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Medical Image Compression Using JPEG International Standard (JPEG 표준안을 이용한 의료 영상 압축)

  • Ahn, Chang-Beom;Han, Sang-Woo;Kim, Il-Yoen
    • Proceedings of the KIEE Conference
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    • 1993.07a
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    • pp.504-506
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    • 1993
  • The Joint Photographic Experts Group (JPEG) standard was proposed by the International Standardization Organization (ISO/SC 29/WG 10) and the CCITT SG VIII as an international standard for digital continuous-tone still image compression. The JPEG standard has been widely accepted in electronic imaging, computer graphics, and multi-media applications, however, due to the lossy character of the JPEG compression its application in the field of medical imaging has been limited. In this paper, the JPEG standard was applied to a series of head sections of magnetic resonance (MR) images (256 gray levels, $256{\times}256$ size) and its performance was investigated. For this purpose, DCT-based sequential mode of the JPEG standard was implemented using the CL550 compression chip and progressive and lossless coding was implemented by software without additional hardware. From the experiment, it appears that the compression ratio of about 10 to 20 was obtained for the MR images without noticeable distortion. It is also noted that the error signal between the reconstructed image by the JPEG and the original image was nearly random noise without causing any special-pattern-related artifact. Although the coding efficiency of the progressive and hierarchical coding is identical to that of the sequential coding in compression ratio and SNR, it has useful features In fast search of patient Image from huge image data base and in remote diagnosis through slow public communication channel.

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Ancient Dujiangyan Irrigation System and Geographical Conditions in the Western Part of Sichuan Basin in China (중국(中國) 사천분지(四川盆地) 서부(西部)의 고대(古代) 관개시설(灌漑施設)과 지역적(地域的) 여건(與件) - 도강언(都江堰)의 경우 -)

  • Lee, Joon-Sun
    • Journal of the Korean association of regional geographers
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    • v.8 no.1
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    • pp.65-82
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    • 2002
  • This study tries to examine the characteristics of the ancient Dujiangyan Irrigation System and geographical conditions in the western part of Sichuan Basin in China. The Dujiangyan System constructed in the third century B.C is located at the mouth of gorge of the River Mi. This spot shows that its altitude above sea level is higher than that of the three other rivers in this district. Also, this river reaches the maximum discharge. These facts reveal the spot has the great potentiality as an ideal location for man-made channels. Li Bing realized the "three magical projects": Yuzui and Jinggang Dyke(a water dividing dyke), Baopingkou(a water inlet), and Feishayan(a spillway). The dyke divided the River Min into two parts. The inner river is connected to the Baopingkou. And the Feishayan discharges flood and silt from the inner river to the outer. These projects have composed a scientific irrigation and drainage network. Finally, in the Chengdu Plain were digged a dozen channels for irrigation. Some of them are connected eastward to the River Bu. Since then the Dujiangyan System has been bring great benefits to agricultural production. This resulted in the population increase and establishment of new counties which have made the plain a "Land of Abundance".

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A Case Study on Seismic Refraction Tomography Survey for Subsurface Structure Interpretation (지하구조 해석을 위한 탄성파 굴절법 토모그라피 탐사 사례연구)

  • 유영준;유인걸;송무영
    • The Journal of Engineering Geology
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    • v.11 no.2
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    • pp.163-174
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    • 2001
  • For quantitative evaluation of geotechnical engineering properties such as rippability and diggability, clear interpretation on the subsUJiace velocity structures should be preceded by figuring out top soil, weathered and soft rock layers, shape of basement, fracture zones, geologic boundary and etC. from the seismic refraction data. It is very important to set up suitable field parameters, which are the configuration of profile and its length, spacings of geophones and sources and topographic conditions, for increasing field data Quality. Geophone spacing of 3 to 5m is reconunended in the land slope area of house land development site. In refraction tomography technique, the number of source points should be more than a Cluarter of available channel number of instrument and the subsurface structure interpretation can be decreased the artifact of inversion by topographic effect. Compared with core logging data, it is shown that the velocity range of the soil is less than 700m/s, weathered rock 700~1,200m/s, soft rock 1,200~1,800m/s on the velocity tomogram section. And the upper limit of P-wave velocity for rippability is estimated 1,200 to 1,800m/s in land slope area of gneiss.

