• Smart Structures and Systems
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• v.33 no.2
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• pp.93-103
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• 2024

Despite the rapid development of sensors, structural health monitoring (SHM) still faces challenges in monitoring due to the degradation of devices and harsh environmental loads. These challenges can lead to measurement errors, missing data, or outliers, which can affect the accuracy and reliability of SHM systems. To address this problem, this study proposes a classification method that detects anomaly patterns in sensor data. The proposed classification method involves several steps. First, data scaling is conducted to adjust the scale of the raw data, which may have different magnitudes and ranges. This step ensures that the data is on the same scale, facilitating the comparison of data across different sensors. Next, informative features in the time and frequency domains are extracted and used as input for a deep neural network model. The model can effectively detect the most probable anomaly pattern, allowing for the timely identification of potential issues. To demonstrate the effectiveness of the proposed method, it was applied to actual data obtained from a long-span cable-stayed bridge in China. The results of the study have successfully verified the proposed method's applicability to practical SHM systems for civil infrastructures. The method has the potential to significantly enhance the safety and reliability of civil infrastructures by detecting potential issues and anomalies at an early stage.

• Economic and Environmental Geology
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• v.19 no.spc
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• pp.19-41
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• 1986

Structural, radioactive, petrological, petrochemical, mineralogical and stable isotopic study as well as the review of previous studies of the uranium-bearing slates in the Ogcheon sequence were carried out to examine the lithological and structural controls, and geochemical environment in the uranium deposition in the sequence. And the study was extended to the coal-bearing formation (Jangseong Series-Permian) to compare the geochemical and sedimentologic aspects of uranium chemistry between Ogcheon and Hambaegsan areas. The results obtained are as follows: 1. The uranium mineralization occurs in the carbonaceous black slates of the middle to lower Guryongsan formation and its equivalents in the Ogcheon sequence. In general, two or three uranium-bearing carbonaceous beds are found with about 1 to 1.5km stratigraphic interval and they extend from Chungju to Jinsan for 90km in distance, with intermittent igneous intrusions and structural Jisturbances. Average thickness of the beds ranges from 20 to 1,500m. 2. These carbonaceous slate beds were folded by a strong $F_1$-fold and were refolded by subsequent $F_1$-fold, nearly co-axial with the $F_1$, resulting in a repeated occurrence of similar slate. The carbonaceous beds were swelled in hing zones and were shrinked or thined out in limb by the these foldings. Minor faulting and brecciation of the carbonaceous beds were followed causing metamorphism of these beds and secondary migration and alteration of uranium minerals and their close associations. 3. Uranium-rich zones with high radioactive anomalies are found in Chungju, Deogpyong-Yongyuri, MiwonBoun, Daejeon-Geumsan areas in the range of 500~3,700 cps (corresponds to 0.017~0.087%U). These zones continue along strike of the beds for several tens to a few hundred meters but also discontinue with swelling and pinches at places that should be analogously developed toward underground in their vertical extentions. The drilling surveyings in those area, more than 120 holes, indicate that the depth-frequency to uranium rich bed ranging 40~160 meter is greater. 4. The features that higher radioactive anomalies occur particularly from the carbonaceous beds among the argillaceous lithologic units, are well demonstrated on the cross sections of the lithology and radioactive values of the major uranium deposits in the Ogcheon zone. However, one anomalous radioactive zone is found in a l:ornfels bed in Samgoe, near Daejeon city. This is interpreted as a thermal metamorphic effect by which original uranium contents in the underlying black slate were migrated into the hornfels bed. 5. Principal minerals of the uranium-bearing black slates are quartz, sericite, biotite and chlorite, and as to chemical composition of the black slates, $Al_2O_3$ contents appear to be much lower than the average values by its clarke suggesting that the Changri basin has rather proximal to its source area. 6. The uranium-bearing carbonaceous beds contain minor amounts of phosphorite minerals, pyrite, pyrrhotite and other sulfides but not contain iron oxides. Vanadium. Molybdenum, Barium, Nickel, Zirconium, Lead, Cromium and fixed Carbon, and some other heavy metals appear to be positive by correlative with uranium in their concentrations, suggesting a possibility of their genetic relationships. The estimated pH and Eh of the slate suggests an euxenic marine to organic-rich saline water environment during uranium was deposited in the middle part of Ogcheon zone. 7. The Carboniferous shale of Jangseong Series(Sadong Series) of Permian in Hambaegsan area having low radioactivity and in fluvial to beach deposits is entirely different in geochemical property and depositional environment from the middle part of Ogcheon zone, so-called "Pibanryong-Type Ogcheon Zone". 8. Synthesizing various data obtained by several aspects of research on uranium mineralization in the studied sequence, it is concluded that the processes of uranium deposition were incorporated with rich organic precipitation by which soluble uranyl ions, $U{_2}^{+{+}}$ were organochemically complexed and carried down to the pre-Ogcheon sea bottoms formed in transitional environment, from Red Sea type basin to Black Sea type basin. Decomposition of the organic matter under reducing conditions to hydrogen sulfide, which reduced the $UO{_2}^{+2}$ ions to the insoluble uranium dioxide($UO_2$), on the other side the heavy metals are precipitated as sulfides. 9. The EPMA study on the identification of uraninite and others and the genetic interpretation of uranium bearing slates by isotopic values of this work are given separately by Yun, S. in 1984.

