• Title/Summary/Keyword: High availability

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Competition for Water in Two Populations of Impatiens pallida (Balsaminaceae) from Contrasting Water Environments (수분환경이 다른 서식지에서 자란 Impatiens pallida 의 두 개체군간 수분에 대한 경쟁)

  • Yang, Hyo-Sik;James B. McGraw
    • The Korean Journal of Ecology
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    • v.19 no.2
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    • pp.165-178
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    • 1996
  • We investigated the role of competition in adaptation to varying water availability levels for two ecotypically-differentiated populations of Impatiens pallida found naturally in low- vs. high-water environments. In a greenhouse experiment, seedlings were grown in pure cultures at two densities (n=1 and 2 plants per pot) and in mixed cultures (n=2) under low-, medium- and high-water treatments. The two populations were shown to be genetically distinct across the range of environmental conditions in the greenhouse experiment, confirming previous findings. The two populations had similar morphological responses to density and water availability in pure cultures and mixtures, but the population from the high-water environment showed a greater growth response to high water availability than did the population from the low-water environment and the difference in growth between the two populations decreased from the high-water to low-water treatment. Relative competitive ability of two populations were compared under three different water treatments and two densities. Differential response to watering treatment and density were not reflected in a difference in relative competitive ability. Relative yield totals were significantly greater than 1 overall. The niche differentiation suggested by RYTs>1 may be responsible for the lack of differential competitive effects observed for populations in the three vatering treatments.

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A Study on the Application Model of High Availability of shipboard Combat Systems (함정 전투체계 고가용도 모델 적용에 관한 연구)

  • Lee, Kyoung-Haing;Han, Dong-Soo
    • Journal of the Korea Society for Simulation
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    • v.24 no.4
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    • pp.119-125
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    • 2015
  • This research has conducted high availability system modeling to assure the reliability of shipboard combat systems. Shipboard combat system is a way for efficient execution of duty and a crucial battlefield management system that determines the outcome of battle in the modern war. Especially in regard to a network-centric operational environment in the future, even 1% of malfunction can lead to fatal consequences for the outcome of war. So combat system should be designed by high availability system which is a "always-on" service. In this point of view, This work describes an architecture-based various high availability model and proposed alternative high available systems that can achieve more than 99.9999% accuracy at a minimum. This paper also provides an applicable model with which system engineers analyze out system failure and recovery process by employing computerized tools.

An Autonomic Self-management Mechanism for High-available Home Service Networked System (고가용성 홈 서비스 네트워크 시스템을 위한 오토노믹 자가 관리 메커니즘)

  • Choi, Chang-Yeol;Kim, Sung-Soo
    • Journal of KIISE:Computing Practices and Letters
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    • v.13 no.2
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    • pp.119-130
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    • 2007
  • Home service networked systems require a high-availability service with a proactive and practical fault management. However, as the system complexity grows, it is not easy to meet the requirement. Moreover, user may want to pay no attention to a sequence of complex or nervous maintenance jobs for system fault managements. Therefore, the home service networked systems must have self & remote fault management capability with a minimal human intervention for meeting high-availability requirement of the integrated systems that consist of the networked appliances or devices. In this paper, we present an autonomic healing utility equipped with a remote self-managing mechanism in order to both increase the availability of home service networked systems and decrease the maintenance cost.

AMPK activation and adenine nucleotide content in skeletal muscle following different types of high fat feeding

  • Kim, Hyun-Kook;Lee, Songsam
    • Korean Journal of Exercise Nutrition
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    • v.16 no.1
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    • pp.35-41
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    • 2012
  • We investigated the role of fatty acid availability on skeletal muscle AMPK activity and adenine nucleotide content. To investigate the chronic effects of elevated fatty acid in vivo Sprague-Dawley rats were fed a chow diet (15% fat) or a diet high in saturated (SAFA, 52% fat) or polyunsaturated (PUFA, 52% fat) fat for eight weeks. High fat diets increased (P < 0.05) plasma FFA levels by 25%. AMPK activity was increased in SAFA and PUFA rats and occurred in the absence of changes in ATP, AMP, phosphocreatine and glycogen content. These results suggest that increasing fatty acid availability increases AMPK activity independent of changes in the cellular energy charge, and implicate the regulation of AMPK by a covalent mechanism. These data also support the contention that increasing fatty acid availability can increase subsequent fatty acid oxidation by an AMPK-mediated process.

Changes in Availability of Toxic Trace Elements (TTEs) and Its Effects on Soil Enzyme Activities with Amendment Addition

  • Lee, Sang-Hwan;Park, Misun;Kim, Min-Suk
    • Ecology and Resilient Infrastructure
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    • v.7 no.2
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    • pp.134-144
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    • 2020
  • In-situ stabilization is a remediation method using amendments to reduce contaminant availability in contaminated soil. We tested the effects of two amendments (furnace slag and red mud) on the availability of toxic trace elements (TTEs) and soil enzyme activities (dehydrogenase, phosphatase, and urease). The application of amendments significantly decreased the availability of TTEs in soil (p < 0.05). The decreased availability of TTE content in soils was accompanied by increased soil enzyme activities. We found significant negative relationships between the TTE content assessed using Ca(NO3)2-, TCLP, and PBET extraction methods and soil enzyme activities (p < 0.01). Soil enzyme activities responded sensitively to changes in the soil environment (pH, EC, and availability of TTEs). It could be concluded that soil enzyme activities could be used as bioindicators or ecological indicators for soil quality and health in environmental soil monitoring owing to their high sensitivity to changes in soil.

