• The Korean Journal of Ecology
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• v.23 no.1
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• pp.1-8
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• 2000

The pattern of gap regeneration and vegetational changes were carried out in gaps with different ages and in an intact forest in a Quercus mongolica (mongolian oak) stand located at Munsubong of Mt. Worak. In the early stage of gap formation, Lespedeza maximowiczii, Fraxinus rhynchophylla, Tripterygium regelii, Quercus mongolica, and Stephanadra incisa were dominants in shrub layers. The numbers of shrubs with smaller diameters at ground surface were abundant in the early stage of gap formation. On the other hand, as gap age increased, the number of individuals of Quercus mongolica and Fraxinus rhynchophylla forming tall tree layer decreased. However the diameter at ground surface of Quercus mongolica and Fraxinus rhynchophylla increased. There were few young Quercus mongolica, but those over 130 years old appeared in mature Quercus mongolica stands. The last regeneration episode ended about 130 years ago and the new one started 40 years ago in this study site. Considering the presence of Quercus mongolica below 40 years old in gap and the absence of Quercus mongolica from 40 to 130 years old in closed stand, it is concluded that Quercus mongilica forest is maintained by discontinued regeneration.

• Journal of Life Science
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• v.14 no.5
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• pp.882-890
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• 2004

Gap junction is a membrane structure facilitating the direct transmission of several ions and small molecules between two cells. It is also called an 'intercellular channel' to distinguish it from other well-known cellular channels (e.g. sodium and potassium channels). Gap junction channels are not passive conduits, rather the ion channels modulated by several stimuli including pH, calcium ion, voltage, and a chemical modification (mainly known as phosphorylation). Among them, the effects of voltage on the gating of gap junction channels have been well studied. Gap junction channels are more sensitive to the transjunctional potential ($V_j$) between two cells rather than the membrane potential($V_m$) between inside and outside the cell. In this review, I will summarize the general properties of gap junction channel and discuss the gating mechanism for the gap channels.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.1
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• pp.79-88
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• 2023

In this study, a development of the rust formation arising from steel corrosion was modelled to quantify the structural impact in steel reinforced concrete. The interfacial gap, cover depth and diameter of steel rebar were taken for variables in modelling. It was found that the interfacial gap was the most influencing on the structural limit at steel corrosion, followed by steel diameter and cover depth. At 75 mm of cover depth with 20 mm of the steel diameter, the rust amount to reach cracking accounted for 16.95-27.69 ㎛ to 1-10 ㎛ of the interfacial gap. It was found that there was no risk of cracking and structural limit until the rust was formed within the interfacial gap. With a further formation of rust, the concrete section was successively behaved to yielding, cracking and failure. Additionally, the interfacial gap was the most dominant parameter for the rust amount to reach the cracking of concrete at the interfacial zone, whilst the cover depth had a marginal effect on cracking but had a crucial influence on the rust to failure.

• Korean Journal of Optics and Photonics
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• v.21 no.1
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• pp.6-11
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• 2010

Fluorescent photopolymer film was prepared with composition containing acrylate monomer, binder, a visible light sensitive photo initiator, and fluorescent anthracene polymer. A fluorescent grating pattern was inscribed on the photopolymer film using a 2-beam coupling method. A 514 nm laser was coupled to generate a beam-interference pattern. A highly fluorescent diffractive line pattern was formed on the fluorescent photopolymer within 30 sec. of exposure. The fluorescence intensity was highly enhanced in the patterned area, possibly due to the change in the environment of the fluorescent polymers by the photo-polymerization of monomers. Under a photo-mask, a gap electrode pattern was formed of fluorescent gratings with a sub-micron scale, which was matched well to the calculated value ($2.5\;{\mu}m$ and $0.6\;{\mu}m$) based on the refractive index of the photopolymer and beam incident angle ($3.4^{\circ}$, $15^{\circ}$) to the photopolymer surface.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.6
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• pp.335-349
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• 2017

Submerged breakwaters installed under the water surface are a representative coastal structure to prevent coastal erosion, and various types of submerged breakwaters have been proposed and discussed so far. Generally, submerged breakwaters make the complex wave fields due to abrupt change in water depth at the crown of the breakwater. In this study, wave heights and mean water level formed around a breakwater are examined numerically for three-dimensional permeable submerged breakwaters. OLAFOAM, CFD open source code, is applied in the numerical analysis, and the comparisons are made with available experimental results on the permeable upright wall and the impermeable submerged breakwater to verify its applicability to the three-dimensional numerical analysis. Based on the applicability of OLAFOAM numerical code, the wave height and mean water level distribution formed around the permeable submerged breakwaters are investigated under the formation condition of salient. The numerical results show that as the gap width between breakwaters decreases, the wave height in the center of the gap increases, while it decreases behind the gap, and the installing position of the breakwater from the shoreline has little influence on the change of the wave height. Furthermore, it is found that the decrease of the mean water level near the gap between breakwaters increases with decreasing of the gap width.

