• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09b
• /
• pp.1327-1328
• /
• 2006

Lanthanum oxide was introduced to molybdenum powder by liquid-liquid doping and liquid-solid doping respectively. Mo alloys were prepared by powder metallurgy technology. The size distribution and feature of dopant particles and the fractographs of Mo alloys were investigated by TEM and SEM respectively. The results indicated that liquid-liquid doping method is favorable for refining and dispersing $La_2O_3$ particles uniformly in matrix. Fracture toughness of Mo alloys prepared by liquid-liquid doping showed better results than that of liquid-solid doping. Furthermore, the influences of the size distribution of $La_2O_3$ on properties of Mo alloys was discussed by dislocation pile-up theory.

• Journal of Institute of Control, Robotics and Systems
• /
• v.21 no.8
• /
• pp.709-712
• /
• 2015

This paper will introduce the development case study about virtual-reality-based operation training system for steel making process. Steel making process consist iron making process to create liquid steel, pig iron, by reduction process, steel making process to make molten steel by refining, continuous casting process to make slab, and rolling process to make final product like coil, plate. This steel making process deals with liquid and solid products, so facilities of steel making process are very various and complicated. In addition, according to various customer requirements, the recycle of facilities and recipes changing have been fast. So the training for skilled operators is very important point. In this paper, we develop steel making training system based virtual reality for training skilled operator. This system consists of virtual machine, virtual HMI, and virtual control panel. And for fitting the characteristics of each process and increasing the education effectiveness, we develop dynamic methods like the method of dynamic education system configuration, initial facilities setup operation education system, and etc.

• ETRI Journal
• /
• v.38 no.5
• /
• pp.818-828
• /
• 2016

This paper proposes a reusable design for the merging process used in three-dimensional High Efficiency Video Coding (3D-HEVC), which can significantly reduce the implementation complexity by eliminating duplicated module redundancies. The majority of inter-prediction coding tools used in 3D-HEVC are utilized through a merge mode, whose extended merging process is based on built-in integration to completely wrap around the HEVC merging process. Consequently, the implementation complexity is unavoidably very high. To facilitate easy market implementation, the design of a legacy codec should be reused in an extended codec if possible. The proposed 3D-HEVC merging process is divided into the base merging process of reusing HEVC modules and reprocessing process of refining the existing processes that have been newly introduced or modified for 3D-HEVC. To create a reusable design, the causal and mutual dependencies between the newly added modules for 3D-HEVC and the reused HEVC modules are eliminated, and the ineffective methods are simplified. In an application of the proposed reusable design, the duplicated reimplementation of HEVC modules, which account for 50.7% of the 3D-HEVC merging process, can be eliminated while maintaining the same coding efficiency. The proposed method has been adopted as a normative coding tool in the 3D-HEVC international standard.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.17 no.2
• /
• pp.282-288
• /
• 2014

In this research, we investigated synthetic method of 2,6-DANT that can be used as a chain extender of urethane/urea and epoxy materials in a demilitarization method via chemical transformations considering environmental, economical aspects and stability of process. We was able to identify through GC monitoring that 2,4-DANT and 2,6-DANT were produced when we inject 'hydrazine monohydrate 3.3 eq. by TNT 1 eq.' with a fine metering pump for 30 minutes and then, reflux for an additional 2 hours. We was able to isolate only 2,6-DANT(99.3% purity and 45.0% yield) from mixture of 2,4-DANT and 2,6-DANT through the separating and refining methods using 2,6-DANT solubility in methanol and crystallinity of 2,6-DANT.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.30 no.4
• /
• pp.104-130
• /
• 2017

Objectives : This study was designed to signpost the study of brain, intelligence and memory, while interpreting the concept of 'Chongmyeong(聰明)' neotrically and linking it to the clinic of Korean medicine. Methods : In this paper, the meaning of the word 'Chongmyeong(聰明)' is divided into two parts, intelligence and memory. We also explored the relationship between brain science and 'Chongmyeong(聰明)' based on complex system theory, cognitive science and embodied cognition. Results : Through the process of refining the concept of 'Chongmyeong(聰明)' neoterically, we proposed the new method to understand the concept of 'Chongmyeong(聰明)'. Conclusions : The concept of 'Chongmyeong(聰明)' should be interpreted not as a reductionistic viewpoint of brain science but as a viewpoint of brain science based on visual and auditory system and complex system. Human cognition is physically embodied in the environment, from the viewpoint of embodied cognition that it is constituted and formed in an interactive context with society and culture connected with the environment.

