• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.5
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• pp.407-411
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• 2005

A simulation investigation on the circular cylindrical reentrant cavity with axial ridges and a cylindrical circumferential slot is presented. This study indicates that by properly adjusting the dimensions of the ridge sand the slot, the size of the cavity can be miniaturized to around $\lambda_0$ The simulation results using CST MWS show good agreement with past theoretical predictions and provide useful insight into fundamental concerns associated with electrically small antennas.

• Journal of the Korean Arthroscopy Society
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• v.6 no.1
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• pp.25-30
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• 2002

Purpose : To evaluate the clinical results of displaced tibial intercondylar eminence fractures which were treated with transpatellar cannulated screw fixation. Materials and Methods : Ten patients with displaced tibial intercondylar eminence fractures were treated between December 1998 and May 2001 and then followed up for more than one year. They were treated arthroscopic reduction and fixation of fracture site by cannulated screw through the hole of nonarticular surface of inferior patella. They were prospectively evaluated with regard to their clinical and radiologic results. Results : Radiologic unions occurred at an average of 9.2 weeks. Average anterior displacements were 1.8 mm in stress x-rays and 1.1 mm in KT-2000 arthrometer. Average loss of extension was $4.1^{\circ}$. Functional results were excellent in 7 cases and good in 3 cases. Conclusion : Arthroscopic transpatellar cannulated screw fixation is one of the useful methods for the treatment of displaced tibial intercondylar eminence fractures.

• Journal of the Korean Society of Visualization
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• v.21 no.2
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• pp.91-101
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• 2023

In this study, we investigated how the performance of a Venturi changes when a hemispherical bump is applied to the divergent part of the Venturi tube and what causes the performance difference. The Venturi-tunnel experiment was conducted in the Reynolds number range of 0.2 × 10⁵ - 1.2 × 10⁵ and cavitation number range of 0.9 - 10. The bump was found to reduce the pressure loss coefficient and increase the discharge coefficient by shortening the cavitation length. The decrease in the cavitation length by the bump was explained by the strengthening of the re-entrant jet. The wake generated from the hemispherical bump seems to increase the adverse pressure gradient on the Venturi surface, thereby strengthening the re-entrant jet.

• Journal of the Korean GEO-environmental Society
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• v.15 no.6
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• pp.49-56
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• 2014

The stability of tunnel construction depends entirely on the characteristics of the soil strength. If the soil strength is weak, collapse of tunnel occurs frequently under construction. In general, it copes with collapse by conducting half section excavation or reinforcement in advance under these conditions. Nevertheless, it can be collapsed under upper section excavation in the weathered fracture zone and it can be recovered through the application of reinforcement. As it has a bad influence on the upper section in case of upheaveal of tunnel bottom, it can be adversely affected on the overall stability of the tunnel. Thus, an in-depth review of reinforcement is needed in poor bottom ground. As the practices that has a bad affect on the stability of the tunnel due to upheaveal of tunnel bottom is increasing, research is needed for applicable standards for reinforcement. In this paper, it were investigated at actual field cases of upheaveal of bottom ground and characteristics of behavior and reinforcement measures were analyzed.

• Journal of the Korean earth science society
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• v.33 no.6
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• pp.534-543
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• 2012

The relationship between tectonic uplift and geophysical analysis of gravity anomalies and the in-situ stress fields in the Otway Ranges, SE Australia is addressed in this study to understand the nature and possible mechanism for the neotectonic movements. The uplift axis of the ranges is coincident with the regional Bouguer gravity highs whereas thick Tertiary sedimentary successions are highly correlated with the gravity lows along the basin rift geometry. This result suggests that the gravity highs are separated by the thick Tertiary sedimentary successions. Regional structural trends associated with faults and foldings of the deformed surfaces are consistent with the prevailing NW-SE $S_{Hmax}$ trend in this part of the continent. The anomalously positive correlation between topography and Bouguer gravity fields suggests possibly a lithospheric flexural deformation mode at a long wavelength (order of $10^2$ kms) in the region. It also suggests that the reactivation of pre-existing lithospheric structures driven by plate boundary forces plays a key role in this mode.

• 대한관절경학회:학술대회논문집
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• 2007.10a
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• pp.87-88
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• 2007

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.5
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• pp.378-384
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• 1990

A neritic copepod previously known as Acartia clausi Giesbrecht in the Korean waters was taxonomically re-examined, and the species has been identified as Acartia omorii and Acartia hudsonica. These species are easily discriminated by the morphology of the 3rd segment of the 5th right leg in male and by the shape of the genital segment in female. A. omorii occurs along the coast of Korea, and A. hudsonica is restricted to the brackish waters of Pusan area.

• Journal of the Korean Arthroscopy Society
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• v.3 no.2
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• pp.127-131
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• 1999

Avulsion fractures of the intercondylar eminence of the tibia are not uncommon. In the displaced avulsion fracture, anatomical reduction and firm fixation of fracture fragments are needed but the most of the conventional operative techniques including arthroscopic technique are relatively complex and need. The results were not always satisfactory due to the risk of postoperative complications such as wound infection, premature epiphyseal closure and loss of fixation after early motion etc. So we describe a simple and safe modified method of arthroscopic reduction and fixation for avulsion fractures of the intercondylar eminence of the tibia. In our thirteen cases, we achieved anatomical reduction and secure fixation using cannulated screw through the three arthroscopic portals (anterolateral, medial mid-patellar and central). Postoperatively, immediate limited range of motion of the knee and partial weight bearing were possible. Additional use of the washer afforded safe fixation of comminuted avulsion fracture. The advantage of this technique includes its technical simplicity, easy removal of hardware, ability to treat comminuted type IV fracture with washer, no additional skin incision, no damage to growing plate in growth children and less morbidity.

• Journal of the Korean Arthroscopy Society
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• v.13 no.3
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• pp.254-258
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• 2009

Tibial eminence fracture is caused by distortion, excessive flexion and extension, varus and valgus injury of the knee joint in the form of avulsion fracture. A failure over the exact anatomical reduction of fragment can lead to instability and limitation of joint motion. Recently, a variety of arthroscopic assisted reduction and fixation technique have been used. In the tibial eminence fracture, we created an arthroscopic pull-out wire fixation technique using a cannulated screw that is easy and more convenient than in the conventional technique. So we report this technique with a review of current literatures.

• Journal of the Korean Geographical Society
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• v.47 no.3
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• pp.328-346
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• 2012

This study provides quantitative constraints on Neogene uplift in the Korean peninsula using onshore paleo-shoreline records and seismic data. The eastern margin of Northeast Asia including Korea sits in the back-arc system behind the Western Pacific Subduction Zone, a complex trench triple junction of the Philippine Sea, Pacific, and Eurasian (Amurian) plates. An analysis of seismic data in the subduction zone shows that the pattern of uplift in the peninsula mirrors the extent of deep seismicity in subducting Pacific plate beneath. Combined with previous tomographic studies it is proposed that uplift is partly driven by asthenospheric upwelling caused by a sinking slab during the Neogene. In addition, the SHmax orientations of E-W and N-S trends in the peninsula are consistent with the prevailing in-situ stress fields in the eastern Eurasian continent generated by various plate boundary forces. The uplift in Korea during the Late Neogene is attributed, in part, to lithospheric failure relating to faulting movements, thus providing a link between dynamic effects of mantle upwelling at sinking slab edge and lithospheric responses driven by plate boundary forces.