• 로봇학회논문지
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• 제14권4호
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• pp.270-277
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• 2019

Inspired by small insects, which perform rapid and stable locomotion based on body softness and tripod gait, various milli-scale six-legged crawling robots were developed to move rapidly in harsh environment. In particular, cockroach's leg compliance was resembled to enhance the locomotion performance of the crawling robots. In this paper, we investigated the effects of changing leg compliance for the locomotion performance of the small light weight legged crawling robot under various payload condition. First, we developed robust milli-scale six-leg crawling robot which actuated by one motor and fabricated in SCM method with light and soft material. Using this robot platform, we measured the running velocity of the robot depending on the leg stiffness and payload. In result, there was optimal range of the leg stiffness enhancing the locomotion ability at each payload condition in the experiment. It suggests that the performance of the crawling robot can be improved by adjusting stiffness of the legs in given payload condition.

• 한국자동차공학회논문집
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• 제19권2호
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• pp.133-141
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• 2011

The effect of payload on fuel consumption and emission of light duty freight truck during acceleration driving has been analyzed. Running tests were carried out with various payload conditions on chassis dynamometer. A typical driving pattern for urban cities was used. Real time emission measurement systems for gaseous and soot emission were utilized to investigate the real time dynamic of fuel use and exhaust emissions. It was observed that fuel use and pollutant emissions were increased as payload was increased. Under the same payload condition, the increased amount of acceleration driving is much higher than that of steady state driving. The results demonstrated the advantages of eco-driving, which is an environmentally friendly driving manner, could be emphasized in heavier payload condition. Inertial tractive power was introduced for considering the parameters affecting emission during acceleration driving, which are speed, acceleration and payload. Fuel use and emission in various driving conditions were expressed as functions of inertial tractive power. The estimated result by these functions well predicted measured result within 10 % deviation.

• 대한교통학회지
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• 제29권2호
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• pp.25-35
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• 2011

도로물류부문의 온실가스 저감 및 물류체계를 효율화하기 위해서는 화물차의 운행효율화가 무엇보다 중요하다. 효율적인 수송체계의 구축은 화물차의 적재효율 향상, 수송수단의 전환 등을 통하여 온실가스 저감 및 수송비용을 절감할 수 있다. 또한, 물류부문의 환경부하량을 감축하기 위해서는 환경부하를 정량적으로 파악할 수 있어야 한다. 하지만, 국내 물류기업의 환경부하에 대한 체계적인 조사가 미비한 실정이다. 본 연구에서는 국내 물류부문의 화물환경지표로 화물수송실적(ton km) 당 $CO_2$ 배출량으로 설정하였다. 여기서, 화물수송실적(ton km) 당 $CO_2$ 배출량은 1 ton의 화물을 1 km 수송할 때 배출되는 $CO_2$ 양이다. 국내 물류기업을 대상으로 분석한 결과와 영국, 프랑스의 화물수송실적 당 CO2 배출량을 비교하면 국내 업체가 $363g-CO_2/ton{\cdot}km$로 영국 $130g-CO_2/ton{\cdot}km$에 비해 2.8배, 프랑스 $97g-CO_2/ton{\cdot}km$로 3.7배 높게 배출되는 것으로 나타났다. 이는 영국과 프랑스에 비해 국내 화물차의 공차 운행율이 높고, 적재 효율은 낮은 것이 주요 원인으로 판단된다.

• 한국정보통신학회논문지
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• 제22권5호
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• pp.794-804
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• 2018

컴퓨터에서 실행되는 다양한 응용들은 네트워크를 통해 패킷 형태로 정보를 전달하며 대부분의 패킷들은 TCP/IP 또는 UDP/IP 프로토콜을 따른다. 기업 및 기관의 네트워크 관리 담당자는 네트워크 트래픽 측정 및 감시, 네트워크 보안 등을 위해서 네트워크를 통해 전달되는 패킷들을 지속적으로 관리할 수 있어야 한다. 본 논문에서는 실제 전달되는 데이터를 면밀히 조사하는 DPI(Deep Packet Inspection)에서 페이로드의 특정 패턴을 검색하는 패킷 페이로드 분석 알고리즘들의 성능 분석하는 것을 목적으로 하고 있다. 페이로드를 조사하는 가장 기본적인 과정은 특정 패턴을 페이로드에서 신속하게 검색하는 것이다. 본 논문에서는 페이로드에 특정 패턴이 존재하는 경우, 그 패턴을 검출할 수 있는 여러 알고리즘들을 소개하고, 세 가지 관점에서 수학적으로 성능을 분석하고, 응용프로그램의 목적에 적합한 적용 방안을 제시한다.