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Experimental Study of Collapse Delay Effect of Riprap on Dam Slope (사력댐 사석 보호공의 붕괴 지연 효과에 대한 실험 연구)

  • Jeong, Seokil;Kim, Seung Wook;Kim, Hong Taek;Lee, Seung Oh
    • Journal of Korean Society of Disaster and Security
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    • v.11 no.1
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    • pp.31-38
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    • 2018
  • The 99.1% of small dam and most of the levees in Korea are soil dam which can be constructed with lower cost and less effort compared with ones made of concrete. However, they are so vulnerable to overflow. Sudden collapses of these strucrues lead to increase flow rate rapidly, which may cause catastrophic problems in downstream regions. In this study, the experimental study on the collapse delay effect of riprap that was laid on slope of soil levee was carried out. A prismatic rectangular open channel was used and three different sizes of the riprap were installed on slope of a scaled earth dam. A new formula for the collapse time of the levee with the installation of riprap was presented, using the previous researches and the dimensional analysis. In this process, an unsteady flow condition was considered to derive the deviation time of the riprap. And additional experiments were conducted to understand the effect of reinforcement of riprap, and it was found that the reinforcement of riprap was more effective than twice sizing of intial riprap. If the collapse time is delayed, EAP (Emergency Action Plan) and forecasting can greatly reduce the degree of flood damage. Also, it will be meaningful that the results of this study are used for river design.

Involvement of Bcl-2 Family and Caspases Cascade in Sodium Fluoride-Induced Apoptosis of Human Gingival Fibroblasts

  • Jung, Ji-Yeon;Park, Jae-Hong;Jeong, Yeon-Jin;Yang, Kyu-Ho;Choi, Nam-Ki;Kim, Sun-Hun;Kim, Won-Jae
    • The Korean Journal of Physiology and Pharmacology
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    • v.10 no.5
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    • pp.289-295
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    • 2006
  • Sodium fluoride (NaF) has been shown to be cytotoxic and elicit inflammatory response in human. However, the cellular mechanisms underlying NaF-induced cytotoxicity in periodontal tissues have not yet been elucidated. This study is aimed to investigate the mechanisms of NaF-induced apoptosis in human gingival fibroblast (HGF). NaF decreased the cell viability of HGF in a dose- and time-dependent manner. NaF gave rise to apoptotic morphological changes including cell shrinkage, chromatin condensation, and DNA fragmentation. However, NaF did not affect the production of ROS. In addition, NaF augumented cytochrome c release from mitochondria into the cytosol, and enhanced caspase -9 and -3 activities., cleavage (85 kDa fragments) of poly (ADP-ribose) polymerase (PARP) and upregulation of voltage-dependent anion channel (VDAC) 1. These results demonstrated that NaF-induced apoptosis in HGF may be mediated with mitochondria. Furthermore, NaF elevated caspase-8 activity and upregulated Fas-ligand (Fas-L), suggesting involvement of death receptor mediated pathway in NaF-induced apoptosis. Expression of Bcl-2, an anti-apoptotic Bcl-2 family, was downregulated, whereas expression of Bax, a pro-apoptotic Bcl-2 family, was not affected in NaF-treated HGF. These results suggest that NaF induces apoptosis in HGF through both mitochondria- and death receptor-mediated pathway mediated by Bcl-2 family.

