• Title/Summary/Keyword: Contrast ratio

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Experimental Studies on Cardiac Catecholamine Content (Catecholamines에 관(關)하여 -제삼편(第三編) 심장(心臟) Catecholamines에 관(關)한 실험적(實驗的) 연구(硏究)-)

  • Lee, Woo-Choo
    • The Korean Journal of Pharmacology
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    • v.9 no.1
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    • pp.1-21
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    • 1973
  • During the last decade extensive studios on catecholamines have evolved new knowledge in the physiology and biochemistry of adrenergic mechanism. Cardiac muscle, receiving adrenergic fibres from the stellate, cervical and thoracic ganglia, has been repeatedly shown to have a specific capacity to uptake and to store catecholamines. The catecholamine stores in cardiac muscle have also been shown to be important sites for the action of numerous drugs. Under normal condition, a certain level of catecholamines is maintained in the stores and serves as the basis for studying the changes in the catecholamine content of the heart. Because myocardial catecholamines play such important role in the patho-physiology of the heart, it would be interesting to compare the normal level of myocardial catecholamines among various species of animals. An occasional study has dealt with myocardial catecholamines of several species add ages of animals but these have been insufficiently comprehensive to afford a basis for an understanding of the importance of these amines as related to species and ages. The present investigation was undertaken to determine whether or not there is any significance of myocardial catecholamines in the course of the evolution and development of animals. Seasonal changes, sex difference and regional and subcellular distribution of myocardial catecholamines were also examined. The concentration of cardiac catecholamines was determined by the spectrophotofluorometric procedure described by Shore and Olin. The results obtained were summarized as follows: 1. As animals phylogenetically progressed larger amounts of catecholamines were resent in their hearts. A negligibly small amount of catecholamine was present in the hearts of the clam, a non-vertebrate. Among the vertebrates, cold-blooded animals (snake, turtle, frog, eel and fish) had less myocardial catecholamines than warm-blooded animals, of which aves (fowl and duck) had less than mammalia (cat, dog, rabbit, rat, cow and pig). The ratio of norepinephrine to epinephrine also was greater as the animals progress phylogenetically. 2. Examination of the regional distribution of cardiac catecholamines in warm-blooded animals showed that the content of the auricle was generally higher than that of the septum and considerably than that of the ventricle, but the differences of contents among these regions were not so marked. 3. In the embryonic chick, cardiac catecholamines were firstly detected on the 4th day of incubation, the time before the cardiac innervation of sympathetic nerves. The concentrations of these catecholamines increased but not markedly on the 6th day of incubation, soon after the innervation of sympathetic nerves to the heart. The level of the cardiac catecholamines fluctuated throughout the remainder of embryonic development. 4. In newborn rat hearts, a considerable amount of catecholamines was present. With the development of the rats, the concentrations of myocardial catecholamines increased. The ratio of epinephrine and norepinephrine fluctuated within the range of 40 to 60 pervent. However, as development progressed, the percentage of norepinephrine continued to rise, attaining the adult value of $80{\sim}90%$ after $45{\sim}60$ days. In contrast, the total amount of epinephrine remained fairly constant throughout the animal's development. 5. No significant sexual differences were observed in the concentration of myocardial catecholamines in the developing rat. 6. The catecholamines in the rabbit hearts increased during the summer season (from May to August) and maintained a fairly constant level in the other seasons of the year. 7. The subcellular distribution of cardiac catecholamines was examined by differential centrifugation of homogenates of cardiac muscles in rabbits, cats and rats. The catecholamines were found to be present approximately 20% in particles of mitochondrial fraction, 45% in particles of microsomal fraction and 35% in soluble supernatant fraction. The particle containing catecholamines in cardiac muscle appears to be two different sizes.

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Prevalence of Hypertension and Related Risk Factors of the Older Residents in Andong Rural Area (안동 농촌지역 중년 및 노인 주민의 고혈압 유병율과 위험요인 분석)

