http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Mathematical Description of Deformation of Micro Convex Body on Rough Surface
Youkun Zhong 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.5
Friction and wear process is due to the interaction of the relative motion between friction pair surfaces. Problems of rough surface and contact mechanics are not just appeared in tribology, but they have close relationship with friction or tribology and they are the necessary problem to solve in understanding of friction and wear phenomena. In the paper, we make the assumption of deformation continuity and smoothness of the surface asperity and combined with related theory to establish a mathematical model for the calculation for surface contact. The model is verified with a specified example. The results have been calculated and compared with results of other models. The comparison results show that the calculation model established in this paper has small error when the load is small load but with big difference with test results when the load is higher. The model can be used in the research of influence factors of real contact area of sliding friction surface, but it should take actual factors into consideration.
안유근(Youkun Ahn),형남철(Namcheol Hyeong),김광섭(Kwangsub Kim),김민호(Minho Kim),김규상(Kyusang Kim),박희석(Heeseok Park) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11
The appearance and signature of a given vehicle defined by dedicated lighting equipment were and are still today very important topic to develop a competitive vehicle. Automotive lighting devices, as with other lighting apparatus, should show low power consumption, long life time and new stylish design. Light Emitting Diode (LED) light sources, which are compact and adjustable in correlated color temperature (CCT), provide the best potential to realize these requirements. As LEDs are still an evolving technology, mature and fixed technical solutions were and are not always existed. The size and shape of LED chips are dependent on the regulation of automotive headlamp. The reliability of chip itself is the main factor to fulfill the performance of light source. The development of a related ceramic based package (PKG) was focused on the heat dissipation and the maximum optical power. The heat generated by LEDs increases the temperature of the environment and deteriorates the performance of LEDs. The phosphor coating techniques are related to the light source dimensions and CCT.
Z-함수를 이용한 순위패턴매칭과 순위다중패턴매칭 병렬계산
신유건(Youkun Shin),김영호(Youngho Kim),심정섭(Jeong Seop Sim) 한국정보과학회 2018 정보과학회논문지 Vol.45 No.8
순위패턴매칭문제는 길이가 각각 n, m 인 텍스트 T와 패턴 P가 주어졌을 때, P와 순위동형인 T의 모든 부분문자열의 위치를 찾는 문제이다. 순위다중패턴매칭문제는 길이가 n인 텍스트 T와 패턴 집합 W={P₁, P₂,…, Pb}가 주어졌을 때 W의 패턴들과 순위동형인 T의 모든 부분문자열의 위치를 찾는 문제이다. 본 논문에서는 Z-함수를 기반으로, 순위패턴매칭문제를 O(n+hm)개의 스레드를 사용하여 O(m) 시간에 해결하는 병렬알고리즘과 순위다중패턴매칭문제를 O(b(n+M))개의 스레드를 사용하여 O(n+M) 시간에 해결하는 병렬알고리즘을 제시한다. 이때, h는 블록의 개수이며, M은 W에서 가장 긴 패턴의 길이를 나타낸다. 실험 결과, 순위패턴매칭문제에 대한 병렬알고리즘은 순차알고리즘보다 m=10, n=1,000,000일 때 약 71.2배 빠르게 수행되었다. 또한 순위다중패턴매칭문제에 대한 병렬알고리즘은 b=1,000, m=10, n=1,000일 때 순차알고리즘보다 약 12.2배 빠르게 수행되었다. Given a text T of length n and a pattern P of length m, the order-preserving pattern matching problem is to find all substrings in T which are order-isomorphic to P. Given a text T of length n and a set of patterns W={P₁, P₂,…, Pb}, the order-preserving multiple pattern matching problem is to find all substrings in T which are order-isomorphic to patterns of W. In this paper, we present two parallel algorithms based on the Z-function. The first algorithm for the order-preserving pattern matching problem runs in O(m) time using O(n+hm) threads and the second algorithm for the order-preserving multiple pattern matching problem runs in O(n+M) time using O(b(n+M)) threads, where h is the number of blocks and M is the length of the longest pattern in W. Experimental results show that our parallel algorithm for the order-preserving pattern matching problem is approximately 71.2 times faster than the sequential algorithm when m=10 and n=1,000,000, and that our parallel algorithm for the order-preserving multiple pattern matching problem is approximately 12.2 times faster than the sequential algorithm when b=1,000, m=10, and n=1,000.
