• Journal of the Korean Institute of Intelligent Systems
• /
• v.21 no.5
• /
• pp.549-554
• /
• 2011

This paper presents the stabilization method for polynomial fuzzy large-scale system by using output feedback controller. Each sub system of the large-scale system is transformed into polynomial fuzzy model, and then output feedback controller is designed to stabilize the large-scale system. Stabilization condition is derived as sum-of-square (SOS) condition by applying the polynomial Lyapunov function. This condition can be easily solved by SOSTOOLS which is the third party of the MATLAB. From these solutions, output feedback controller gain can be obtained by SOS condition. Finally, a simulation example is presented to illustrate the effectiveness and the suitability of the proposed method.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.4C
• /
• pp.321-328
• /
• 2010

A Rayleigh fading channel simulator that realizes given correlation properties between two channels such as downlink/uplink is described. We propose an improved channel simulator that provides more accurate match between reference correlation and simulated one. The proposed channel simulator is based on a sum-of-sinusoids (SOS) method that handles finite sums of weighted sinusoid functions. SOS method is widely accepted in generating fading signals and obtain the exact match with the reference model if infinite number of weighted sinusoids are used. The proposed channel simulator minimizes mean-square-error (MSE) to obtain a close matched correlation properties.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.7
• /
• pp.1270-1276
• /
• 2016

This paper proposes the controller design for regulation control of two-link robot arm using sum of squares (SOS) control method that takes into account the input constraint. The existing studies of two link robotic arm system used a linear model of all the non-linearity of the system is linearized. For a linear controller, since the model of the system is simplified, it is possible to design a controller in consideration of constraints on the disturbance. However, there is a limit to the performance using a linearized model for a system with a complex nonlinear properties. To compensate for this in the case of using a fuzzy LMI method, it is necessary to have a large number of linear models and thus there is a disadvantage that the system becomes complicated. To solve these problems, we represents a two-link robot arm system with a polynomial model using a Taylor series expansion and design the controller considering the case where the magnitude of the control input is limited using SOS method. We demonstrate by simulations the feasibility of the proposed algorithm.

• Journal of Genetic Medicine
• /
• v.16 no.1
• /
• pp.1-9
• /
• 2019

Noonan syndrome (NS) and NS-related disorders (cardio-facio-cutaneous syndrome, Costello syndrome, NS with multiple lentigines, or LEOPARD [lentigines, ECG conduction abnormalities, ocular hypertelorism, pulmonic stenosis, abnormal genitalia, retardation of growth and sensory neural deafness] syndrome) are collectively named as RASopathies. Clinical presentations are similar, featured with typical facial features, short stature, intellectual disability, ectodermal abnormalities, congenital heart diseases, chest & skeletal deformity and delayed puberty. During past decades, molecular etiologies of RASopathies have been growingly discovered. The functional perturbations of the RAS-mitogen-activated protein kinase pathway are resulted from the mutation of more than 20 genes (PTPN11, SOS1, RAF1, SHOC2, BRAF, KRAS, NRAS, HRAS, MEK1, MEK2, CBL, SOS2, RIT, RRAS, RASA2, SPRY1, LZTR1, MAP3K8, MYST4, A2ML1, RRAS2). The PTPN11 (40-50%), SOS1 (10-20%), RAF1 (3-17%), and RIT1 (5-9%) mutations are common in NS patients. In this review, the constellation of overlapping clinical features of RASopathies will be described based on genotype as well as their differential diagnostic points and management.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.8
• /
• pp.2552-2570
• /
• 2022

Underwater images usually have various problems, such as the color cast of underwater images due to the attenuation of different lights in water, the darkness of image caused by the lack of light underwater, and the haze effect of underwater images because of the scattering of light. To address the above problems, the channel attention mechanism, strengthen-operate-subtract (SOS) boosting mechanism and gated fusion module are introduced in our paper, based on which, an underwater image recovery network is proposed. First, for the color cast problem of underwater images, the channel attention mechanism is incorporated in our model, which can well alleviate the color cast of underwater images. Second, as for the darkness of underwater images, the similarity between the target underwater image after dehazing and color correcting, and the image output by our model is used as the loss function, so as to increase the brightness of the underwater image. Finally, we employ the SOS boosting module to eliminate the haze effect of underwater images. Moreover, experiments were carried out to evaluate the performance of our model. The qualitative analysis results show that our method can be applied to effectively recover the underwater images, which outperformed most methods for comparison according to various criteria in the quantitative analysis.

