• Title/Summary/Keyword: evolution patterns

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Investigation of Korean Precipitation Variability using EOFs and Cyclostationary EOFs (EOF와 CSEOF를 이용한 한반도 강수의 변동성 분석)

  • Kim, Gwang-Seob;Sun, Ming-Dong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1260-1264
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    • 2009
  • Precipitation time series is a mixture of complicate fluctuation and changes. The monthly precipitation data of 61 stations during 36 years (1973-2008) in Korea are comprehensively analyzed using the EOFs technique and CSEOFs technique respectively. The main motivation for employing this technique in the present study is to investigate the physical processes associated with the evolution of the precipitation from observation data. The twenty-five leading EOF modes account for 98.05% of the total monthly variance, and the first two modes account for 83.68% of total variation. The first mode exhibits traditional spatial pattern with annual cycle of corresponding PC time series and second mode shows strong North South gradient. In CSEOF analysis, the twenty-five leading CSEOF modes account for 98.58% of the total monthly variance, and the first two modes account for 78.69% of total variation, these first two patterns' spatial distribution show monthly spatial variation. The corresponding mode's PC time series reveals the annual cycle on a monthly time scale and long-term fluctuation and first mode's PC time series shows increasing linear trend which represents that spatial and temporal variability of first mode pattern has strengthened. Compared with the EOFs analysis, the CSEOFs analysis preferably exhibits the spatial distribution and temporal evolution characteristics and variability of Korean historical precipitation.

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Microstructural evolution of rheocast Al-6.2wt.%Si alloy with isothermal stirring (Al-6.2wt.%Si 합금의 등온교반시간에 따른 미세조직변화)

  • Lee, Jung-Ill;Park, Ji-Ho;Kim, Gyeung-Ho;Lee, Ho-In
    • Journal of Korea Foundry Society
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    • v.15 no.5
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    • pp.514-522
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    • 1995
  • The microstructural evolution with isothermal stirring during semi-solid state processing of hypoeutectic Al-6.2wt%Si alloy was studied. Substructure of the individual primary solid particle in the slurry was investigated through transmission electron microscopy(TEM). Formation of subgrain boundaries on the rheocast Al-6.2wt%Si alloy is observed and the misorientation between the grains is shown typically under 2 degrees by analyzing selected area diffraction (SAD) and convergent beam electron diffraction (CBED) patterns. The existence of high angle grain boundaries are also observed in the alloy. Based upon these observations, mechanisms for the primary particles fragmentation are considered. With isothermal stirring, the dislocation density increases, and the evolution of dislocation cell structure takes place, which is interpreted as a process of achieving uniform deformation by dynamic recovery under applied shear stress.

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Knowledge sharing in the evolution of Internet portals (인터넷 포털 진화에서의 지식공유)

  • Park, Seung-Bong;Kim, Jae-Young;Han, Jae-Min;Seo, Min-Kyo
    • Proceedings of the Korea Database Society Conference
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    • 2008.05a
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    • pp.13-30
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    • 2008
  • The objective of this study is to explore a knowledge sharing typology for Internet portals based on knowledge-based view of firm. Furthermore, we provide insights into how the evolution of Internet portals takes place by describing user behavior of knowledge sharing. For doing this, we first present a typology of knowledge sharing based on the two dimensions such as knowledge donation and knowledge collection. Then we conduct case study of the Korean major portals to demonstrate a proposed typology. The main finding of the analysis is that three distinctive types of knowledge sharing patterns within portals are distinguished: collaboration, accumulation, and publishing. We conclude that user behavior of knowledge sharing is characterized as guiding factors in evolution process.

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Strategies for Evolution in Neural Networks based on Cellular Automata (셀룰라 오토마타 기반 신경 회로망의 진화를 위한 전략)

  • Jo, Yong-Goon;Lee, Won-Hee;Kang, Hoon
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2193-2196
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    • 1998
  • Cellular automata are dynamical systems in which space and time are discrete, where each cell has a finite number of states and updates its states by interactive rules among the cell-neighborhood. From the characteristics of self-reproduction and self- organization, it is possible to create a neural network which has the specific patterns or structures dynamically. CAM-Brain is a kind of such neural network system which evolves its structure by adopting evolutionary computations like genetic algorithms (GA). In this paper, we suggest the evolution strategies for the structure of neural networks based on cellular automata.

