• Title/Summary/Keyword: Early hybrid

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Efficient simulation method for a gas inflow to the central molecular zone

  • Shin, Jihye;Kim, Sungsoo S.;Baba, Junichi;Saitoh, Takayuki R.;Chun, Kyungwon;Hozumi, Shunsuke
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.59.1-59.1
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    • 2015
  • We present hydrodynamic simulations of gas clouds that inflowing from the disk to a few hundred parsec region of the Milky Way. Realistic Galactic structures are included in our simulations by thousands of multipole expansions that describe 6.4 million stellar particles of a self-consistent Galaxy simulation (Baba, Saitoh & Wada, in prep.). We find that a hybrid multipole expansion model with two different basis sets and a thick disk correction well reproduces the overall structures of the Milky Way. We find that the nuclear ring evolves into 240 pc at T~1500 Myr, regardless of the initial size. For most of simulation runs, gas inflow rate to the nuclear region is equilibrated as ~0.02 Msun/yr, and thus accumulated gas mass and star formation activity is stabilized as $6{\times}10^7Msun$ and ~0.02M/yr, respectively. These stabilized values are in a good agreement with estimations for the CMZ. The nuclear ring is off-centered to the Galactic center by the lopsided central mass distribution of the Galaxy model, and thus an asymmetric mass distribution is arose accordingly. The lopsidedness also leads the nuclear ring to be tilted to the Galactic plane and to precess along the Galaxy rotation. In early evolutionary stage when gas clouds start to inflow and form the nuclear ring, the z-directional oscillations of the gas clouds results in the twisted, infinity-shaped nuclear ring. Since the infinity-shaped feature is transient only for first 100 Myr, the current infinity-shape observed in the CMZ may indicate that the CMZ forms quite recently.

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Vibration Control for a Single Degree of Freedom Structure Using Active Friction Slip Braces (능동 조임 마찰 가새로 보강한 단자유도 구조물의 응답)

  • Lee, Jin-Ho;Zekai, Akbay;Kim, Jung-Gil;Oh, Sang-Gyun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.10 no.1
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    • pp.131-138
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    • 2006
  • Structural bracing concept equipped with a new and efficient friction based energy dissipation device is referred to Friction SliP Brace (FSB) where the behavior of the brace components is elastic until the axial resistant force in the brace exceeds the friction force developed at the frictional interface of the device. In this study, the FSB concept is modified and new type of hybrid energy dissipation device, the Active Friction SliP Braces (AFSB), is described. The FSB is by far improved in the AFSB by inclusion of an active clamping mechanism on the friction interface. The clamping action regulated by the developed algorithm is altered during the response of the building. The results indicate that the action of dissipating vibrational energy in the AFSB impacts on the response at later cycles by keeping the drift amplitudes at much lower levels, revealing overshooting problem due to its early slippage. Providing predetermined constant incremental strengths to the building by AFSB medium improves response by reducing drift amplitudes and base shear under small and medium amplitude ground accelerations.

A New High Yielding Gerbera 'Azalin' with Pink, Green Disc Floret and Semi-double for Cut-flower (녹심의 다수성 분홍색 반겹꽃 절화용 거베라 신품종 'Azalin')

  • Park, Sang-Kun;Lim, Jin-Hee;Choi, Seong-Youl;Shin, Hak-Ki;Lee, Jung-Soo
    • Horticultural Science & Technology
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    • v.30 no.1
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    • pp.97-100
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    • 2012
  • A new gerbera (Gerbera hybrid Hort.) 'Azalin' was bred by the National Institute of Horticultural & Herbal Science in 2009. 'Basic' and 'Rosabella' which had pink color and semi-double flower were crossed in 2006. After investigation of the characteristics for four years (from 2006 to 2009), it was selected specially for the use of cut flower. The 'Azalin' had brilliant pink color (RHS RP68A) with green disc center. The flower was semi-double and 10.6 cm in diameter. It had a thick peduncle of which upper and lower width were 3.7 mm and 5.5 mm, respectively. The average days to first flowering of 'Azalin', 88.5 days, was approximately 8.7 days earlier than the control cultivar. And its average yield, 55.8 stems per plant, was also 7.4 stems per plants more than the control cultivar.

