• Title/Summary/Keyword: key evolution

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First Zoeas of Nursia rhomboidalis and Pyrhila carinata (Crustacea: Decapoda: Leucosiidae) with a Key to the Known Zoeas of Ten Leucosiid Species from Korean Waters

  • Lee, Seok Hyun;Ko, Hyun Sook
    • Animal Systematics, Evolution and Diversity
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    • v.33 no.4
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    • pp.228-234
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    • 2017
  • The first zoeas of Nursia rhomboidalis and Pyrhila carinata were obtained from laboratory condition. They are described and illustrated for the first time. Morphological comparison with those of other Korean described species of the family Leucosiidae reveals that the zoea of N. rhomboidalis is very similar to those of Myra fugax and Arcania undecimspinosa based on characteristics of the carapace spines length, the antenna morphology, the maxilla endopod setation, and the telson, whereas, the zoea of Py. carinata coincides well with those of Philyra kanekoi and Pyrhila pisum based on characteristics of the carapace spines length, the antenna morphology, the maxilla endopod setation, and the telson. Furthermore, we find that at least two groups of zoeas exist in the Korean species of the subfamily Ebaliinae. A provisional key to the known zoeas of ten leucosiid species from Korean waters is provided.

Larval Development of Oregonia gracilis (Crustacea: Decapoda: Majoidea: Oregoniidae) with a Key to the Known Oregoniid Zoeae from the Northern Pacific

  • Oh, Seong-Mi;Ko, Hyun-Sook
    • Animal Systematics, Evolution and Diversity
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    • v.26 no.1
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    • pp.1-9
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    • 2010
  • The larvae of Oregonia gracilis are described, illustrated and compared with those of other known species of the Oregoniidae. The first zoea of O. gracilis of the present study is somewhat different from that of Hart (1960) especially in having a basis and an endopod of the first maxilliped with 2, 2, 3, 3 and 3, 2, 1, 2, 5 setations, respectively and an endopod of the second maxilliped with 1, 1, 5 setation. It is found the Oregoniidae must be a homogeneous group based on the zoeal morphology. A provisional key for the identification of the known zoeae of the Oregoniidae from the northern Pacific is provided.

Taxonomic Study of Genus Cyclosalpa (Thaliacea: Salpida: Salpidae) from Korea

  • Kim, Sunwoo;Won, Jung-Hye;Kim, Chang-Bae
    • Animal Systematics, Evolution and Diversity
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    • v.28 no.4
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    • pp.261-268
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    • 2012
  • Aggregate and solitary zooids of salps were collected from April 2001 to June 2009. By the analyses based on the morphological characteristics, four species in the genus Cyclosalpa of the subfamily Cyclosalpinae are identified as new records in Korean waters: Cyclosalpa affinis (Chamisso, 1819), Cyclosalpa bakeri Ritter, 1905, Cyclosalpa sewelli Metcalf, 1927, and Cyclosalpa polae Sigl, 1912. These species are re-described with illustrations and photographs in this study. In addition, a key to species of the genus Cyclosalpa in Korean waters and a key to the life cycles of Salpida are provided. As a result of this study twelve species in the Salpidae have been reported from Korea until now.

A Review of Key Issues and Challenges for Sustainable Food Logistics Management

  • Boldbaatar, Tumenjargal;Yoon, Dae Gwun;Sin, Ho Sig
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2014.10a
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    • pp.72-74
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    • 2014
  • The need to further improve food quality and reduce food waste leads to increased attention for the development of Food Supply Chain Management (FSCM) which considers intrinsic characteristics of food supply chains besides traditional supply chain management (SCM) objectives such as cost and responsiveness. Growing consciousness of society towards sustainable development brings additional objectives to the food supply chains and the fast evolution of sustainable development results in the development of a new fast-growing concept: Sustainable Food Supply Chain Management (SFSCM). In response to these developments, researchers have developed various decision support tools that can be used for handling progressively increasing complexity along the alteration process from SCM to FSCM and now to SFSCM. This study reviewed literature on sustainable food logistics management to identify logistical key issues and relevant challenges. The evaluation of the reviewed papers shows that towards obtaining sustainability together with considering intrinsic characteristics of food supply chains, there is a gap between the needs of the practice and the current available method.

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Fatigue performance assessment of welded joints using the infrared thermography

  • Fan, J.L.;Guo, X.L.;Wu, C.W.
    • Structural Engineering and Mechanics
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    • v.44 no.4
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    • pp.417-429
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    • 2012
  • Taking the superficial temperature increment as the major fatigue damage indicator, the infrared thermography was used to predict fatigue parameters (fatigue strength and S-N curve) of welded joints subjected to fatigue loading with a high mean stress, showing good predictions. The fatigue damage status, related to safety evaluation, was tightly correlated with the temperature field evolution of the hot-spot zone on the specimen surface. An energetic damage model, based on the energy accumulation, was developed to evaluate the residual fatigue life of the welded specimens undergoing cyclic loading, and a good agreement was presented. It is concluded that the infrared thermography can not only well predict the fatigue behavior of welded joints, but also can play an important role in health detection of structures subjected to mechanical loading.