• 대한조선학회논문집
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• 제43권1호
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• pp.134-146
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• 2006

This paper presents the primary conceptual design results of twenty-passenger class Wing-In-Ground(WIG) effect craft. As a first step, top level requirements were proposed and principal dimensions were determined. Maximum speed in ground effect condition is 150 km/h with two tons payload including passengers. Total weight is estimated as 8.5 tons with 2 tons of thrust. Hull and airfoil sections were designed and self propulsion tests were performed by radio controlled model. Two planing hull forms with the transom stern were proposed and towing tests were performed. The resistance and running attitude were measured and the feasibility is checked for the prototype hull form of the twenty-passenger class WIG craft. The free running tests show the stable smooth running attitude at designed speed. Also this radio controlled model can take off around 0.15 meter wave height. It can be said that the top level requirement for the twenty passenger class WIG ship is satisfied successfully. The design optimization to increase the transport efficiency and safety will be performed in the near future.

• Advances in aircraft and spacecraft science
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• 제2권1호
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• pp.17-44
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• 2015

A modular multidisciplinary analysis and optimization framework has been built with the goal of performing conceptual design of an advanced efficient supersonic air vehicle. This paper addresses the specific challenge of designing this type of aircraft for a long range, supersonic cruise mission with a payload release. The framework includes all the disciplines expected for multidisciplinary supersonic aircraft design, although it also includes disciplines specifically required by an advanced aircraft that is tailless and has embedded engines. Several disciplines have been developed at multifidelity levels. The framework can be readily adapted to the conceptual design of other supersonic aircraft. Favorable results obtained from running the analysis framework for a B-58 supersonic bomber test case are presented as a validation of the methods employed.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.171-174
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• 2007

The COMS flight software is implemented by ADA language and the high level application program language (APL). The APL is used to implement the Interpreted Program (IP) functions which are running on the processor. The IP functions have been developed for the payload management and monitoring with the automatic on-board operational procedure. The IP allows an easier re-programming if necessary. The ground can load or unload IP separately from ADA code in the RAM flight software. The uploaded IP is interpreted and executed by the Interpreted Program Environment (IPE) which is one of the functions implemented in the RAM flight software. In this paper, we introduce the IP and IPE function.

• International Journal of Automotive Technology
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• 제7권3호
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• pp.269-276
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• 2006

Running tests on roads were conducted to clarify the influences of road infrastructure, traffic condition and vehicle's emission level to the amount of emission at local roadsides, and to reveal the operation patterns which can reduce the emission peaks. NOx emission peaks of two light duty freight diesel vehicles which have different emission levels were evaluated by using an on-board measurement system. Tests were carried out with various payload conditions and road conditions. As a result many NOx emission peaks were observed when the vehicles were starting or accelerating at intersections. The test vehicle which has higher emission level caused higher frequency and level of NOx emission peaks. Shifting up at lower engine speed in combination with lower acceleration brought out not only reduction of NOx emission peaks level but also of $CO_2$ mass emission.

• 정보처리학회논문지C
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• 제11C권3호
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• pp.319-326
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• 2004

많은 공격과 네트워크 데이터 처리량이 증가하는 오늘날의 네트워크 수요를 NIDS가 유지시키기 위해 하드웨어 및 소프트웨어 시스템 구조에서 급진적 새로운 접근이 필요하다. 본 논문에서는 패킷 필터링과 트래픽 측정 뿐아니라 고의행위를 검출하는 패킷 페이로드 검열을 지원하는 네트워크 프로세서 기반의 인라인 모드 NIS를 제안하고, 특히 2한계 경색구조를 사용하여 심층 패킷 정열기능으로부터 펄터링과 측정기능을 분리한다 그래서 심층 패킷 검열기능의 복잡하고 시간소비 곽이 인라인 모드 시스템의 기본 기능을 멈추게 하거나 방해하지 않게 했다. 프로토타입 NP 기반의 NIDS는 PC 플랫폼에서 구현하였으므로 실험결과는 제안한 구조가 첫 단계에서 두개의 기가비트 포트의 전체 트래픽을 측정과 필터가 신뢰할 수 있음을 보였다. 일반목적 프로세스 기만의 검열 성능과 비교 가능한 두 번째 단계에서 실시간으로 320Mbps까지 패킷 페이로드를 주사할 수 있었다. 그러나 시뮬레이션에서 100bps APP 해법을 선택할 때 선로상 속도가 2Gbps까지 가능한 심층 패킷 검색 결과를 얻었다.