Long Term Follow-up of Children with Facial Asymmetry: A Case Report (안면 비대칭을 보이는 아이의 장기 추적 관찰 : 증례보고)

  • Oh, Yoonjeong;Oh, Sohee
    • Journal of the korean academy of Pediatric Dentistry
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    • v.45 no.3
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    • pp.378-385
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    • 2018
  • Mandibular fractures occur with high incidence among various fractures in maxillofacial region in children. Jaw fractures in children should be approached differently than in adults because bone growth continues throughout childhood. As far as displacement of the fragment is not severe, or if it is condyle that is fractured, closed reduction and additional intermaxillary fixation can be considered. Functional exercise is also required to prevent ankylosis of temporomandibular joint. Several complications, particularly malocclusion and facial asymmetry due to growth disturbances, can occur after condylar fractures. If growth disturbances take place after mandibular fractures, catch-up growth may occur in some patients, thus, periodic observation is necessary. In case of persistent growth disturbances, functional devices may be used to prevent severe facial asymmetry. This case report describes the long-term follow-up of two patients with facial asymmetry after mandibular fracture.

Impact of Shading Net Color on Phytochemical Contents in Two Chili Pepper Hybrids Cultivated Under Greenhouse Conditions

  • Nagy, Zsuzsa;Daood, Hussein;Nemenyi, Andars;Ambrozy, Zsuzsanna;Pek, Zoltan;Helyes, Lajos
    • Horticultural Science & Technology
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    • v.35 no.4
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    • pp.418-430
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    • 2017
  • The objective of this study was to understand the combined effect of shading treatment and harvest time on pungency, ascorbic acid content, market-quality pepper yield, and photosynthetic activity in a yellow 'Star Flame' and 'Fire Flame' F1 hybrid pepper cultivar (Capsicum annuum). Plants were cultivated in a greenhouse under white, red, and green shading nets and compared to those grown under unshaded control conditions. The ascorbic acid and pungency parameters were analyzed by high-performance liquid chromatographic methods. Ascorbic acid, a compound of high nutritive value in pepper, was highest in fruits gathered during the first summer harvest in both hybrids. The ascorbic acid content was found to be further increased in fruits from plants grown under white net shading in both 'Star Flame' and 'Fire Flame'. Total capsaicinoid contents in 'Star Flame' were influenced by the interaction of shading treatment and harvest time (p = 0.004), with the lowest amounts ($241.2-251.5mg{\cdot}kg^{-1}$ fresh weight) resulting from white and red shading treatments at the early autumn harvest. In 'Fire Flame', both shading treatment (p = 0.009) and harvest time (p < 0.001) affected total capsaicinoid contents. We observed significantly higher total capsaicinoid contents in control fruits compared to that resulting from red and green shading treatments at the second harvest, and that resulting from red shading treatment at the third harvest. Analysis of photosynthetic activity revealed a significant and negative correlation between Fv/Fm values and total capsaicinoid contents in both hybrids (p < 0.001). Based on the obtained results, the harvest of peppers during summer should be promoted to produce fruits with high pungency.

An XML Query Optimization Technique by Signature based Block Traversing (시그니처 기반 블록 탐색을 통한 XML 질의 최적화 기법)

  • Park, Sang-Won;Park, Dong-Ju;Jeong, Tae-Seon;Kim, Hyeong-Ju
    • Journal of KIISE:Databases
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    • v.29 no.1
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    • pp.79-88
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    • 2002
  • Data on the Internet are usually represented and transfered as XML. the XML data is represented as a tree and therefore, object repositories are well-suited to store and query them due to their modeling power. XML queries are represented as regular path expressions and evaluated by traversing each object of the tree in object repositories. Several indexes are proposed to fast evaluate regular path expressions. However, in some cases they may not cover all possible paths because they require a great amount of disk space. In order to efficiently evaluate the queries in such cases, we propose an optimized traversing which combines the signature method and block traversing. The signature approach shrink the search space by using the signature information attached to each object, which hints the existence of a certain label in the sub-tree. The block traversing reduces disk I/O by early evaluating the reachable objects in a page. We conducted diverse experiments to show that the hybrid approach achieves a better performance than the other naive ones.

A Study of Ethnic Images Found in Modern Sports Fashion (현대 스포츠패션에 나타난 에스닉 이미지 연구)

  • Kim Eun-Kyoung;Chae Keum-Seok
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.7 s.155
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    • pp.1054-1065
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    • 2006
  • This study aims to provide basic data conducive to developing popular and international products by analyzing the mechanism, factors and design of ethnic sports fashion incorporating ethnicity and sports sense that may satisfy the physical and psychological needs of modern humans who tend to seek 'well- being'. The methodology includes literature reviews and positivist study, and visual materials include domestic and foreign fashion magazines, newspapers, fashion journals, ad photos, collection photos, and internet that cover colors, materials, detailed sports fashion design that are considered to have an ethnic image. Its scope is limited to the period from 2000 through 2005 S/S. The results of study are as follows: First, sports fashions through incorporation of sports emotion and fashion, mixes and matches existing formal wear, casual wear, or leisure wear with sportswear, or introduces and utilizes materials, details, accessories, or image from sportswear. Second, 1) from the changes by year in sports fashion, ethnic images were strongly expressed by the influence of naturalism in the early 1990s, and functional sports fashion has been fused with ethnic image with functionalism becoming stronger and wellbeing trend expanding from the mid 1990s through 2000s. 2) The cause of ethnic image in sports fashion included hybrid, multi-culturalism, and naturalism. Third, the ethnic images revealed in the sports fashion designs of Prada, Louis Vuitton, Gucci, and Y3 are simple and unique based on functionality and activism.