• Korean Journal of Heritage: History & Science
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• v.45 no.2
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• pp.72-99
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• 2012

Cheomseongdae, Korea's so-called "star-gazing tower" located in the former Silla Dynasty capital of Gyeongju, is generally believed to have maintained its original shape since its construction in 647. The stone structure was closely examined and measured by Gyeongju National Museum in 1962 and reexamined by Korean National Research Institute of Cultural Heritage in 2009. This research noted the following structural anomalies of Cheomseongdae. A corner of the top rectangle layer was broken diagonally in a form that can never be attributed to a natural cause. The four metal clamps under the top rectangle layer had been missing. Four grooves, with unknown usage, exist on the sides of the long rectangular stones projected out of the circular body at the second and third circular layers from the top. On the second circular layer from the top, there are three flat stones, less than a half as tall as their surrounding stones. The average height of the third circular layer from the top is only 23.5 cm, while the overall average of the entire 27 circular layers is 29.9cm. This research postulates that all these anomalies are due to prior destructions and improper restorations of the structure. The first destruction and restoration of Cheomsengdae was likely to have occurred before the mid 15th century. The damages might include a pavilion on the top of the structure and a stone with the name of the structure carved in. The Mongolian invasion in the 13th century was a most likely cause. After the restoration, the structure suffered at least another attack. The damages on the top layer and the missing iron clamps were due to the later attack. The grooves and flat stones were to house holding device that affixed certain objects to the outer surface of the circular body. The metal or stone objects might have faced upward at the four corners of Chemseongdae, bridging the gaps between the rectangle layers and circular layers. The current Chemseongdae lost at least the four affixed objects, four holding devices, and one flat stone.

• Economic and Environmental Geology
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• v.22 no.2
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• pp.91-102
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• 1989

The gravity measurement has been conducted at 61 stations with an interval of about 500 to 1,000 m along two survey lines of about 47 Km between $Chungju-Jech{\check{o}}n$ and $Salmi-D{\check{o}}cksanmy{\check{o}}n$ in order to study on the subsurface geologic structure and structural relation between $Okch{\check{o}}n$ Group and Great Limestone Group of $Chos{\check{o}}n$ Supergroup. The Bouger gravity anomalies were obtained from the reduction of the field observations, and the distribution patterns of the basement and subsurface geologic structure were interpreted by means of the Fourier-Series and Talwani method for two-dimensional body. The depth of Conrad discontinuity varies from 12.7 Km to 15.7 Km, and vertical displacements along the Osanri and Bonghwajae faults are 1.0 Km and 1.5 Km, respectively between Chungju and $Jech{\check{o}}n$. The depth of Conrad discontinuity varies from 13.8 Km to 15.4 Km, and vertical displacement along the Bonghwajae fault is 0.5 Km between Salmi and $D{\check{o}}cksanmyon$. The basement is widely exposed at several places between Chungju and $Jech{\check{o}}n$. In the unexposed area between Osanri and $W{\check{o}}lgulri$, its depth is from 1.5 Km to 2.1 Km. It is displaced downward along the Osanri and Bonghwajae faults by 0.8 Km and 0.6 Km, respectively, and is displaced upward along the Dangdusan fault by 1.6 Km. On the other hand, the depth of the basement varies abruptly by the Sindangri, Jungwon, Kounri, and Bonghwajae faults between Salmi and $D{\check{o}}cksanmy{\check{o}}n$, and it is from 2.8 Km to 3.2 Km around $Salmimy{\check{o}}n$, from 1.6 Km to 2.5 Km between the Sindangri and Bonghwajae faults, 3.0 Km near Koburangjae, and 2.5 Km at $Doj{\check{o}}nri$. The high Bouguer gravity anomalies are due to the accumulation of $Okch{\check{o}}n$ Group and $Jangs{\check{o}}nri$ Metamorphic Complex whose density is higher than the basement exposed between Sondong and Osanri, and imply the existance of Bonghwajae Metabasite or hornblende gabbro of high density distributed along the Bonghwajae fault in the vicinity of Koburangjae. The low Bouguer gravity anomalies resulted form the fracture zone associated with fault or rock of low density imply the existance of the Osanri, Bonghwajae, Dangdusan faults and $Daed{\check{o}}cksan$ thrust between Chungju and $Jech{\check{o}}n$, the uplift of the basement by the Sindangri, Jungwon, Kounri, and Bonghwajae faults, and extensive distribution of Cretaceous biotite granites between Salmi and $Docksanmy{\check{o}}n$. The thickness of $Okch{\check{o}}n$ metasediments varies from 1.5 Km to 3.2 Km, and that of Great Limestone Group of $Chos{\check{o}}n$ Supergroup from 200 m to 700 m. It is interpreted that $Okch{\check{o}}n$ Group is in contact with Great Limestone Group of $Chos{\check{o}}n$ Supergroup by the fault zones of the Bonghwajae and $Daed{\check{o}}cksan$ faults, and the Bongwhajae fault is a thrust of high angle, by which the east of the basement is displaced downward 0.5 Km between Chungju and lechon, and 1.0 Km between Salmi and $D{\check{o}}cksanmy{\check{o}}n$.

