• Smart Structures and Systems
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• v.13 no.2
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• pp.219-233
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• 2014

In a companion paper, Pasala and Nagarajaiah analytically and experimentally validate the Adaptive Length Pendulum Smart Tuned Mass Damper (ALP-STMD) on a primary structure (2 story steel structure) whose frequencies are time invariant (Pasala and Nagarajaiah 2012). In this paper, the ALP-STMD effectiveness on a primary structure whose frequencies are time varying is studied experimentally. This study experimentally validates the ability of an ALP-STMD to adequately control a structural system in the presence of real time changes in primary stiffness that are detected by a real time observer based system identification. The experiments implement the newly developed Adaptive Length Pendulum Smart Tuned Mass Damper (ALP-STMD) which was first introduced and developed by Nagarajaiah (2009), Nagarajaiah and Pasala (2010) and Nagarajaiah et al. (2010). The ALP-STMD employs a mass pendulum of variable length which can be tuned in real time to the parameters of the system using sensor feedback. The tuning action is made possible by applying a current to a shape memory alloy wire changing the effective length that supports the damper mass assembly in real time. Once a stiffness change in the structural system is detected by an open loop observer, the ALP-STMD is re-tuned to the modified system parameters which successfully reduce the response of the primary system. Significant performance improvement is illustrated for the stiffness modified system, which undergoes the re-tuning adaptation, when compared to the stiffness modified system without adaptive re-tuning.

• Journal of the Korea Society of Computer and Information
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• v.13 no.6
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• pp.117-125
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• 2008

The Object tracking by real-time image analysis is one of the major concerns in computer vision and its application fields. The Object detection process of real-time images must be preceded before the object tracking process. To achieve the stable object detection performance in the exterior environment, adaptive background model generation methods are needed. The adaptive background model can accept the nature's phenomena changes and adapt the system to the changes such as light or shadow movements that are caused by changes of meridian altitudes of the sun. In this paper, we propose a robust background model generation method effective in an illegal parking auto-detection application area. We also provide a evaluation method that judges whether a moving vehicle stops or not. As the first step, an initial background model is generated. Then the differences between the initial model and the input image frame is used to trace the movement of object. The moving vehicle can be easily recognized from the object tracking process. After that, the model is updated by the background information except the moving object. These steps are repeated. The experiment results show that our background model is effective and adaptable in the variable exterior environment. The results also show our model can detect objects moving slowly. This paper includes the performance evaluation results of the proposed method on the real roads.

• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.2
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• pp.75-80
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• 2006

Changes in the levels of protein and free amino acids in the haemolymph of three selected races of the silkworm, Bombyx mori viz., PM, $NB_4D_2$ and $CSR_2$, were investigated during 4th moult, 5th instar and pupal period. The levels of total protein in the haemolymph, increased from first day of 5th instar till sixth day. From seventh day till spinning, the protein levels decreased in all the three races. A sustained decrease in the haemolymph proteins was observed during the pupal development in all the three races. The levels of free amino acids, which were high during 4th moult, declined through the 5th age of larval development till spinning. PM showed a relatively higher free amino acid level (3.192 mg/ml) in haemolymph followed by $NB_4D_2$ (2.601 mg/ml) and $CSR_2$ (2.35 mg/ml). The free amino acid levels decreased gradually from prepupal stage but increased again at the end of pupal period. Racial differences in the changes in the levels of protein and free amino acids in the haemolymph were observed in the larvae and pupae when subjected to two high temperature regimes of $30^{\circ}C$ and $35^{\circ}C$. The results showed that high temperature induces specific changes in the metabolism (reversible thermal stress) that have different adaptive value in different races of the silkworm. Relatively higher increase in the free amino acid levels in the haemolymph of Pure Mysore presumably provides protective cover to tissues against high temperature by an increase in osmolarity and reduction in evaporative water loss. The absence of such a mechanism may be responsible for temperature susceptibility of the bivoltine races like $NB_4D_2$ and $CSR_2$.

• Journal of KIISE:Software and Applications
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• v.37 no.7
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• pp.568-572
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• 2010

Self-healing is one of the techniques that assure dependability of mission-critical system. Self-healing consists of fault detection and fault recovery and fault detection is important first step that enables fault recovery but it causes overhead. We can detect fault based on model, the detection tasks that notify system's behavior and compare normal behavior model and system's behavior are heavy jobs. In this paper, we propose architecture-based multi-level self-adaptive monitoring method that complements model-based fault detection. The priority of fault detection per component is different in the software architecture. Because the seriousness and the frequency of fault per component are different. If the monitor is adapted to intensive to the component that has high priority of monitoring and loose to the component that has low priority of monitoring, the overhead can be decreased and the efficiency can be maintained. Because the environmental changes of software and the architectural changes bring the changes at the priority of fault detection, the monitor learns the changes of fault frequency and that is adapted to intensive to the component that has high priority of fault detection.

