• Title/Summary/Keyword: Development mechanism

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Isocyanate-Induced Occupational Asthma: Immunologic and Challenge Studies (Isocyanate에 의한 직업성 천식환자에서 임상양상과 Isocyanate 특이 IgE 항체에 관한 연구)

  • Suh, Jung-Eun;Park, Hae-Sim;Kim, Seong-Jin;Rhu, Nam-Soo;Cho, Dong-Ill;Kim, Jae-Won;Kyung, Nan-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.39 no.6
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    • pp.490-501
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    • 1992
  • Background: Isocyanate is the most significant cause of occupational asthma in this country. The mechanism of isocyanate induced bronchoconstriction is unclear. Subjects and Method: To observe its immunologic and clinical findings, we performed methacholine bronchial challenge test (MBCT), toluene diisocyanate (TDI)-bronchoprovocation test (BPT) and RAST to TDI-, diphenylmethane diisocyanate (MDI)-, and hexamethylene diisocyanate (HDI)-human serum albumin (HSA) conjugate in 22 isocyanate-sensitive asthmatic workers. Results: BPT revealed early (11), dual (5), and late only (6) asthmatic responses. Their latent period ranged from 3 to 120 months (mean:45.9 months). Three cases (13.6%)showed a negative response on initial MBCT, but following MBeT performed 24 hours after TDI-BPT revealed the development of airway hyperresponsivenss. Twelve (54.5%) workers had increased specific IgE to TDI-HSA, seven (31.8%) had to MDI-HSA, and nine (40.9%) had to HDI-HSA conjugate. The prevalence of specific IgE was not associated with latent period, type of asthmatic responses, smoking, and atopic status. After 3 months' avoidance from workplace, airway hyperresponsiveness was improved in 10 (38.3%), among 12 followed cases. Conclusion: It is suggested that isocyanate can induce IgE-mediated bronchoconstriction in 59.1% of isocyanate-sensitive asthmatic workers. Isocyanate-induced asthma can occur even though MBeT showed a negative result, and measurement of the changes of airway hyperresponsivenss after isocyanate-BPT could be helpful to diagnose isocyanate-sensitive asthma.

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The Change of Antioxidant Enzyme (Superoxide Dismutase, Catalase, Glutathione Peroxidase) in the Endotoxin Infused Rat Lung (내독소 투여후 쥐의 폐조직내 Antioxidant (Superoxide Dismutase, Catalase, GSH-Peroxidase)의 변화에 대한 연구)

  • Song, Jeong-Sup;Kim, Chi-Hong;Kwon, Soon-Seog;Kim, Young-Kyoon;Kim, Kwan-Hyoung;Han, Ki-Don;Moon, Hwa-Sik;Park, Sung-Hak
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.2
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    • pp.104-111
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    • 1993
  • Background: Gram-negative bacterial endotoxin induced septicemia is known to be a leading cause in the development of adult respiratory distress syndrome(ARDS). The mechanism of endotoxin induced lung injury is mainly due to the activated neutrophils which injure the capillary endothelial cells by releasing oxidant radical and resulted in pulmonary edema. We studied the change of antioxidant enzyme in the case of large or small, intermittant dose of endotoxin infused rat lungs. Methods: Endotoxin was given to the rat through the peritoneal cavity in the dose of 7 mg/kg body weight in the large dose group and 1 mg/kg for 10 days in the small dose group. Bronchoalveolar lavage (BAL) was done and rats were killed at 6, 12, 24 hours after single endotoxin injection in the large dose group and 3, 7, 10 days after daily endotoxin injection for 10 days in the small dose group. The lungs were perfused with normal saline through the pulmonary artery to remove the blood and were homogenized in 5 volume of 50 mM potassium phosphate buffer containing 0.1 mM EDTA. After centrifuging at 100,000 g for 60 minute, the supernatent was removed and stored at $-70^{\circ}C$ until measuring for superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px) and protein. Results: We observed the following results. 1) The lung wet/dry weight ratio and albumin concentration in the BAL fluids were increased to peak at 12 hours and neutrophil number in the BAL fluids were peak at 6 hours after endotoxin injection in the large dose group. 2) Cu, Zn SOD (IU/mg protein) was significantly decreased after 6, 12 hours after endotoxin injection in the large dose group. 3) There were no singnificant change in the level of Mn SOD, catalase, GSH-Px after endotoxin injection in both groups. Conclusion: Endotoxin in the large dose group produced the acute pulmonary edema and decreased the Cu, Zn SOD in the lung tissue after injecting endotoxin at 6 and 12 hours. These phenomenon may be due to the cell membrane damage by endotoxin. Further research would be necessary whther giving SOD by intratracheal route or method to increase the synthesis of SOD may lessen the acute lung injury by endotoxin.

