• 디지털산업정보학회논문지
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• 제7권4호
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• pp.7-14
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• 2011

Infinite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rate per fault (hazard function). This infinite non-homogeneous Poisson process is model which reflects the possibility of introducing new faults when correcting or modifying the software. In this paper, polynomial hazard function have been proposed, which can efficiency application for software reliability. Algorithm for estimating the parameters used to maximum likelihood estimator and bisection method. Model selection based on mean square error and the coefficient of determination for the sake of efficient model were employed. In numerical example, log power time model of the existing model in this area and the polynomial hazard function model were compared using failure interval time. Because polynomial hazard function model is more efficient in terms of reliability, polynomial hazard function model as an alternative to the existing model also were able to confirm that can use in this area.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.60.3-60
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• 2001

Usually the static scheduling algorithms such as DMS(Deadline Monotonic Scheduling) or RMS(Rate Monotonic Scheduling) are used for CAN scheduling due to its ease with implementation. However, due to their inherently low utilization of network media, some dynamic scheduling approaches have been studied to enhance the utilization. In case of dynamic scheduling algorithms, two considerations are needed. The one is a priority inversion due to rough deadline encoding into stricted arbitration fields of CAN. The other is an arbitration delay due to the non-preemptive feature of CAN. In this paper, an extended algorithm is proposed from an existing EDS(Earliest Deadline Scheduling) approach of CAN scheduling algorithm having a solution to the priority inverstion ....

• 인터넷정보학회논문지
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• 제6권2호
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• pp.25-35
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• 2005

실시간 스케줄링 알고리즘에서는 비율단조(RM) 스케줄링 알고리즘과 마감시한(EDF) 스케줄링 알고리즘이 가장 일반적으로 사용되고 있다. 이러한 알고리즘에서는 태스크 집합의 전체 이용율 값을 가지고 수행 가능성을 판별하였다. 그러나 임의의 태스크에서 이용율 값이 초과되면 개별 태스크의 한계성을 전혀 예측할 수 없는 문제점이 있었다. 본 논문에서 제안한 알고리즘은 이용율 값이 초과한 태스크를 예측하고, 개별 태스크의 이용율 값을 기반으로 스케줄링 가능성 여부를 판단하는 방법을 제시하였다. 또한, 실시간 시스템에서 스케줄링 가능성 검사의 한계성을 시뮬레이션을 통해 예측하고 결과를 분석하였다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2013년도 춘계학술발표대회
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• pp.438-441
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• 2013

자동차 관련 기술은 점차 전기, 전자 장치로 빠르게 바뀌어 가고 있다. 차량 내 연결되어 있는 전자 제어 장치들도 그에 따라 증가하게 되었고 장치간의 통신 성능도 중요하게 되었다. 가장 널리 사용되고 있는 차량용 네트워크 프로토콜로는 CAN(Controller Area Network)을 들 수 있다. 그러나 최근 통신 복잡도가 증가함에 따라 주기적 메시지 통신의 메시지 전송 지연 및 중단이 발생되고 있다. 본 논문에서는 이러한 문제에 대한 해결 방안을 제시하기 위해 메시지들의 스케줄 가능성 및 응답시간에 따른 실 시간성 검증 모델을 제안한다. CAN 메시지 수신 시 RMA(Rate Monotonic Algorithm)기반으로 메시지 스케줄 가능성 평가 모델을 개발하였다. 또한, CAN 메시지를 송신할 경우 RTA(Response Time Analysis)를 고려한 실 시간성 평가 모델을 제시하였다. 실험 1 에서는 기존 RMA 기법으로 통신을 수행한 결과 통신 중 중단되는 현상을 확인하였고 이후 제안 모델에서는 23%정도의 추가 시간을 확보하여 통신을 완료하는 것을 증명하였다. 실험 2 에서는 메시지 통신의 응답시간이 모두 제안된 Worst-case 응답시간 이내로 측정되어 실 시간성을 만족함을 확인하였다.

• 한국표면공학회지
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• 제41권6호
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• pp.269-273
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• 2008

The etch of $(Na_{0.5}K_{0.5})NbO_3$ (NKN) thin film was performed in $BCl_3/Cl_2/Ar$ inductively coupled plasma. It was found that the 1sccm addition $BCl_3$ (5%) into $Cl_2/Ar$ plasma caused a non-monotonic behavior of the NKN etch rate. The maximum etch rate of NKN was 95.3 nm/min at $BCl_3$ (1 sccm)/$Cl_2$ (16 sccm)/Ar (4 sccm), 800 W ICP power, 1 Pa pressure and 400 W bias power. The NKN etch rate shows a monotonic behavior a s the bias power increases. The analysis of the narrow scan spectra of XPS for both a s-deposited and etched NKN films allowed one to assume ion assisted etch mechanism. The most probable reason for the maximum etch rate can be defined as a concurrence of chemical and physical etch pathways.

