• Title/Summary/Keyword: Vector optimization

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Analysis of Skin Color Pigments from Camera RGB Signal Using Skin Pigment Absorption Spectrum (피부색소 흡수 스펙트럼을 이용한 카메라 RGB 신호의 피부색 성분 분석)

  • Kim, Jeong Yeop
    • KIPS Transactions on Software and Data Engineering
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    • v.11 no.1
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    • pp.41-50
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    • 2022
  • In this paper, a method to directly calculate the major elements of skin color such as melanin and hemoglobin from the RGB signal of the camera is proposed. The main elements of skin color typically measure spectral reflectance using specific equipment, and reconfigure the values at some wavelengths of the measured light. The values calculated by this method include such things as melanin index and erythema index, and require special equipment such as a spectral reflectance measuring device or a multi-spectral camera. It is difficult to find a direct calculation method for such component elements from a general digital camera, and a method of indirectly calculating the concentration of melanin and hemoglobin using independent component analysis has been proposed. This method targets a region of a certain RGB image, extracts characteristic vectors of melanin and hemoglobin, and calculates the concentration in a manner similar to that of Principal Component Analysis. The disadvantage of this method is that it is difficult to directly calculate the pixel unit because a group of pixels in a certain area is used as an input, and since the extracted feature vector is implemented by an optimization method, it tends to be calculated with a different value each time it is executed. The final calculation is determined in the form of an image representing the components of melanin and hemoglobin by converting it back to the RGB coordinate system without using the feature vector itself. In order to improve the disadvantages of this method, the proposed method is to calculate the component values of melanin and hemoglobin in a feature space rather than an RGB coordinate system using a feature vector, and calculate the spectral reflectance corresponding to the skin color using a general digital camera. Methods and methods of calculating detailed components constituting skin pigments such as melanin, oxidized hemoglobin, deoxidized hemoglobin, and carotenoid using spectral reflectance. The proposed method does not require special equipment such as a spectral reflectance measuring device or a multi-spectral camera, and unlike the existing method, direct calculation of the pixel unit is possible, and the same characteristics can be obtained even in repeated execution. The standard diviation of density for melanin and hemoglobin of proposed method was 15% compared to conventional and therefore gives 6 times stable.

Establishment of a NanoBiT-Based Cytosolic Ca2+ Sensor by Optimizing Calmodulin-Binding Motif and Protein Expression Levels

  • Nguyen, Lan Phuong;Nguyen, Huong Thi;Yong, Hyo Jeong;Reyes-Alcaraz, Arfaxad;Lee, Yoo-Na;Park, Hee-Kyung;Na, Yun Hee;Lee, Cheol Soon;Ham, Byung-Joo;Seong, Jae Young;Hwang, Jong-Ik
    • Molecules and Cells
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    • v.43 no.11
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    • pp.909-920
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    • 2020
  • Cytosolic Ca2+ levels ([Ca2+]c) change dynamically in response to inducers, repressors, and physiological conditions, and aberrant [Ca2+]c concentration regulation is associated with cancer, heart failure, and diabetes. Therefore, [Ca2+]c is considered as a good indicator of physiological and pathological cellular responses, and is a crucial biomarker for drug discovery. A genetically encoded calcium indicator (GECI) was recently developed to measure [Ca2+]c in single cells and animal models. GECI have some advantages over chemically synthesized indicators, although they also have some drawbacks such as poor signal-to-noise ratio (SNR), low positive signal, delayed response, artifactual responses due to protein overexpression, and expensive detection equipment. Here, we developed an indicator based on interactions between Ca2+-loaded calmodulin and target proteins, and generated an innovative GECI sensor using split nano-luciferase (Nluc) fragments to detect changes in [Ca2+]c. Stimulation-dependent luciferase activities were optimized by combining large and small subunits of Nluc binary technology (NanoBiT, LgBiT:SmBiT) fusion proteins and regulating the receptor expression levels. We constructed the binary [Ca2+]c sensors using a multicistronic expression system in a single vector linked via the internal ribosome entry site (IRES), and examined the detection efficiencies. Promoter optimization studies indicated that promoter-dependent protein expression levels were crucial to optimize SNR and sensitivity. This novel [Ca2+]c assay has high SNR and sensitivity, is easy to use, suitable for high-throughput assays, and may be useful to detect [Ca2+]c in single cells and animal models.

