• Journal of Computing Science and Engineering
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• v.8 no.1
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• pp.1-10
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• 2014

The Bacterial Foraging Optimization Algorithm is a swarm intelligence optimization algorithm. This paper first analyzes the chemotaxis, as well as elimination and dispersal operation, based on the basic Bacterial Foraging Optimization Algorithm. The elimination and dispersal operation makes a bacterium which has found or nearly found an optimal position escape away from that position, which greatly affects the convergence speed of the algorithm. In order to avoid this escape, the sphere of action of the elimination and dispersal operation can be altered in accordance with the generations of evolution. Secondly, we put forward an algorithm of an adaptive adjustment of step length we called improved bacterial foraging optimization (IBFO) after making a detailed analysis of the impacts of the step length on the efficiency and accuracy of the algorithm, based on chemotaxis operation. The classic test functions show that the convergence speed and accuracy of the IBFO algorithm is much better than the original algorithm.

• Geomechanics and Engineering
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• v.8 no.6
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• pp.811-828
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• 2015

Proper modelling of the basal resistance terms is key in simulating the motion of fluidized granular flow. In this paper, standard depth-averaged governing equations of granular flow are used together with the classical Coulomb, Voellmy, and velocity dependent friction models (VDFM). A high-resolution modified TVDLF method is implemented to solve the partial differential equations without numerical oscillations. The effects of basal resistance terms on the motion of granular flows such as geometric shape evolution, travel times and final deposits are analyzed. Based on the numerical results, the predictions of the front and rear end positions and developing length of granular flow with Coulomb friction model show excellent agreements with experiment results reported by Hutter et al. (1995), and illustrate the validity of the numerical approach. For the Voellmy model, the higher value of turbulent coefficient than reality may obtain more reasonable predicted runout for the small-scale avalanche or granular flow. The energy exchange laws indicate that VDFM is different from the Coulomb and Voellmy models, although the flow characteristics of both three models fit the measurements and observations very well.

• BMB Reports
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• v.42 no.1
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• pp.28-34
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• 2009

To understand the molecular mechanism underlying proline accumulation in Brassica napus, cDNAs encoding ${\Delta}^1$-pyrroline-5-carboxylate synthetase (BnP5CS), ornithine $\delta$-aminotransferase (BnOAT) and proline dehydrogenase (BnPDH) were isolated and characterized. Southern blot analysis of BnP5CSs in B. napus and its diploid ancestors suggested a gene loss may have occurred during evolution. The expression of BnP5CS1 and BnP5CS2 was induced, while the expression of BnPDH was inhibited under salt stress, ABA treatment and dehydration, prior to proline accumulation. The upregulation of BnOAT expression was only detected during prolonged severe osmotic stress. Our results indicate that stress-induced proline accumulation in B. napus results from the reciprocal action of activated biosynthesis and inhibited proline degradation. Whether the ornithine pathway is activated depends on the severity of stress. During development, proline content was high in reproductive organs and was accompanied by markedly high expression of BnP5CS and BnPDH, suggesting possible roles of proline during flower development.

• Steel and Composite Structures
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• v.21 no.3
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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.

• Journal of Information Processing Systems
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• v.16 no.2
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• pp.460-477
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• 2020

As one of the most significant challenges in the virtual data center, the virtual data center embedding has attracted extensive attention from researchers. The existing research works mainly focus on how to design algorithms to increase operating revenue. However, they ignore the energy consumption issue of the physical data center in virtual data center embedding. In this paper, we focus on studying the energy-aware virtual data center embedding problem. Specifically, we first propose an energy consumption model. It includes the energy consumption models of the virtual machine node and the virtual switch node, aiming to quantitatively measure the energy consumption in virtual data center embedding. Based on such a model, we propose two algorithms regarding virtual data center embedding: one is heuristic, and the other is based on particle swarm optimization. The second algorithm provides a better solution to virtual data center embedding by leveraging the evolution process of particle swarm optimization. Finally, experiment results show that our proposed algorithms can effectively save energy while guaranteeing the embedding success rate.

• Animal Systematics, Evolution and Diversity
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• v.6 no.1
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• pp.57-70
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• 1990

한국산 털진드기 종을 다룬 모든 문헌을 조사 정리한 결과 총 43종이 보고되었는데, 그중 Salchia brennani ventralis 는 오동정한 것으로 W. comataxila 이었고 Shunsennia gracilis 는 S. hertigi 의 동종이명일 가능성이있으나 문헌상으로는 확인할 수 없었다. Leptotromibidium intermedium 의 경우 문헌상의 근거가 전혀 없어 국내 서식종으로 인정할 수 없었다. 필자가 직접 표본을 조사하여 확인할 수 있었던 종은 모두 17 종이었는데 그 가운데 Leptotromibidium akamushi 는 L.zutum 의 , L.miyajimai 는 L.orientale 의 오동정이었다. 결국 한국산 털진드기류는 모두 2과 , 12속, 39종이 된다. 이 중 2 종은 조류에 , 7종은 박쥐에, 그리고 29종은 설치류에 각각 기생하는 종이고 1종은 조류와 포유류에 공동기생하는 종이다. 현재 한국산 털진드기를 동정하는데 이용할 수 있는 검색표로는 29종을 아룬 Southwick (1968) 의것이 있을 뿐이고, 우리나라와 동물상이 유사하나 일본 종에 대한 검색표도 우리나라 토착종 21종이 들어 있지 않아 도움이 되지 않는다. 뿐만 아니라, 기존 검색표는 다리의 강모식(leg setal formula) 이나 촉수의 강모식( palpal setal formula)등 관찰하기 어려운 형질을 많이 사용하고 있어서 동정에 어려움이 많았다. 이에 필자는 현재까지 한국 종으로 정리된 총 39종에 대한 검색표를 만들었는데, 관찰이 용이하면서도 변이가 적은 형질을 최대한 사용하였고 특히 종 특징을 잘 나타내는 배판(scutum)의 형질을 주로 사용하였다. 실용성이 보다 큰 도식형 검색표( pictorial key)도 함께 만들었는데 원저자들의 도표에서 배판(scutum)을 그대로 전사하여 종 간 비교를 용이하게 하였다.