Notes on the Korean species of the Genus Streblocera (Insecta: Hymenoptera: Braconidae) with Description of a New Species and a Key to Korean Species (한국산 Streblocera 속 (벌 목: 고치벌 과)의 추가종 기록 및 검색표)

  • Ser;Deok-Seo Ku
    • Animal Systematics, Evolution and Diversity
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    • v.14 no.4
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    • pp.319-325
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    • 1998
  • A new species Streblocera planispina sp. nov. is described from Korea. S. macroscapa Ruthe and S. dentiscapa Belokobylskij are recorded for the first time from Korea. A key to Korean species of Streblocera is given.

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A Taxonomic Review of the Genus Athalia (Hymenoptera: Tenthredinidae: Athaliinae) from South Korea

  • Park, Bia;Choi, Jin-Kyung;Wei, Meicai;Lee, Jong-Wook
    • Animal Systematics, Evolution and Diversity
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    • v.33 no.2
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    • pp.100-111
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    • 2017
  • The species of the genus Athalia Leach from South Korea are reviewed. Six species are listed, one of which is a new record from South Korea (Athalia tanaoserrula Chu and Wang). In South Korean Athalia, we were not able to find any specimens of A. kashmirensis Benson, while many specimens identified as such were a misidentifications of A. tanaoserrula. Therefore, we think that A. kashmirensis should be excluded from the faunal list of South Korea. A key to the species of South Korean Athalia, diagnosis, photographs of the diagnostic characters, distribution and recorded hosts for each species are also provided.

Mechanistic representation of the grading-dependent aggregates resiliency using stress transmission column

  • Sun, Yifei;Wang, Zhongtao;Gao, Yufeng
    • Geomechanics and Engineering
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    • v.17 no.4
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    • pp.405-411
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    • 2019
  • A significant influence of the particle size distribution on the resilient behaviour of granular aggregates was usually observed in laboratory tests. However, the mechanisms underlying this phenomenon were rarely reached. In this study, a mechanistic model considering particle breakage is proposed. It is found to be the combined effects of the coefficient of uniformity and the size range between maximum and minimum particle sizes that influences the resilient modulus of granular aggregates. The resilient modulus is found to undergo reduction with evolution of particle breakage by shifting the initial particle size distribution to a broader one.

Anomalous Propagation Characteristics of an Airy Beam in Nonlocal Nonlinear Medium

  • Wu, Yun-Long;Ye, Qin;Shao, Li
    • Current Optics and Photonics
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    • v.5 no.2
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    • pp.191-197
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    • 2021
  • The anomalous propagation characteristics of a single Airy beam in nonlocal nonlinear medium are investigated by utilizing the split-step Fourier-transform method. We show that besides the normal straight propagation trajectory, the breathing solitons formed by the interaction between Airy beam and nonlocal nonlinear medium can propagate along the sinusoidal trajectory, and the anomalous trajectory can be modulated arbitrarily by altering the initial amplitude and the nonlocal nonlinear coefficient. In addition, the initial amplitude and the nonlocal nonlinear coefficient can have inverse impacts on the formation and transformation of the equilibrium state of spatial solitons, when the two parameters are larger than certain values. Therefore, the reversible transformation of the evolution dynamics of two soliton states can be realized by adjusting those two parameters properly. Finally, it is shown that the propagation properties of the solitons formed by the interaction between Airy beam and nonlocal nonlinear medium can be controlled arbitrarily, by adjusting the distribution factor and nonlocal coefficient.

Low-Complexity Energy Efficient Base Station Cooperation Mechanism in LTE Networks

  • Yu, Peng;Feng, Lei;Li, Zifan;Li, Wenjing;Qiu, Xuesong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.10
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    • pp.3921-3944
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    • 2015
  • Currently Energy-Saving (ES) methods in cellular networks could be improved, as compensation method for irregular Base Station (BS) deployment is not effective, most regional ES algorithm is complex, and performance decline caused by ES action is not evaluated well. To resolve above issues, a low-complexity energy efficient BS cooperation mechanism for Long Time Evolution (LTE) networks is proposed. The mechanism firstly models the ES optimization problem with coverage, resource, power and Quality of Service (QoS) constraints. To resolve the problem with low complexity, it is decomposed into two sub-problems: BS Mode Determination (BMD) problem and User Association Optimization (UAO) problem. To resolve BMD, regional dynamic multi-stage algorithms with BS cooperation pair taking account of load and geographic topology is analyzed. And then a distributed heuristic algorithm guaranteeing user QoS is adopted to resolve UAO. The mechanism is simulated under four LTE scenarios. Comparing to other algorithms, results show that the mechanism can obtain better energy efficiency with acceptable coverage, throughput, and QoS performance.