• 대한수학회보
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• 제54권5호
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• pp.1627-1654
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• 2017

We prove that in the parameter space of M-dimensional Fano complete intersections of index one and codimension two the locus of varieties that are not birationally superrigid has codimension at least ${\frac{1}{2}}(M-9)(M-10)-1$.

• Ocean Systems Engineering
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• 제4권2호
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• pp.137-150
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• 2014

In the marine industry although there has been significant growth towards safety, security and risk assessments or risk-based strategies such as marine insurance and regulations to avoid the risks of damage to properties and the environment or the prospect of premature death caused by accidents etc, the moves toward managing the risks which are linked directly to the business functions and decision making processes have been very slow. Furthermore in the marine industry most perceptions, methodologies and frameworks of dealing with hazards, risks, safety and security issues are for their assessment rather than their management. This trend reveals the fact that in different marine industry sectors such as logistics and shipping there is a lack of coherent risk management framework or methodology from which to understand the risk-based decisions especially for the purpose of design, construction, operation, management and even decommissioning of the marine related applications. On the other hand risk management is not yet viewed holistically in the marine industry in order to, for example, assign a right person, i.e. risk manager, who can act as a coordinator and advisor with responsibilities that are only specific to risk management. As a result this paper, by examining the present physical borders and risk-based activities in the marine industry, aims to propose an appropriate risk management methodology in addition to the emergent role of risk managers which will enable the industry users initially to become familiar with the concept of risk management at its holistic level. In the later stages this eventually can lead to development of risk management capabilities at an exclusive level and its integration into the marine industry functions in future.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제1권1호
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• pp.22-30
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• 2020

Many areas of vegetation in the British uplands have reduced species diversity as a result of sheep overgrazing. It has been suggested that abandonment or re-wilding strategies might be used to reverse this. A likely first step would be the removal or reduction of grazing livestock from upland areas, with a presumption that this would lead to a recovery in species richness. However, we do not know if this would work, or the timescales involved. One of the important areas where more knowledge is needed is information on the size and composition of soil seedbanks as regeneration from zseed is a likely pathway of recovery. Here, we compared seedbanks in both grazed and ungrazed plots in five experiments at Moor House NNR in the northern Pennines; these sheep grazing exclusion experiments were started 52 and 63/64 years ago. Soil samples (n=10) were collected from both grazed and ungrazed plots in each experiment, and seed emergence counted in glasshouse trials. We detected only seeds of common species and very few dicotyledonous species. This suggests that the soil seedbank is unlikely to be a reliable source of the less common species for ecological restoration in these upland communities, suggesting an extinction debt. Therefore, seed addition and the creation of suitable safe-sites for germination may be needed in conjunction with grazing controls to allow the establishment of plants that will increase the species richness of the vegetation. However, this interventionist restoration approach remains to be tested.

• 천문학논총
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• 제30권2호
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• pp.237-240
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• 2015

Classical novae (CNe) are interacting binary systems whose outbursts are powered by a thermonuclear runaway in accreted material onto the surface of a white dwarf (WD). The secondary star in such systems fills its Roche lobe and material is transferred onto the WD primary star via an accretion disk. Recurrent novae (RNe) show many similarities to CNe, but have had more than one recorded outburst. RNe play an important role as one of the suspected progenitor systems of Type Ia supernovae, which are used as primary distance indicators in cosmology. Thus, it is important to investigate the nature of their central binary systems to determine the relation between the parameters of the central system and the outburst type, and finally ascertain the population of novae that might be available to give rise to the progenitors of Type Ia SNe. A low outburst amplitude is adopted as a criterion that may help distinguish RNe from CNe and was therefore used to select targets for observations from ground-based observatories including the Liverpool Telescope and the Southern African Large Telescope as well as the full-sky space-based archive of the Solar Mass Ejection Imager (SMEI). We found that at least four objects currently classified as CNe are possibly RNe candidates based on their quiescent spectra. We also searched the SMEI archive for additional outbursts of bright CNe that might otherwise have been missed but did not find a conclusive example.

• International Journal of Automotive Technology
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• 제8권5호
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• pp.637-650
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• 2007

A new on-line fault detection and isolation(FDI) scheme has been proposed for engines using an adaptive neural network classifier; this paper investigates the robustness of this scheme by evaluating in a wide range of operational modes. The neural classifier is made adaptive to cope with the significant parameter uncertainty, disturbances, and environmental changes. The developed scheme is capable of diagnosing faults in the on-line mode and can be directly implemented in an on-board diagnosis system(hardware). The robustness of the FDI for the closed-loop system with crankshaft speed feedback is investigated by testing it for a wide range of operational modes, including robustness against fixed and sinusoidal throttle angle inputs, change in load, change in an engine parameter, and all changes occurring simultaneously. The evaluations are performed using a mean value engine model(MVEM), which is a widely used benchmark model for engine control system and FDI system design. The simulation results confirm the robustness of the proposed method for various uncertainties and disturbances.

• Advances in concrete construction
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• 제3권1호
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• pp.1-14
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• 2015

China accounts for nearly half of the global steel production. As a waste material or a by-product in the manufacture process, a large amount of blast furnace slag is generated every year. The majority of recycled blast furnace slag is used as an additive in low-grade blended cement in China (equivalent to the UK CEM II or CEM III depending on the slag content). The cost of using ground granulated blast furnace slag (GGBS) in such low-grade applications may not be entirely reimbursed based on market research. This paper reports an on-going project at Xi'an Jiaotong-Liverpool University (XJTLU) which investigates the feasibility of using GGBS in long-span concrete structures by avoiding/reducing the use of crack control reinforcement. Based on a case study investigation, with up to 50% of CEM I cement replaced with GGBS, a beneficiary effect of reduced thermal contraction is achieved in long-span concrete slabs with no significant detrimental effect on early-age strengths. It is believed that this finding may be transferable from China to other Asian countries with similar climates and economic/environmental concerns.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2003년도 학술발표회논문집(1)
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• pp.489-492
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• 2003

• 대한근관절건강학회:학술대회논문집
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• 대한근관절건강학회 2003년도 제19회 추계 학술대회
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• pp.218-219
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• 2003

• Endocrinology and Metabolism
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• 제33권4호
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• pp.493-494
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• 2018

• 중소기업융합학회논문지
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• 제4권1호
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• pp.31-39
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• 2014

PID 오토 튜닝 컨트롤러는 퍼지 논리를 통해 설계되었다. 이러한 오류 및 오류 파생 의견으로 일반적인 값은 발견적 표현으로 변경, 그들은 퍼지 및 defuzzification 과정을 통해 PID 이득을 결정했다. 퍼지 절차 및 PID 제어기 설계는 개별적으로 간주하고, 그것들을 혼합하고, 분석 하였다. 퍼지 논리에 의해 획득 자동 조정 PID 컨트롤러는 3 차 플랜트 제어 이하의 능력을 보여 주었다. 또한 설계된 자동 동조 방식으로 추적 문제를 참조하는 데 적용한다.