• Journal of Korea Multimedia Society
• /
• v.19 no.9
• /
• pp.1647-1658
• /
• 2016

RGB+D database has been widely used in object recognition, object tracking, robot control, to name a few. While rapid advance of active depth sensing technologies allows for the widespread of indoor RGB+D databases, there are only few outdoor RGB+D databases largely due to an inherent limitation of active depth cameras. In this paper, we propose a novel method used to build outdoor RGB+D databases. Instead of using active depth cameras such as Kinect or LIDAR, we acquire a pair of stereo image using high-resolution stereo camera and then obtain a depth map by applying stereo matching algorithm. To deal with estimation errors that inevitably exist in the depth map obtained from stereo matching methods, we develop an approach that estimates confidence of depth maps based on unsupervised learning. Unlike existing confidence estimation approaches, we explicitly consider a spatial correlation that may exist in the confidence map. Specifically, we focus on refining confidence feature with the assumption that the confidence feature and resultant confidence map are smoothly-varying in spatial domain and are highly correlated to each other. Experimental result shows that the proposed method outperforms existing confidence measure based approaches in various benchmark dataset.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 2007.11a
• /
• pp.439-443
• /
• 2007

Nowadays, activity recognition becomes a hot topic in context-aware computing. In activity recognition, machine learning techniques have been widely applied to learn the activity models from labeled activity samples. Most of the existing work uses only one learning method for activity learning and is focused on how to effectively utilize the labeled samples by refining the learning method. However, not much attention has been paid to the use of multiple classifiers for boosting the learning performance. In this paper, we use two methods to generate multiple classifiers. In the first method, the basic learning algorithms for each classifier are the same, while the training data is different (ASTD). In the second method, the basic learning algorithms for each classifier are different, while the training data is the same (ADTS). Experimental results indicate that ADTS can effectively improve activity recognition performance, while ASTD cannot achieve any improvement of the performance. We believe that the classifiers in ADTS are more diverse than those in ASTD.

• Journal of the Korean Magnetic Resonance Society
• /
• v.26 no.1
• /
• pp.1-9
• /
• 2022

There are two distinct approaches to improving the quality of protein NMR structures during refinement: all-atom force fields and accumulated knowledge-assisted methods that include Rosetta. Mao et al. reported that, for 40 proteins, Rosetta increased the accuracies of their NMR-determined structures with respect to the X-ray crystal structures (Mao et al., J. Am. Chem. Soc. 136, 1893 (2014)). In this study, we calculated 32 structures of those studied by Mao et al. using all-atom force field and implicit solvent model, and we compared the results with those obtained from Rosetta. For a single protein, using only the experimental NOE-derived distances and backbone torsion angle restraints, 20 of the lowest energy structures were extracted as an ensemble from 100 generated structures. Restrained simulated annealing by molecular dynamics simulation searched conformational spaces with a total time step of 1-ns. The use of GPU-accelerated AMBER code allowed the calculations to be completed in hours using a single GPU computer-even for proteins larger than 20 kDa. Remarkably, statistical analyses indicated that the structures determined in this way showed overall higher accuracies to their X-ray structures compared to those refined by Rosetta (p-value < 0.01). Our data demonstrate the capability of sophisticated atomistic force fields in refining NMR structures, particularly when they are coupled with the latest GPU-based calculations. The straightforwardness of the protocol allows its use to be extended to all NMR structures.

• Membrane Journal
• /
• v.32 no.4
• /
• pp.227-234
• /
• 2022

Wastewater is released from leather, textile, paint, wood, or dye processing industries as well as petroleum refining industries. Wastewater from these industries contains water pollutant such as heavy metals and nitrogen compounds and has high chemical oxygen demand (COD). While there various filtering pollutants from wastewater for safe disposal, membrane-based technology is one of the most efficient methods for its high efficiency and low cost. Among various membranes, zeolite membranes gain spotlight for its cost-effectiveness and have undergone a lot of research. This review is focused on recent progress in zeolite membrane for wastewater treatment in following order: i) wastewater treatment, ii) microfiltration membrane, iii) hollow fiber membrane, and iv) ultrafiltration membrane.

• Current Optics and Photonics
• /
• v.7 no.5
• /
• pp.545-556
• /
• 2023

This paper introduces volume-sharing multi-aperture imaging (VMAI), a potential approach proposed for volume reduction in space-borne imagers, with the aim of achieving high-resolution ground spatial imagery using deep learning methods, with reduced volume compared to conventional approaches. As an intermediate step in the VMAI payload development, we present a phase-1 design targeting a 1-meter ground sampling distance (GSD) at 500 km altitude. Although its optical imaging capability does not surpass conventional approaches, it remains attractive for specific applications on small satellite platforms, particularly surveillance missions. The design integrates one wide-field and three narrow-field cameras with volume sharing and no optical interference. Capturing independent images from the four cameras, the payload emulates a large circular aperture to address diffraction and synthesizes high-resolution images using deep learning. Computational simulations validated the VMAI approach, while addressing challenges like lower signal-to-noise (SNR) values resulting from aperture segmentation. Future work will focus on further reducing the volume and refining SNR management.