• 제어로봇시스템학회논문지
• /
• 제19권6호
• /
• pp.513-519
• /
• 2013

The current vision-based approaches for emotion recognition, such as facial expression analysis, have many technical limitations in real circumstances, and are not suitable for applications that use them solely in practical environments. In this paper, we propose an approach for emotion recognition by combining extrinsic representations and intrinsic activities among the natural responses of humans which are given specific imuli for inducing emotional states. The intrinsic activities can be used to compensate the uncertainty of extrinsic representations of emotional states. This combination is done by using PRMs (Probabilistic Relational Models) which are extent version of bayesian networks and are learned by greedy-search algorithms and expectation-maximization algorithms. Previous research of facial expression-related extrinsic emotion features and physiological signal-based intrinsic emotion features are combined into the attributes of the PRMs in the emotion recognition domain. The maximum likelihood estimation with the given dependency structure and estimated parameter set is used to classify the label of the target emotional states.

• 보건교육건강증진학회지
• /
• 제6권2호
• /
• pp.58-65
• /
• 1989

This study analyzes the structural characteristics of rapid changes in Korean population, using the data of a census and other data on the changes in the population. Major findings are : 1. During 1950~1955, annual increase rate of population was about 1.02%, about 2.88% during 1955~1960, and 1.36% during 1980~1985. It is expected to decrease to 0.07% during 2015~2020. 2. Major Age Composition 0~14 is expected to reduce to 16.5% in 2020 from 41.2% in 1955, while the ratio of population aged 15~64 is expected to increase to 72.1% from 55.5%. Furthermore, for the population group of age 65 and over is expected to increase from a mere 3.3% to 11.4%. 3. The aging index of population is expected to increase to 69.5 in 2020 from 8.0 in 1955 and so the old dependency ratio is expected to 15.9 from 6.0 4. The median age is expected to 40.2 in 2020 from 19.0 in 1955. 5. In 2020 the child-woman ratio is expected to reduce to 22.3 from 64.7 in 1955. 6. In 2020 the age index of 0~4 is expected to 57.4 from 169.4 in 1955, and the age index of 65~69 to 261.7 from 95.6 on the contrary.

• Smart Structures and Systems
• /
• 제3권4호
• /
• pp.405-422
• /
• 2007

A new hybrid damping technique for vibration reduction in flexible structures, wherein a combination of layers of hard passive damping alloys and active (smart) magnetostrictive material is used to reduce vibrations, is proposed. While most conventional vibration control treatments are based exclusively on either passive or active based systems, this technique aims to combine the advantages of these systems and simultaneously, to overcome the inherent disadvantages in the individual systems. Two types of combined damping systems are idealized and studied here, viz., the Noninteractive system and the Interactive system. Frequency domain studies are carried out to investigate their performance. Finite element simulations using previously developed smart beam elements are carried out on typical metallic and laminated composite cantilever beams treated with hybrid damping. The influence of various parameters like excitation levels, frequency (mode) and control gain on the damping performance is investigated. It is shown that the proposed system could be used effectively to dampen the structural vibration over a wide frequency range. The interaction between the active and passive damping layers is brought out by a comparative study of the combined systems. Illustrative comparisons with 'only passive' and 'only active' damping schemes are also made. The influence and the mode dependence of control gain in a hybrid system is clearly illustrated. This study also demonstrates the significance and the exploitation of strain dependency of passive damping on the overall damping of the hybrid system. Further, the influence of the depthwise location of damping layers in laminated structures is also investigated.

• 대한기계학회논문집B
• /
• 제27권9호
• /
• pp.1282-1289
• /
• 2003

Transport of a scalar quantity, such as chemical concentration or temperature, is important in many engineering applications and environmental flows. Here we report on results obtained from the large eddy simulations of flow and concentration fields inside the tank performed using a spectral multi-domain technique. The computations were driven by specifying the impeller-induced flow at the blade tip radius (Yoon et al.). This study focused on the concentration development at different molecular diffusivities in a stirred tank operated under turbulent conditions. The main objective of the work presented here is to study the large-scale mixing structure at different molecular diffusivities in a stirred tank by using the large eddy simulation. The time sequence of concentration and flow fields shows the flow dependency of the concentration development. The presence of spatial inhomogenieties is detailed by observing the time variation oflocal concentration at different positions.

• 대한기계학회논문집B
• /
• 제27권9호
• /
• pp.1290-1298
• /
• 2003

The stirred tank reactor is one of the most commonly used devices in industry for achieving mixing and reaction. Here we report on results obtained from the large eddy simulations of flow inside the tank performed using a spectral multi-domain technique. The computations were driven by specifying the impeller-induced flow at the blade tip radius. Stereoscopic PlY measurements (Hill et al. $^{(1)}$) along with the theoretical model of the impeller-induced flow (Yoon et al. $^{(2)}$) were used in defining the impeller-induced flow as superposition of circumferential, jet and tip vortex pair components. Large eddy simulation of flow in a stirred tank was carried out for the three different Reynolds numbers of 4000, 16000 and 64000. The effect of different Reynolds numbers is well observed in both instantaneous and time averaged flow fields. The instantaneous and mean vortex structures are identified by plotting an isosurfaces of swirling strength for all Reynolds numbers. The Reynolds number dependency of the non-dimensional eddy viscosity, resolved scale and subgrid scale dissipations is clearly shown in this study.