Xiliang Liu,Song Liu,Youkun Fan,Jin Qi,Xin Wang,Wei Bai,Dongliang Chen,Chengdong Xiong,Lifang Zhang 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.104 No.-
The poly(L-lactide-co-e-caprolactone) (PLCL) ureteral stent creeps and loses shape stability, increasingthe risk of stent tube dislocation. The rubbery biodegradable cross-linked PLCL networks were preparedthrough gamma irradiation under vacuum in the presence of trimethylolpropane triacrylate (TMPTA),pentaerythritol tetraacrylate (PET4A), and pentaerythritol triacrylate (PETA). At a standard sterilizationdose of 25 kGy, the gel content and network density of PLCL networks increased with increasingcrosslinking agent content (1, 3, 5, 7 wt%), and crosslinking efficiency decreased in the order ofPETA > PET4A > TMPTA. The average molecular weight (Mc ) between two crosslinks ranged from 2000to 105 g/mol. To perform the beneficial semi-interpenetrated polymer network and characterized bythe principle, the networks were processed in several doses (25, 50, 75, 100, and 125 kGy). In place ofthe Charlesby-Pinner equation, the irradiation cross-linking followed the Chen-Liu-Tang equation. ThePLCL network with 7 wt% PETA had a gel fraction of 83%, tensile strength of 34.7 MPa, and tensile setvalue as low as 5%. Furthermore, degradation in vitro was slowed down. Thus, PLCL networks with appropriateelasticity and flexibility, inherent biodegradability, and excellent biocompatibility can provide apromising alternative method for soft tissue repair engineering, such as ureteral stents.
이재홍(Jaehung Lee),박용수(Youngsu Park),이영기(Youngki Lee),조유근(Youkun Cho) 한국정보과학회 2003 한국정보과학회 학술발표논문집 Vol.30 No.1A
침입 탐지 시스템에 이상 탐지 기법(anormal detection)을 적용할 때 정상적인 시스템호출 순서에 대한 훈련이 필요하다. 이 때 발생하는 가장 큰 문제점중 하나는 침입 없는 훈련 데이터의 확보이다. 훈련 데이터의 침입이 있으면 이 침입을 정상으로 간주해서 이후에 같은 침입이 일어나도 이를 탐재해 내지 못하기 때문이다. 하지만, 침입 없는 훈련 데이터를 얻는 것은 매우 어렵다. 본 논문에서는 훈련 데이터의 침입이 포함되어 있더라도 효과적으로 침입을 탐지할 수 있는 시스템 호출 기반 침입 탐지 기법을 제안한다. 제안 기법은 훈련 데이터의 침입이 존재할 경우 침입 부분에서 빈도가 매우 적은 데이터들이 연속적으로 나타나는 성질을 이용한다. 이를 위해 훈련 데이터를 일정 개수씩 블록으로 묶은 뒤 평균 빈도를 계산해서 그 값이 임계치보다 작은 경우 이를 침입 데이터로 간주하여 훈련 데이터에서 제외하는 방법을 사용하였다. 실험 결과 블록 크기를 적절하게 잡았을 경우 기존의 Eskin 기법보다 향상된 결과를 얻을 수 있었다.
Design of Shield Blanket Near NB Port and Development of Be/Cu Joining for ITER
Fu Zhang,Elio Filippo,Jiming Chen,Weishan Kang,Youkun Fu 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.III
The design of two shield blanket modules near the neutral beam (NB) port was developed at Southwestern Institute of Physics (SWIP) in collaboration with the ITER International Team. Some results are given in this paper. The HIP technology for Be/Cu joining in the first wall is being qualified at SWIP and it is also introduced.
주종현(Junghyun Joo),이충우(Chungwoo Lee),강병도(Byungdo Kang),배성효(Sunghyo Bai),안유근(Youkun Ahn),박종배(jongbai Park) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
It became necessary to develop multi-function interior lamps rather than single-function interior lamp, since people tend to drive longer and spend more time in their cars at nighttime. A total interior lamp system was developed after the positions and emotional states of occupants were taken into consideration. To operate the Total Interior Lamps system with ease a multi-function dial switch was developed.