  • Lee, Hye-Sang;Kwun, In-Sook;Kwon, Chong-Suk
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.7
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    • pp.852-861
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    • 2009
  • This study was performed to assess the risk factors associated with hypertension from Jan/2003 to Feb/2003. The subjects were 1,296 people (496 males, 800 females) aged 40 years and over living in Andong rural area. The hypertensive group was composed of 602 people (272 males, 330 females), who were diagnosed as hypertension ($SBP{\geq}140\;mmHg$ or $DBP{\geq}90\;mmHg$) for the first time at this health examination. The mean anthropometric values of body weight, body fat (%), body mass index (BMI) and waist circumference were significantly higher in hypertensive group than those in normal group. However, the biochemical measurements such as total-cholesterol (TC), triglyceride (TG), HDL-C, LDL-C and fasting blood glucose (FBG) levels did not show any difference between two groups except TG in female. The risk factors of interest in the development of hypertension were analyzed using the multiple logistic regression and expressed as odds ratio (OR) and 95% confidential interval (CI). The results showed that age, sex, obesity, waist circumference, alcohol drinking and meat intakes were risk factors for hypertension. In contrast, cigarette smoking, exercise and the increased fish, fruit and vegetable (except Kimchi) consumption, blood lipid levels and FBG were not linked with the development of hypertension. Nutrient intakes were not associated with hypertension, either. In conclusion, we cannot assert that this study established the existence of the cause-and-effect relationship between nutrient intakes and risk of hypertension in the subjects, but it does suggest that this is a question worth investigating further using a larger scale of case-control study to determine how the past exposure to some nutrient or dietary component relates to the development of the disease.

Analysis of the Relationships Between ESD and DAP, and Image SNR·CNR According to the Frame Change of Cine Imaging in CAG : With Focus on 10 f/s and 15 f/s (심장혈관 조영술에서 씨네(cine)촬영의 프레임변화에 따른 ESD와 DAP 및 영상의 SNR·CNR 관계 분석: 10f/s과 15f/s을 중심으로)

  • Jung, Myo-Young;Seo, Young-Hyun;Song, Jong-Nam;Han, Jae-Bok
    • Journal of the Korean Society of Radiology
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    • v.12 no.5
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    • pp.669-675
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    • 2018
  • This study aimed to investigate the difference of X-ray exposure by comparing and analyzing entrance surface dose and absorbed dose according to the frame change in coronary angiography using an X-ray machine. Moreover, appropriate frame selection measures for examination, including the effect of frame change on the image quality, were sought by measuring and analyzing the SNR and CNR of the image through image J. The study was conducted on 30 patients (19 males and 11 females) who underwent CAG at this hospital from June 2017 to October 2017. In regard to the patients, their age range was 49-82 years (mean of $65{\pm}9$ years), body weight was 45-91 kg (mean of $67{\pm}8.9kg$), height was 150-179cm (mean of $165.1{\pm}8.9kg$), and BMI was 19.5-30.5(mean of $24.5{\pm}2.9$). For the entrance surface dose and absorbed dose, air kerma value and DAP were obtained and analyzed retrospectively. The SNR and CNR were measured and analyzed through imageJ, and the result values were derived by applying the values to the formula. As for the statistical analyses, the correlations between the entrance surface dose and absorbed dose, and between the SNR and CNR were analyzed by using the SPSS statistical program. The relationship between the entrance surface dose and absorbed dose was not statistically significant for both 10 f/s and 15 f/s (p>0.05). In terms of the relationship between the SNR and CNR, the SNR ($3.374{\pm}2.1297$) and CNR ($0.234{\pm}0.2249$) in 10 f/s were $1.43{\pm}0.4861$ and $0.132{\pm}0.0555$ lower, respectively, than the SNR ($4.929{\pm}2.8532$) and CNR ($0.391{\pm}0.3025$) in 15 f/s, which were not statistically significant (p>0.05). In the correlation analysis, statistically significant results were obtained among the BMI, air kerma, and DAP; between air kerma and DAP; and between SNR and CNR (p<0.001, p<0.001). In conclusion, there was no significant difference between the entrance surface dose and absorbed dose even when the images were taken by changing the frame from 10 f/s to 15 f/s at the time of the coronary angiography. SNR and CNR increased at 15 f/s than at 10 f/s, but they were not statistically significant. Therefore, this study suggests that the concern of the patient and practitioner regarding image quality degradation, as well as the problem of X-ray exposure caused by imaging at 10 f/s and 15 f/s, may be reduced.

Quantitative Evaluation on Optimal Scan Time of PET/CT Studies Using TOF PET (TOF 기법을 이용한 PET/CT 검사에서 적정 스캔 시간에 대한 정량적 평가)

