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1.
This paper proposes a technique for the detection of head nod and shake gestures based on eye tracking and head motion decision. The eye tracking step is divided into face detection and eye location. Here, we apply a motion segmentation algorithm that examines differences in moving people’s faces. This system utilizes a Hidden Markov Model-based head detection module that carries out complete detection in the input images, followed by the eye tracking module that refines the search based on a candidate list provided by the preprocessing module. The novelty of this paper is derived from differences in real-time input images, preprocessing to remove noises (morphological operators and so on), detecting edge lines and restoration, finding the face area, and cutting the head candidate. Moreover, we adopt a K-means algorithm for finding the head region. Real-time eye tracking extracts the location of eyes from the detected face region and is performed at close to a pair of eyes. After eye tracking, the coordinates of the detected eyes are transformed into a normalized vector of x-coordinate and y-coordinate. Head nod and shake detector uses three hidden Markov models (HMMs). HMM representation of the head detection can estimate the underlying HMM states from a sequence of face images. Head nod and shake can be detected by three HMMs that are adapted by a directional vector. The directional vector represents the direction of the head movement. The vector is HMMs for determining neutral as well as head nod and shake. These techniques are implemented on images, and notable success is notified. 相似文献
2.
Bi3Mo2Fe1P x oxide catalysts were prepared by a co-precipitation method and the influence of phosphorous content on the catalytic performance in the oxidative dehydrogenation of 1-butene was investigated. The addition of phosphorous up to 0.4mole ratio to Bi3Mo2Fe1 oxide catalyst led to an increase in the catalytic performance; however, a higher phosphorous content (above P=0.4) led to a decrease of conversion. Of the tested catalysts, Bi3Mo2Fe1P0.4 oxide catalyst exhibited the highest catalytic performance. Characterization results showed that the catalytic performance was related to the quantity of a π-allylic intermediate, facile desorption behavior of adsorbed intermediates and ability for re-oxidation of catalysts. 相似文献
3.
Myung-Sun Kim Kyunggon Kim Su Kyung Oh Gidae Lee Jin-Ock Kim Lan Li Jung-Hyun Park Kwang-Hyun Baek 《International journal of molecular sciences》2021,22(12)
To increase the half-life of growth hormones, we proposed its long-lasting regulation through the ubiquitin-proteasome system (UPS). We identified lysine residues (K67, K141, and K166) that are involved in the ubiquitination of human growth hormone (hGH) using ubiquitination site prediction programs to validate the ubiquitination sites, and then substituted these lysine residues with arginine residues. We identified the most effective substituent (K141R) to prevent ubiquitination and named it AUT-hGH. hGH was expressed and purified in the form of hGH-His, and ubiquitination was first verified at sites containing K141 in the blood stream. Through the study, we propose that AUT-hGH with an increased half-life could be used as a long-lasting hGH in the blood stream. 相似文献
4.
Yoon-Jung Moon Joseph Kwon Sung-Ho Yun Hye Li Lim Jonghyun Kim Soo Jung Kim Sung Gyun Kang Jung-Hyun Lee Seung Il Kim Young-Ho Chung 《International journal of molecular sciences》2015,16(5):9167-9195
The hyperthermophilic archaeon Thermococcus onnurineus NA1 has been shown to produce H2 when using CO, formate, or starch as a growth substrate. This strain can also utilize elemental sulfur as a terminal electron acceptor for heterotrophic growth. To gain insight into sulfur metabolism, the proteome of T. onnurineus NA1 cells grown under sulfur culture conditions was quantified and compared with those grown under H2-evolving substrate culture conditions. Using label-free nano-UPLC-MSE-based comparative proteomic analysis, approximately 38.4% of the total identified proteome (589 proteins) was found to be significantly up-regulated (≥1.5-fold) under sulfur culture conditions. Many of these proteins were functionally associated with carbon fixation, Fe–S cluster biogenesis, ATP synthesis, sulfur reduction, protein glycosylation, protein translocation, and formate oxidation. Based on the abundances of the identified proteins in this and other genomic studies, the pathways associated with reductive sulfur metabolism, H2-metabolism, and oxidative stress defense were proposed. The results also revealed markedly lower expression levels of enzymes involved in the sulfur assimilation pathway, as well as cysteine desulfurase, under sulfur culture condition. The present results provide the first global atlas of proteome changes triggered by sulfur, and may facilitate an understanding of how hyperthermophilic archaea adapt to sulfur-rich, extreme environments. 相似文献
5.
The effect of surface functional groups on chain interdiffusion at the interfacial zone of reactive latexes was investigated. A series of latexes with different surface functionalities was prepared by batch or shot-growth emulsion polymerizations. The particle surface properties were varied by changing the number density of functional groups. The rate of tensile strength development decreases with the increasing number density of surface functional groups, which indicated that inter-particle crosslinking restricted the interdiffusion of polymer chains during film formation and annealing. The average diffusion coefficient D of polymer chains across particle interfaces was obtained from dynamic mechanical analysis and compared well with the results from the rate of tensile strength development. The magnitude of D of the reactive latex film was lower than that of the homopolymer film. The lower chain mobility of reactive latexes prevented mechanical strength development. 相似文献
6.