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Detection with a SWNT Gas Sensor and Diffusion of SF6 Decomposition Products by Corona Discharges (탄소나노튜브 가스센서의 SF6 분해생성물 검출 및 확산현상에 관한 연구)

  • Lee, J.C.;Jung, S.H.;Baik, S.H.
    • Journal of the Korean Vacuum Society
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    • v.18 no.1
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    • pp.66-72
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    • 2009
  • The detection methods are required to monitor and diagnose the abnormality on the insulation condition inside a gas-insulated switchgear (GIS). Due to a good sensitivity to the products decomposed by partial discharges (PDs) in $SF_6$ gas, the development of a SWNT gas sensor is actively in progress. However, a few numerical studies on the diffusion mechanism of the $SF_6$ decomposition products by PD have been reported. In this study, we modeled $SF_6$ decomposition process in a chamber by calculating temperature, pressure and concentration of the decomposition products by using a commercial CFD program in conjunction with experimental data. It was assumed that the mass production rate and the generation temperature of the decomposition products were $5.04{\times}10^{-10}$ [g/s] and over 773 K respectively. To calculate the concentration equation, the Schmidt number was specified to get the diffusion coefficient functioned by viscosity and density of $SF_6$ gas instead rather than setting it directly. The results showed that the drive potential is governed mainly by the gradient of the decomposition concentration. A lower concentration of the decomposition products was observed as the sensors were placed more away from the discharge region. Also, the concentration increased by increasing the discharge time. By installing multiple sensors the location of PD is expected to be identified by monitoring the response time of the sensors, and the information should be very useful for the diagnosis and maintenance of GIS.

Role of PKR and EGR-1 in Induction of Interleukin-S by Type B Trichothecene Mycotoxin Deoxynivalenol in the Human Intestinal Epithelial Cells (B형 트리코테센 곰팡이 독소 데옥시니발레놀에 의한 인체 장관 상피세포 염증성 인터루킨 8유도에서의 PKR과 EGR-1의 상호 역할 규명)

  • Park, Seong-Hwan;Yang, Hyun;Choi, Hye-Jin;Park, Yeong-Min;Ahn, Soon-Cheol;Kim, Kwan-Hoi;Lee, Soo-Hyung;Ahn, Jung-Hoon;Chung, Duk-Hwa;Moon, Yu-Seok
    • Journal of Life Science
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    • v.19 no.7
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    • pp.949-955
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    • 2009
  • Mucosal epithelia sense external stress signals and transmit them to the intracellular cascade responses. Ribotoxic stress-producing chemicals such as deoxynivalenol (DON) or other trichothecene mycotoxins have been linked with gastrointestinal inflammatory diseases by Fusarium-contamination. The purpose of this study was to test the hypothesis that DON evokes the epithelial sentinel signals of RNA-dependent protein kinase (PKR) and early growth response gene 1 (EGR-1), which together contribute to the pro-inflammatory cytokine interleukin 8 (IL-8) in human intestinal epithelial cells. PKR suppression by the dominant negative PKR expression attenuated DON-stimulated interleukin-8 production. Moreover, 1L-8 transcriptional activation by DON was also reduced by PKR inhibition in the human intestinal epithelial cells. Treatment with the PKR inhibitor also suppressed EGR-1 promoter activity, mRNA and protein induction, although mitogen-activated protein (MAP) kinases such as extracellular signal-regulated protein kinases (ERK) 1/2, p38, c-Jun N-terminal Kinase (INK) were little affected or even enhanced in presence of a PKR inhibitor. These patterns were also compared in the EGR-1-suppressed cells, which showed much more suppressed production of 1L-8. All things taken into consideration, DON-activated sentinel signals of EGR-1 via PKR mediated interleukin-8 production in human intestinal epithelial cells, which provide insight into the possible general mechanism associated with mucosal inflammation as an intestinal toxic insult by ribotoxic trichothecene mycotoxins.