• 한국전자현미경학회:학술대회논문집
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• 1999.11a
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• pp.18-18
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• 1999

• Clinics in Shoulder and Elbow
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• v.11 no.2
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• pp.77-81
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• 2008

The goal of rotator cuff repairs is to achieve high initial fixation strength, minimize gap formation, maintain mechanical stability under cyclic loading and optimize the biology of the tendon-bone interface until the cuff heals biologically to the bone. Single row repairs are least successful in restoring the footprint of the rotator cuff and are most susceptible to gap formation. Double row repairs have an improved load to failure and minimal gap formation. Transosseous equivalent repairs (suture bridge technique) have the highest ultimate load and resistance to shear and rotational forces and the lowest gap formation. Even though the superior advantages of double row and transosseous equivalent repairs, those techniques take longer surgical time and are more expensive than single row repairs. Therefore single row repairs can be useful in bursal side partial thickness or small size full thickess rotator cuff tear.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.4
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• pp.153-165
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• 2018

In this study, the performance of irregular wave field generation of olaFlow is first verified by comparing the frequency spectrum of the generated waves by the wave-source using olaFlow and the target wave. Based on the wave performance of irregular waves of olaFlow, the characteristics of the velocity field including the average flow velocity, longshore current and turbulent kinetic energy around the three-dimensional permeable submerged breakwaters, which act as the main external forces of the salient formation, are numerically investigated. The numerical results show that as the gap width between breakwaters decreases, the wave height in the center of the gap increases and as the gap width between breakwaters increases, the longshore currents become stronger. As a result, it is possible to understand the formation of the salient formed behind the submerged breakwaters.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.6
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• pp.399-409
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• 2017

This study numerically investigates the characteristics of the velocity field including the average flow velocity, longshore current and turbulent kinetic energy acting as the main external forces of the salient formed behind the permeable submerged breakwaters. Shoreline response is also predicted by the longshore-induced flux. In this paper, a three-dimensional numerical wave tank based on the OLAFOAM, CFD open source code, is utilized to simulate the velocity field around permeable submerged breakwaters under the formation condition of salient. The characteristics of the velocity field around permeable submerged breakwaters with respect to the gap width between breakwaters and the installing position away from the shoreline under a range of regular waves for different wave height are evaluated. The numerical results revealed that as the gap width between breakwaters increases, the longshore currents become stronger. Furthermore, as the gap width becomes narrower, the point where flow converges moves from the center of the breakwater to the head part. As a result, it is possible to understand the formation of the salient formed behind the submerged breakwaters. In addition, it was found that the longshore currents caused by the gap width between breakwaters and the installation position away from the shoreline are closely related to the turbulent kinetic energy.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.280-282
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• 2005

초파리 초기 발생과정은 gap 유전자, pair-rule 유전자, polarity 유전자의 세 가지 유전자 그룹에 의해서 조직화 된다. Gap 유전자들에 의해 pair-rules 유전자들의 발현이 조절되며, 이들에 의해 결국 polarity 유전자들의 발현을 조절함으로써, 정확한 위치에서 각 기관의 형성을 유도한다. 특히 분열 14단계에서는 pair-rule 유전자 중의 하나인 eve 유전자의 발현이 조절되는데, eve 유전자는 배아의 분할의 줄무늬를 형성시키는 유전자에 해당된다. 본 논문에서는 eve 유전자의 발현조절자인 hunchback, giant, kruppel, bicoid의 gap 유전자들로 구성된 조절 네트워크를 S-system을 이용하여 모델링하였다. 이를 통해 각 유전자들의 발현 데이터로부터 파라미터들을 진화 연산을 통해 예측하고, 각 유전자들의 발현에 대한 시뮬레이션 결과를 보여준다. 예측된 결과와 실제 데이터의 비교는 전체적으로 패턴이 서로 유사함을 보여주고 있다.