Inverse Estimation of Geoacoustic Parameters in Shallow Water Using tight Bulb Sound Source (천해환경에서 전구음원을 이용한 지음향인자의 역추정)

  • 한주영;이성욱;나정열;김성일
    • The Journal of the Acoustical Society of Korea
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    • v.23 no.1
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    • pp.8-16
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    • 2004
  • An inversion method is presented for the determination of the compressional wave speed, compressional wave attenuation, thickness of the sediment layer and density as a function of depth for a horizontally stratified ocean bottom. An experiment for estimating those properties was conducted in the shallow water of South Sea in Korea. In the experiment, a light bulb implosion and the propagating sound were measured using a VLA (vertical line array). As a method for estimating the geoacoustic properties, a coherent broadband matched field processing combined with Genetic Algorithm was employed. When a time-dependent signal is very short, the Fourier transform results are not accurate, since the frequency components are not locatable in time and the windowed Fourier transform is limited by the length of the window. However, it is possible to do this using the wavelet transform a transform that yields a time-frequency representation of a signal. In this study, this transform is used to identify and extract the acoustic components from multipath time series. The inversion is formulated as an optimization problem which maximizes the cost function defined as a normalized correlation between the measured and modeled signals in the wavelet transform coefficient vector. The experiments and procedures for deploying the light bulbs and the coherent broadband inversion method are described, and the estimated geoacoustic profile in the vicinity of the VLA site is presented.

Production of Vanillin from Ferulic Acid Using Recombinant Strains of Escherichia coli

  • Yoon Sang-Hwal;Li Cui;Lee Young-Mi;Lee Sook-Hee;Kim Sung-Hee;Choi Myung-Suk;Seo Weon-Taek;Yang Jae-Kyung;Kim Jae-Yeon;Kim Seon-Won
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.4
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    • pp.378-384
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    • 2005
  • Vanillin is one of the world's principal flavoring compounds, and is used extensively in the food industry. The potential vanillin production of the bacteria was compared to select and clone genes which were appropriate for highly productive vanillin production by E. coli. The fcs (feruloyl-CoA synthetase) and ech (enoyl-CoA hydratase/aldolase) genes cloned from Amycolatopsis sp. strain HR104 and Delftia acidovorans were introduced to pBAD24 vector with $P_{BAD}$ promoter and were named pDAHEF and pDDAEF, respectively. We observed 160 mg/L vanillin production with E. coli harboring pDAHEF, whereas 10 mg/L of vanillin was observed with pDAHEF. Vanillin production was optimized with E. coli harboring pDAHEF. Induction of the fcs and ech genes from pDAHEF was optimized with the addition of 13.3 mM arabinose at 18 h of culture, from which 450 mg/L of vanillin was produced. The feeding time and concentration of ferulic acid were also optimized by the supplementation of $0.2\%$ ferulic acid at 18 h of culture, from which 500 mg/L of vanillin was obtained. Under the above optimized condition of arabinose induction and ferulic acid supplementation, vanillin production was carried out with four different types of media, M9, LB, 2YT, and TB. The highest vanillin production, 580 mg/L, was obtained with LB medium, a 3.6 fold increase in comparison to the 160 mg/L obtained before the optimization of vanillin production.

A Fast Inter-layer Mode Decision Method inScalable Video Coding (공간적 스케일러블 비디오 부호화에서 계층간 모드 고속 결정 방법)