DAMGO, a ${\mu}-Opioid$ Agonist and Cholecystokinin-Octapeptide Have Dual Modulatory Effects on Capsaicin-Activated Current in Rat Dorsal Root Ganglion Neurons

  • Eun, Su-Yong;Kim, Ji-Mok;Lee, Ji-Hye;Jung, Sung-Jun;Park, Joo-Min;Park, Yun-Kyung;Kim, Dong-Kwan;Kim, Sang-Jeong;Kwak, Ji-Yeon;Kim, Jun
    • The Korean Journal of Physiology and Pharmacology
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    • v.5 no.1
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    • pp.71-78
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    • 2001
  • Capsaicin, a pungent ingredient of hot pepper, elicits an intense burning pain when applied cutaneously and intradermally. Activation of capsaicin-gated channel in C-type dorsal root ganglion (DRG) neurons produces nonselective cationic currents. Although electrophysiological and biochemical properties of capsaicin-activated current $(I_{CAP})$ were studied, the regulatory mechanism and intracellular signaling pathway are still unclear. In the present study, we investigated the modulations of $I_{CAP}$ by DAMGO $({\mu}-opioid\;agonist)$ and cholecystokinin octapeptide (CCK-8). In 18 out of 86 cells, the amplitude of $I_{CAP}$ was significantly increased by DAMGO and completely reversed after washout, while $I_{CAP}$ was decreased by DAMGO in 25 cells. In 43 cells, DAMGO had no effect on $I_{CAP}$. Mean action potential duration was significantly different between 'increased-by-DAMGO' group and 'decreased-by-DAMGO' group. Mean amplitudes of $I_H$ were not significantly different between both groups. CCK-8 reversibly enhanced the amplitude of $I_{CAP}$ (5/13). DAMGO also increased $I_{CAP}$ amplitude significantly in the same cells. The amplitude of $I_{CAP}$ was increased in additive manner by combined applications of DAMGO and CCK-8 in these cells. These results suggest that DAMGO and CCK-8 can either increase or decrease $I_{CAP}$ presumably depending on the subtypes of DRG cells and classified by electrophysiological properties.

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A Study on the Cun, Guan, Chi (Inch, Bar, Cubit) from the Elementary Course for Medicine{Yi Xue Ru Men) (의학입문(醫學入門)의 촌관척(寸關尺)에 관한 고찰(考察))

  • Lee, Soo-Kyeung;Park, Won-Hwan
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.9 no.2
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    • pp.10-24
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    • 2005
  • Background and Purpose: Feeling the pulse is based on the pulse condition and alteration to observe the condition of the human body's health and by using a healthy person's pulse as a standard we are able to analyze the patient's pulse to find the attacked channel and collateral, viscera and bowels and understand the pathology such as diseases caused by exogenous evil, disorder of internal organs, and seven modes of emotions. Observing the color and shade of the patient's face, listening carefully to the sound of the patient, and feeling the pulse are methods in accordance with Su Wen 'Plain Questions', 'The Classic on Difficulty' (5th century B.C. Bianque), 'The Classic of Sphymology' (280 A.D. Wang Xi), 'Pulse Formulas' (1189 A.D. Cui Jiayan), and is systematically edited for those who have started studying to easily reach the profound state. Therefore, 'The Elementary Course for Medicine' has been used from ancient times as the textbook for diagnostics. Methods: In this Study, we will inspect commonly used pulse feeling methods, the inch, bar, cubit thesis, the viscera and bowels thesis from The Elementary Course for Medicine and inquire the difference of the text from 'Plain Questions of Huangdi's Internal Classic', 'Treatise on Febrile Diseases', 'Classic on Difficulty'. Results and Conclusion: 1. In 'The Elementary Course for Medicine' the site of the wrist along the pulsation of the radial artery is divided into inch, bar, cubit and has defined the inch, bar, cubit crossways. 2. In 'The Elementary Course of Medicine' the inch, bar, cubit for the left hand and right hand is subjected to each viscera and bowel. By assigning the left hand's inch, bar, cubit to the cardial orb, the hepatic orb, the renal orb, and the right hand's inch, bar, cubit to the pulmonic orb, the splenic orb, the vital gate it has been able to feel the pulse for each viscera and bowel by using the interpromoting and interacting relation of the five evolutive phases.

