• Journal of the korean society of oceanography
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• 제32권1호
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• pp.1-7
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• 1997

Surface current fields in the eastern East China Sea (ECS) were constructed by analyzing trajectories of 58 satellite-tracked surface drifters released during 1991-1996. Composite trajectories and 20-minute-by-20-minute box-averaged current vectors show that the basic current pattern composes of: the Kuroshio main stream, which turns eastward toward the Tokara Strait; a northward branch current of the Kuroshio on the ECS outer shelf deeper than 100 m; and an anticyclonic circulation in the northern Okinawa Trough west of Kyushu. The northward branch current sharply changes its direction to the northeast when it crosses a line connecting Cheju Island, Korea and Goto Islands, Japan. The basic pattern of current field changes slightly from winter to summer, and the main axis of the Tsushima Current in the Korea Strait is found to shift seasonally. The drifter experiment does not support the claim that the Yellow Sea Warm Current is separated from the northward branch current on the outer shelf southeast of Cheju Island. We suggest that the use of the term 'Tsushima Current' be limited to the northeast channel flow in the Korea Strait. The new term 'Kuroshio Branch Current' is suggested for the northward branch current on the outer shelf south of Cheju-do, which is separated from the Kuroshio.

• Steel and Composite Structures
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• 제21권3호
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• pp.517-536
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• 2016

Thick steel plate is commonly found with mega steel structures but its properties have not been fully explored. Grade Q345GJ-C steel plate with thickness ranging from 60 mm to 120 mm are studied in this paper. Both the static and cyclic performance of material in different directions (horizontal and through-thickness directions) and locations (outer surface, 1/4 thickness and mid-depth) are experimentally obtained. The accumulative damage during cyclic loading is also calculated by using bilinear mixed hardening (BMH) constitutive relationship together with the Lemaitre's damage model. Results show that the static properties are better at the outer surface of thick steel plates than those at mid-depth. Properties in through-thickness direction are similar to those at mid-depth in the horizontal direction. The cyclic performance at different locations of a given plate is similar within the range of strain amplitude studied. However, when damage parameters identified from monotonic tensile tests are included in the numerical simulation of cyclic loading tests, damage is found accumulating faster at mid-depth than close to outer surface.

• Nuclear Engineering and Technology
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• 제49권1호
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• pp.124-133
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• 2017

In-vessel retention by passive external reactor vessel cooling under severe accident conditions is a viable approach for retention of radioactive core melt within the reactor vessel. In this study, a new and versatile coating technique known as "cold spray" that can readily be applied to operating and advanced reactors was developed to form a microporous coating on the outer surface of a simulated reactor lower head. Quenching experiments were performed under simulated in-vessel retention by passive external reactor vessel cooling conditions using test vessels with and without cold spray coatings. Quantitative measurements show that for all angular locations on the vessel outer surface, the local critical heat flux (CHF) values for the coated vessel were consistently higher than the corresponding CHF values for the bare vessel. However, it was also observed for both coated and uncoated surfaces that the local rate of boiling and local CHF limit vary appreciably along the outer surface of the test vessel. Nonetheless, results of this intriguing study clearly show that the use of cold spray coatings could enhance the local CHF limit for downward-facing boiling by > 88%.

• Applied Microscopy
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• 제45권3호
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• pp.144-149
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• 2015

Nothobranchius guentheri and Nothobranchius patrizii have special life cycle to sustain the dry season. So, we investigated the fertilized eggs morphology, and compared ultrastructures of surface structures and the cross section of fertilized egg envelopes using light and electron microscopes to determine whether these fertilized eggs and egg envelopes show the species specificity or have special structure to sustain the dry season. These fertilized eggs were spherical, yellowish, demersal and adhesive, and had a one-sided large oil droplet. The whip-like structures, adhesive filament were distributed throughout egg envelope in both species. But, that of N. guentheri was covered with fibrous structures, and that of N. patrizii was smooth. The egg envelope consisted of two distinct layers: an outer, electron-dense layer containing adhesive filaments and an inner layer of 16 to 17 horizontal electron-dense lamellae alternating with 15 to 16 interlamellae of lower electron density in both species. The external shapes of fertilized egg and section of fertilized egg envelope were same, but ultrastructure of adhesive filaments on the outer surface was concluded to show species specificity. Our data indicate that the ultrastructural differences of adhesive filament and outer surface of fertilized egg envelope show species specificity although these species belong to same genus.

• Applied Microscopy
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• 제52권
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• pp.6.1-6.5
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• 2022

We examined the morphology of the fertilized egg and the fine structure of fertilized egg envelopes of Poropanchax normani belonging to the family Poeciliidae, also known as Norman's lampeye using light and electron microscopes. The fertilized eggs with narrow perivitelline space were found to be spherical and demersal, additionally containing small oil droplets in the vitelline membrane. Further, a bundle of adhesive filaments was observed to be present on one side of the fertilized egg. These filaments possessed remarkably high elasticity and were approximately 1-3mm in length. The size of the fertilized egg was determined to be about 1.49 ± 0.07mm (n=30). The outer surface appeared smooth, and adhesive filaments originating at different location of the surface of the envelope were found to be distributed around the egg envelope and were joined together to form a single long bundle in scanning electron microscopic observation. A peak-like structure formed of several straight wrinkles was observed around the micropyle. However, the complete structure of the micropyle could not be studied due to the depth at which it was located. Additionally, the total thickness of the egg envelope was ascertained to be approximately12.5-14.5㎛. The egg envelope consisted of two distinct layers, an outer electron dense layer and an inner lamellar layer, further consisting of 10 sublayers of varying thicknesses. Collectively, it was observed that the morphological characteristics of the fertilized egg, fine structures surrounding the micropyle, outer surface, adhesive structure consisting adhesive filaments, and sections of fertilized egg envelope displayed species specificity.

