokpori Formation in the Buangun, Jeollabukdo, Korea. Six sauropod trackways in second stratigraphic level of three stratigraphic levels were recognized and described. The type of sauropod trackways is a wide-gauge trackway which has been generally in Cretaceous sauropod trackways. On the basis of foot length, trackway orientations, and preservation, all of the tracks are thought to have been made by small sauropods moving not only towards and away from the shoreline but also along the shoreline of lacustrine environment.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.290-300
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• 1995

Tooth mobility is one of the most important clinical parameters in examination, diagnosis, prognosis and treatment planning procedure. In order to determine the differences of tooth mobility according to radiographical bone level, clinical root length, clinical crown/root ratio, and bleeding on probing, 90 male adults with periodontal disease and 10 male adults with periodontal health($25{\sim}45$ years old) were selected through clinical examinations including occlusal relationship, probing depth, attachment level, and bleeding on probing. On the mandibular anterior teeth, standard periapical radiographs were taken, and tooth mobility was measured by Periotest(Siemens Co., Germany). The radiographic bone level of individual tooth was evaluated as coronal 1/3, middle 1/3, and apical 1/3 to anatomical root length, and clinical crown length from incisal edge to bone level and clinical root length from bone level to root apex were measured with Boley gauge, and subsquently clinical crown/root ratio was calculated. The difference of tooth mobility(Periotest value) according to radiographical bone level, clinical root length, clinical crown/root ratio, and bleeding on probing was statistically analyzed by unpaired Student t-test. Tooth mobility was significantly higher in bleeding group than non-bleeding group on probing in the teeth radiographic bone level of middle 1/3, with clinical root length longer than 6mm, and with clinical crown/root ratio over 0.3(p<0.01). But there was no statistical difference in tooth mobility between bleeding group and non-bleeding group on probing in the teeth with radiographic bone level of apical 1/3, with short clinical root length less than 5mm, and with clinical crown/root ratio under 0.2(p>0.05). The results note that the tooth mobility depends on clinical root length, clinical crown/root ratio and gingival inflammation, and in the teeth with relatively good alveolar bone support gingival inflammation is one of the most important factors that affect tooth mobility.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.1
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• pp.54-65
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• 1996

The purposes of this study were 1) to present the optimum slacks pattern for young men, 2) to develope a methodology to draft basic slacks pattern using AutoCAD The total crotch legth and the shape of the crutch line were determined by anthropometric data analysis. The total crotch length was calculated with the waist girth, the hip girth and the crotch length measurements. The anthropometric data utilized for this procedure was National Anthropometric Survey of Korea, 1992. And multidimensional anthropometric measurements were carried out for 6 male college students between the age of 18 to 24. The subjects were measured with the Martin's anthropometer and the sliding gauge. Mean, standard deviation and t-test were performed for statistical analysis of the data. The automatic drafting method was programmed by AutoLISP in AutoCAD. The automatic drafting was based on the Muller's slacks pattern drafting method, the measurements of slacks construction components and the curve of crotch line. The crotch line was drafted using of the arc function in AutoCAD. The total crotch length was calcuated using the multiple regression equation. The experimental pattern developed to accomodate individual body wleasurements expected to produce customized apparel production in QRS(Quick Response System) production system.

• Clinics in Orthopedic Surgery
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• v.10 no.4
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• pp.407-412
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• 2018

Background: We conducted this study to determine the optimal length of patellar and tibial bone blocks for the modified transtibial (TT) technique in anterior cruciate ligament (ACL) reconstruction using the bone-patellar tendon-bone (BPTB) graft. Methods: The current single-center, retrospective study was conducted in a total of 64 patients with an ACL tear who underwent surgery at our medical institution between March 2015 and February 2016. After harvesting the BPTB graft, we measured its length and that of the patellar tendon, patellar bone block, and tibial bone block using the arthroscopic ruler and double-checked measurements using a length gauge. Outcome measures included the length of tibial and femoral tunnels, inter-tunnel distance, length of the BPTB graft, patellar tendon, patellar bone block, and tibial bone block and graft-tunnel length mismatch. The total length of tunnels was defined as the sum of the length of the tibial tunnel, inter-tunnel distance and length of the femoral tunnel. Furthermore, the optimal length of the bone block was calculated as (the total length of tunnels - the length of the patellar tendon) / 2. We analyzed correlations of outcome measures with the height and body mass index of the patients. Results: There were 44 males (68.7%) and 20 females (31.3%) with a mean age of 31.8 years (range, 17 to 65 years). ACL reconstruction was performed on the left knee in 34 patients (53%) and on the right knee in 30 patients (47%). The optimal length of bone block was 21.7 mm (range, 19.5 to 23.5 mm). When the length of femoral tunnel was assumed as 25 mm and 30 mm, the optimal length of bone block was calculated as 19.6 mm (range, 17 to 21.5 mm) and 22.1 mm (range, 19.5 to 24 mm), respectively. On linear regression analysis, patients' height had a significant correlation with the length of tibial tunnel (p = 0.003), inter-tunnel distance (p = 0.014), and length of patellar tendon (p < 0.001). Conclusions: Our results indicate that it would be mandatory to determine the optimal length of tibial tunnel in the modified TT technique for ACL reconstruction using the BPTB graft. Further large-scale, multi-center studies are warranted to establish our results.

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1011-1018
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• 1997

Background : To evaluate how efficaciously and safely we can make transthoracic lung biopsy with an 18-gauge automated biopsy device. Methods : We performed 130 transthoracic needle biopsies including 16 repeat biopsies in 114 patients with a pulmonary mass using an l8-gauge biopsy device (ASAP 18, Microvasive-. Eighty-three biopsies were performed by an experienced radiologist and 47 by several less experienced radiologists. All biopsies were guided by biplane fluoroscopy. Results : We successfully obtained sufficient tissue(>2-mm in the length) in 128(985) of 130 biopsies. Biopsy provided the specific diagnosis in 97 (85%) of 114 patients including 78 (88%) of 89 patients with a malignant tumor and 19 (90%) of 21 patients with a benign condition. The diagnosis could not be made in the remaining four patients. Of interest to note was the superb capability (74/74) of biopsy to make a distinction between small cell carcinoma and non-small cell carcinoma. There was no significant difference in the diagnostic yields between the experienced and less experienced radiologists. Of the total 130 biopsies, pneumothorax appeared in 13 (10%), among which treatment was required in 2 (2%), Mild, self-limiting hemoptysis was nod in seven (5%), but in no case was the treatment required. Conclusion : We conclude transthoracic lung biopsy with an 18-gauge automated device is an effective procedure for the specific diagnosis of benign and malignant lung disease. It is safe with the complication rate comparable to that of fine-needle aspiration biopsy as well.