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The Evolution of Drone and Air Defense Technologies: Implications for the Future Battlefield

  • Kim Seung-Hyun
    • International Journal of Advanced Culture Technology
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    • v.12 no.2
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    • pp.286-298
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    • 2024
  • The rapid advancement of drone technology has significantly altered the landscape of modern warfare, presenting both opportunities and challenges for military forces worldwide. As drones become increasingly sophisticated, capable of performing complex missions such as reconnaissance, surveillance, and precision strikes, the development of effective air defense systems has become a critical priority. This study examines the current state of drone and air defense technologies, analyzing their impact on military strategies, tactics, and the future battlefield environment. By exploring the patterns of technological evolution, the limitations of existing air defense systems, and the potential consequences of drone proliferation, this research highlights the need for adaptive, innovative approaches to counter emerging threats. The findings underscore the importance of investing in advanced detection and interception capabilities, developing comprehensive counter-drone doctrines, and fostering international cooperation to address the ethical and legal challenges posed by the military use of drones. As the competition between drone and air defense technologies continues to intensify, policymakers and military leaders must proactively engage in shaping the future of warfare to ensure national security and stability in an increasingly complex world.

Acupuncture: How Might the Mechanisms of Treatment Have Contributed to the Diagnosis of "Patterns" and Pattern-based Treatments - Speculations on the Evolution of Acupuncture as a Therapy. Implications for Researchers

  • Birch, Stephen
    • Journal of Acupuncture Research
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    • v.35 no.2
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    • pp.47-51
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    • 2018
  • Acupuncture is a complex intervention that manifests varied theories, treatment methods, diagnostic methods and diagnostic patterns. Traditionally based systems of acupuncture (TBSAs) often have their own diagnostic approaches and patterns. Despite the wide variety that can be found amongst TBSAs, is it possible that they share a common background in clinical observation and practice? Research has shown that multiple physiological pathways and mechanisms can be triggered by different acupuncture techniques and methods. It is highly likely that clinicians will have observed some of the effects of these responses and used those observations as feedback to help construct the patterns of diagnosis and their associated treatments. This review briefly examines this possibility. Pattern identification will have developed out of a complex interaction of factors that include; theories current at the time of their development, historical theories, personal choices and beliefs, training, practice methods, clinical observations and the natural feedback that comes from observing how things change once the treatment is applied. Researchers investigating TBSAs and pattern identification need to be more explicit about the systems they have investigated in order to understand the biological basis of pattern identification and their treatments.

A Co-Evolutionary Approach for Learning and Structure Search of Neural Networks (공진화에 의한 신경회로망의 구조탐색 및 학습)

  • 이동욱;전효병;심귀보
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1997.10a
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    • pp.111-114
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    • 1997
  • Usually, Evolutionary Algorithms are considered more efficient for optimal system design, However, the performance of the system is determined by fitness function and system environment. In this paper, in order to overcome the limitation of the performance by this factor, we propose a co-evolutionary method that two populations constantly interact and coevolve. In this paper, we apply coevolution to neural network's evolving. So, one population is composed of the structure of neural networks and other population is composed of training patterns. The structure of neural networks evolve to optimal structure and, at the same time, training patterns coevolve to feature patterns. This method prevent the system from the limitation of the performance by random design of neural network structure and inadequate selection of training patterns. In this time neural networks are trained by evolution strategies that are able to apply to the unsupervised learning. And in the coding of neural networks, we propose the method to maintain nonredundancy and character preservingness that are essential factor of genetic coding. We show the validity and the effectiveness of the proposed scheme by applying it to the visual servoing of RV-M2 robot manipulators.