A Study on APC Subsidy Policies to Encourage OA Publishing (오픈액세스 확산을 위한 APC 지원 정책에 관한 연구)

  • Shin, Eun-Ja
    • Journal of the Korean Society for information Management
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    • v.31 no.3
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    • pp.249-270
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    • 2014
  • OA journal publishing has steadily increased its relative share of all scholarly journal articles by about 20%-30%. The 'Gold' OA, often preferred by readers, refers to journal articles which are more widely available through the journal's web site immediately. This study analyzed funder and university's policy for paying APCs in implementing a Gold OA. In recent years there have been a number of attempts in the UK and Europe to stimulate more systematic arrangements for paying APCs, leading funders have clearly established arrangements in place. Also OA fund made by major universities in North America provides publisher with APCs. On the other hand, it is still in early stages in paying with gold OA requirements from Korean funders and universities. The funders have a 'Green' OA policy, such as upload the article accepted version to their online platform. Although it varies by field, many Korean authors are publishing in international journals. Their articles' impacts would rise when they are published as gold OA. Therefore, funders and universities need to pay attention to gold OA publishing and set up subsidies for APCs which are required by OA or hybrid journal publishers.

E-Business and Simulation

  • Park, Sung-Joo
    • Proceedings of the Korea Society for Simulation Conference
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    • 2001.10a
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    • pp.9-10
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    • 2001
  • Simulation has been evolved with the advance of computer and technique of modeling application systems. Early simulations were numerical analysis of engineering models known as continuous simulation, analysis of random events using various random number generators thus named as Monte Carlo simulation, iud analysis o(\\\\`queues which are prevalent in many real world systems including manufacturing, transportation, telecommunication. Discrete-event simulation has been used far modeling and analyzing the systems with waiting lines and inefficient delays. These simulations, either discrete-event, continuous, or hybrid, have played a key role in industrial age by helping to design and implement the efficient real world systems. In the information age which has been brought up by the advent of Internet, e-business has emerged. E-business, any business using Internet, can be characterized by the network of extended enterprises---extended supply and demand chains. The extension of value chains spans far reaching scope in business functions and space globally. It also extends to the individual customer, customer preferences and behaviors, to find the best service and product fit for each individual---mass customization. Simulation should also play a key role in analyzing and evaluating the various phenomena of e-business where the phenomena can be characterized by dynamics, uncertainty, and complexity. In this tutorial, applications of simulation to e-business phenomena will be explained and illustrated. Examples are the dynamics of new economy, analysis of e-business processes, virtual manufacturing system, digital divide phenomena, etc. Partly influenced by e-business, a new trend of simulation has emerged called agent-based simulation, Agent-based simulation is a technique of simulation using software agent that have autonomy and proactivity which are useful in analyzing and integrating numerous individual customer's behavior. One particular form of agent-based simulation is swarm. This tutorial concludes with the illustration of swarm or swarm Intelligence applied to various e-business applications, and future directions and implications of this new trend of simulation.

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Molecular Phylogeny of Korean Loaches Inferred from Mitochondrial DNA Cytochrome b Sequences (Mitochondrial Cytochrome b gene의 분석에 의한 한국산 미꾸리과 어류(Cobitidae)의 계통)

  • Kim, So-Young;Kim, Ik-Soo;Jahng, Kwang-Yeop;Chang, Mi-Hee
    • Korean Journal of Ichthyology
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    • v.12 no.4
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    • pp.223-229
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    • 2000
  • Phylogenetic relationships between 8 species Korean loaches (Cobitidae) were investigated by comparing mitochondrial cytochrome b gene sequences. However our results are in accordance with finding observed using other morphological studies, new interesting interspecific variation in Korean loaches were found. Orthrias and Lefua appeared to be paraphyletic in Cobitidae observed. Their sequence divergence value was agreed with interfamilic sequence divergences between Cobitidae and Cyprinidae ranged from 0.184 to 0.272. Otherwise, the present results support that two species of Iksookimia and Cobitis melanoleuca were early diverged respectively. And another remarkable result was sequence divergence between Misgurnus anguillicaudatus from China and M. anguillicaudatus from Yongdok, Korea. That was 0.099, which was interspecific value. Also the phylogenetic location of some Iksookimia species was suggested as the cobitid intergeneric hybrid origin.

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