• Computers and Concrete
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• 제17권1호
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• pp.1-27
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• 2016

Final construction project cost is significantly determined by construction rate. The Industrialized Building System (IBS) was promoted to enhance the importance of prefabrication technology rather than conventional methods in construction. Ensuring the stability of a building constructed by using IBS is a challenging issue. Accordingly, the connections in a prefabricated building have a basic, natural, and essential role in providing the best continuity among the members of the building. Deficiencies of conventional precast connections were observed when precast buildings experience a large induced load, such as earthquakes and other disasters. Thus, researchers aim to determine the behavior of precast concrete structure with a specific type of connection. To clarify this problem, this study investigates the capacity behavior of precast concrete panel connections for industrial buildings with a new type of precast wall-to-wall connection (i.e., U-shaped steel channel connection). This capacity behavior is compared with the capacity behavior of precast concrete panel connections for industrial buildings that used a common approach (i.e., loop connection), which is subjected to monotonic loading as in-plane and out-of-plane loading by developing a finite element model. The principal stress distribution, deformation of concrete panels and welded wire mesh (BRC) reinforcements, plastic strain trend in the concrete panels and connections, and crack propagations are investigated for the aforementioned connection. Pushover analysis revealed that loop connections have significant defects in terms of strength for in-plane and out-of-plane loads at three translational degrees of freedom compared with the U-shaped steel channel connection.

• 융합보안논문지
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• 제6권3호
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• pp.145-153
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• 2006

본 논문에서는 기록값 통계량을 이용한 무한 고장 NHPP 모형들이 제안되었다. 이 모형들은 결함당 고장 발생률이 단조 증가하거나 단조 감소하는 패턴을 가진다. 그리고 수명 분포에서는 어랑 분포, 랄리 분포와 굼벨를 이용한 소프트웨어 신뢰성 모형을 적용하여 비교연구에 초점을 두었다. 고장 간격 시간 자료를 이용한 무한 고장 NHPP 모형들에 대한 모수 추정법은 최우 추정법을 사용하였고 적용 분포들의 적용을 용이하게 하기 위하여 특수한 형태를 제시하였다. 고장 자료의 분석을 위하여 산술 및 라플라스 추세 검정과 적합도 및 치우침 검정을 실시하여 그 결과를 나열하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2369-2373
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• 2001

Usually the static scheduling algorithms such as DMS (Deadline Monotonic Scheduling) or RMS(Rate Monotonic Scheduling) are used for CAN scheduling due to its ease with implementation. However, due to their inherently low utilization of network media, some dynamic scheduling approaches have been studied to enhance the utilization. In case of dynamic scheduling algorithms, two considerations are needed. The one is a priority inversion due to rough deadline encoding into stricted arbitration fields of CAN. The other is an arbitration delay due to the non-preemptive feature of CAN. In this paper, an extended algorithm is proposed from an existing EDS(Earliest Deadline Scheduling) approach of CAN scheduling algorithm haying a solution to the priority inversion. In the proposed algorithm, the available bandwidth of network media can be checked dynamically by all nodes. Through the algorithm, arbitration delay causing the miss of their deadline can be avoided in advance. Also non real-time messages can be processed with their bandwidth allocation. The proposed algorithm can achieve full network utilization and enhance aperiodic responsiveness, still guaranteeing the transmission of periodic messages.

• Geomechanics and Engineering
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• 제36권3호
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• pp.247-258
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• 2024

Tailings are waste materials of mining operations, consisting of a mixture of clay, silt, sand with a high content of unrecoverable metals, process water, and chemical reagents. They are usually discharged as slurry into the storage area retained by dams or earth embankments. Poor knowledge of the hydro-mechanical behaviour of tailings has often resulted in a high rate of failures in which static liquefaction has been widely recognized as one of the major causes of dam collapse. Many studies have dealt with the static liquefaction of coarse soils in saturated conditions. This research provides an extension to the case of silty tailings in unsaturated conditions. The static liquefaction resistance was evaluated in terms of stress-strain behavior by means of monotonic triaxial tests. Its dependency on the preparation method, the volumetric water content, the void ratio, and the degree of saturation was studied and compared with literature data. The static liquefaction response was proved to be dependent mainly on the preparation technique and degree of saturation that, in turn, controls the excess of pore pressure whose leading role is investigated by means of the relationship between the -B Skempton parameter and the degree of saturation. A preliminary interpretation of the static liquefaction response of Stava tailings is also provided within the Critical State framework.

• 한국국방경영분석학회지
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• 제25권1호
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• pp.199-214
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• 1999

The Constructive Battle Simulation Model is very important to the recent military training for the substitution of the field training. However, real battlefield systems operate under real-time conditions, they are inherently distributed, concurrent and dynamic. In order to reflect these properties by the computer-based simulation systems which represent real world processes, we have been developing constructive simulation model for several years. Conventionally, scheduling and resource allocation activities which have timing constraints, we elaborated on these issues and developed the simulation system on commercially available hardware and operating system with lock-free resource allocation scheme and rate monotonic scheduling.