• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.8 s.111
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• pp.773-787
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• 2006

An airborne radar is an essential aviation electronic system for the aircraft to perform various civil and/or military missions in all weather environments. This paper presents the design, development, and test results of the multi-mode X-band pulsed Doppler radar system test model for helicopter-borne flight test. This radar system consists of 4 LRUs(Line-Replacement Unit), which include antenna unit, transmitter and receiver unit, radar signal & data processing unit and display Unit. The developed core technologies include the planar array antenna, TWTA transmitter, coherent I/Q detector, digital pulse compression, MTI, DSP based Doppler FFT filter, adaptive CFAR, moving clutter compensation, platform motion stabilizer, and tracking capability. The design performance of the developed radar system is verified through various ground fixed and moving vehicle test as well as helicopter-borne field tests including MTD(Moving Target Detector) capability for the Doppler compensation due to the moving platform motion.

• Journal of the Institute of Convergence Signal Processing
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• v.19 no.1
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• pp.20-27
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• 2018

In this paper, the problem of a double-parked car has been investigated and a method to solve it is studied. Double parking is very common in a public parking lot with insufficient parking space. If a double-parked car blocked the way, a person needs to push the double-parked car to move it. The problem is that moving a double-parked car with hands is very hard and dangerous, especially for the old and the weak. To solve the above mentioned problem, an automatic mover for a double-parked car is proposed and developed. The basic idea is that a double-parked car can be moved by rolling its one wheel. Two rollers are designed and manufactured, which are used to roll a wheel of a double-parked car. The developed automatic mover has two rollers, two driving wheels, and four castors. It also has several ultrasonic sensors so that it can detect obstacles in the way and prevent possible collision. It is verified through several experiments that the developed automatic mover can move a double-parked car safely and easily.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.11a
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• pp.502-511
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• 2002

컴퓨터의 기술적 발전은 사회 여러 분야에 막대한 영향을 끼쳤다. 그중 악보인식분야에도 커다란 영향을 주었다. 그러나, On-line 상에서 그린 악보를 실시간으로 정형화된 악보형태로 변환하는 처리에 대한 연구가 미흡하여 이에 대한 연구가 필요하다. 본 논문에서는 실시간으로 악보를 인식하고, 사용자의 편의를 도모하기 위해 DP(Dynamic Programming) 매칭 법을 이용한 On-Line 악보인식에 관한 방법을 제안하였다. 본 연구에서는 실시간으로 입력되는 악상기호를 인식하기 위해, 가장 유효한 정보인 악상 기호내의 방향, x, y 좌표를 이용하여 벡터형태로 추출한 후 음표와 비음 표(쉼표, 기타기호)의 두개의 그룹으로 나누어진 표준패턴과의 DP매칭을 통해 인식한다. 먼저 tablet을 통해 실시간으로 악상 기호를 입력할 때 생기는 x, y좌표를 이용하여, 펜의 움직임에 대한 16방향 부호화를 수행한다. 음표와 비 음표를 구분하기 위한 시간을 줄이고자 16방향 부호화를 적용하지 않고 사사분면부호화를 적용한다. 음표를 약식으로 그릴 경우 음표 머리에 해당하는 부분의 좌표는 삼사분면에 분포하고, 폐곡선의 음표일 경우에는 좌표가 사사분면에 고르게 나타난다. 폐곡선을 제외한 음표의 머리는 폐곡선과 같은 조건이면서 입력받은 y좌표 값들 중에서 최소 값과 최대 값을 구한 다음 2로 나눈 값을 지나는 y좌표의 개수가 임의의 임계값 이상이면 음표로 판단한다. 위 조건을 만족하지 않을 경우 비 음표로 취급한다. 음표와 비 음표를 결정한 다음, 입력패턴과 표준패턴과의 DP매칭을 통하여 벌점을 구한다. 그리고 경로탐색을 통해 벌점에 대한 각각의 합계를 구해 최소 값을 악상기호로 인식하였다. 실험결과, 표준패턴을 음표와 비음표의 두개의 그룹으로 나누어 인식함으로써 DP 매칭의 처리 속도를 개선시켰고, 국소적인 변형이 있는 패턴과 특징의 수가 다른 패턴의 경우에도 좋은 인식률을 얻었다.리되고 이원화된 코드체계와 데이터 형태의 이질화를 통일하는 방법으로 데이터웨어하우스 시스템을 제시하였다. 결국 병원에서 데이터웨어하우스 시스템의 구축은 임상, 연구, 교육의 유기적 순환관계를 정립하여 지식의 순환적 고리인 수집, 공유, 확산, 재창출을 지속적 유지할 수 있는 인프라를 구축해 준다. 반면 상이한 정보들간의 충돌과 이에 따른 해석의 오류로 잘못된 의사결정을 위한 정보를 제공할 수 있고 기초정보의 접근 및 추출의 유용성에 의해서 정보유출에 대한 문제가 한계점으로 나타났다.로세스 개선을 위해서 무엇을 정말로 필요로 하는지를 밝힘으로써, 한국 소프트웨어 산업의 현실적인 특수성을 고려한 소프트웨어 프로세스 평가와 개선 모델의 개발을 위한 기초적인 자료를 제공할 것으로 예상된다. 또한, 본 연구 결과는, 우리나라 소프트웨어 조직들이 실제로 무엇을 필요로 하는지를 밝힘으로써, 우리나라의 소프트웨어 산업을 육성하기 위한 실효성 있는 정책 입안을 위한 기초 자료를 제공할 것으로 예상된다.를 검증하려고 한다. 협력체계 확립, ${\circled}3$ 전문인력 확보 및 인력구성 조정, 그리고 ${\circled}4$ 방문보건사업의 강화 등이다., 대사(代謝)와 관계(關係)있음을 시사(示唆)해 주고 있다.ble nutrient (TDN) was highest in booting stage (59.7%); however no significant difference was found among other stages. The concentrations of Ca and P were not different among mature stages. According to these results, the yellow ripe period is appropriate to harvest the whole crop rice for forage considering

