• Defense and Technology
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• no.3 s.145
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• pp.26-33
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• 1991

NATO 프리깃함(NFR-90) 계획의 붕괴를 1990년대 프로그램의 손상이라고 언급하는 것은 과장된 말이 아니다. 많은 시간, 열정 및 예산이 사용되었으며, NFR-90이 개혁의 개념을 가지기 시작했다는 관점에서 참가국의 희망이 고조되어 왔다. 따라서 1989년 이 계획의 중단은 상당한 대이변이었다. NFR-90의 주된 실패 요인은 전함 설계의 실상을 무시한 것이었다. NFR-90 사업의 참가국은 미국, 캐나다, 영국, 프랑스, 이탈리아, 서독, 네덜란드 및 스페인 등 8개국이었다

• The Journal of the Korean dental association
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• v.51 no.5
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• pp.255-264
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• 2013

Many concept of occlusion have been introduced in the past, but there isn't any generally accepted unified theory since a single occlusion theory cannot represent the natural perfection, especially considering the difference in clinical experience, the dynamic occlusion, and individual diversity in mastication pattern. NAT(Naturgemasse Aufwachstechnik)/NFR((Natur Funktionsgerechte Rekonstruktion) occlusion is not just a theory on occlusion, but a clinical occlusion that can be practically applied to clinical practice by providing dynamic occlusion adjusted to the individual mastication pattern and biomechanics. This report aims to provide a guide to a clinically biomechanical occlusion through the teamwork of both the dentist and the lab technician by introducing the NAT occlusion through following: reviewing the concept of occlusion in terms of morphology, its correlation with NAT/NFR occlusion, reviewing the limitation of conventional occlusion theories, and introducing the clinical application of NAT/NFR.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.771-776
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• 2002

Optimal shape of the NFR suspension is studied and developed to improve the dynamic performance and reduce the vibration of the suspension system including a optical head slider. Since accurate position control and stability of the slider motion are highly required in NFR due to the narrower track width and the heavier slider than HDD slider with the low flying height, the dynamic characteristics of the suspension are very important to the mechanical performance of the system. The first natural frequencies in flexural and lateral motion of the suspension are critical factors affecting the dynamics and stability of the flying head, so that the dynamic parameters should be designed properly to avoid an excessive vibration or a crash of the slider on the disk. This paper optimizes the shape of the suspension based on homogenization method in NASTRAN and develops a new suspension shape for NFR system. The suspension is tested on experiment to verify the improvement of the dynamic characteristics.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.874-875
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• 2008

Gap servo NFR (Near Field Recording) system is one of technologies to reduce beam spot size by increasing NA (Numerical Aperture) of lens. To achieve high NA, SIL (Solid Immersion Lens) is used. In case of using a blue LD (405 nm) as the light source the gap distance should be controlled under 100 nm with much tighter margin. To develop NFR disc drive with very small gap distance between SIL bottom and the surface of media, we need to research for the vibration characteristics and design considerations. This paper deals with a study on vibration characteristic of NFR disc drive.

• KIPS Transactions on Software and Data Engineering
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• v.6 no.8
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• pp.391-400
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• 2017

Software architecture plays a key role in satisfying non-functional requirement (NFR), i.e. quality requirements and constraints. Architecture design methods and tactics for conventional NFR are largely available in literatures. However, the methods for the target system-specific non-conventional NFRs are not readily available; rather architects should invent the design methods from their experiences and intuitions. Hence, the hardship to design architectures for non-conventional NFRs is quite high. In this paper, we provide a systematic architecture design methodology for non-conventional NFRs. We provide a five-step process, and detailed instructions for the steps. In the process, we treat the traceability among artifacts and seamlessness as essential values for supporting effective architecture design. We apply the methodology on designing architectures for a platform software system. We believe that the proposed methodology can be effectively utilized in designing high quality architectures for non-conventional NFRs.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.4
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• pp.277-283
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• 2003

Recently, near-field recording (NFR) disk drive schemes have been proposed with a view to increasing recording densities of hard disk drives. Compared with hard disk drives. NFR disk drives have narrower track pitches and are exposed to more severe periodic disturbances resulting from eccentric rotation of the disk. It is difficult to meet servo system design specifications for NFR disk drives with conventional VCM actuators in that the servo system for an NFR disk drive generally requires a feater gain and higher bandwidth. To tackle the problem various dual-stage actuator systems composed of a microactuator mounted on top of a conventional VCM actuator have been proposed. This article deals with the problem of designing a tracking servo system far an NFR disk drive adopting a dual-stage actuator. We summarize design constraints pertaining to the dual-stage servo system and present a new servo scheme using iterative teaming control. We design feedback compensators and an iterative teaming controller for a target plant and verify the validity of the proposed control scheme through a computer simulation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.376.2-376
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• 2002

In this study, the shape of suspension load beam for NFR(Near Field Recording) was proposed, which was designed using Topology optimization based on Homogenization method. Lens and Micro-mirror are attached to the end of the suspension load beam for collection and control the light, which increasing the system mass. Increment of the system mass cause to decrease the tracking stiffness mode frequency. (omitted)

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2001.05a
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• pp.261-267
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• 2001

In this paper, we have illustrated implementations and there results of network attacks and detections. We consider two attacks, smurf attach and network mapping attack, which are one of the typical intrusions using the ICMP The NFR/sup TM/ is used to capture all of our interesting packets within the network traffic. We implement the smurf and network mapping attacks with the UNIX raw socket, and build the NFR's backend for it's detection. The N-Code programming is used to build the backend. The implementing results show the possibility of preventing illegal intruding to network systems.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.4
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• pp.295-302
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• 2004

In this study the optimization of a NFR suspension is performed using finite element method and experimental modal analysis. NFR suspensions are required to have low compliance modes to allow the slider to comply with the rotating disk, and high tracking stiffness modes to maximize the servo bandwidth of the tracking controller First of all, the dual suspension model is designed based on the characteristics of NFR drives. And the parametric study on the sensitivities of compliance modes and tracking stiffness modes is investigated. Finally, the model satisfying static characteristics is selected and shape optimization is performed to improve dynamic characteristics. A prototype of a NFR suspension is made by etching and modal ekperiment in free state is performed. The results of experiment almost agree with those of finite element method.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.688-693
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• 2002

Identification method is formulated to evaluate the dynamic characteristics of air bearings under NFR(Near Field Recording) sliders. Impulse responses and frequency response functions of NFR sliders are obtained on numerical non-linear models including rigid motion of slider and fluid motion of air bearing under the slider. Modal parameters and system parameters are identified by modal analysis method and instrumental variable method. The parameters of sliders are utilized to evaluate the dynamic characteristics of air bearings. Also, this study shows the difference between the dynamic characteristics of NFR and HDD slides, and squeeze effect of air bearings.