• 제목/요약/키워드: Immune memory

검색결과 96건 처리시간 0.02초

면역알고리즘의 기억세포를 이용한 제어기 파라메터의 최적화 (Optimization of Controller Parameters using A Memory Cell of Immune Algorithm)

  • 박진현;최영규
    • 대한전기학회논문지:시스템및제어부문D
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    • 제51권8호
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    • pp.344-351
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    • 2002
  • The proposed immune algorithm has an uncomplicated structure and memory-cell mechanism as the optimization algorithm which imitates the principle of humoral immune response. We use the proposed algorithm to solve parameter optimization problems. Up to now, the applications of immune algorithm have been optimization problems with non-varying system parameters. Therefore the usefulness of memory-cell mechanism in immune algorithm is without. This paper proposes the immune algorithm using a memory-cell mechanism which can be the application of system with nonlinear varying parameters. To verified performance of the proposed immune algorithm, the speed control of nonlinear DC motor are performed. The results of Computer simulations represent that the proposed immune algorithm shows a fast convergence speed and a good control performances under the varying system parameters.

DC 모터 파라메터 변동에 대한 면역 알고리즘 제어기 설계 (Immune Algorithm Controller Design of DC Motor with parameters variation)

  • 박진현;전향식;이민중;김현식;최영규
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2002년도 춘계학술대회 및 임시총회
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    • pp.175-178
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    • 2002
  • The proposed immune algorithm has an uncomplicated structure and memory-cell mechanism as the optimization algorithm which imitates the principle of humoral immune response, and has been used as methods to solve parameter optimization problems. Up to now, the applications of immune algorithm have been optimization problems with non-varying system parameters. Therefore, the effect of memory-cell mechanism, which is a merit of immune algorithm, is without. this paper proposes the immune algorithm using a memory-cell mechanism which can be the application of system with nonlinear varying parameters. To verified performance of the proposed immune algorithm, the speed control of nonlinear DC motor are performed. Computer simulation studies show that the proposed immune algorithm has a fast convergence speed and a good control performances under the varying system parameters.

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Epigenetic memory in gene regulation and immune response

  • Kim, Min Young;Lee, Ji Eun;Kim, Lark Kyun;Kim, TaeSoo
    • BMB Reports
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    • 제52권2호
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    • pp.127-132
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    • 2019
  • Cells must fine-tune their gene expression programs for optimal cellular activities in their natural growth conditions. Transcriptional memory, a unique transcriptional response, plays a pivotal role in faster reactivation of genes upon environmental changes, and is facilitated if genes were previously in an active state. Hyper-activation of gene expression by transcriptional memory is critical for cellular differentiation, development, and adaptation. TREM (Transcriptional REpression Memory), a distinct type of transcriptional memory, promoting hyper-repression of unnecessary genes, upon environmental changes has been recently reported. These two transcriptional responses may optimize specific gene expression patterns, in rapidly changing environments. Emerging evidence suggests that they are also critical for immune responses. In addition to memory B and T cells, innate immune cells are transcriptionally hyperactivated by restimulation, with the same or different pathogens known as trained immunity. In this review, we briefly summarize recent progress in chromatin-based regulation of transcriptional memory, and its potential role in immune responses.

Emergent damage pattern recognition using immune network theory

  • Chen, Bo;Zang, Chuanzhi
    • Smart Structures and Systems
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    • 제8권1호
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    • pp.69-92
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    • 2011
  • This paper presents an emergent pattern recognition approach based on the immune network theory and hierarchical clustering algorithms. The immune network allows its components to change and learn patterns by changing the strength of connections between individual components. The presented immune-network-based approach achieves emergent pattern recognition by dynamically generating an internal image for the input data patterns. The members (feature vectors for each data pattern) of the internal image are produced by an immune network model to form a network of antibody memory cells. To classify antibody memory cells to different data patterns, hierarchical clustering algorithms are used to create an antibody memory cell clustering. In addition, evaluation graphs and L method are used to determine the best number of clusters for the antibody memory cell clustering. The presented immune-network-based emergent pattern recognition (INEPR) algorithm can automatically generate an internal image mapping to the input data patterns without the need of specifying the number of patterns in advance. The INEPR algorithm has been tested using a benchmark civil structure. The test results show that the INEPR algorithm is able to recognize new structural damage patterns.

DC 모터 파라메터 변동에 대한 면역 알고리즘 제어기 설계 (Immune Algorithm Controller Design of DC Motor with parameters variation)

  • 박진현;전향식;이민중;김현식;최영규
    • 한국지능시스템학회논문지
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    • 제12권4호
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    • pp.353-360
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    • 2002
  • PID 제어기의 자동 동조 방법이 제어분야에서 많은 연구가 되어 왔으며, 제안된 제어기 또한 PID 제어기 자동동조에 관한 연구이다. 제안된 면역 알고리즘은 인간의 면역 체계를 모방한 최적화 알고리즘으로 기억 세포 메카니즘과 다른 면역 알고리즘에 비하여 덜 복잡한 구조를 가지고 있다. 이렇게 제안된 면역 알고리즘을 PID 제어기의 파라메터를 최적화하는데 사용하고자 한다. 현재까지 면역 알고리즘은 주로 시스템 파라메터의 변동이 없는 최적화 문제에 적용되어왔다. 그러므로 면역 알고리즘에서의 기억세포 메카니즘에 대한 유용성이 없으며, 또한 그에 대한 연구가 미진한 상태이다. 본 연구에서는 비선형 가변 시스템에 기억세포를 사용한 면역 알고리즘을 적용하고자 한다. 제안된 면역 알고리즘의 성능 평가를 위하여 비선형 직류 모터의 속도 제어에 적용하고, 그 결과를 컴퓨터 모의실험을 통하여 제안된 면역 알고리즘이 가변 시스템 파리메에 대하여 빠른 수렴 성능과 좋은 제어 성능을 보임을 보이고자 한다.

