• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.805-809
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• 2015

The species composition of bycatch species in the coastal waters of Yeosu were determined by monthly sample collection using a gape net with wings in 2014. Of a total of 32 fishes collected, the dominant species were Ammodytes personatus, Conger myriaster leptocephali, Sebastes inermis, Trichiurus lepturus, Thryssa kammalensis, Leiognathus nuchalis, Syngnathus schlegeli, Thryssa adelae and Hexagrammos otakii. These 9species accounted for 95.2% of the total number of individuals collected. Most of the fish caught were juveniles and small fishes. Based on the results of multidemensional scaling (MDS) analysis, the bycatch fishes were divided into five group.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.10
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• pp.1116-1120
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• 2010

Low cost patch array antenna for high sensitivity electromagnetic(EM) sensor is presented. The operating frequency band of the antenna is 24.05~24.25 GHz. Array structure is the symmetrical pattern by Chebyshev polynomial and the feed point is located in the middle of the array. Also, the gain of the array antenna can be increased by the side wings which are connected with the ground plane. It is proved through simulation and the measurement results that the operating frequency and the side-lobe level(SLL) are rarely changed when the inclined angle of the side wings is varied.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.2151-2156
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• 2003

The distinguishing features of flows at high angles of attacks are caused by the generation of free shear layers at sharp leading edges, by separation of the viscous layers from the surfaces of wings and bodies and by the flow in the wakes of the wings and bodies. In this study, systematic approach by PIV experimental method within a circulating water channel was adopted to study the fundamental characteristics of induced vortex generation, development and its breakdown appearing on a delta wing model with or without LEX in terms of four angles of attack($15^{\circ}$, $20^{\circ}$, $25^{\circ}$, $30^{\circ}$) and six measuring sections(30%, 40%, 50%, 60%, 70%, 80%) of chord length. Distributions of time-averaged velocity vectors and vorticities over the delta wing model were compared along the chord length direction. Highly swept leading edge extension(LEX) applied to delta wings has greatly improved the subsonic maneuverability of contemporary fighters. High-speed CCD camera which made it possible to acquire serial images is able to get the detailed information about the flow characteristics occurred on the delta wing. Especially quantitative comparison of the maximum vorticity featuring the induced pressure distribution were also conducted to clarity the significance of the LEX existence.

• Aerospace Engineering and Technology
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• v.8 no.2
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• pp.149-159
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• 2009

This paper deals with an analytical study on the aileron reversal characteristics of anisotropic composite aircraft wings modelled as thin-walled beam and having extension-twist structural couplings caused by Circumferentially Uniform Stiffness (CUS) layup scheme. For a study on the aileron reversal of CUS composite wings, it is essential to consider the following effects such as extension-twist structural coupling, wing aspect ratio, and ratio of span-wise and chord-wise length of aileron to wing, initial angle of attack, and sweep angle, etc. The results on the aileron reversal could have a significant role in more efficient designs of thin-walled composite wing aircraft for which this aeroelastic instability is one of the most critical ones.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.759-764
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• 2003

Numerical simulations are conducted to investigate the mechanism of hovering flight by single flapping wing, and to examine the effect of the phase difference between the fore- and hindwings in hovering flight by two flapping wings. The numerical method used is based on an immersed boundary method in Cartesian coordinates. The Reynolds number considered is Re=150 based on the maximum translational velocity and chord length of the wing. For single flapping wing, the stroke plane angles are $0^{\circ}$, $30^{\circ}$, $60^{\circ}$, $75^{\circ}$ and $90^{\circ}$ and the downstroke angles of attack are varied for each stroke angle. Results show that for each stroke plane angle, there is an optimal angle of attack to maximize the vertical force. Below the stroke angle of $60^{\circ}$, wake capturing reduces the negative vertical force during the upstroke. For two flapping wings, The phase lags of the hindwing are $0^{\circ}$, $90^{\circ}$, $180^{\circ}$ and $270^{\circ}$. The amplitudes of the stroke are 2.5 and 4.0 times the chord length at each phase lag. The results show that maximum vertical force is generated when the phase lag is zero, and the amplitude of the vertical force is minimum at the phase lag of $180^{\circ}$.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.12
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• pp.1192-1200
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• 2009

This paper deals with an analytical study on the aileron reversal characteristics of anisotropic composite aircraft wings modelled as thin-walled beam and having bending-torsion structural couplings caused by Circumferentially Asymmetric Stiffness layup scheme. For a study on the aileron reversal of CAS composite wings, it is essential to consider the following effects such as warping restraint, transverse shear flexibility, bending-twist structural coupling, wing aspect ratio, ratio of span-wise and chord-wise length of aileron to wing, and sweep angle, etc. The results on the aileron reversal could have a significant role in more efficient designs of thin-walled composite wing aircraft for which this aeroelastic instability is one of the most critical ones.