Effect of Ethane 1,2-Dimethane Sulfonate(EDS) on the Apoptosis in the Rat Epididymis (흰쥐 부정소에서의 세포자연사에 미치는 Ethane 1,2-Dimethane Sulfonate(EDS)의 효과)

  • Son, Hyeok-Jun;Lee, Sung-Ho
    • Development and Reproduction
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    • v.10 no.3
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    • pp.203-209
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    • 2006
  • Ethane 1,2-Dimethane sulfonate(EDS), a toxin which specifically kills Leydig cells(LC), has been widely used to prepare the reversible testosterone(T) depletion rat model. Previous studies including our own clearly demonstrated that the dramatic weight loss of the T-dependent accessory sex organs such as epididymis and seminal vesicle in this 'LC knock-out' rats. These weight loss could be derived from massive and abrupt death of the cells via apoptotic process. The present study was performed to test the effect of EDS administration on the expression of some apoptotic genes in the rat epididymis. Adult male Sprague-Dawley rats($300{\sim}350$ g B.W.) were injected with single dose of EDS(75 mg/kg, i.p.) and sacrificed on Weeks 0, 1, 2, 3, 4, 5, 6 and 7. Tissue weights and the numbers of the epididymal sperm were measured. The transcriptional activities of the bcl-2, bax, Fas and Fas ligand(Fas-L) were evaluated by semi-quantitative RT-PCR. As expected, the weights and the sperm counts of epididymis declined progressively after the EDS treatment during Week 1 and 2. These decrements were discontinued with a gradual return towards normal during Weeks $5{\sim}7$, although the maximal recoveries of the epididymal weights(71%) and sperm count(38%) were subnormal on Week 7. The initial level of bcl-2 transcripts persisted to Week 6 then elevated significantly on Week 7. The level of bax transcripts significantly decreased on Week 6, and no remarkable change was found in the rest of the experimental period. The transcripts for the Fas in epididymis elevated during Weeks $1{\sim}2$, returned to normal on Week 3, and the level persisted to the Week 7. Similarly, the level of Fas-L transcripts elevated during Weeks $1{\sim}3$ and returned to normal after Week 4. Our results demonstrated the transient T depletion by EDS administration could induce the changes in expression of the apoptotic genes in rat epididymis. The activation of Fas and Fas-L in the epididymis of EDS-treated rats might be responsible for the initial apototic process and consequently the tissue damage and the sperm loss. Future studies will attempt to determine the precise molecular mechanism(s) of apoptosis in the rat epididymis.

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Comparison of Acting Style Between 2D Hand-drawn Animation and 3D Computer Animation : Focused on Expression of Emotion by Using Close-up (2D 핸드 드로운 애니메이션과 3D 컴퓨터 애니메이션에서의 액팅(acting) 스타일 비교 -클로즈-업을 이용한 감정표현을 중심으로-)

  • Moon, Jaecheol;Kim, Yumi
    • Cartoon and Animation Studies
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    • s.36
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    • pp.147-165
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    • 2014
  • Around the turn of 21st century, there has been a major technological shift in the animation industry. With development of reality-based computer graphics, major American animation studios replaced hand-drawn method with the new 3D computer graphics. Traditional animation was known for its simplified shapes such as circles and triangle that makes characters' movements distinctive from non-animated feature films. Computer-generated animation has largely replaced it, but is under continuous criticism that automated movements and reality-like graphics devaluate the aesthetics of animation. Although hand-drawn animation is still produced, 3D computer graphics have taken commercial lead and there has been many changes to acting of animated characters, which calls for detailed investigation. Firstly, the changes in acting of 3D characters can be traced from looking at human-like rigging method that mimics humanistic moving mechanism. Also, if hair and clothing was part of hand-drawn characters' acting, it has now been hidden inside mathematical simulation of 3D graphics, leaving only the body to be used in acting. Secondly, looking at "Stretch and Squash" method, which represents the distinctive movements of animation, through the lens of media, a paradox arises. Hand-drawn animation are produced frame-by-frame, and a subtle change would make animated frames shiver. This slight shivering acts as an aesthetic distinction of animated feature films, but can also require exaggerated movements to hide the shivering. On the contrary, acting of 3D animation make use of calculated movements that may seem exaggerated compared to human acting, but seem much more moderate and static compared to hand-drawn acting. Moreover, 3D computer graphics add the third dimension that allows more intuitive movements - maybe animators no longer need fine drawing skills; what they now need is directing skills to animate characters in 3D space intuitively. On the assumption that technological advancement and change of artistic expressionism are inseparable, this paper compares acting of 3D animation studio Pixar and classical drawing studio Disney to investigate character acting style and movements.