  • Lee, Bum-Shik;Hahm, Sang-Jin;Park, Chang-Seob;Park, Keun-Soo;Kim, Mun-Churl
    • Journal of Broadcast Engineering
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    • v.12 no.4
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    • pp.360-372
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    • 2007
  • We propose a fast inter-layer mode decision method by utilizing coding information of base layer upward its enhancement layer inscalable video coding (SVC), also called MPEG-4 part 10 Advanced Video Coding Amendment 3 or H.264 Scalable Extension (SE) which is being standardized. In this paper, when the motion vectors from the base layer have zero motion (0, 0) in inter-layer motion prediction or the Integer Transform coefficients of the residual between current MB and the motion compensated MB by the predicted motion vectors from the base layer are all zero, the block mode of the corresponding block to be encoded at the enhancement layer is determined to be the $16{\times}16$ mode. In addition, if the predicted mode of the MB to be encoded at the enhancement layer is not equal to the $16{\times}16$ mode, then the rate-distortion optimization is only performed on the reduced candidated modes which are same or smaller partitioned modes. Our proposed method exhibits the complexity reduction in encoding time up to 72%. Nevertheless, it shows negligible PSNR degradation and bit rate increase up to 0.25dB and 1.73%, respectively.

Overproduction of Bacterial Trypsin in Streptomyces - Optimization for Streptomyces griseus Trypsin Production by Recombinant Streptomyces (미생물을 이용한 트립신 과대 생산 연구 - Streptomyces용 숙주-벡터계를 이용한 트립신 유전자의 대량발현 최적화 -)

  • Kim, Jong-Hee;Hong, Soon-Kwang
    • Microbiology and Biotechnology Letters
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    • v.36 no.1
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    • pp.28-33
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    • 2008
  • The expression vector (pWHM3-TR1R2) for sprT gene encoding Streptomyces griseus trypsin (SGT) followed by two regulatory genes, sgtR1 and sgtR2, was introduced into Streptomyces lividans TK24 and Streptomyces griseus IFO 13350. Various media with different compositions were used to maximize the productivity of SGT in the recombinant trains. he SGT productivity was best when the transformant of S. lividans TK24 was cultivated in R2YE medium (0.74 unit/mL) at 5 days of cultivation. C5/L (0.66 unit/mL) medium also gave a good productivity, but Livid (0.08 unit/mL) and NDSK (0.06 unit/mL) yielded poor productivities. S. griseus IFO 13350/pWHM3-TR1R2 produced SGT by 1.518 unit/mL (C5/L), 1.284unit/mL (R2YE),0.932 unit/mL (NDSK), and 0.295 unit/mL (Livid) at 7 days of cultivation, which was much higher than those from S. lividans TK24/TR1R2. The SGT protein was purified from the culture broth of S. griseus IFO 13350/pWHM3-TR1R2 in C5/L to homogeneity via ammonium sulfate fractionation, and CM-sepharose and SP-sepharose column chromatographies. The specific activity of purified SGT was 69,252 unit/mg, and the final purification fold and recovery yield were 6.5 and 1.4%, respectively.

Characteristic Analysis of Permanent Magnet Linear Generator by using Space Harmonic Method (공간고조파법을 이용한 영구자석 선형 발전기의 특성 해석)

  • Seo, Seong-Won;Choi, Jang-Young;Kim, Il-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.688-695
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    • 2017
  • This paper deals with characteristics analysis of a permanent magnet (PM) linear generator using analytical methods for wave energy harvesting. The wave energy is carried out from the movement of a yo-yo system. A linear generator using permanent magnets to generate a magnetic force itself does not require a separate power supply and has the advantage of simple maintenance. In addition to the use of a rare earth, a permanent magnet having a high-energy density can be miniaturized and lightweight, and can obtain high energy-conversion efficiency. We derived magnetic field solutions produced by the permanent magnet and armature reaction based on 2D polar coordinates and magnetic vector potential. Induced voltage is obtained via arbitrary sinusoidal input. In addition, electrical parameters are obtained, such as back-EMF constant, resistance, and self- and mutual-winding inductances. The space harmonic method used in this paper is confirmed by comparing it with finite element method (FEM) results. These facilitate the characterization of the PM-type linear generator and provide a basis for comparative studies, design optimization, and machine dynamic modeling.

