• The Journal of the Acoustical Society of Korea
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• v.42 no.3
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• pp.203-213
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• 2023

In medical ultrasound imaging systems, Side lobes may appear if signals outside the imaging point are not completely removed during receive focusing. If the time signal of the side lobe overlaps with the time signal (main lobe) from the image point, it is difficult to completely remove it using filter processing in the time domain. However, In the receive focusing process, when time-channel signals are Fourier-transformed, the main lobe and side lobe signals are spatially separated in the spectral domain. Therefore, the side lobes can be suppressed by multiplying the image with magnitude weights, which are determined by the magnitudes of the main and side lobes calculated in the spectral domain. In addition, when the main lobe and the side lobe spectrum are adjacent, the distance weight was applied based on the distance between them. In a 5 MHz ultrasound imaging system using a 64-channel linear transducer, point reflector and speckle images with cysts of various brightness were synthesized and weights were applied to the ultrasound image. Using computer simulations, we confirmed that the side lobes were greatly reduced without affecting the spatial resolution in the point reflector image, and the contrast was significantly improved in the cyst image with computer simulations.

• Smart Structures and Systems
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• v.14 no.3
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• pp.327-345
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• 2014

This paper presents a composite control strategy for the active suppression of vibration due to the unknown disturbances, such as external excitation, harmonic effects and control spillover, as well as high-frequency accelerometer measurement noise in the all-clamped stiffened plate. The proposed composite control action based on the modal approach, consists of two contributions including feedback part and feedforward part. The feedback part is the well-known PID controller, which is widely used to increase the structure damping and improve its dynamic performance close to the resonance frequencies. In order to get better performance for vibration suppression, the weight matrixes is optimized by chaos sequence. Then an improved disturbance observer (IDOB) as the feedforward compensation part is developed to enhance the vibration suppression performance of PID under various disturbances and uncertainties. The proposed IDOB can simultaneously estimate the various disturbances dynamically as well as measurement noise acting on the system and suppress them by feedforward compensation design. A rigorous analysis is also given to show why the IDOB can effectively suppress the unknown disturbances and measurement noise. In order to verify the proposed composite control algorithm (IDOB-PID), the dSPACE real-time simulation platform is used and an experimental platform for the all-clamped stiffened plate active vibration control system is set up. The experimental results demonstrate the effectiveness, practicality and strong anti-disturbances ability of the proposed control strategy.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.3
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• pp.1-10
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• 2010

Objective : Erysipelas is an acute inflammation caused by pyogenic bacteria. This mainly involves the upper part of dermis. It begins as erythematous patches with tenderness, followed by fever, headache, chills and fatigue etc. It may results in edema, obstruction of lymphatics and sepsis. So this experiment is carried out for test whether the Bojeasodok-um subtracted Scrophulariae Radix, Lasiosphaera seu Calvatia, Isatidis Radix added indigo Naturalis, Lithospermi Radix have an anti-inflammatory effect and have suppression effect on immunocyte in the state of inflammation which induced by Erysipelas. Method : Experimental animals made use of 4-5 week-age(weight 20-25g) ICR(male) mouse. In the breeding farm, the lighting time was controlled from 7:00 am till 7:00 pm, the temperature was controlled So we concluded that BS is prospected as an anti-inflammatory agent to cure inflammation induced bywithin 18-23$23^{\circ}C$ and water and food were not limited.The freezing lyophilization powder which were extracted from Bojesodok-Um divided low dose group(200mg/kg-BSL) and high dose group(500mg/kg-BSH) and after melting in water, it was orally administered to the mouse. Compared with inflammation induced group which were induced by triggering-inflammation reagent Carageenan and Zymosan and normal contrast group, we measured the edema decrement effect,macrophage and spleen cell activation. Result : 1. BS has suppress inflammatory reaction induced by Carageenan. 2. BS has suppress increasing activation of abdominal cavity macrophage in the Carageenan and Zymosan induced inflammation. 3. BS has suppress increasing activation of spleen cell in the Carageenan and Zymosan induced inflammation. Based on the above result, BS was improved its suppression effect to the inflammatory reaction through the suppression of spleen cell and macrophage activation. So we concluded that BS is prospected as an anti-inflammatory agent to cure inflammation induced by Erysipelas.