Hee-Su KimShin Jung Park Sun-Hee HyunSeung-Ok Yang Jaehwi LeeJoong-Hyuck Auh Jung-Hyun KimSoo-Muk Cho Philip J. Marriott Hyung-Kyoon Choi 《Food research international (Ottawa, Ont.)》2011,44(7):1977-1987
Nuclear magnetic resonance (NMR) techniques coupled with multivariate data analysis were used to conduct monitoring of biochemical changes of black raspberry fruits at different stages of maturation and under various extraction and NMR dissolution solvent conditions: extraction with 50% methanol and D2O as an NMR dissolution solvent, extraction with 50% methanol and 50% methanol-d4 as an NMR dissolution solvent, and extraction with 100% ethyl acetate and 100% methanol-d4 as an NMR dissolution solvent. Partial least-squares discriminant analysis reliably distinguished black raspberry fruits according to the maturation stage, whereby the relative levels of various compounds such as amino acids, organic acids, sugars and phenolic compounds were compared using analysis of variance. Sucrose and most of the amino acids, and organic acids decreased, whereas fructose, glucose, and cyanidins increased in relative concentration according to maturation of black raspberry fruits. The total number and kinds of assigned compounds of the three solvent systems were also compared. This research demonstrates that the metabolic profile of black raspberry fruits changes during maturation, and provides objective criteria for determining the stage of black raspberry fruit maturation via a 1H NMR-based metabolomics technique using multiple solvent systems. 相似文献
7.
Jeong-Won Yoon Bo-In Noh Jung-Hyun Choi Seung-Boo Jung 《Journal of Materials Science: Materials in Electronics》2011,22(7):745-750
We investigated the effect of adding cerium (Ce) to low Ag content Sn–1.0wt.%Ag solder on the interfacial reactions between
the Sn–1.0Ag solder and Cu substrate. The formation and growth of interfacial intermetallic compounds (IMCs) between the Sn–1.0Ag–0.3Ce
solder and Cu substrate were studied and the results were compared to those obtained for the Ce-free Sn–1.0Ag/Cu and most
promising Sn–3.0Ag–0.5Cu/Cu systems. The addition of Ce to the Sn–Ag solder significantly reduced the growth of the interfacial
Cu–Sn IMCs, retarded the interfacial reactions between the solder and the substrate, and prevented the IMC from spalling from
the interface. The Sn–1.0Ag–0.3Ce solder alloy had a good interfacial stability with the Cu substrate during solid-state isothermal
aging in the viewpoint of IMC growth. 相似文献
8.
Min-Jae Yoon Jung-Hyun In Hyeon-Cheol Lee Chang-Ha Lee 《Korean Journal of Chemical Engineering》2006,23(5):842-846
Phosphor yttrium aluminum garnet (Y3Al5O12, YAG) doped with Eu (10 at%) was synthesized by supercritical water (SCW) and solid-state methods in a batch reactor. The
crystals, morphologies and luminescent properties of the phosphors obtained from different pH conditions in the SCW were studied.
Pure YAG phase was successfully synthesized at the alkaline condition in the SCW without formation of intermediate phases,
while the size and luminescent property of YAG: Eu were strongly affected by pH condition. The luminescent intensity of YAG:
Eu by the SCW method without further thermal treatment is stronger than that by the solid-state method with thermal treatment. 相似文献
9.
Mi-Young Kim Jung-Hyun Park Chae-Ho Shin Sang-Wook Han Gon Seo 《Catalysis Letters》2009,133(3-4):288-297
Platinum catalysts supported on silica, silica-alumina and alumina supports were prepared using four different cationic and anionic platinum precursors in order to examine the contribution of the precursors and supports to the platinum dispersion. The pH adjustment of the precursor suspension to obtain an opposing surface charge of the support to that on the platinum precursor ions considerably improved the platinum dispersion by strengthening their adsorption on the support. However, exceptional platinum dispersion was achieved, regardless of the precursor and support, by simultaneous pH adjustment and titania incorporation on the supports. The increase in the interaction between the platinum precursor and the titania-incorporated support raised the dispersion and stability of the platinum catalysts with high-loading, even after reduction at 400 °C. The physico-chemical states of platinum and titanium were investigated by XRD, TEM, XAFS spectroscopy and CO adsorption technique. The platinum catalysts supported on the titania-incorporated supports with pH adjustment exhibited highly dispersed platinum particles ranging in size from 1 to 3 nm. They also exhibited high catalytic activity in the oxidation of carbon monoxide because of its incorporated titania and partially oxidized, small platinum particles. 相似文献
10.
Core-shell composite particles were prepared by a heterocoagulation and annealing process, in which control of the number of chemical linkages in the interfacial zone without changing other properties was possible using five kinds of small size shell particles (SP) with different carboxyl charge density and one large size core particle (LP) with an epoxy functional group. These functional groups were capable of associating with one another through chemical reaction by thermal treatment. With increase of surface functionality of SP, the toughness was found to be higher. This indicated that a higher number of interfacial linkages between core and shell materials resulted in an increase in the critical stress intensity factor KIc of the modified poly(methyl methacrylate) (PMMA) composite. The interfacial properties between core and shell phase therefore play an important role in the impact behaviour of composite materials. ©1997 SCI 相似文献