기억 세포를 이용한 재고-차량 경로 문제의 인공면역시스템 (An Artificial Immune system using Memory Cell for the Inventory Routing Problem)

  • 양병학
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2008년도 추계학술대회 및 정기총회
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    • pp.236-246
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    • 2008
  • We consider the Inventory Routing problem(IRP) for the vending machine operating system. An artificial immune system(AIS) is introduced to solve the IRP. The IPR is an rolling wave planning. The previous solution of IRP is one of good initial solution of current IRP. We introduce an Artificial Immune system with memory cell (AISM) which store previous solution in memory cell and use an initial solution for current problem. Experiment results shows that AISM reduced calculations time in relatively less demand uncertainty.

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Roles of Virtual Memory T Cells in Diseases

  • Joon Seok;Sung-Dong Cho;Seong Jun Seo;Su-Hyung Park
    • IMMUNE NETWORK
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    • 제23권1호
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    • pp.11.1-11.11
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    • 2023
  • Memory T cells that mediate fast and effective protection against reinfections are usually generated upon recognition on foreign Ags. However, a "memory-like" T-cell population, termed virtual memory T (TVM) cells that acquire a memory phenotype in the absence of foreign Ag, has been reported. Although, like innate cells, TVM cells reportedly play a role in first-line defense to bacterial or viral infections, their protective or pathological roles in immune-related diseases are largely unknown. In this review, we discuss the current understanding of TVM cells, focusing on their distinct characteristics, immunological properties, and roles in various immune-related diseases, such as infections and cancers.

The Roles of CCR7 for the Homing of Memory CD8+ T Cells into Their Survival Niches

  • Hanbyeul Choi;Heonju Song;Yong Woo Jung
    • IMMUNE NETWORK
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    • 제20권3호
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    • pp.20.1-20.15
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    • 2020
  • Memory CD8+ T cells in the immune system are responsible for the removal of external Ags for a long period of time to protect against re-infection. Naïve to memory CD8+ T cell differentiation and memory CD8+ T cell maintenance require many different factors including local environmental factors. Thus, it has been suggested that the migration of memory CD8+ T cells into specific microenvironments alters their longevity and functions. In this review, we have summarized the subsets of memory CD8+ T cells based on their migratory capacities and described the niche hypothesis for their survival. In addition, the basic roles of CCR7 in conjunction with the migration of memory CD8+ T cells and recent understandings of their survival niches have been introduced. Finally, the applications of altering CCR7 signaling have been discussed.

T Cell Immune Responses against SARS-CoV-2 in the With Corona Era

  • Ji-Eun Oh
    • 대한의생명과학회지
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    • 제28권4호
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    • pp.211-222
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    • 2022
  • After more than two years of efforts to end the corona pandemic, a gradual recovery is starting in countries with high vaccination rates. Easing public health policies for a full-fledged post-corona era, such as lifting the mandatory use of outdoor mask and quarantine measures in entry have been considered in Korea. However, the continuous emergence of new variants of SARS-CoV-2 and limitations in vaccine efficacy still remain challenging. Fortunately, T cells and memory T cells, which are key components of adaptive immunity appear to contribute substantially in COVID-19 control. SARS-CoV-2 specific CD4+/CD8+ T cells are induced by natural infection or vaccination, and rapid induction and activation of T cells is mainly associated with viral clearance and attenuated clinical severity. In addition, T cell responses induced by recognition of a wide range of epitopes were minimally affected and conserved against the highly infectious subsets of omicron variants. Polyfunctional SARS-CoV-2 specific T cell memory including stem cell-like memory T cells were also developed in COVID-19 convalescent patients, suggesting long lasting protective T cell immunity. Thus, a robust T-cell immune response appears to serve as a reliable and long-term component of host protection in the context of reduced efficacy of humoral immunity and persistent mutations and/or immune escape.

Cytomegalovirus Infection and Memory T Cell Inflation

  • Kim, Jihye;Kim, A-Reum;Shin, Eui-Cheol
    • IMMUNE NETWORK
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    • 제15권4호
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    • pp.186-190
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    • 2015
  • Cytomegalovirus (CMV) infection in healthy individuals is usually asymptomatic and results in latent infection. CMV reactivation occasionally occurs in healthy individuals according to their immune status over time. T cell responses to CMV are restricted to a limited number of immunodominant epitopes, as compared to responses to other chronic or persistent viruses. This response results in progressive, prolonged expansion of CMV-specific $CD8^+$ T cells, termed 'memory inflation'. The expanded CMV-specific $CD8^+$ T cell population is extraordinarily large and is more prominent in the elderly. CMV-specific $CD8^+$ T cells possess rather similar phenotypic and functional features to those of replicative senescent T cells. In this review, we discuss the general features of CMV-specific inflationary memory T cells and the factors involved in memory inflation.