• Journal of the Korean Society of Safety
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• v.32 no.2
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• pp.117-123
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• 2017

This study was intended to find methods of fire extinguishing system designs that can improve the equipment's usability. In this study, the fire suppression experiment through fire extinguishers and the data drawn through the experiment were analyzed, and then the guideline for the improvement of designs was presented. The procedure is as follows. A fire suppression experiment with the use of fire extinguishers was done by 43 average adults. The whole process of the fire suppression was videotaped, and then captured major scenes were analyzed with the use of RULA, a human engineering measurement tool. The analyzed data were divided into 4 steps, and then the guideline for design improvement was presented. The summary of the study is as follows. Step 1, Fire extinguisher distance step. To reduce overload occurring at the process of holding fire extinguishers suddenly, wheels are attached to the body of extinguishers, or pedestals are installed. Step 2, Fire extinguisher transportation step. The length of hose is extended, or fire fighting water is sprayed far, so that overload of legs occurring at the process of travel can be reduced. In addition, the weight of fire extinguisher shouldn't be over 2 kg. Step 3, Safety pin removal stage. Safety pins should be applied with button type, so that excessive posture of lower limbs and excessive twisting of wrists won't happen during safety pin removal process. Besides, safety pins should be designed for easy identification and operation. Step 4, Fire extinguishing agent spraying step. To reduce overload occurring at sudden spraying of fire fighting water, pressure should be increased gradually until high pressure. With the above study results applied to existing fire extinguisher design, it may contribute to reducing any fire damage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.233-239
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• 1999

This study was performed to evaluate the effects of the supplementation of lactic acid bacterias (LAB; S. thermophilus, L. acidophilus) aluminum accumulation and function kidney in rats treated with 250 g/g aluminum sulfate for 4 weeks. Fifty male Sprague Dawley strains were divided into five groups according to the types of supplement. the control, S. thermophilus culture group(A), autoclaved S. thermophilus culture(B), L. acidophilus culture group(C) and autoclaved L. acidophilus(D). The weight gain was increased by supplementation of S. thermophilus culture(A), autoclaved S. thermophilus culture(B), L. acidophilus culture(C), autoclaved L. acidophilus culture(D), especially by supplementation of S. thermophilus cultured(A) as compared to control group. The amount of water intake was increased in control group as compared to the LAB supplemented group. The content of aluminum were decreased 19.57%, 31.25%, 37.10%, and 32.40% in kidney after supplementation of non autoclaved culture group (A,C), and autoclaved group(B,D) respectively, as compared to control group. Water balance, urine volume, and excretion of sodium and potassium decreased in LAB supplemented group and control group. Excretion of creatinine increased in control group and tendency to increased in LAB supplemented group. In conclusion, the effect of suppression of aluminum accumulation was more effective in sup plementation of S. thermophilus culture(A), and L. acidophilus culture(C) than autoclaved S. thermo philus culture(B), and L. acidophilus culture(D).

• The Korea Journal of Herbology
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• v.22 no.4
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• pp.127-135
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• 2007

Objectives : In this study we investigated the antiobese effects of mixed pills of pickled black soybeans with herbs(herbal Chokong pill, hereafter HCKP) in rats fed high-fat diet. It was evaluated by measuring the changes of body weight, adipose tissues weight and lipid profiles in serum. Methods : Black soybeans were pickled in vinegar for 15 days to prepare Chokong, at room temperature. For treatment group, HCKP was prepared, which five kinds of medicinal herbs(Rhynchosia nulubilis, Glycyrrhiza uralensis, Zizyphus vulgaris, Atractylodes macrocephala K, Astragalus membranaceus and Cornus officinalis) were added to dried Chokong. Four groups of male Sprague-Dawley rats were fed different diets during 9 weeks: normal diet containing 5%(w/w) com oil, high-fat diet containing 10%(w/w) lard plus 5%(w/w) corn oil (HF), high-fat diet supplemented with 1%(T1) and 5%(T5) HCKP powder, respectively. Results : The T5 group had markedly lower body weight gain and weights of epididymal adipose tissue when compared with HF group. There were significant differences in visceral adipose tissue weights, serum total cholesterol and triglyceride concentrations between the HF and T5 group. Then, the efficacy of powered HCKP on body weight and lipid profiles change in rats fed high-fat diet were induced dose dependantly. Conclusion : These results suggest that the possibility of HCKP, as an antiobese functional formula, by suppression of body weight gain and improved lipid profiles.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.3
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• pp.662-672
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• 2009