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A Study on the Attitude of CEO in Private Security Company (시큐리티기업 CEO의 민간경비에 대한 의식조사 연구)

  • Ahn, Hwang-Kwon
    • Korean Security Journal
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    • no.16
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    • pp.119-135
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    • 2008
  • This study is concerned on how much effect to activate private security officers from the attitude of CEO in private security companies. Of course the philosophy of CEO at the work is much important element on the company activity. And in small-medium size private security company the effect of CEO is tremendous because most of decision making comes from CEO and company is operated. The result of the analysis of the survey on the CEO in private security business is as belows. a) Most of them are not satisfied and negative from current situation of private security industry because too many companies are scattered and the expected social understanding is too low even though the company was established by their own decision due to it was fit to their aptitude. b) The job position is estimated not high by socio-economical perspective, which would be improved to get higher because this industry is very future business. c) Most of members of the korea security association are in negative on the policy of the korea security association but to enhance of the activity all the members should be in union. d) Must make and settle down a channel to communicate and cooperate each other between public and private sector of security business.

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A Case of Autosomal Recessive Pseudohypoaldosteronism Type 1 with a Novel Mutation in the SCNN1A Gene (SCNN1A 유전자 변이로 발생한 상염색체 열성 가성 저 알도스테론증 1형 1례)

  • Kim, Su-Yon;Lee, Joo Hoon;Cheong, Hae Il;Park, Young Seo
    • Childhood Kidney Diseases
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    • v.17 no.2
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    • pp.137-142
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    • 2013
  • Pseudohypoaldosteronism (PHA) is a condition characterized by renal salt wasting, hyperkalemia, and metabolic acidosis due to renal tubular resistance to aldosterone. Systemic PHA1 is a more severe condition caused by defective transepithelial sodium transport due to mutations in the genes encoding the ${\alpha}$ (SCNN1A), ${\beta}$ (SCNN1B), or ${\gamma}$ (SCNN1G) subunits of the epithelial sodium channel at the collecting duct, and involves the sweat glands, salivary glands, colon, and lung. Although systemic PHA1 is a rare disease, we believe that genetic studies should be performed in patients with normal renal function but with high plasma renin and aldosterone levels, without a history of potassium-sparing diuretic use or obstructive uropathy. In the present report, we describe a case of autosomal recessive PHA1 that was genetically diagnosed in a newborn after severe hyperkalemia was noted.

Effects of Olanzapine on the Pacemaker Potentials of Interstitial Cells of Cajal in Murine Small Intestine (생쥐 소장 카할세포에서 발생하는 향도잡이 기능의 올란자핀 효능에 관한 연구)

  • Kim, Byung Joo
    • Journal of Life Science
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    • v.29 no.9
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    • pp.1010-1015
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    • 2019
  • The interstitial cells of Cajal (ICCs) are the pacemaker cells in the gastrointestinal (GI) tract. In the present study, the effects of olanzapine, an atypical antipsychotic agent, on pacemaker potentials in cultured ICCs from the small intestine of the mouse were investigated. The whole-cell patch-clamp configuration was used to record pacemaker potentials from cultured ICCs. Olanzapine produced pacemaker depolarizations in a concentration-dependent manner in current clamp mode. Methoctramine, a muscarinic $M_2$ receptor antagonist, did not inhibit olanzapine-induced pacemaker depolarizations, whereas 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) muscarinic $M_3$ receptor antagonist did inhibit it. When guanosine 5'-[${\beta}$-thio] diphosphate (GDP-${\beta}$-S; 1 mM) was in the pipette solution, olanzapine-induced pacemaker depolarization was blocked. Also, low $Na^+$ solution externally eliminated the generation of pacemaker potentials and inhibited the olanzapine-induced pacemaker depolarizations. Additionally, the nonselective cation channel blocker, flufenamic acid, inhibited the olanzapine-induced pacemaker depolarizations. Pretreatment with U-73122, an active phospholipase C (PLC) inhibitor, also eliminated the generation of pacemaker potentials and suppressed the olanzapine-induced pacemaker depolarizations. These results suggested that olanzapine modulates the pacemaker potentials through muscarinic $M_3$ receptor activation by G protein-dependent external $Na^+$ and PLC pathway in the ICCs. Therefore, olanzapine could affect intestinal motility through ICCs.