• Title/Summary/Keyword: adaptive mechanisms

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Seismic Assessment of Plan-irregular Wall Structures using Adaptive Modal Analysis (수정 모드해석방법을 이용한 비대칭 벽식 구조물의 내진성능평가)

  • Ha, Tae-Hyu;Hong, Sung-Gul
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2006.03a
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    • pp.589-596
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    • 2006
  • Torsional behavior of eccentric structures under seismic loading may cause stress and/or strain concentration, which result in the failure of the structures in an unexpected manner. This study propose how to assess the seismic capacity of plan-irregular RC wall structures. The seismic capacities ate expressed in terms of lateral displacement capacity of each wall. The seismic demands for displacement are assessed by so called displacement-based design approach. Those seismic capacity and demands are combined D-R coordinate, which is made up of lateral displacement and rotation angle. To expand these concepts to the inelastic region the adaptive modal analysis method is used. In addition, the failure mechanisms including torsional failure are defined on D-R coordinate. Finally, seismic assessments of two 3-story plan-irregular wall structures ate presented.

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Pain in Animals: Anatomy, Physiology, and Behaviors

  • Youn, Dong-ho;Kim, Tae Wan;Cho, Hee-jung
    • Journal of Veterinary Clinics
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    • v.34 no.5
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    • pp.347-352
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    • 2017
  • Pain, an adaptive but unpleasant sensation, is the most common symptom of numerous diseases in humans and animals. Although animal patients express this symptom frequently, a lack of communication abilities hinders its recognition by veterinary physicians, thereby leading to unsatisfactory management of the symptom. On the other hand, pain itself has its own neurological mechanisms, regardless of the disease that causes it. Thus, a physician may need to know the mechanisms underlying pain development in order to properly manage the symptom in a particular disease. In this review, we attempt to provide a brief introduction to the anatomical, physiological, and neurological basis of pain transmission and sensation. Although most knowledge about these mechanisms comes from studies in humans and laboratory animals, it is generally applicable to pet, farm, or zoo animals. In addition, we summarize pain behavior in several pet, farm, and laboratory animals for its proper identification. This information will help to identify and manage pain, and thus improve welfare, in animals.

Why Should We Consider Potential Roles of Oral Bacteria in the Pathogenesis of Sjögren Syndrome?

  • Sung-Ho Chang;Sung-Hwan Park;Mi-La Cho;Youngnim Choi
    • IMMUNE NETWORK
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    • v.22 no.4
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    • pp.32.1-32.20
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    • 2022
  • Sjögren syndrome (SS) is a chronic autoimmune disorder that primarily targets the salivary and lacrimal glands. The pathology of these exocrine glands is characterized by periductal focal lymphocytic infiltrates, and both T cell-mediated tissue injury and autoantibodies that interfere with the secretion process underlie glandular hypofunction. In addition to these adaptive mechanisms, multiple innate immune pathways are dysregulated, particularly in the salivary gland epithelium. Our understanding of the pathogenetic mechanisms of SS has substantially improved during the past decade. In contrast to viral infection, bacterial infection has never been considered in the pathogenesis of SS. In this review, oral dysbiosis associated with SS and evidence for bacterial infection of the salivary glands in SS were reviewed. In addition, the potential contributions of bacterial infection to innate activation of ductal epithelial cells, plasmacytoid dendritic cells, and B cells and to the breach of tolerance via bystander activation of autoreactive T cells and molecular mimicry were discussed. The added roles of bacteria may extend our understanding of the pathogenetic mechanisms and therapeutic approaches for this autoimmune exocrinopathy.

Adaptive Cross-Device Gait Recognition Using a Mobile Accelerometer

  • Hoang, Thang;Nguyen, Thuc;Luong, Chuyen;Do, Son;Choi, Deokjai
    • Journal of Information Processing Systems
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    • v.9 no.2
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    • pp.333-348
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    • 2013
  • Mobile authentication/identification has grown into a priority issue nowadays because of its existing outdated mechanisms, such as PINs or passwords. In this paper, we introduce gait recognition by using a mobile accelerometer as not only effective but also as an implicit identification model. Unlike previous works, the gait recognition only performs well with a particular mobile specification (e.g., a fixed sampling rate). Our work focuses on constructing a unique adaptive mechanism that could be independently deployed with the specification of mobile devices. To do this, the impact of the sampling rate on the preprocessing steps, such as noise elimination, data segmentation, and feature extraction, is examined in depth. Moreover, the degrees of agreement between the gait features that were extracted from two different mobiles, including both the Average Error Rate (AER) and Intra-class Correlation Coefficients (ICC), are assessed to evaluate the possibility of constructing a device-independent mechanism. We achieved the classification accuracy approximately $91.33{\pm}0.67%$ for both devices, which showed that it is feasible and reliable to construct adaptive cross-device gait recognition on a mobile phone.

The Emerging Role of Natural Killer Cells in Innate and Adaptive Immunity

  • Kim, Eun-Mi;Ko, Chang-Bo;Myung, Pyung-Keun;Cho, Daeho;Choi, Inpyo;Kang, Hyung-Sik
    • IMMUNE NETWORK
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    • v.4 no.4
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    • pp.205-215
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    • 2004
  • In the early host defense system, effector function of natural killer (NK) cells results in natural killing against target cells such as microbe-infected, malignant, and certain allogenic cells without prior stimulation. NK cell cytotoxicity is selectively regulated by homeostatic prevalence between a repertoire of both activating and inhibitory receptors, and the discrimination of untransformed cells is achieved by recognition of major histocompatibility complex (MHC) class I alleles through inhibitory signals. Although it is well known that the bipotential T/NK progenitors are derived from the common precusor, functional mechanisms in terms of the development of NK cells remain to be further investigated. NK cells are mainly involved in innate immunity, but recent studies have been reported that they also play a critical role in adaptive immune responses through interaction with dendritic cells (DC). This interaction will provide effector functions and development of NK cells, and elucidation of its precise mechanism may lead to therapeutic strategies for effective treatment of several immune diseases.