• Clinical and Experimental Pediatrics
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• v.52 no.6
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• pp.655-660
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• 2009

Purpose : To compare birth weight between infants with a single umbilical artery (SUA) and normal infants, investigate the associated anomalies of infants with SUA and isolated SUA (no abnormality of external appearance on birth, except SUA), and determine the prognosis of infants with isolated SUA. Methods : Live-born infants with SUA (n=59) detected by physical examination from among 15,193 live births in seven university hospitals in Korea between January 1, 2004, to August 1, 2007, were reviewed retrospectively, with 236 normal infants serving as the control group. Results : A statistical difference was observed between the groups in birth weight and in vitro fertilization. The incidence of infants with SUA was 0.37%. Congenital malformations were observed in 21 infants with cardiovascular (n=15, 25.4%), gastrointestinal (n=2, 3.4%), genitourinary (n=9, 15.3%), neuromusculoskeletal (n=6, 10.2%), central nervous system (n=1, 1.7%), chromosomal (n=1, 1.7%), and other (n=3, 5.1%) abnormalities. There were 49 (83.1%) infants with isolated SUA in this study population; among them, the associated congenital malformations were cardiovascular (n=6, 12.2%) and genitourinary (n=6, 12.2%) abnormalities. Two infants with cyanotic heart disease were operated and four infants with acyanotic heart disease showed improvements without any treatment. Six infants with genitourinary abnormalities on renal ultrasound had mild hydronephrosis without further consequences. Conclusion : The incidence of structural abnormalities in the cardiovascular and genitourinary systems is high and the genitourinary anomalies associated with isolated SUA have relatively good prognosis.

• Korea journal of population studies
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• v.15 no.2
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• pp.15-59
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• 1992