Obesity has increased dramatically increased in recent days. It has resulted in obesity-associated diseases and metabolic syndromes including hyperlipidemia, diabetes and cardiovascular diseases. Our study was investigated to determine the antiobese effects of mixed 2 medicinal herbs (AR+AC) in rats fed high-fat diet with an abundance of carbohydrates. Two groups of male Sprague-Dawley rats were fed different diets during 8 weeks: normal diet containing 5% corn oil (w/w), high-fat diet containing 10% (w/w) lard plus 5% (w/w) corn oil (HF). And High-fat diet group was treated with saline or 100 mg/kg ARAC or 300 mg/kg ARAC (PO). Antiobese effect was evaluated by measuring the changes of body weight, adipose tissues weight. Also we examined levels of leptin, adiponectin and lipid profiles in serum. Finally we compared morphological change in adipocytes and hepatocytes between HF and ARAC group. Mixed combination of 2 medicinal herbs, but not alone, caused significant decrease in body weight, organ weight (liver, epididymal fat, and BAT) compared with control HF group. The ARAC group had markedly lower serum levels of adiponectin when compared with HF group. Also the epididymal white adipocyte size of ARAC group were diminished comparing to the HF group. These results suggest that the possibility of ARAC combination, as an antiobese formula, by suppression of body weight gain and increased lipid profiles.

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.1-8
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• 2015

This paper presents a Electrocardiogram(ECG) identification method using adaptive weight based on Least Mean Square Error(LMSE) optimization. With a preprocessing for noise suppression, we extracts the average ECG signal and its standard deviation at every time instant. Then the extracted information is stored in database. ECG identification is achieved by matching an input ECG signal with the information in database. In computing the matching scores, the standard deviation is used. The scores are computed by applying adaptive weights to the values of the input signal over all time instants. The adaptive weight consists of two terms. The first term is the inverse of the standard deviation of an input signal. The second term is the proportional one to the standard deviation between user SAECGs stored in the DB. Experimental results show up to 100% recognition rate for 32 registered people.

• Journal of Mechanical Science and Technology
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• v.16 no.1
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• pp.75-82
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• 2002

A simultaneous optimal design problem of structural and control systems is discussed by taking a 3-D truss structure as an object. We use descriptor forms for a controlled object and a generalized plant because the structural parameters appear naturally in these forms. We consider a minimum weight design problem for structural system and disturbance suppression problem for the control system. The structural objective function is the structural weight and the control objective function is $H_{\infty}$ norm from the disturbance input to the controlled output in the closed-loop system. The design variables are cross sectional areas of the truss members. The conditions for the existence of controller are expressed in terms of linear matrix inequalities (LMI) By minimizing the linear sum of the normalized structural objective function and control objective function, it is possible to make optimal design by which the balance of the structural weight and the control performance is taken. We showed in this paper the validity of simultaneous optimal design of structural and control systems.

• Korean Journal of Veterinary Research
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• v.37 no.2
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• pp.425-438
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• 1997

To assess the testicular toxicity induced by DA-125, a new anthracycline anticancer agent, the test substance was intraveneously administered to male beagle dogs at dose levels of 0, 0.0023, 0.0375, 0.15, and 0.6 mg/kg/day, 6 days a week for 26 weeks. At 0.6 mg/kg/day, 1 out of 3 dogs had died on day 42 of treatment and the other dogs were sacrificed on days 46 and 122 of treatment due to the increasingly severe clinical condition. Clinical signs considered to be related to treatment were included anorexia, vomiting, salivation, decreased activity, mucous and/or dark faeces, diarrhea, and swelling, abscess and/or ulceration of injection sites. Suppression in body weight gain, reduction in food intake, decreases in testicular weight and size, and hemorrhage of epididymis were also observed in male dogs. Microscopically, severe degenerative changes such as atrophy of seminiferous tubules, loss of germ cells, degeneration of germ cells, vacuolization of Sertoli cells, and hyperplasia of Leydig cells were observed in all dogs. Azoospermia in epididymal tubules, atrophy of epithelia in the cauda epididymis, and prostate atrophy were also found. At 0.15 mg/kg/day, anorexia, vomiting, salivation, diarrhea, and swelling of injection sites were observed. In addition, suppression in body weight gain and decreases in testicular weight and size were found in male dogs. Atrophy of seminiferous tubules, decrease of germ cells, degeneration, exfoliation and retention of germ cells, vacuolization of Sertoli cells, and hyperplasia of Leydig cells were observed by histopathological examination. Azoospermia in epididymal tubules and prostate atrophy were also found. At 0.0375 mg/kg/day, there were no clinical signs considered to be indicative of a reaction to treatment, but testicular size was significantly reduced. Microscopically, decreases in the number of spermatogonia and epidydimal speramtozoa were found. There were no evidences of general or testicular toxicity at 0.0023 mg/kg/day. These results indicate that DA-125 produces significant and persistent damage to the spermatogenic compartments of the testes in male beagle dogs.