• 대한기계학회논문집A
• /
• 제27권5호
• /
• pp.681-687
• /
• 2003

Terrain surfaces have to be modeled in very detail and wheel-surface contacting geometry must be well defined in order to obtain proper ground-reaction and friction forces fur realistic simulation of off-road vehicles. Delaunay triangulation is one of the most widely used methods in modeling 3-dimensional terrain surfaces, and the T-search is a relevant algorithm for searching resulting triangular polygons. The T-search method searches polygons in a successive order and may not allow real-time computation of off-road vehicle dynamics if the terrain is modeled with many polygons, depending on the computer performance used in the simulation. The dynamic T-search, which is proposed in this paper, combines conventional T-search and the concept of the dynmaic-window search which uses reduced searching windows or sets of triangular surface polygons at each frame by taking advantage of the information regarding dynamic charactereistics of a simulated vehicle. Numerical tests show improvement of searching speeds by about 5% for randomly distributed triangles. For continuous search following a vehicle path, which occurs in actual vehicle simulation, the searching speed becomes 4 times faster.

• 한국간호교육학회지
• /
• 제18권3호
• /
• pp.393-402
• /
• 2012

Purpose: This study was conducted to test the effect of a Career Search Program on career search efficacy, career search behavior, and career decision making for nursing students. Methods: A non-equivalent pre-post test of a quasi-experimental design was used. Fifty first grade nursing students participated in the study with 22 in the experimental group and 28 in the control group. We used a Career Search Program which was held 6 times over 6 weeks, 90 minutes per session. Descriptive statistics, ${\chi}^2$-test, and independent t-test were used for statistical analysis with SPSS 19.0. Results: There were significant increases in career search efficacy (t=2.07, p=.044) and career search behavior(t=2.65, p=.011) in the experimental group compared to the control group. However, career decision making was not significantly changed (t=0.96, p=.342). Conclusion: These results suggest that a Career grade Search Program has an effect on increasing career search efficacy and career search behavior in first grade nursing students. In addition, more programs to impact career decision making should be developed for nursing college students.

• 전기학회논문지
• /
• 제65권1호
• /
• pp.128-134
• /
• 2016

IoT devices including smart devices are connected with internet, thus they have security threats everytime. Particularly, IoT devices are composed of low performance MCU and small-capacity memory because they are miniaturized, so they are likely to be exposed to various security threats like DoS attacks. In addition, in case of IoT devices installed for a remote place, it's not easy for users to control continuously them and to install immediately security patch for them. For most of IoT devices connected directly with internet under user's intention, devices exposed to outside by setting IoT gateway, and devices exposed to outside by the DMZ function or Port Forwarding function of router, specific protocol for IoT services was used and the devices show a response when services about related protocol are required from outside. From internet search engine for IoT devices, IP addresses are inspected on the basis of protocol mainly used for IoT devices and then IP addresses showing a response are maintained as database, so that users can utilize related information. Specially, IoT devices using HTTP and HTTPS protocol, which are used at usual web server, are easily searched at usual search engines like Google as well as search engine for the sole IoT devices. Ill-intentioned attackers get the IP addresses of vulnerable devices from search engine and try to attack the devices. The purpose of this study is to find the problems arisen when HTTP, HTTPS, CoAP, SOAP, and RestFUL protocols used for IoT devices are detected by search engine and are maintained as database, and to seek the solution for the problems. In particular, when the user ID and password of IoT devices set by manufacturing factory are still same or the already known vulnerabilities of IoT devices are not patched, the dangerousness of the IoT devices and its related solution were found in this study.

• 한국산학경영학회:학술대회논문집
• /
• 한국산학경영학회 2005년도 추계학술발표대회 발표논문집
• /
• pp.1-9
• /
• 2005

Job search research has been criticized for failing to study the dynamics and change of the job search process. A lot of previous researches have used cross-sectional designs and treated job search as a static process. As a result, job search research has failed to examine how job seekers' behaviors change during the course of their search. This paper examined changes In job search behaviors(preparatory and active job search behavior, and job search intensity) and the effects of individual difference variables(self-esteem, self-efficacy, extroversion, agreeableness, conscientiousness, openness) on job search behaviors. Data were gathered from 404 university students who had not found employment at the time of beginning of second semester The results of t-test pairs indicated that job seeking students increased their preparatory job search behavior and active job search behavior, but didn't job search intensity. The results of multiple regression showed that self-efficacy had strong relationship with preparatory and active job search behavior, and job search intensity, but self-esteem had not any relationship with them. Among big-5 personality, extroversion had relationship with active job search behavior and job search intensity, and agreeableness only with job search intensity.

• 한국시뮬레이션학회:학술대회논문집
• /
• 한국시뮬레이션학회 2002년도 추계학술대회 논문집
• /
• pp.163-170
• /
• 2002

Terrain surfaces have to be modeled in very detail and wheel-surface contacting geometry must be well defined in order to obtain proper ground-reaction and friction forces for realistic simulation of off-road vehicles. Delaunay triangulation is one of the most widely used methods in modeling 3-dimensional terrain surfaces, and T-search is a relevant algorithm for searching resulting triangular polygons. The T-search method searches polygons in successive order and may not allow real-time computation of off-road vehicle dynamics if the terrain is modeled with many polygons, depending on the computer performance used in the simulation. In order to accelerate the searching speed of T-search, a terrain database of triangular polygons is modeled in multi-levels by adopting the LOD (Level of Detail) method used in realtime computer graphics. Simulation results show that the new LOD search is effective in shortening the required computing time. The LOD search can be even further accelerated by introducing an NN (Neural Network) algorithm, in the cases where a appropriate range of moving paths can be predicted by cultual information of the simulated terrain, such as lakes, houses, etc.. Numerical tests show that LOD-NN search almost double the speed of the original T-search.