After world war II Japanese life expectancy has been improved remarkably, and reached the highest level in the world around late 1970's. The life expectancy of Korean has also shown tremendous improvement in recent years with about 20 year's gap from the Japanese. The reason of rapid improvement of life expectancy can be explained by changes in the structure of cause of death due to health system, living standard, social welfare, health behavior of individuals and so on. Korean in Japan is placed under different situations from both Korean in Korea and Japanese in these regards, and expected to show different picture of cause of death pattern. The objective of this study is the comparision of changing patterns of cause of death of three population groups, Korean in Japan, Korean in Korea and Japanese, and to investigate the reasons which effect to the structural difference of mortality cause with special emphasis on health ecological aspects. One of the major limitations of the Korean causes of death statistics is the under-registration which ranges about 10% of the total events, and inaccuracy of the exact cause of death. Some 20% of registered deaths were unable to classify by ICD. However, it is concluded that the Korean data are evaluated as sufficient to stand for over-viewing of trends of cause of death pattern. The evaluation is done by comparing data from registration and field survey over the same population sample. Population data of Korean in Japan differ between two sources of data; census and foreigner's registration. Correction is done by life table method under the assumption that age-specific mortality pattern would accord with that of the Japanese. The crude death rate was lowest among Korean in Japan, 5.7 deaths per 1,000 population in 1965. The crude death rates of Korean in Japan and Japanese are increasing recently influenced by age structure while Korean in Korea still shows decreasing tendency. The adjusted death rate is lowest among Japanese, followed by Korean in Japan, and Korean in Korea. The leading causes of death of Korean in Korea until 1960's was infectious diseases including pneumonia and tuberculosis. The causes of death structure changed gradually to accidents, neoplasm, hypertensive disease, cerebro-vascular disease in order. The main difference in cause of death between Korean and Japanese if high rate of liver diseases and diabetes for both Korean in Japan and Korea. A special feature of cause of death among Korean in Korea is remakably high rate of hypertensive disease, which is assumed to be caused by physicians tendency in choosing diagnostic categories. The low ischemic heart disease and high vasculo-cerebral disease are the distinctive characteristic of the three population groups compared to western countries. Specific causes of death were selected for detailed sex, age and ethnic group comparisons based on their high death rates. Cancer is the cause of death which showed most dramatical increase in all three population groups. In Korea 20.1% of all death were caused by cancer in 1990 compared with 10.5% in 1981. Cancer of the liver is the leading cause of cancer death among Korean in Japan for both sexes, followed by cancer of the lung and cancer of the stomach, while that of Korean in Korea is cancer of the stomach, followed by cancer of the liver and cancer of the lung for male. Causes of infant mortality were examined among the three population groups since 1980 on yearly bases. For both Japanese and Korean in Japan, leading cause of death ranks as conditions originating in the perinatal period, congenital anomalies, accidents and other violent causes. Trends since 1980 for these two population groups in the leading cause of infant mortality showed no changes. On the contrary, significant changes in leading cause of death structure in Korea were observed : the ranking of leading cause of death in 1981 were congenital asnomalies, pneumonia bronchitis, infectious disease, heart disease, conditions originating in the perinatal period, accident and other violent causes ; in 1990 the ranking shifted to congenital anomalies, accident, pneumonia bronchities, conditions originating in the perinatal period, infectious disease. The mortality rate by congenital anomalies in Korea continuously grew than any other causes. Larger increase ocurred during the 1990's

• Archives of Plastic Surgery
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• v.35 no.3
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• pp.248-254
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• 2008

Purpose: Human acellular dermal matrix(ADM) is widely used in the treatment of congenital anomalies and soft tissue deficiencies. But it is rapidly degraded in the body and does not provide satisfactory results. There is a need to improve collagen fiber stability through various methods and ultimately regulate the speed of degradation. Methods: The ADMs were added with various cross-linking agents called glutaraldehyde, dimethyl 3,3'-dithiobispropionimidate to produce cross-linked acellular dermal matrices. 1,4-butanediol diglycidyl ether solution was applied with a pH of 4.5 and 9.0, respectively. The stability of cross-linked dermal matrix was observed by measuring the shrinkage temperature and the degradation rates. The cross- and non-cross linked dermis were placed in the rat abdomen and obtained after 8, 12 and 16 weeks. Results: The shrinkage temperature significantly increased and the degradation rate significantly decreased, compared to the control(p<0.05). All of cross-linked dermises were observed grossly in 16 weeks, but most of non-cross linked dermis were absorbed in 8 weeks. Histologically, the control group ADM was found to have been infiltrated with fibroblasts and most of dermal stroma were transformed into the host collagen fibers. However, infiltration of fibroblasts in the experiment was insignificant and the original collagen structure was intact. Conclusion: Collagen cross-linking increases the structural stability and decreases degradation of acellular dermis. Therefore, decrease in body absorption and increase in duration can be expected.