Status of Brain-based Artistic Education Fusion Study - Basic Study for Animation Drawing Education (뇌기반 예술교육 융합연구의 현황 - 애니메이션 드로잉 교육을 위한 기초연구)

  • Lee, Sun Ju;Park, Sung Won
    • Cartoon and Animation Studies
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    • s.36
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    • pp.237-257
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    • 2014
  • This study is the process of performing the interdisciplinary fusion study between multiple fields by identifying the status on the previous artistic education considering the brain scientific mechanism of image creativity and brain-based learning principles. In recent years, producing the educational methods of each field as the fusion study activities are emerging as the trend and thanks to such, the results of brain-based educational fusion studies are being presented for each field. It includes artistic fields such as music, art and dance. In other words, the perspective is that by understanding the operating principles of the brain while creativity and learning is taking place, when applying various principles that can develop the corresponding functions as a teaching method, it can effectively increase the artistic performance ability and creativity. Since the animation drawing should be able to intuitively recognize the elements of movement and produce the communication with the target beyond the delineative perspective of simply drawing the objects to look the same, it requires the development of systematic educational method including the methods of communication, elements of higher cognitive senses as well as the cognitive perspective of form implementation. Therefore, this study proposes a literature study results on the artistic education applied with brain-based principles in order to design the educational model considering the professional characteristics of animation drawing. Therefore, the overseas and domestic trends of the cases of brain-based artistic education were extracted and analyzed. In addition, the cases of artistic education studies applied with brain-based principles and study results from cases of drawing related education were analyzed. According to the analyzed results, the brain-based learning related to the drawing has shown a common effect of promoting the creativity and changes of positive emotion related to the observation, concentration and image expression through the training of the right brain. In addition, there was a case of overseas educational application through the brain wave training where the timing ability and artistic expression have shown an enhancement effect through the HRV training, SMR, Beta 1 and neuro feedback training that strengthens the alpha/seta wave and it was proposing that slow brain wave neuro feedback training contributes significantly in overcoming the stress and enhancing the creative artistic performance ability. The meaning of this study result is significant in the fact that it was the case that have shown the successful application of neuro feedback training in the environment of artistic live education beyond the range of laboratory but the use of the machine was shown to have limitations for being applied to the teaching methods so its significance can be found in providing the analytical foundation for applying and designing the brain-based learning principles for future animation drawing teaching methods.

THE CHANGE OF THE INITIAL DYNAMIC VISCO-ELASTIC MODULUS OF COMPOSITE RESINS DURING LIGHT POLYMERIZATION (광중합 복합레진의 중합초기 동적 점탄성의 변화)

  • Kim, Min-Ho;Lee, In-Bog
    • Restorative Dentistry and Endodontics
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    • v.34 no.5
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    • pp.450-459
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    • 2009
  • The aim of this study was to measure the initial dynamic modulus changes of light cured composites using a custom made rheometer. The custom made rheometer consisted of 3 parts: (1) a measurement unit of parallel plates made of glass rods, (2) an oscillating shear strain generator with a DC motor and a crank mechanism, (3) a stress measurement device using an electromagnetic torque sensor. This instrument could measure a maximum torque of 2Ncm, and the switch of the light-curing unit was synchronized with the rheometer. Six commercial composite resins [Z-100 (Z1), Z-250 (Z2), Z-350 (Z3), DenFil (DF), Tetric Ceram (TC), and Clearfil AP-X (CF)] were investigated. A dynamic oscillating shear test was undertaken with the rheometer. A certain volume ($14.2\;mm^3$) of composite was loaded between the parallel plates, which were made of glass rods (3 mm in diameter). An oscillating shear strain with a frequency of 6 Hz and amplitude of 0.00579 rad was applied to the specimen and the resultant stress was measured. Data acquisition started simultaneously with light curing, and the changes in visco-elasticity of composites were recorded for 10 seconds. The measurements were repeated 5 times for each composite at $25{\pm}0.5^{\circ}C$. Complex shear modulus G*, storage shear modulus G', loss shear modulus G" were calculated from the measured strain-stress curves. Time to reach the complex modulus G* of 10 MPa was determined. The G* and time to reach the G* of 10 MPa of composites were analyzed with One-way ANOVA and Tukey's test ($\alpha$ = 0.05). The results were as follows. 1. The custom made rheometer in this study reliably measured the initial visco-elastic modulus changes of composites during 10 seconds of light curing. 2. In all composites, the development of complex shear modulus G* had a latent period for $1{\sim}2$ seconds immediately after the start of light curing, and then increased rapidly during 10 seconds. 3. In all composites, the storage shear modulus G" increased steeper than the loss shear modulus G" during 10 seconds of light curing. 4. The complex shear modulus of Z1 was the highest, followed by CF, Z2, Z3, TC and DF the lowest. 5. Z1 was the fastest and DF was the slowest in the time to reach the complex shear modulus of 10 MPa.