• Sijohaknonchong
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• v.30
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• pp.91-107
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• 2009

This study is to examine how Sijo is being accommodated to modern Gagok by comparing them. In details, the work is about comparison between three verses in Sijo and twofold grouping in modern Gogok, JoongYuUm in traditional Gagok, YuBak in Sijo, the interlude, ADanSungJang, and changing verses in modern Gagok. First point is about three verses in Sijo and a rhythm of twofold grouping in modern Gagok. In particular, modern Gagok is treated as a group of twofold leaving three verses of Sijo. The way is chosen that whether it sets on an interlude into a song or the third part of three verses in Sijo is extended to avoid its logic of music and poem. Second, the discussion moves points on between an interlude in traditional Gagok and in Sijo. In the process of grouping twofold in modern Gagok, the parts which are interludes of both in traditional Gagok and in Sijo, combined with the interlude of the modern Gagok. It shows that the modern Gagok is affected on both the traditional Gagok and the Sijo. In addition, it explains elements of ADanSungJang - - tones and sounds in the modern Gagok. Originally, the traditional Gagok and sijo are composed of tones and sounds. At this point, tones are short, whereas sounds should be longer. This kind of way in the song has appeared on the modern Gagok of Hong, Nan-Pa. Lastly, the factors is about changing verses of modern Gagok. The one of differences between the modern Sijo and traditional Sijo is verses. For example, when it comes to sijo by Lee, Eun-Sang, he used to create his sijo with three verses. Hence, he did not change verses on his works. Whereas, the modern song "The Spring Lady" by Hong, Nan-Pa has shown the phenomenon that is separating three verses into six verses. It is noticeable that this phenomenon in "The Spring Lady" has the same bases with the modern Sijo.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.11-18
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• 2014

Most of the energy efficient MAC protocols for wireless sensor networks (WSNs) are based on duty cycling in a single channel and show competitive performances in a small number of traffic flows; however, under concurrent multiple flows, they result in significant performance degradation due to contention and collision. We propose a multi-channel pipelining (MCP) method for convergecast WSN in order to address these problems. In MCP, a staggered dynamic phase shift (SDPS) algorithms devised to minimize end-to-end latency by dynamically staggering wake-up schedule of nodes on a multi-hop path. Also, a phase-locking identification (PLI) algorithm is proposed to optimize energy efficiency. Based on these algorithms, multiple flows can be dynamically pipelined in one of multiple channels and successively handled by sink switched to each channel. We present an analytical model to compute the duty cycle and the latency of MCP and validate the model by simulation. Simulation evaluation shows that our proposal is superior to existing protocols: X-MAC and DPS-MAC in terms of duty cycle, end-to-end latency, delivery ratio, and aggregate throughput.

• The KIPS Transactions:PartC
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• v.9C no.6
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• pp.823-830
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• 2002

Enterprise security management system proposed to properly manage heterogeneous security products is the security management infrastructure designed to avoid needless duplications of management tasks and inter-operate those security products effectively. In this paper, we propose the model of generalized security policies. It is designed to help security management build invulnerable security policies that can unify various existing management infrastructures of security policies. Its goal is not only to improve security strength and increase the management efficiency and convenience but also to make it possible to include different security management infrastructures while building security policies. In the generalization process of security policies. we first diagnose the security status of monitored networks by analyzing security goals, requirements, and security-related information that security agents collect. Next, we decide the security mechanisms and objects for security policies, and then evaluate the properness of them on the basis of security goals, requirements and a policy list. With the generalization process, it is possible to integrate heterogeneous security policies and guarantee the integrity of them by avoiding conflicts or duplications among security policies. And further, it provides convenience to manage many security products existing in large networks.