• Animal Systematics, Evolution and Diversity
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• no.nspc3
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• pp.45-58
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• 1992

Tetranychoid mites found from Korea until now are 42 species belonging to 12 genera, 2 families as follows: 1 Bryobia japonica Ehara et Yamada, 2. B. praetiosa Koch, 3. B. rubrioculus(Scheuten), 4. Petrobia latens(Muller), 5. Aponychus corpuzae Rimando, 6. A firmianae(Ma et Yuan). 7. Panonychus citri(McGregor), 8. P. ulmi(Koch), 9. Eotetranychus carpini Oudemans, 10. E. hicoriae(McGregor), 11. E. populi(Koch), 12. E. rubiphilus (Reck), 13. E. sexmaculatus (Riley), 14. E. smithi Pritchard et Baker, 15. E. tiliarium (Hermann), 16. E. uchidai Ehara, 17. Schizotetranychus bambusae Reck, 18. S. celarius(Banks), 19. S. leguminosus Ehara, 20. Oligonychus aceris(Shimer), 21. O. clavatus(Ehara), 22. O. hondoensis(Ehara), 23. O. ilicis(McGregor), 24. O. karamatus(Ehara), 25. O. orthius Rimando, 26. O. peridtus Pritchard et Baker, 27. O. shinkajii Ehara, 28. O. pustulosus (Ehara), 29. O. ununguis(Jacobi), 30. O. sp. 31. Tetranychus kanzawai Kishida, 32. T. phaselus Ehara, 33. T. truncatus Ehara, 34. T. urticae Koch, 35. T. vienensis Zacher, 36. Aegyptobia nothus Pritchard et Baker, 37. Pentamerismus taxi (Haller), 38. P. oregonensis McGregor, 39. Brevipalpus californicus(Banks), 40. B. lewisi McGregor, 41. B. obovatus Donnadieu, 42. Tenuipalpus zhizhilashviliae Reck. On the above species, a taxanomic key was made and ecological data including distribution and host plant are presented in this paper.

• Animal Systematics, Evolution and Diversity
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• v.31 no.1
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• pp.31-41
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• 2015

A new species of the genus Farranula Wilson, 1942 (Cyclopoida, Corycaeidae) is described based on both sexes collected off Chuuk Island in Micronesia (West Central Pacific). The new species F. dahlae differs from its close congener F. gibbula (Giesbrecht, 1891) in the following combination of characters in both sexes: body length is longer, length to width ratio of caudal rami is larger, basal element of maxilliped is distinctly longer, and terminal spine to distal segment ratio of P4 is smaller; while in females, lateral margins of fourth pedigerous somite are extended to mid-region of second urosomal somite, maximum width of the second urosomal somite is located at middle region in dorsal and lateral views, and length ratio of caudal seta III to seta V is much larger; and in males, sharply contracted portion of second somite is located at two-thirds distance from anterior margin. Some additional morphological details of F. gibbula are given and a key to species of the genus Farranula is provided.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.11
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• pp.3751-3774
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• 2014

With the rapid development of wireless communication, the confliction between the scarce frequency resources and the low spectral efficiency caused by the stationary spectrum sharing strategies seriously restricts the evolution of the future mobile communication. For this purpose, cognitive radio (CR) emerges as one of the most promising inventions which can overcome the spectrum shortage. As the key technology and main objective of CR, spectrum sharing can make full use of the limited spectrum, alleviate the scarcity of frequency resources and improve the system utilities, playing thereby an important role in improving the system performance of cognitive radio networks (CRNs). In this survey, the spectrum sharing in CRNs is discussed in terms of the sharing process, mainstream sharing technologies and spectrum sharing models. In particular, comparisons of different spectrum sharing strategies are concluded, as well as that of different spectrum sensing schemes in sharing procedure. Moreover, some application examples of the spectrum sharing in CRNs, such as smart grid, public safety, cellular network and medical body area networks are also introduced. In addition, our previous related works are presented and the open research issues in the field of spectrum sharing are stated as well.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.323-331
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• 2015

Zirconium alloys are widely used in nuclear reactors as structural materials. During the operation, they are exposed to fast neutrons. Ion irradiation is used to simulate the damage introduced by neutron irradiation. In this article, we briefly review the neutron irradiation damage of zirconium alloys, then summarize the effect of ion irradiation on microstructural evolution, mechanical and corrosion properties, and their relationships. The microstructure components consist of dislocation loops, second phase precipitates, and gas bubbles. The microstructure parameters are also included such as domain size and microstrain determined by X-ray diffraction and the S-parameter determined by positron annihilation. Understanding the relationships of microstructure and properties is necessary for developing new advanced materials with higher irradiation tolerance.