• Steel and Composite Structures
• /
• v.51 no.4
• /
• pp.417-440
• /
• 2024

Artificial neural networks (ANN) have been the focus of several studies when it comes to evaluating the pile's bearing capacity. Nonetheless, the principal drawbacks of employing this method are the sluggish rate of convergence and the constraints of ANN in locating global minima. The current work aimed to build four ANN-based prediction models enhanced with methods from the black hole algorithm (BHA), league championship algorithm (LCA), shuffled complex evolution (SCE), and symbiotic organisms search (SOS) to estimate the carrying capacity of piles in cold climates. To provide the crucial dataset required to build the model, fifty-eight concrete pile experiments were conducted. The pile geometrical properties, internal friction angle 𝛗 shaft, internal friction angle 𝛗 tip, pile length, pile area, and vertical effective stress were established as the network inputs, and the BHA, LCA, SCE, and SOS-based ANN models were set up to provide the pile bearing capacity as the output. Following a sensitivity analysis to determine the optimal BHA, LCA, SCE, and SOS parameters and a train and test procedure to determine the optimal network architecture or the number of hidden nodes, the best prediction approach was selected. The outcomes show a good agreement between the measured bearing capabilities and the pile bearing capacities forecasted by SCE-MLP. The testing dataset's respective mean square error and coefficient of determination, which are 0.91846 and 391.1539, indicate that using the SCE-MLP approach as a practical, efficient, and highly reliable technique to forecast the pile's bearing capacity is advantageous.

• Journal of Korean Academy of Nursing
• /
• v.23 no.2
• /
• pp.299-315
• /
• 1993

Koreans are one of the fastest growing immigrant groups in America. Stress responses and stressors among this large cultural minority has been rarely been studied by nursing researchers. Adjusting to life in foreign country produces a great deal of stress. Differences in culture, language, expectations and social behavior can lead to misunderstandings between health care providers and clients. These misunderstandings are not well accounted for in health assessment. This study investigated the relationship between life events or / and daily activities as a stressor and the symptoms of stress among a sample of Korean immigrants in America. The symptoms of stress scale (SOS) was used to identify stress responses and open-ended questions were used to identify life events and daily activities considered by the respondents to be stressful. A simple random sample of 283 subjects was selected from the Directory of the Korean Society of Chicago, New York, Los Angeles, Philadelphia and Seattle. Demographically, the subjects ranged in age from 20 to 69 years, and the percentage of women and men was approximately 50% each. Almost ninety percent of the subjects were highly educated, 17% owners of business, 19% white collar professionals, 14% employed in sales or as skilled /unskilled labor, 27% as housewives and students and 3％ had no occupation. The total group SOS mean was 0.8042 ; the SOS men for man was 0.7371, and for women was 0.8713. The stress response of this subject group was high, -the stress response of women higher than that for men. In an earlier study(June, 1992) with another sample, the total mean SOS score was similar to this one. The main stressful life events or / and daily activities were, in order, economic problems (N=97), interpersonal problems (N=68), children care problems (N=258), health problems (N=49), communication problems (N=42), family problems (N=38), worry about future career (N=36), and religious problems (N=25). There was a significant difference in the SOS means between the group that expressed life events or / and daily activities to be stressful and the group that did not. Interpersonal relationships and economic and family problems were stressors for those who complained about peripheral manifestations. cardiopulmonary symptoms, central-neurological symptoms, gastrointestinal symptoms, muscle ten-sion, habitual patterns, depression, anxiety, emotional irritability and cognitive disorganization. In summary, interpersonal relationships and economic and family problems influenced stress response manifestations. Income, the number of people in the family, the year of immigration. the level of education, and marital status were related to physiological and psychosocial stress responses.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.10
• /
• pp.1746-1750
• /
• 2007