Host Responses from Innate to Adaptive Immunity after Vaccination: Molecular and Cellular Events

  • Kang, Sang-Moo;Compans, Richard W.
    • Molecules and Cells
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    • v.27 no.1
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    • pp.5-14
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    • 2009
  • The availability of effective vaccines has had the most profound positive effect on improving the quality of public health by preventing infectious diseases. Despite many successful vaccines, there are still old and new emerging pathogens against which there is no vaccine available. A better understanding of how vaccines work for providing protection will help to improve current vaccines as well as to develop effective vaccines against pathogens for which we do not have a proper means to control. Recent studies have focused on innate immunity as the first line of host defense and its role in inducing adaptive immunity; such studies have been an intense area of research, which will reveal the immunological mechanisms how vaccines work for protection. Toll-like receptors (TLRs), a family of receptors for pathogen-associated molecular patterns on cells of the innate immune system, play a critical role in detecting and responding to microbial infections. Importantly, the innate immune system modulates the quantity and quality of long-term T and B cell memory and protective immune responses to pathogens. Limited studies suggest that vaccines which mimic natural infection and/or the structure of pathogens seem to be effective in inducing long-term protective immunity. A better understanding of the similarities and differences of the molecular and cellular events in host responses to vaccination and pathogen infection would enable the rationale for design of novel preventive measures against many challenging pathogens.

Research Findings and Implications for Physical Therapy of Spasticity (강직의 최선 지견과 물리치료와의 관련성)

  • Kim, Jong-Man;Choi, Houng-Sik
    • Physical Therapy Korea
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    • v.2 no.2
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    • pp.73-84
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    • 1995
  • Spasticity has been defined as a motor disorder characterised by a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks resulting in hyperexcitability of the stretch reflexes as one component of the upper motor neuron syndrome. Weakness and loss of dexterity, however, are considered to be more disabling to the patient than changes in muscle tone. The discussion includes the important role that alterations in the physiology of motor units, notably changes in firing rates and muscle fiber atrophy, play in the manifestation of muscle weakness. This paper considers both the neural and mechanical components of spasticity and discusses, in terms of clinical intervention, the implications arising from recent research. Investigations suggest that the resistance to passive movement in individuals with spasticity is due not only to neural mechanisms but also to changes in mechanical properties of muscle. The emphasis is on training the individual to gain control over the muscles required for different tasks, and on preventing secondary and adaptive soft tissue changes and ineffective adaptive motor behaviours.

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An Improved Adaptive Scheduling Strategy Utilizing Simulated Annealing Genetic Algorithm for Data Center Networks

  • Wang, Wentao;Wang, Lingxia;Zheng, Fang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.11
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    • pp.5243-5263
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    • 2017
  • Data center networks provide critical bandwidth for the continuous growth of cloud computing, multimedia storage, data analysis and other businesses. The problem of low link bandwidth utilization in data center network is gradually addressed in more hot fields. However, the current scheduling strategies applied in data center network do not adapt to the real-time dynamic change of the traffic in the network. Thus, they fail to distribute resources due to the lack of intelligent management. In this paper, we present an improved adaptive traffic scheduling strategy utilizing the simulated annealing genetic algorithm (SAGA). Inspired by the idea of software defined network, when a flow arrives, our strategy changes the bandwidth demand dynamically to filter out the flow. Then, SAGA distributes the path for the flow by considering the scheduling of the different pods as well as the same pod. It is implemented through software defined network technology. Simulation results show that the bisection bandwidth of our strategy is higher than state-of-the-art mechanisms.

Dynamic Channel Allocation Control with thresholds in Wireless Cellular Networks using Simpy

  • Cao, Yang;Ro, Cheul-Woo
    • International Journal of Contents
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    • v.8 no.2
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    • pp.19-22
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    • 2012
  • New and handoff calls control mechanisms are the key point to wireless cellular networks. In this paper, we present an adaptive algorithm for dynamic channel allocation scheme with guard channels and also with handoff calls waiting queue ensuring that handoff calls take priority over new calls. Our goal is to find better tradeoff between handoffs and new calls blocking probabilities in order to achieve more efficient channel utilization. Simpy is a Python based discrete event simulation system. We use Simpy to build our simulation models to get analytical data.

An Adaptive Vehicle Platoon Formation Mechanism for Road Capacity Improvement (도로 용량 증대를 위한 적응적 차량 플라툰 형성 기법)

  • Su, Dongliang;Ahn, Sanghyun
    • KIPS Transactions on Computer and Communication Systems
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    • v.5 no.10
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    • pp.327-330
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    • 2016
  • In the road environment with lots of vehicles, we can increase the number of vehicles on the road (i.e., road capacity) and enhance the comfortability of drivers if vehicles are organized into platoons. In the traditional vehicle platooning mechanisms, a pre-determined set of vehicles are allowed to form a platoon and, among them, a specific vehicle is designated as the platoon leader. In this type of platoon mechanisms, platoon is limited in improving the road capacity because the vehicles allowed to involve into platooning are restricted. Therefore, in this paper, we propose an adaptive platoon formation mechanism that allows any vehicle to be a platoon leader from which a platoon is formed. In the proposed mechanism, a platoon leader is elected based on the relative velocity and location information of neighboring vehicles obtained through the periodic exchange of beacon messages among vehicles. Through the NS-3 based simulations, we show the performance of our proposed mechanism in terms of road capacity improvement.