  • Moon, Il-Sang;Lee, Hong-Jae;Kim, Jin-Eui;Kim, Hyun-Joo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.1
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    • pp.34-37
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    • 2012
  • Purpose: To verify the optimal scan time per bed for clinical application, we evaluated the quality of $^{18}F$-FDG images with varying scan times in a phantom and 20 patients with 38 lesions using a Philips (TOF) PET/CT scanner. Materials and Methods: The PET/CT images of a NEMA IEC body phantom and 20 patients (16 males, 4 females) were acquired for 5 different scan times of 20-100 sec per bed with intervals of 20 sec. The activity ratio of hot spheres (diameter of 17 [H1], 22 [H2] and 28 [H3] mm) to the background region in the IEC body phantom was 8-to-1. The contrast recovery coefficient (CRC) and standard uptake value (SUV) based on ROIs of hot spheres and background region were calculated. The noise in each background region was estimated as the ratio of SD of counts to the mean counts in the background region. On the patient image, the injected dose of $^{18}F$-FDG was $444{\pm}74$ MBq and the SUVs in the 38 hot lesions were measured. Results: The two scan time groups (LT-60 [<60 sec] and GT-60 [${\geq}60$ sec]) were compared. In the phantom study, the coefficient of deviations (CVs, %) of CRC and SUV in LT-60 (H1: 14.2 and 7.3, H2: 11.4 and 7.8, H3: 4.9 and 3.2) were higher than GT-60 (H1: 8.9 and 2.8, H1: 8.2 and 5.0, H3: 2.0 and 1.6). In the patient study, the mean CV of CRC and SUV in LT-60 (4.0) was higher than GT-60 (1.2). Conclusion: This study showed that noise increased as the scan time decreased. High noise for the scan time <60 sec per bed yielded high variation of SUV and CRC. Therefore, considering PET/CT image quality, the scan time per bed in the TOF PET/CT scanner should be at least ${\geq}60$ sec.

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Predicting the Nutritional Value of Seafood Proteins as Measured by Newer In Vitro Model -1. C-PER and DC-PER of Shellfish Proteins- (수산식품단백질 품질평가를 위한 새로운 모델 설정 -1. 패류의 C-PER 및 DC-PER-)

  • Ryu, Hong-Soo;Lee, Kang-Ho;Kim, Jang-Yang;Choi, Byeong-Dae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.14 no.3
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    • pp.265-273
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    • 1985
  • To predict the nutritional quality of seafood proteins using a newer in virto model, 10 species of shellfish protein samples were used in determining the extent of in vitro digestibility, trypsin indigestible substrate (TIS), computed protein efficiency ratio (C-PER), discriminant computed protein efficiency ratio (DC-PER) and predicted digestibility which calculated solely from amino acid profile. The content of TIS in eviscerated samples were ranged from 1.10 to 5.09 mg/g solid, whereas the whole samples were ranged from 1.26 to 7.30 mg/g solid expressed quantitatively as mg of soybean trypsin inhibitor. The in vitro digestibility showed $82{\sim}86%$ for eviscerated samples in contrast with $78{\sim}84%$ for whole ones. Therefore, the results suggested that in vitro digestibility of shellfish was influenced by the present of viscera. The lysine content of Mya arenaria, Saxidomus purpuratus, Anadara subcrenata, and Anadara broughronii were lower than that of ANRC casein, but Corbicula fluminea, Cyclina sinensis, and eviscerated Mytilus edulis, were showed the value about 10.0 g/16g N. In all samples, the content of tryptophan and cystein were more higher than those of ANRC casein. The C-PER of whole samples showed the value below 2.0 while the values above 2.5 noted in the eviscerated samples. DC-PER of most samples were greater than those of C-PER and a greater discrepancies were revealed in whole shellfish which possesses the lower in vitro digestibility. The shellfish sample showed a high in vitro digestibility and a low TIS content such as eviscerated ones may need the DC-PER and predicted digestibility procedures rather than C-PER and four-enzyme in vitro digestibility procedure could offer more advantages in predicting the protein quality of whole shellfish samples which have poor in vitro digestibility and high TIS content.

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Detection of Hepatic Lesion: Comparison of Free-Breathing and Respiratory-Triggered Diffusion-Weighted MR imaging on 1.5-T MR system (국소 간 병변의 발견: 1.5-T 자기공명영상에서의 자유호흡과 호흡유발 확산강조 영상의 비교)