Analysis of MPEG-4 Encoder for Object-based Video (실시간 객체기반 비디오 서비스를 위한 MPEG-4 Encoder 분석)

  • Kim Min Hoon;Jang Euee Seon;Lee Sun young;Moon Seok ju
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.1
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    • pp.13-20
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    • 2004
  • In this paper, we have analyzed the current MPEG-4 video encoding tools and proposed efcient coding techniques that reduce the complexity of the encoder. Until recently, encoder optimization without shape coding has been a major concern in video for wire/wireless low bit rate coding services. Recently, we found out that the computational complexity of MPEG-4 shape coding plays a very important role in the object-based coding through experiments. We have made an experiment whether we could get optimized object-based coding method through successfully combining latest optimized texture coding techniques with our proposed optimized shape coding techniques. In texture coding, we applied the MVFAST method for motion estimation. We chose not to use IVOPF(Intelligent VOP Formation) but to use TRB(Tightest Rectangular Boundary) for positioning VOP and, finally, to eliminate the spiral search of shape motion estimation to reduce the complexity in shape coding. As a result of experiment, our proposed scheme achieved improved time complexity over the existing reference software by $57.3\%$ and over the optimized method on which only shape coding was applied by $48.7\%$, respectively.

A Method to Find Feature Set for Detecting Various Denial Service Attacks in Power Grid (전력망에서의 다양한 서비스 거부 공격 탐지 위한 특징 선택 방법)

  • Lee, DongHwi;Kim, Young-Dae;Park, Woo-Bin;Kim, Joon-Seok;Kang, Seung-Ho
    • KEPCO Journal on Electric Power and Energy
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    • v.2 no.2
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    • pp.311-316
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    • 2016
  • Network intrusion detection system based on machine learning method such as artificial neural network is quite dependent on the selected features in terms of accuracy and efficiency. Nevertheless, choosing the optimal combination of features, which guarantees accuracy and efficienty, from generally used many features to detect network intrusion requires extensive computing resources. In this paper, we deal with a optimal feature selection problem to determine 6 denial service attacks and normal usage provided by NSL-KDD data. We propose a optimal feature selection algorithm. Proposed algorithm is based on the multi-start local search algorithm, one of representative meta-heuristic algorithm for solving optimization problem. In order to evaluate the performance of our proposed algorithm, comparison with a case of all 41 features used against NSL-KDD data is conducted. In addtion, comparisons between 3 well-known machine learning methods (multi-layer perceptron., Bayes classifier, and Support vector machine) are performed to find a machine learning method which shows the best performance combined with the proposed feature selection method.

Evaluation of Optimal Condition for Recombinant Bacterial Ghost Vaccine Production with Four Different Antigens of Streptococcus iniae-enolase, GAPDH, sagA, piaA (연쇄구균증 항원-enolase, GAPDH, sagA, piaA에 대한 재조합 고스트 박테리아 백신의 생산 최적화)

  • Ra, Chae-Hun;Kim, Yeong-Jin;Son, Chang-Woo;Jung, Dae-Young;Kim, Sung-Koo
    • Journal of Life Science
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    • v.19 no.7
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    • pp.845-851
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    • 2009
  • A vector harboring double cassettes; a heterologous gene expression cassette of pHCE-InaN-antigen and a ghost formation cassette of pAPR-cI-E lysis 37 SDM was constructed and introduced to E. coli DH5a. For the production of a bacterial ghost vaccine, bacterial ghosts from E. coli / Streptococcus iniae with four different types of antigens - enolase, GAPDH, sagA and piaA - were produced by the optimization of fermentation parameters such as a glucose concentration of 1 g/l, agitation of 300 rpm and aeration of 1 vvm. Efficiency of ghost bacteria formation was evaluated with cultures of OD$_{600}$=1.0, 2.0 and 3.0. The efficiency of the ghost bacteria formation was 99.54, 99.67, 99.99 and 99.99% with inductions at OD$_{600}$=3.0, 1.0, 2.0 and 1.0 for E. coli/S. iniae antigens enolase, piaA, GAPDH and sagA, respectively. Ghost bacteria as a vaccine was harvested by centrifugation. The antigen protein expressions were analyzed by SDS-PAGE and western blot analysis, and the molecular weights of the enolase, piaA, GAPDH and sagA were 78, 26, 67 and 26 kDa, respectively. The molecular weights of the expressed antigens were consistent with theoretical sizes obtained from the amino acid sequences.