A Study of Basic Design Method for High Availability Clustering Framework under Distributed Computing Environment (분산컴퓨팅 환경에서의 고가용성 클러스터링 프레임워크 기본설계 연구)

  • Kim, Jeom Goo;Noh, SiChoon
    • Convergence Security Journal
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    • v.13 no.3
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    • pp.17-23
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    • 2013
  • Clustering is required to configure clustering interdependent structural technology. Clustering handles variable workloads or impede continuity of service to continue operating in the event of a failure. Long as high-availability clustering feature focuses on server operating systems. Active-standby state of two systems when the active server fails, all services are running on the standby server, it takes the service. This function switching or switchover is called failover. Long as high-availability clustering feature focuses on server operating systems. The cluster node that is running on multiple systems and services have to duplicate each other so you can keep track of. In the event of a node failure within a few seconds the second node, the node shall perform the duties broken. Structure for high-availability clustering efficiency should be measured. System performance of infrastructure systems performance, latency, response time, CPU load factor(CPU utilization), CPU processes on the system (system process) channels are represented.

RPS Periodic Testing Method for Reliability and Availability (신뢰성과 유지보수를 위한 원자로보호계통 주기시험 방법 개발)

  • Park, Joo-Hyun;Lee, Dong-Young;Lee, Seong-Jin;Song, Deok-Yong
    • Proceedings of the KIEE Conference
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    • 2005.05a
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    • pp.84-86
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    • 2005
  • The digital systems such as PLC or DCS have been applied to non-safety systems of nuclear power plants because of many difficulties in using analog systems. Nowadays, digital systems have been applied to safety systems of the plants such as reactor protection system. One of the main advantages of digital systems is applicability of automatic testing methods to the systems. The protection system requires high-reliability and high-availability because it shall minimize the propagation of abnormal or accident conditions of nuclear power plants. The calculation of reliability and availability of systems depends on the maintenance period of the system. In general, the maintenance period of the protection system is one-month in case of the manual test. However, the cycle of test can be shortened in several hours by using automatic periodic testing. The reliability and availability of the system is better when test period is shortened because the reliability and availability is inverse proportion to the test period. In this research, we developed the automatic periodic testing method for KNICS Reactor Protection System, which can test the system automatically without an operator or a tester. The automatic testing contained all functions of reaction protection systems from analog-to-digital conversion function of the bistable Processor to the coincident trip function of the coincident processor. By applying the automatic periodic testing to reaction system, the maintenance cost can be cut down and the reliability can be increased.

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Towards Instant Availability and Full Life Cycle Resilience in Vertical Cities: Automated Deployment and Transformation of High-Rise Buildings to Mitigate Social Challenges

  • Thomas Bock;Rongbo Hu
    • International Journal of High-Rise Buildings
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    • v.11 no.2
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    • pp.75-86
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    • 2022
  • High-rise buildings often can accommodate the population of small horizontal cities. The investment in high-rise buildings is considerable and therefore a rapid return on investment is necessary. The immediate availability of high-rise buildings can be achieved by automated prefabrication of highly finished modules and their instant on-site assembly by robotic and automated construction sites. A high-rise building as a vertical city can be considered as a sophisticated organism that can constantly change throughout its lifecycle in response to economic growth, demographic change, and environmental pressures. To date, many new urban high-rise developments claim to be "vertical cities", yet few represent this important characteristic. This article analyzed the technological readiness and innovations in the field of construction automation and robotics including single-task construction robots, automated on-site construction factories, and ambient assisted living. These technological advances enable the realization of future vertical cities that are able to continuously grow and transform in terms of form and function. Finally, the article proposes a visionary archetype of vertical city in the name of "dynamic vertical urbanism" that is easy to expand vertically and horizontally in order to achieve instant availability and full life cycle resilience thanks to advanced building technologies.

HA-PVFS : A PVFS File System supporting High Data Availability Adaptive to Temporal Locality (HA-PVFS : 시간적 지역성에 적응적인 데이터 고가용성을 지원하는 PVFS 파일 시스템)

  • Sim Sang-Man;Han Sae-Young;Park Sung-Yong
    • The KIPS Transactions:PartA
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    • v.13A no.3 s.100
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    • pp.241-252
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    • 2006
  • In cluster file systems, the availability of files has been supported by replicating entire files or generating parities on parity servers. However, those methods require very large temporal and spatial cost, and cannot handle massive failures situation on the file system. So we propose HA-PVFS, a cluster file system supporting high data availability adaptive to temporal locality. HA-PVFS restricts replication or parity generation to some important files, for that it employs an efficient algorithm to estimate file access patterns from limited information. Moreover, in order to minimize the performance degradation of the file system, it uses delayed update method and relay replication.

FDVRRP: Router implementation for fast detection and high availability in network failure cases

  • Lee, Changsik;Kim, Suncheul;Ryu, Hoyong
    • ETRI Journal
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    • v.41 no.4
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    • pp.473-482
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    • 2019
  • High availability and reliability have been considered promising requirements for the support of seamless network services such as real-time video streaming, gaming, and virtual and augmented reality. Increased availability can be achieved within a local area network with the use of the virtual router redundancy protocol that utilizes backup routers to provide a backup path in the case of a master router failure. However, the network may still lose a large number of packets during a failover owing to a late failure detections and lazy responses. To achieve an efficient failover, we propose the implementation of fast detection with virtual router redundancy protocol (FDVRRP) in which the backup router quickly detects a link failure and immediately serves as the master router. We implemented the FDVRRP using open neutralized network operating system (OpenN2OS), which is an open-source-based network operating system. Based on the failover performance test of OpenN2OS, we verified that the FDVRRP exhibits a very fast failure detection and a failover with low-overhead packets.