  • Park, Hye-Young;Cho, Hyeon-Je;Kim, Eun-Mi;Hur, Gham;Kim, Yong-Hoon;Lee, Byung-Hoon
    • Investigative Magnetic Resonance Imaging
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    • v.15 no.1
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    • pp.22-31
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    • 2011
  • Purpose : To compare free-breathing and respiratory-triggered diffusion-weighted imaging on 1.5-T MR system in the detection of hepatic lesions. Materials and Methods: This single-institution study was approved by our institutional review board. Forty-seven patients (mean 57.9 year; M:F = 25:22) underwent hepatic MR imaging on 1.5-T MR system using both free-breathing and respiratory-triggered diffusion-weighted imaging (DWI) at a single examination. Two radiologists retrospectively reviewed respiratory-triggered and free-breathing sets (B50, B400, B800 diffusion weighted images and ADC map) in random order with a time interval of 2 weeks. Liver SNR and lesion-to-liver CNR of DWI were calculated measuring ROI. Results : Total of 62 lesions (53 benign, 9 malignant) that included 32 cysts, 13 hemangiomas, 7 hepatocellular carcinomas (HCCs), 5 eosinophilic infiltration, 2 metastases, 1 eosinophilic abscess, focal nodular hyperplasia, and pseudolipoma of Glisson's capsule were reviewed by two reviewers. Though not reaching statistical significance, the overall lesion sensitivities were increased in respiratory-triggered DWI [reviewer1: reviewer2, 47/62(75.81%):45/62(72.58%)] than free-breathing DWI [44/62(70.97%):41/62(66.13%)]. Especially for smaller than 1 cm hepatic lesions, sensitivity of respiratory-triggered DWI [24/30(80%):21/30(70%)] was superior to free-breathing DWI [17/30(56.7%):15/30(50%)]. The diagnostic accuracy measuring the area under the ROC curve (Az value) of free-breathing and respiratory-triggered DWI was not statistically different. Liver SNR and lesion-to-liver CNR of respiratory-triggered DWI ($87.6{\pm}41.4$, $41.2{\pm}62.5$) were higher than free-breathing DWI ($38.8:{\pm}13.6$, $24.8{\pm}36.8$) (p value < 0.001, respectively). Conclusion: Respiratory-triggered diffusion-weighted MR imaging seemed to be better than free-breathing diffusion-weighted MR imaging on 1.5-T MR system for the detection of smaller than 1 cm lesions by providing high SNR and CNR.

Chemo-Mechanical Analysis of Bifunctional Linear DGEBA/Linear Amine (DDM, DDS) Resin Casting Systems (DGEBA/방향족 아민(DDM, DDS) 경화제의 벤젠링 사이의 관능기 변화가 물성 변화에 미치는 영향에 대한 연구)

  • 명인호;정인재;이재락
    • Composites Research
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    • v.12 no.4
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    • pp.71-78
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    • 1999
  • To determine the effect of chemical structure of linear amine curing agents on thermal and mechanical properties, standard epoxy resin DGEBA was cured with diaminodiphenyl methane (DDM), diaminodiphenyl sulphone (DDS) in a stoichiometrically equivalent ratio. From this work, the effect of aromatic amine curing agents. In contrast, the results show that the DGEBA/DDS cure system having the sulfone structure between the benzene rings had higher values in the conversion of epoxide, density, shrinkage (%), glass transition temperature, tensile modulus and strength, flexural modulus and strength than the DGEBA/DDM cure system having methylene structure between the benzene rings, whereas the DGEBA/DDM cure system presented higher values in the maximum exothermic temperature, thermal expansion coefficient, and thermal stability. These results are caused by the relative effects of sulfone group having strong electronegativity and methylene group having (+) repulsive property and stem from the effect of the conversion ratio of epoxide group. The result of fractography shows that the each grain size of the DDM/DGEBA system with feather-like structure is larger than that of the DDS/DGEBA system.

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Improvement of Rice Quality Using Grain Color Sorter During Early Transplanting Cultivation in the Southern Plain of Korea (색채선별기 이용한 남부평야지 조기재배 해담쌀의 품질향상)

  • Lee, Jong-Hee;Lee, Ji-Yoon;Lee, Somyeong;Shin, Dongjin;Cha, Jinkyeong;Cho, Jun-Hyeon;Kwon, Young-Ho;Jo, Su-min;Park, Dong-Soo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.65 no.2
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    • pp.79-83
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    • 2020
  • A photoelectric grain color sorter is commonly used in postharvest technology to detect and separate grains considered to be of good quality from those of poor quality based on color. In this study, the milled rice of Haedamssal cultivated under early transplanting conditions was evaluated using the color sorting device. Rice was classified according to standard grades of 64% for grade A, 18% for grade B, and 17.2% for grade C. By head rice ratio analysis, the milled rice of Haedamssal was recorded a grade A of 72.9%, representing a 24.5% improvement compared to the 48.4% of original grains. However, the grades B and C of Haedamssal rice were lower than those of original rice. In addition, grade A whiteness of Haedamssal rice was 45.3, which was lower than that of original grains. The color affinity redness was significantly lower in Haedamssal rice than in the screening control. No significant difference was found in the amylose and protein contents of rice before and after selection by the grain color sorter. In contrast, grain viscosity analysis revealed an increase in peak and final viscosities, while the consistence viscosity increased in low grade levels. Our results suggest that the photoelectric grain color sorter could improve the head rice ratio and palatability of early transplanted Hadamssal rice.