The second-order scattering (SOS) phenomenon of the interaction of Pd nanoparticles with protein was reported and a simple, sensitive, palladium nanoparticle-based assay for trace amount of protein with SOS technique was developed. The SOS intensities were significantly enhanced due to the interaction of Pd nanoparticles with bovine serum albumin (BSA) or human serum albumin (HSA) at pH 3.5 or 4.0, respectively. The maximum SOS peak appeared at 260/520 nm (λex/λem). The optimal experiment conditions, affecting factors and the influence of some coexisting substances were checked. The SOS intensity increased proportionally with the increase of Pd concentration below 3.0 × 10?5 mol·L?1, while declined gradually above 4.0 × 10?5 mol·L?1. BSA within the range of 0.01-2.6 μg·mL?1 and HSA of 0.01-1.7 μg·mL?1 can be detected with this method and the detection limits were 2.3 and 11.2 ng·mL?1, respectively. The method was successfully applied to the quantitative detection of total protein content in human serum samples with the maximum relative standard deviation (RSD) lower than 2.6% and the recoveries over the range of 99.5-100.5%.

• Korean Journal of Food Science and Technology
• /
• v.30 no.2
• /
• pp.439-445
• /
• 1998

The antimutagenic activity of the water extract of Rehmannia glutinosa Liboschitz (RG) on the mutagenicity induced by 4-nitroquinoline 1-oxide (4-NQO), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), mitomycin C (MMC), $aflatoxin\;B_1\;(AFB_1)$ and benzo(a)pyrene [B(a)P] were studied using the SOS Chromotest with Escherichia coli PQ37. The water extract of RG was separated into methanol soluble and methanol insoluble parts. The methanol soluble part exhibited higher inhibition effects than the methanol insoluble part against the mutagenic activities of five mutagens. Step-wise fractionation of methanol soluble part was done using methanol, ethyl acetate and water. Among these fractions, water fraction had the strongest inhibitory effects against the mutagenenicity of five model mutagens, showing $4.5{\sim}29.5%$ inhibition, but the $AFB_1$ mutagenic potency was increased slightly by ethyl acetate fraction. The water fraction was further partitioned by sephadex LH-20 column chromtography, and 9 subfractions were obtained. The fraction III showed the strongest inhibitory effects with dose response against the mutagenic activities induced by all the tested chemical mutagens. The inhibition rates of fraction III at concentration of $400\;{\mu}g/assay$ were 29%, 35%, 38%, 25% and 24% against 4-NQO, MNNG, MMC, AFBl and B(a)P, respectively. The fraction III also exhibited a strong bio-an-timutagenicity against 4-NQO and $AFB_1$ by showing more than 40% inhibition.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.10
• /
• pp.1430-1437
• /
• 2011

Synthesis conditions of cocoa butter equivalents were optimized using the response surface method (RSM) by interesterification of canola oil (Ca), palmitic ethyl ester (PEE), and stearic ethyl ester (StEE). The reaction was catalyzed by immobilized lipase (Lipozyme TLIM) from Thermomyces lanuginosa to produce structured lipids containing a composition of triacylglycerols similar to cocoa butter. Reaction conditions were optimized using D-optimal design with the three reaction factors of the substrate molar ratio of canola oil to palmitic ethyl ester and stearic ethyl ester (Ca : PEE : StEE=1:1:3, 1:1.66:5, 1:2:6, 1:2.33:7, 1:3:9, $X_1$), enzyme ratio (2~6%, $X_2$), and reaction time (30~270 min, $X_3$). The optimal conditions that minimized acyl-migration while maximizing 1-palmitoyl-2-oleoyl-3-stearoyl glycerol (POS), 1,3-distearoyl-2-oleoyl glycerol (SOS), and 1,3-dipalmitoyl-2-oleoyl glycerol (POP) were predicted, resulting in Ca : PEE : StEE=1:3:9, 6% of enzyme ratio, and 40 min of reaction time. The reaction product of structured lipids was synthesized again under the same conditions, showing 10.43 area% of acyl-migration, 25.31 area% of POS/PSO, 19.79 area% of SOS, and 11.22 area% of POP.