• 한국지역사회생활과학회지
• /
• 제28권2호
• /
• pp.191-201
• /
• 2017

This study compared and analyzed the structures of cooking recipes in order to identify the overall cooking method and develop an efficient method for analyzing cooking recipes. We present procedural texts using a flow graph, which can be referred to as a recipe tree, to represent cooking recipes and the database. A total of 110 kimchi jjigae recipes were identified and classified as 'portion', 'kinds of ingredients', and 'number of cooking deployment'. Recipes for two persons were the most common (43.6%), and 7-13 kinds of ingredients accounted for 50% of kimchi jjigae recipes. Kimchi presented the highest frequency at 78 cases, and pork showed the high frequency at 30 cases. To identify cooking deployment, step 6 was the highest, followed by step 5 (17.3%), step 7 (17.3%), step 4 (11.8%), and step 3 (9.1%). When analyzing the frequency of the relationship between ingredients and action in a recipe expression, Food (F) and Action by the chef (Ac) showed the highest rates at 11.29 and 12.30, respectively, in the cooking process. For frequencies of dependency relation expression in recipes, d-obj (direct object) was the highest at 13.56. The proposed method provides users more efficient and easier access to recipes suitable for their cooking skills.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2011년도 제40회 동계학술대회 초록집
• /
• pp.452-452
• /
• 2011

Using ab initio calculations, we reveal the origins of the extraordinarily increased electric conductivity of the LaAlO3/SrTiO3 interface. In both of the two (LaAlO3)m/ SrTiO3 heterojunction models (m=3, 5), the oxygen atoms in the cells were displaced toward the n-type interface and the Ti-centered octahedron structure was compressed along the [001] direction by the atomic reconstructions at the (LaAlO3)m/(SrTiO3)4 interfaces. As a result, the 3dxy orbital of the Ti atom was preferentially occupied due to the lowered energy state of the 3dxy orbital, which arises from the crystal field asymmetry. We reason that the extra electrons occupy the 3dxy orbital are accumulated at the interface by the displacement of the oxygen atoms. This accumulation contributes to the conductivity of the n-type interface. In addition, through a comparison of the atomic displacements and charge accumulation amounts between the two thickness models (m=3, 5), the thickness-dependency of the conductivity can be explained.

• 전자공학회논문지A
• /
• 제32A권2호
• /
• pp.57-65
• /
• 1995

The effects of device geometry and layout on high speed performance such as current gain outoff frequency(f$_{T}$) and maximum oscillation frequency(f$_{max}$) are of very improtant for the scaling-down of geterojunction bipolar transistors(HBT$_{s}$). In this paper AlGaAs/GaAs HBTs are fabricated by MBE epitaxial growth and conventional mesa process, and the experimental data of emitter-base geometru dependency of HBT performance are presented in order to provide the quantitative information for optimum device structure design. It is shown that f$_{T}$ and f$_{max}$ are inversely proportional to the emiter stripe width, while the low emitter perimeter/area ratio is better to f$_{T}$ and worse ot f$_{max}$. It is also demonstrated the f$_{T}$ and f$_{max}$ are highly improved by the emitter-base spacing reduction resulting in less parsitic effects. As the result f$_{T}$ of 42GHz and f$_{max}$ of 23GHz are obtained for fabricated HBT with emitter area of 3${\times}20^{\mu}m^{2}$ and E-B spacing of 0.2$\mu$m.m.m.

• 인터넷정보학회논문지
• /
• 제2권4호
• /
• pp.91-99
• /
• 2001

프로그램 수행시간의 대부분이 루프 구조에서 소비되고 있기 때문에 루프 구조를 가진 순차 프로그램에서 병렬성을 추출하는 연구들이 많이 행해지고 있고 그 연구들은 하나의 프로시저 내 루프 구조의 변환에 치중되고 있다. 그러나 대부분의 프로그램들은 프로시저 간 잠재된 병렬성을 가지고 있다. 본 논문에서는 프로시저 호출을 가진 루프에서 병렬성 추출 방식을 제안한다. 프로시저 호출을 포함하는 루프의 병렬화는 대부분 자료종속거리가 uniform 형태의 코드에서만 집중되었다. 본 논문에서는 자료종속거리가 uniform 코드, nonuniform 코드 그리고 복합된(complex) 코드를 가진 프로그램에서 적용 가능한 알고리즘을 제시하였으며, 제안된 알고리즘과 loop extraction, loop embedding 그리고 procedure cloning변환 방법을 CRAY-T3E로 성능 평가하였다. 성능평가 결과는 제안된 알고리즘이 효율적이라는 것을 보여준다.

• Structural Engineering and Mechanics
• /
• 제37권2호
• /
• pp.197-213
• /
• 2011

Concrete is a heterogeneous material exhibiting quasi-brittle behaviour. While homogenization of concrete is commonly accepted in general engineering applications, a detailed description of the material heterogeneity using a mesoscale model becomes desirable and even necessary for problems where drastic spatial and time variation of the stress and strain is involved, for example in the analysis of local damages under impact, shock or blast load. A mesoscale model can also assist in an investigation into the underlying mechanisms affecting the bulk material behaviour under various stress conditions. Extending from existing mesoscale model studies, where use is often made of specialized codes with limited capability in the material description and numerical solutions, this paper presents a mesoscale computational model developed under a general-purpose finite element environment. The aim is to facilitate the utilization of sophisticated material descriptions (e.g., pressure and rate dependency) and advanced numerical solvers to suit a broad range of applications, including high impulsive dynamic analysis. The whole procedure encompasses a module for the generation of concrete mesoscale structure; a process for the generation of the FE mesh, considering two alternative schemes for the interface transition zone (ITZ); and the nonlinear analysis of the mesoscale FE model with an explicit time integration approach. The development of the model and various associated computational considerations are discussed in this paper (Part 1). Further numerical studies using the mesoscale model for both quasi-static and dynamic loadings will be presented in the companion paper (Part 2).