Prevalence of Arthritis and Health Behavior Related Risk Factors of the Older Residents in Andong Rural Area (안동 농촌지역 중년 및 노인 주민의 관절염 유병율과 건강습관 관련 위험요인 분석)

  • Lee, Hye-Sang;Kwon, Chong-Suk
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.9
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    • pp.1187-1194
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    • 2009
  • This study was performed to estimate the prevalence and the risk factors of arthritis in Andong rural area in 2003. The subjects were 1,462 people (544 males, 818 females) aged 45 years and over. The arthritis group was composed of 322 people (72 males, 250 females), diagnosed by doctor or self-diagnosed by the symptoms. Prevalence of arthritis was higher in female (27.2%) compared to male (13.2%). Mean age of arthritis group was significantly higher than that of normal group (male 66.2 vs 62.8, female 62.6 vs 60.1, p<0.001). The anthropometric measurements, such as % body fat, body mass index (BMI), and waist circumference, and the biochemical measurements, such as plasma triglyceride and total cholesterol level, were significantly higher only in female (not in male) arthritis group than those in normal group. Health related lifestyle factors, such as smoking, alcohol drinking, and exercise, were not different between both groups. The risk factors for arthritis were analyzed using the multiple logistic regression method and expressed as odds ratio (OR). The results showed that female compared to male (OR=1.983), over 65 years compared to 45$\sim$64 years (male OR=2.769 and female OR=1.461), and obese female subjects (not for male) by % body fat ($\geq$32% OR=2.035) or BMI ($\geq$25 kg/$m^2$ OR=1.556) showed significantly higher risk factors for arthritis. Regarding nutrient intakes, higher intakes of fat (OR=1.443), calcium (OR=1.503), iron (OR=1.518) and vitamin A (OR=1.390) in female seemed to be risk factors. In contrast to female, higher intakes of vitamin A (OR=0.526) and riboflavin (OR=0.582) seemed to decrease the risk for arthritis in male. This study revealed that the prevalence of arthritis was significantly higher in female and aged individuals. Also, in order to decrease the prevalence and/or prevention of arthritis, female should prevent overfatness and decrease some nutrient intakes, while male should increase their intakes.

Shallow Subsurface Structure of the Yaksoo Area, Ulsan, Korea by Geophysical Surveys (물리탐사기법에 의한 울산광역시 약수지역 천부지하구조 조사)

  • Lee, Jung-Mo;Kong, Young-Sae;Chang, Tae-Woo;Park, Dong-Hee;Kim, Tae-Kyung
    • Journal of the Korean Geophysical Society
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    • v.3 no.1
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    • pp.57-66
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    • 2000
  • The location and geometry of the Ulsan Fault play important roles in interpreting tectonic evolution of the southeastern part of the Korean Peninsula. Dipole-dipole electrical resistivity surveys and seismic refraction surveys were carried out in the Yaksoo area, Ulsan in order to measure the thickness of the alluvium covering the Ulsan Fault and to find associated fracture zones and possibly the location of its major fault plane. The collected data were analyzed and interpreted. Some results reported previously by others were also used in this interpretation. No low resistivity anomalies were found in the cross-sectional resistivity image of the survey line located in the east of the Dong River. In contrast, well-developed continuous low resistivity anomalies were detected in the west of the Dong River. This strongly suggests that the major fault plane of the Ulsan Fault is located under or in the west part of the Dong River. Two refraction boundaries corresponding to the underground water level and the bottom of the alluvium were found by refraction surveys carried out on the limited part of the east survey line. The thickness of the alluvium was found to be about 30 m. Small faults in the basement rock identified by reflection surveys were not detected by both resistivity and refraction seismic surveys. This might be explained by assuming that low resistivity anomaly is more closely related to the clay contents than the water contents. On the other hand, it may be resulted by the limited resolution of the resistivity and refraction surveys. Detailed study is required to clarify the reason. Resistivity survey is frequently considered to be a good exploration method to detect subsurface faults. However, it appears to be less useful than reflection seismic survey in this work. In dipole-dipole resistivity survey, the number of separation should be increased to survey deeper subsurface with the same resolution. However, signal to noise ratio decreases as the number of separation increases. In this survey area, the signal to noise ratio of up to sixteen separations was good enough based on the statistical properties of measurements.

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