• Journal of Life Science
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• v.29 no.7
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• pp.817-823
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• 2019

Immune system provides defense integrity of body against external invaders. In order to accomplish the important defending role immune system is composed of many different components which are regenerated continuously during lifespan. The key components are professional killing cells such as macrophage, neutrophil, natural killer cell, and cytotoxic T cell and professional blocking molecule, antibody, which is produced by plasma cell, the terminal differentiated B cell. Immune response is orchestrated harmoniously by all these components mediated through antigen presenting cells such as dendritic cells. Immune responses can be divided into two ways: innate immune response and adaptive immune response depending on induction mechanism. Aging is a broad spectrum of physiological changes. Likewise other physiological changes, the immune components and responses are wane as aging is progressing. Immune responses become decline and dysregulating, which is called immunosenescense. Immune components of both innate and adaptive immune response are affected as aging progresses leading to increased vulnerability to infectious diseases. Numbers of immune cells and amounts of soluble immune factors were decreased in aged animal models and human and also functional and structural alterations in immune system were reduced and declined. Cellular intrinsic changes were discovered as well. Recent researches focusing on aging have been enormously growing. Many advanced tools were developed to bisect aging process in multi-directions including immune system area. This review will provide a broad overview of aging-associated changes of key components of immunity.

• Journal of Soil and Groundwater Environment
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• v.28 no.3
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• pp.12-28
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• 2023

Each national groundwater monitoring well showed distinct change patterns in groundwater levels and electrical conductivity (EC) in the Nakdong River Estuary, implying different external forces (EFs) on each well. According to the annual average data in 1997-2020, seawater was invaded into Well C. The desalination rate of -1,062 µS/cm/year represents the adaptive capacity of the well to seawater intrusion. The water levels and EC in Well E responded to precipitation, indicating the low absorptive capacity to climate changes. Meanwhile, Well B showed constant increases in water levels, suggesting that problems by rising groundwater should be considered in the study area where confined aquifers are overlaid by clay aquitards. The other wells showed consistent water levels and EC, indicating resilience to EFs. Here, resilience is the capacity of a well to resist changes by EFs, including the absorptive and adaptive capacity. The resilience of Wells E and F to climate changes was quantitatively compared using a resilience cost (RC). The RC showed Well F was more resilient than Well E, and the bedrock aquifer was more resilient than the alluvium aquifer, supporting the usefulness of RC. The resilience assessment against EFs (e.g., changes in land use and climate) helps sustainable groundwater management.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.3
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• pp.39-48
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• 2013

Ontology has an important role in semantic web to construct and query semantic data. When system make changes to ontologies, questions arise about versioning of these changes. Applying this changes on a dynamic environment is even more important. To apply these changes, change specification method is needed. Early studies show RDF-based syntax for the operations between old and new ontologies. When several ontology versions can be used for some query, if possible, using possible newest version ontology with prospective use is best way to process the query. Prospective use of ontology means using a newer version of an ontology with a data source that conforms to a more recent ontology. In this paper, for prospective use of ontology version, structure of change specification of class and property through several ontology versions is proposed. From this, efficient adaptive ontology version selection for a query can be possible. Algorithm for structure of version transition representation is proposed and simulation results show possible newest version number for queries.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1092-1098
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• 2002

This paper discusses the composition of the theory of reinforcement teaming, which is applied in real-time teaming, and evolutionary strategy, which proves its the superiority in the finding of the optimal solution at the off-line teaming method. The individuals are reduced in order to team the evolutionary strategy in real-time, and new method that guarantee the convergence of evolutionary mutations are proposed. It is possible to control the control object varied as time changes. As the state value of the control object is generated, applied evolutionary strategy each sampling time because of the teaming process of an estimation, selection, mutation in real-time. These algorithms can be applied, the people who do not have knowledge about the technical tuning of dynamic systems could design the controller or problems in which the characteristics of the system dynamics are slightly varied as time changes. In the future, studies are needed on the proof of the theory through experiments and the characteristic considerations of the robustness against the outside disturbances.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.3
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• pp.293-305
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• 2011

A special concern is paid to the risks with which small-sized water resources systems are confronted in supplying water in the far future. Taking the Gwangdong dam reservoir as a case study, the authors seek to understand demand-side and supply-side disturbances of a reservoir, which, respectively, corresponds to effects of water demand changes on the intake amount and those of climate changes on the inflow amount. In result, it is demonstrated that both disturbances in the next 50 years are almost unpredictable. Yet the projection ranges, thought of as relatively reliable information that models offer, reveal that severity and period of water shortage is very likely to change. It is therefore concluded that water resources management requires more rigorous approaches to overcoming high uncertainties. The methods and models for projecting those disturbances are selected, based on practicality and applicability. Nevertheless, they show a large usefulness, especially in dealing with data shortage and reducing the needs for expensive modeling resources.

• Journal of Electrical Engineering and Technology
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• v.8 no.3
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• pp.530-543
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• 2013

This paper describes a control scheme of speed sensorless fuzzy direct torque control (FDTC) of permanent magnet synchronous motor for electric vehicle (EV). Electric vehicle requires fast torque response and high efficiency of the drive. Speed sensorless FDTC In-wheel PMSM drives without mechanical speed sensors at the motor shaft have the attractions of low cost, quick response and high reliability in electric vehicle application. This paper presents a new approach to estimate the speed of in-wheel electrical vehicles based on Model Reference Adaptive System (MRAS). The direct torque control suffers in low speeds due to the effect of changes in stator resistance on the flux measurements. To improve the system performance at low speeds, a PI-fuzzy resistance estimator is proposed to eliminate the error due to changes in stator resistance. High performance sensorless drive of the in-wheel motor based on MRAS with on line stator resistance tuning is established for four motorized wheels electric vehicle and the whole system is simulated by matalb/simulink. The simulation results show the effectiveness of the new control strategy. This proposed control strategy is extensively used in electric vehicle application.