• The KIPS Transactions:PartA
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• v.16A no.2
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• pp.69-78
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• 2009

One of the most effective way to improve cache performance is to exploit both temporal and spatial locality given by any program executive characteristics. In this paper we present a high performance and low power cache structure with a bank selection mechanism that enhances exploitation of spatial and temporal locality. The proposed cache system consists of two parts, i.e., a main direct-mapped cache with a small block size and a fully associative buffer with a large block size as a multiple of the small block size. Especially, the main direct-mapped cache is constructed as two banks for low power consumption and stores a small block which is selected from fully associative buffer by the proposed bank selection algorithm. By using the bank selection algorithm and three state bits, We selectively extend the lifetime of those small blocks with high temporal locality by storing them in the main direct-mapped caches. This approach effectively reduces conflict misses and cache pollution at the same time. According to the simulation results, the average miss ratio, compared with the Victim and STAS caches with the same size, is improved by about 23% and 32% for Mibench applications respectively. The average memory access time is reduced by about 14% and 18% compared with the he victim and STAS caches respectively. It is also shown that energy consumption of the proposed cache is around 10% lower than other cache systems that we examine.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.8
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• pp.287-300
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• 2021

Collaborative Cyber-Physical Systems (CCPS) are those systems that contain tightly coupled physical and cyber components, massively interconnected subsystems, and collaborate to achieve a common goal. The safety of a single Cyber-Physical System (CPS) can be achieved by following the safety standards such as ISO 26262 and IEC 61508 or by applying hazard analysis techniques. However, due to the complex, highly interconnected, heterogeneous, and collaborative nature of CCPS, a fault in one CPS's components can trigger many other faults in other collaborating CPSs. Therefore, a safety assurance technique based on fault criticality analysis would require to ensure safety in CCPS. This paper presents a Fault Criticality Matrix (FCM) implemented in our tool called CPSTracer, which contains several data such as identified fault, fault criticality, safety guard, etc. The proposed FCM is based on composite hazard analysis and content-based relationships among the hazard analysis artifacts, and ensures that the safety guard controls the identified faults at design time; thus, we can effectively manage and control the fault at the design phase to ensure the safe development of CPSs. To justify our approach, we introduce a case study on the Platooning system (a collaborative CPS). We perform the criticality analysis of the Platooning system using FCM in our developed tool. After the detailed fault criticality analysis, we investigate the results to check the appropriateness and effectiveness with two research questions. Also, by performing simulation for the Platooning, we showed that the rate of collision of the Platooning system without using FCM was quite high as compared to the rate of collisions of the system after analyzing the fault criticality using FCM.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.10
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• pp.1331-1340
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• 2020

Object detection in maritime means that the captain detects floating objects that has a risk of colliding with the ship using the computer automatically and as accurately as human eyes. In conventional ships, the presence and distance of objects are determined through radar waves. However, it cannot identify the shape and type. In contrast, with the development of AI, cameras help accurately identify obstacles on the sea route with excellent performance in detecting or recognizing objects. The computer must calculate high-volume pixels to analyze digital images. However, the CPU is specialized for sequential processing; the processing speed is very slow, and smooth service support or security is not guaranteed. Accordingly, this study developed maritime object detection software and implemented it with FPGA to accelerate the processing of large-scale computations. Additionally, the system implementation was improved through embedded boards and FPGA interface, achieving 30 times faster performance than the existing algorithm and a three-times faster entire system.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.6
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• pp.275-284
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• 2023

Virtual reality simulations are used for education and training in various fields, and are especially widely used in the medical field recently. The education/training simulator consists of tactile/force feedback generation and image/sound output hardware that provides a sense similar to a doctor's treatment of a real patient using real surgical tools, and software that produces realistic images and tactile feedback. Existing simulators are complicated and expensive because they have to use various types of hardware to simulate various surgical instruments used during surgery. In this paper, we propose a dental surgical simulation system using a force feedback device and a morphable haptic controller. Haptic hardware determines whether the surgical tool collides with the surgical site and provides a sense of resistance and vibration. In particular, haptic controllers that can be deformed, such as length changes and bending, can express various senses felt depending on the shape of various surgical tools. When the user manipulates the haptic feedback device, events such as movement of the haptic feedback device or button clicks are delivered to the simulation system, resulting in interaction between dental surgical tools and oral internal models, and thus haptic feedback is delivered to the haptic feedback device. Using these basic techniques, we provide a realistic training experience of impacted wisdom tooth extraction surgery, a representative dental surgery technique, in a virtual environment represented by sophisticated three-dimensional models.