• 정보관리연구
• /
• 제37권4호
• /
• pp.25-47
• /
• 2006

다국어로 구축된 학술정보 시스템의 통합검색 환경을 구현하기 위해서는 다국어 전문용어에 대한 해석을 제공하고 전문용어의 분야별 분류정보를 제공할 수 있는 시스템이 필요하다. 본 연구는 이러한 다국어 환경의 통합 정보검색 시스템을 운용할 수 있도록 기반시스템을 구축하는 것을 목적으로 한다. 다국어 의미망으로 상호 연결된 과학기술 전문용어 체계를 구축하는 방법과 다단계 연결노드에 대한 최단거리 탐색 기법을 소개하였다. 또한, 생성된 용어군집 결과를 해석하기 위한 기초분석을 수행하여 향후 심도있는 분석연구를 수행하기 위한 기반을 마련하고자 하였다.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2006년도 가을 학술발표논문집 Vol.33 No.2 (A)
• /
• pp.153-157
• /
• 2006

기존의 탐색 알고리즘은 탐색 창 내의 원점에서 탐색을 시작한다. 하지만 영상은 일정한 방향으로 규칙적으로 움직이는 것이 많기 때문에 Frame$_t$ 의 움직임 벡터(MV)가 Frame$_{t-1}$의 움직임 벡터와 같을 가능성이 크다. 이를 참고하여 본 논문에서는 시작점을 원점뿐만 아니라 Frame$_{t-1}$의 MV까지도 예측 시작점으로 선택하여 탐색의 시작점을 다양화 하였다. 실험 결과 탐색 시작점을 다양화 함으로써 full search를 제외한 diamond search, hexagonal search, 4 step search등 기존의 탐색 알고리즘보다 30$\sim$80% 더 작은 SAD값을 구할 수 있었다.

• 한국정보과학회논문지:시스템및이론
• /
• 제29권2호
• /
• pp.87-93
• /
• 2002

주어진 스트링 S의 접미사트리 $T_s$를 구축하기 위하여 , 먼저 홀수위치들에 대한 접미사트리 $ T_0$를 제귀적으로 구축하고 짝수위치들에 대한 접비사트리 $T_e$를 $ T_o$/로 부터 구축한 다음 $ T_o$와 $T_e$를 합병하여 $T_s$를 구축하는 새로운 방식이 사용되고 있다. 인덱스자료구조에 관련된 문제들 중 정수 문자집합상의 접미사트리를 선형시간에 구축하는 문제는 오랫동안 미해결문제로 남아 있었다. Farach은 이 방식을 적용하여 처음으로 성형시간이 소요되는 알고리즘을 제시하였다. 이 알고리즘은 중 가장 어려운 곳은 합병하는 부분이다. 본 논문에서는 BFS(breadth-first search)에 기반하는 새로운 합병알고리즘을 제안한다. 제안된 합병알고리즘은 Farach의 DFS(depth-first search) 방식보다 개념적으로 단순하게 동작하므로 다른 응용의로 쉽게 확장될수 있다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제13권11호
• /
• pp.5692-5716
• /
• 2019

One of the best means to safeguard the confidentiality, security, and privacy of an image within the IoT-Cloud is through encryption. However, looking through encrypted data is a difficult process. Several techniques for searching encrypted data have been devised, but certain security solutions may not be used in IoT-Cloud because such solutions are not lightweight. We propose a lightweight scheme that can perform a content-based search of encrypted images, namely EEIRI. In this scheme, the images are represented using local features. We develop and validate a secure scheme for measuring the Euclidean distance between two descriptor sets. To improve the search efficiency, we employ the k-means clustering technique to construct a searchable tree-based index. Our index construction process ensures the privacy of the stored data and search requests. When compared with more familiar techniques of searching images over plaintexts, EEIRI is considered to be more efficient, demonstrating a higher search cost of 7% and a decrease in search accuracy of 1.7%. Numerous empirical investigations are carried out in relation to real image collections so as to evidence our work.

• 한국자기학회지
• /
• 제20권5호
• /
• pp.178-181
• /
• 2010

탐지코일 마그네토미터는 고감도의 교류자기장 측정용으로 많이 사용되어 왔다. 본 연구에서는 센서코어의 자기소거인자를 감소시키고, 센서의 S/N ratio를 증가시키기 위하여 코어를 2개로 분리하고 각각의 코어에 코일을 권선하였으며, 코일의 연결은 차동형이 되게 하였다. 제작된 탐지코일 마그네토미터의 선형도는 0.03 % 이였으며, 감도가 9.3 mV/nT이고, 분해능은 1 Hz에서 20 pT 정도였다.