• Journal of the Korean earth science society
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• v.23 no.1
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• pp.87-96
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• 2002

Aeromagnetic and gravity data were analyzed to delineate the subsurface structure of the Yeongdong basin and its related fault movement in the Okcheon fold belt. The aeromagnetic data of the total intensity (KIGAM, 1983) were reduced to the pole and three dimensional inverse modeling, which considers topography of the survey area in the modeling process, were carried out. The apparent susceptibility map obtained by three dimensional magnetic inversion, as well as the observed aeromagnetic anomaly itself, show clearly the gross structural trend of the Yeongdong basin in the direction on between $N30^{\circ}E$ and $N45^{\circ}E$. Gravity survey was carried out along the profile, of which the length is about 18.2 km across the basin. Maximum relative Bouguer anomaly is about 7 mgals. Both forward and inverse modeling were also carried out for gravity analysis. The magnetic and gravity results show that the Yeongdong basin is developed by the force which had created the NE-SW trending the magnetic anomalies. The susceptibility contrast around Yeongdong fault is apparent, and the southeastern boundary of the basin is clearly defined. The basement depth of the basin appears to be about 1.1 km beneath the sea level, and the width of the basin is estimated to be 7 km based on the simultaneous analysis of gravity and magnetic profiles. There exists an unconformity between the sedimentary rocks and the gneiss at the southeastern boundary, which is the Yeongdong fault, and granodiorite is intruded at the northwestern boundary of the basin. Our results of gravity and magnetic data analysis support that the Yeongdong basin is a pull-apart basin formed by the left-stepping sinistral strike-slip fault, which formed the Okcheon fold belt.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5741-5747
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• 2015

Purpose: To understand the epidemiology of different upper gastrointestinal (UGI) tract related abnormalities through endoscopic data analysis. Materials and Methods: A retrospective study of three years from January 2009 to December 2011 was conducted with data from endoscopic surveillance of upper GI tract problems, collected from the Gastroenterology Unit, Osmania General Hospital, Hyderabad. MS excel and Medcalc software (comparison of proportions) were used for data analysis. Results: A total of 10,029 (6,468 in males and 3,561 in females) endoscopies were performed during this three-year period. The male to female ratio was 1.8:1. Overall, ~30% of endoscopies evaluated showed patients with acid peptic disorders, 13.6% with vascular-related abnormalities, 10.6% showed structural abnormalities, followed by 6.3% with malignancies. Burden of malignancies was mostly observed in the older age group (60-69 years). Esophageal cancer cases decreased (p=0.0001) whereas stomach cancers increased over this period (p=0.0345). We also observed an increased incidence of acid peptic disease (APD) (p=0.0036) and gastroesophageal reflux disease (GERD) (p=0.0002) cases during this period. Conclusions: Endoscopic diagnosis is useful for early detection of UGI anomalies and helpful for physicians to manage and treat varied kinds of UGI disorders. Analysis of data revealed changing trends in the incidence of various pathologies of the UGI tract. Functional dyspepsia and GERD definitely reduce the quality of life of the individual. The role of our diverse dietary habits and lifestyle associated with these problems have not yet been established, though there have been reports on the effect of coffee, spicy food, wheat-based diet, screening of UGI pathologies along with collection of complete personal and medical history details, can h elp in correlating the patients' condition with various aspects of lifestyle and diet.

• Economic and Environmental Geology
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• v.32 no.2
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• pp.177-187
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• 1999

Gravity, magnetic and VLF surveys were conducted to investigat the structural stability and hazards associated with the Ubong landfill in Pohang City, which has been built to dump industrial wastes. In 1994, the collapse of a bank happened in the 6th landfill site due to sudden heavy rain, and a large quantity of waste materials flowed out to the nearby landfill sites, factories and roads. We used $10{\times}10m$ resolution DEM data for gravity reductions. The maximum variation of the terrain effect in the survey area is about 0.5 mgal and the terrain effect is large in the vicinity of bank boundary. The Bouguer gravity anomaly map shows the effect due to the variatino of thickness and type of waste materials. The small negative gravity anomaly increases from the 9th site to the 6th site. The small negative gravity anomaly of the 9th site reflects the relatively shallow dumping depth of average 14.5 m in this site and increased density of waste materials by the repeated stabilization process of soil overlaying. The 6th site is located at the center of the former valley and rainfall and groundwater are expected to flow from south-east to north-west. Therefore, considering the previous accident of mixing waste and bank materials at the north-west boundary of the landfill, there may be some environmental problems of leakage of contaminated water and bank stability. The complex inversion technique using Simulated annealing and Marquardt-Levenberg methods was applied to calculate three-dimensional density distribution from gravity data. In the case of 6th site, it is apparent that the landfill had been dumped in four sectors. However, most part of the 9th site and showed that high magnetic industrial wastes were concentrated in the 6th site. The result of magnetic survey showing low magnetic anomalies along the boundaries of two sites is similar to that of gravity data. The VLF data also reveals four divided sectors in the 6th site, and overall anomaly trend indicates the directio of former valley.