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A Study on Spatial Application of Digital Modulation Patterns - Focusing on generating digital patterns - (디지털 패턴의 생성과 공간적용방법 연구 - 디지털패턴의 생성을 중심으로 -)

  • Park, Jeong-Joo
    • Korean Institute of Interior Design Journal
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    • v.19 no.6
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    • pp.100-111
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    • 2010
  • 'Pattern' is the term that is frequently used in the aspects of history, society, and science. It always appears in the remains or relics of the age of civilization when recording was started, and its evaluation and value differ by time. Patterns in the ancient civilization were symbolic, social, and spatially crucial. However, after the modernization, they were considered to be immoral and unnecessary, so the range of their significance came to reduce. Due to the development of science, ornament patterns lost the limitation of its range of use along with new interpretation of them. Especially with the advent of new scientific theories such as the evolution theory from the biological aspect, quantum mechanics, and super string theory, morphological possibilities more than the human scale perceived by men came to be discovered. Living organisms maintain their lives through patterns, structures, and processes in order to produce a system alive. Among them, patterns are the organization of relations determining the characteristics of the system. The present patterns may correspond to this meaning. The pattern in a space is the matter of how to relate the components after all. In a space, however, there are numerous components mingled with one another. If these tasks are conducted as analogue work, it will take a lot of time and effort. However, if digital media are utilized to perform the tasks like analysis, generation, or fabrication, it will produce a result with higher precision and efficiency. In this sense, parametric modeling is quite useful media. Opening morphological variation, it realizes more possibilities, connects conveniently the relations between complex components composing a space, and helps produce creative patterns.

Incremental Enrichment of Ontologies through Feature-based Pattern Variations (자질별 관계 패턴의 다변화를 통한 온톨로지 확장)

  • Lee, Sheen-Mok;Chang, Du-Seong;Shin, Ji-Ae
    • The KIPS Transactions:PartB
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    • v.15B no.4
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    • pp.365-374
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    • 2008
  • In this paper, we propose a model to enrich an ontology by incrementally extending the relations through variations of patterns. In order to generalize initial patterns, combinations of features are considered as candidate patterns. The candidate patterns are used to extract relations from Wikipedia, which are sorted out according to reliability based on corpus frequency. Selected patterns then are used to extract relations, while extracted relations are again used to extend the patterns of the relation. Through making variations of patterns in incremental enrichment process, the range of pattern selection is broaden and refined, which can increase coverage and accuracy of relations extracted. In the experiments with single-feature based pattern models, we observe that the features of lexical, headword, and hypernym provide reliable information, while POS and syntactic features provide general information that is useful for enrichment of relations. Based on observations on the feature types that are appropriate for each syntactic unit type, we propose a pattern model based on the composition of features as our ongoing work.

Exploring the Applicability of Grain Size Trend Analysis to Understanding the Morphological Responses of the Deltaic Barrier Islands in the Nakdong River (낙동강 삼각주연안 사주섬의 지형변화에 대한 입도경향 분석의 활용도 탐색)

  • Kim, Sung-Hwan;Rhew, Ho-Sahng
    • Journal of the Korean association of regional geographers
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    • v.13 no.2
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    • pp.119-128
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    • 2007
  • Grain-size trend analysis is the methodology to obtain the net sediment transport pattern from the spatial trends of grain size parameters. It has the potentials to be an effective tool to address the morphological changes of the deltaic barrier islands in the Nakdoog River once we make sure net transport patterns inferred from grain size trend analysis represent the morphological evolution patterns. This research aims to investigate the applicability of the net transport patterns obtained by 'transport vector', proposed by Gao and Collins(1992), to understanding the morphological changes of the Nakdong River deltaic barrier islands. The results indicate that the net transport directions are overall in concordance with the morphological evolution patterns; however, the level of concordance is low in the island with fast growing rate. The reasons may be match or mismatch of temporal scales involved between processes represented by net transport patterns and morphological change analyzed or the rate of morphological change. Consequently, the application of grain size trend analysis in analyzing the morphological changes of deltaic barrier islands requires the careful consideration of temporal scales involved.

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