• Nuclear Engineering and Technology
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• 제31권2호
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• pp.182-191
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• 1999

The sorption of UO$_{2}$$^{2+}$ onto goethite and kaolinite under various experimental conditions was successfully interpreted using surface complexation modeling (SCM). The SCM approach used in this work is the triple-layer model (TLM) in which weakly bonded ions are modeled as outer-sphere (ion-pair) complexes and strongly bonded ions as inner-sphere (surface coordination) complexes. The change of ionic strength did not affect the U(VI) sorption onto goethite, thus the formation of inner-sphere surface complexes, (FeO)$_2$UO$_2$ and (FeO)$_2$(UO$_2$)$_3$OH$_{5}$ was assumed to simulate the effects of ionic strength and goethite concentration. On the other hand, the U(VI) sorption onto kaolinite showed ionic strength dependence, thus the formation of AlO-UO$_{2}$$^{2+}$(outer-sphere complex) and SiO(UO$_2$)$_3$OH$_{5}$ (inner-sphere complex) was assumed to simulate the experimental data. In the presence of carbonates, the sorption of U(VI) onto kaolinite decreased in the weakly alkaline pH range. This was well simulated assuming the formation of a outer-sphere surface complex, A1OH$^{2+}$- (UO$_2$)$_2$CO$_3$OH$_3$. Since SCM approach uses thermodynamic data such as surface complexation constants, it is more predictive than empirical modeling approach in which conditional values such as partition coefficient are used. used.

• 항공우주정책ㆍ법학회지
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• 제22권1호
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• pp.55-74
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• 2007

When the People's Republic of China destroyed one of its own defunct meteorological satellites, the Fengyun-1C, at an altitude of some 865 km above the earth's surface, the PRC was accused of initiating, or at the very least risking an(other) arms race in outer space also. The test also gave rise to a few legal questions as to the permissibility of this test, and the broader permissibility of using space for military and other weapon-touting activities, Whilst the test cannot be considered to constitute a direct threat to international peace and security so as to invoke relevant legal principles and consequences in terms of the UN Charter for example, it highlights the importance of such clauses in international space law as requiring international cooperation and consultation, due regard for the interests of all other countries both on earth and in outer space, and the further development of general regimes of registration and space debris-prevention. From that perspective, the PRC violated international outer space law not so much by the test itself but by the accompanying lack of information, consultation and due regard for other states', and indeed mankind's, interests.

• 항공우주정책ㆍ법학회지
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• 제spc호
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• pp.181-199
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• 2007

When the People's Republic of China destroyed one of its own defunct meteorological satellites, the Fengyun-1C, at an altitude of some 865 km above the earth's surface, the PRC was accused of initiating, or at the very least risking an(other) arms race in outer space also. The test also gave rise to a few legal questions as to the permissibility of this test, and the broader permissibility of using space for military and other weapon-touting activities, Whilst the test cannot be considered to constitute a direct threat to international peace and security so as to invoke relevant legal principles and consequences in terms of the UN Charter for example, it highlights the importance of such clauses in international space law as requiring international cooperation and consultation, due regard for the interests of all other countries both on earth and in outer space, and the further development of general regimes of registration and space debris-prevention. From that perspective, the PRC violated international outer space law not so much by the test itself but by the accompanying lack of information, consultation and due regard for other states', and indeed mankind's, interests.

• Applied Microscopy
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• 제47권2호
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• pp.70-74
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• 2017

In the case of genus Nothobranchius, Nothobranchiidae, the morphology of fertilized eggs and ultrastructures of fertilized egg envelopes have been reported in only two fishes. Therefore it is hard for sure to these morphological characteristics show genus specificity because of lower research samples. So, we studied the morphology of fertilized egg, and compared the ultrastructures of outer surface, micropyle, and section of fertilized egg envelopes under the light and electron microscopes from the other two species, Nothobranchius foerschi and Nothobranchius rachovii, Nothobranchiidae to find out whether these structures have the species specificity or not. Both fertilized eggs were spherical, demersal and adhesive, and have a large oil droplet. The adhesive whip-like structures were distributed on the outer surface of egg envelope, and a micropyle located on the animal pole. The fertilized egg envelope consisted of two distinct layers: an outer electron-dense layer with adhesive structures and an inner lamellae layer in both species. The external shapes of fertilized egg and ultrastuctures of outer surface, micropyle, and section of fertilized egg envelope have same structure including results before. Our data indicate that these morphological characteristics of fertilized egg and fertilized egg envelope show genus Nothobranchius specificity.

• Korean Chemical Engineering Research
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• 제58권2호
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• pp.280-285
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• 2020

We have developed a constitutive display system of the Pseudomonas fluorescens SIK W1 TliA lipase on the cell surface of Escherichia coli using E. coli outer membrane protein C (OmpC) as an anchoring motif, which is an economical compared to induced system. For the constitutive expression of truncated OmpC-TliA fusion proteins, gntT104 promoter was employed. Cell growth was not affected by over expression of fusion protein during entire culture time, suggesting cell lysis was not a problem. The localization of truncated OmpC-TliA fusion protein on the cell surface was confirmed by immunofluorescence microscopy and measuring whole cell lipase activity. Constitutively displayed lipase was very stable, retaining activity enantioselectivity throughout the five repeated reactions. These results suggest that OmpC from E. coli be a useful anchoring motif for displaying enzymes on the cell surface without any inducers, and this stable surface display system can be employed for a broad range of biotechnological applications.