Studies on the Nitrogen Metabolism of Soybeans -III. Variation of Glutamic acid, Aspartic acid and its Amides during the Growth of Yonger Plants (대두(大豆)의 질소대사(窒素代謝)에 관(關)한 연구(硏究) -III. 유식물(幼植物) 시기(時期)에서의 Glutamine 산(酸)과 Asparagine 산(酸) 및 그 Amide의 소장(消長))

  • Kang, Y.H.
    • Korean Journal of Soil Science and Fertilizer
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    • v.3 no.1
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    • pp.55-59
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    • 1970
  • In an effort to determine the bio-synthesis in the soybean as investigate to the variance of each substance: Glutamic acid, Aspartic acid and its amides during the growth of younger soybean plants. 1. The variance-curve of Gultamic acid and Aspartic acid as the acidic amino acids in the cotyledons was appeared the peak the first half period at Glutamic acid and the latter half at Aspartic acid in the growth of soybeans, and was received the symmetrical impression centering around the stage of adult leaf-development. But, in the embryonic organ, it appears the peak at both part, in the developmental stage of adult leaf and also appears near phenomena of increase and decrease in the variation-curve of metabolites. 2. It's amides-Gultamine and Asparagine-appears the peak at the developmental stage of adult leaf in the both cotyledons and embryonic organ, and rapid increase in the cotyledons were very impressed compare with the decrease at fallen stage of cotyledons in the embryonic organs. 3. In the relation of variance at Glutamic acid and Aspartic acid, both substance were discovered the fact of translocation from cotyledon to embryonic organ, and Glutamic acid could supposed that bear the charges of outrider substance in other amino acid as the Glutamic acid-self and major basic function for receiving the ammonia as the nitrogen contain constituent of plant. In the case of Glutamine, formation-mechanism of ammonia which develops due to its hydrolysis in the latter period of soybean growth, suggested that was forfeit its function till instance of fallen cotyledons. 4. In the relation the Aspartie acid and Asparagine, Aspartic acid which begins to decrease from seed-state was supposed that bear sufficiently the charge of outrider substance in the formation of Asparagine other than translocated to embryonic organ from cotyledon. And, formation-theory of Aspartic acid which suppose as formational substance from Kreb's cycle were recognized from latter period of soybean growth, and then, rapid accumulation of Asparagine's amounts were supposed that adapt to two theory: Theory which consider to transformation as Asparagine state for pressing to less than noxious weight the concentration of ammonia developing from the cells, and was formate and accumulate as ammonia or carbohydrates containing excess in the cotyledons.

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Hydrogeochemical Characterization of Groundwater in Jeju Island using Principal Component Analysis and Geostatistics (주성분분석과 지구통계법을 이용한 제주도 지하수의 수리지화학 특성 연구)

  • Ko Kyung-Seok;Kim Yongie;Koh Dong-Chan;Lee Kwang-Sik;Lee Seung-Gu;Kang Cheol-Hee;Seong Hyun-Jeong;Park Won-Bae
    • Economic and Environmental Geology
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    • v.38 no.4 s.173
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    • pp.435-450
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    • 2005
  • The purpose of the study is to analyze the hydrogeochemical characteristics by multivariate statistical method, to interpret the hydrogeochemical processes for the new variables calculated from principal components analysis (PCA), and to infer the groundwater flow and circulation mechanism by applying the geostatistical methods for each element and principal component. Chloride and nitrate are the most influencing components for groundwater quality, and the contents of $NO_3$ increased by the input of agricultural activities show the largest variation. The results of PCA, a multivariate statistical method, show that the first three principal components explain $73.9\%$ of the total variance. PC1 indicates the increase of dissolved ions, PC2 is related with the dissolution of carbonate minerals and nitrate contamination, and PC3 shows the effect of cation exchange process and silicate mineral dissolution. From the results of experimental semivariogram, the components of groundwater are divided into two groups: one group includes electrical conductivity (EC), Cl, Na, and $NO_3$, and the other includes $HCO_3,\;SiO_2,$ Ca, and Sr. The results for spatial distribution of groundwater components showed that EC, Cl, and Na increased with approaching the coastal line and nitrate has close relationship with the presence of agricultural land. These components are also correlated with the topographic features reflecting the groundwater recharge effect. The kriging analysis by using principal components shows that PC 1 has the different spatial distribution of Cl, Na, and EC, possibly due to the influence of pH, Ca, Sr, and $HCO_3$ for PC1. It was considered that the linear anomaly zone of PC2 in western area was caused by the dissolution of carbonate mineral. Consequently, the application of multivariate and geostatistical methods for groundwater in the study area is very useful for determining the quantitative analysis of water quality data and the characteristics of spatial distribution.