• Animal Systematics, Evolution and Diversity
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• v.31 no.2
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• pp.122-127
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• 2015

The subfamily Ennominae is one of the most species-rich taxa of Geometridae that include more than 9,700 species worldwide and over 280 species in South Korea. Herein, we present the first report of five species of Ennominae. Abraxas flavisinuata can be characterized by the white wings, a thick black postmedial line that is medially and dorsally broken with an orange band, large rounded black discal dots on the forewing, and a black dotted postmedial line on the hindwing. Lomographa claripennis can be characterized by the whitish wings, the black undulating postmedial line as well as the minute blackish discal dot on the forewing, and the black undulating postmedial line with a minute black discal dot on the hindwing. Arichanna tetrica can be characterized by the grayish forewings, thick black transverse ante- and postmedial lines, a large blackish discal dot, whitish apical streak on the forewing, and scattered black dots on the whitish hindwing. Apocleora rimosa can be characterized by the brown ground color of the fore- and hindwings, the black slanted ante- and postmedial lines of the forewing, and two black medial lines on the hindwing. Ourapteryx japonica can be characterized by the white wings, the dark brown transverse ante- and postmedial lines with a long discal dot on the forewing, and the dark brownish transverse antemedial line as well as a termen that has a sharp white tail with one large dark reddish dot and one small black dot on the hindwing.

• English & American cultural studies
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• v.9 no.1
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• pp.27-50
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• 2009

Henry James tries to describe minutely in The Wings of the Dove the process in which a bad faith grows, is practiced in one's self, and spreads to a society. Through this fictional specificity, he embodies an analogy between a bad faith and social role-playing. That is, he shows, through the main characters such as Milly Theale and Merton Densher, how self interacts with the other and a society. In this interaction, there is some essential element, namely, an organic relationship between a self identity and a social role-model, which James describes very meticulously. Therefore, the characters are depicted as seeking to define self identity and eventually distorting it. Thus, The Wings of the Dove can be seen as a tragedy in which the characters who have this wrongly distorted self identity come to experience its effects. The distorted self identity appears to function as a social role. Milly distorts her true self identity by internalizing a dove-image for it. This results in a bad faith. Moreover, the American girl Milly utilizes it as a convenient social role-model which makes it easy for her to interact and engage with the others in the European society. Merton also evades adventurous and painful self-reflection and self-criticism by sticking to the mannerisms of gentlemanship and imitates the sublimity which Milly shows him. Thus, Milly and Merton clearly omit self-inspection and self-inquiry for the contact between a free self and a society, which is essential to obtain social objectivity, namely, intersubjectivity.

• Advances in aircraft and spacecraft science
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• v.9 no.2
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• pp.119-130
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• 2022

Supersonic projectiles like rockets, missiles, or aircraft find various applications in the field of defense. The shape of the wings is mainly designed as wedge shape or delta wings for supersonic vehicles. The study of supersonic flows over the wedges and flat plate delta wings around the large scale of incidence angle is considered in the supersonic projectile. In the present paper, the prime attention is to study the pressure at the nose of the plane wedge over the various Mach number and the various angles of incidence. Ghosh piston theory is used to obtain the pressure distribution analytically, and the results are compared with CFD analysis results. The wedge angle and Mach number are the parameters considered for the research work. The range of wedge angle is 50 to 250, and Mach number is 1.5 to 4.0 are considered for the current research work. The analytical results show excellent agreement with the CFD results. The results show that both the parameters wedge angle and Mach number are influential parameters to vary the static pressure. The static pressure increases with an increase in Mach number and wedge angle.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.404-418
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• 2013

In this study, we conducted field surveys to investigate and analyze species and length composition of catch from gape net with wings being set in two areas - Masari, Supomri - located in southern part of Jin-do for understanding fishing characteristics of gape net with wings fishery from March to September of 2011. And with those results, we attempted to propose fishery management strategy to harvest fisheries resources continuously. Catch obtained from field surveys comprised total 78 species, which accounted for 53 species of fish, 20 species of crustacean, 4 species of cephalopod and one of polychaete. As to species composition in weight, it showed that there was 88.5% for pisces, 9.0% for cephalopoda and 2.5% for crustacea. As to catch specifics by area, there was 36 species (596,891 individual, 456,551g) of pisces, 17 species (35,815 individual, 12,909g) of crustacea and 3 species (2,876 individual, 3,004g) of cephalopoda in Masari area. In Supumri area, there was 41 species (396,898 individual, 281,457g) of pisces, 15 species (16,113 individual, 7,772g) of crustacea and 4 species (6,792 individual, 72,329g) of cephalopoda and one polychaeta (36 individual, 11g). Catch of anchovy by month recorded on high level on June, July, September in both areas. When considering size composition by month, it was found that new populations recruit to these fishing grounds on June and September. Most of bycatch species including hairtail (Trichiurus lepturus), dotted gizzard shad (Konosirus punctatus), conger eel (Leptocephalous), Pacific sandlance (Ammodytes personatus), horse mackerel (Trachurus japonicus) were juvenile, and grass puffer (Takifugu niphobles), Kammal thryssa (Thryssa kammalensis), Japanese sardinella (Sardinella zunasi) were also small in size. As a result, it is considered that gape net with wings fishery which is likely to catch juvenile needs to be set fishing prohibit period for conserving above stocks during the period excluding main fishing periods of anchovy or fisheries management such as expanding mesh size for preventing juvenile catch.