• The Journal of Engineering Geology
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• 제24권1호
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• pp.111-122
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• 2014

For accurate laboratory evaluations of soil deposits, it is essential that the samples are undisturbed. An artificial ground-freezing system is the one of the most effective methods for obtaining undisturbed samples from sand deposits. The objective of this study is to estimate the shear strengths and the characteristics of elastic waves of frozen-thawed and unfrozen specimens through the undrained triaxial compression test. For the experiments, Jumunjin standard sands are used to prepare frozen and unfrozen specimens with similar relative densities (60% and 80%). The water pluviation method is used to simulate the fully saturated condition under the groundwater table. When thawing the frozen specimens, the temperature is measured every minute. After the specimens are completely thawed, undrained triaxial compression tests are conducted using the same procedures as for the unfrozen specimens. During the triaxial tests (saturation, consolidation, and shear phase), compressional and shear waves are measured. The results show that the freeze-thaw process has minor effects on the peak deviatoric stress and shear strength values, and that the process does not affect the internal friction angle. The compressional wave velocity increases with increasing B-value to 1800 m/s in the saturation phase, but tends to remain constant in the process of consolidation and shearing. The shear wave velocity decreases with increasing B-value in the process of saturation, but changes velocity in accordance with the change in effective stress in the processes of consolidation and shearing. The compressional wave velocity has similar values regardless of the freeze-thaw process, but values of shear wave velocity are slighly lower in frozen-thawed specimens than in unfrozen specimens. This study is a preliminary experiment for estimating the shear strength and characteristics of elastic wave velocity in undisturbed frozen specimens that have been obtained using the artificial ground-freezing method.

• Journal of the Korean Institute of Landscape Architecture
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• 제43권2호
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• pp.1-12
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• 2015

This study explores urban gardening and garden culture in residential area as an everydayness that has been overlooked during the modern period urbanization and investigates the meaning and value of urban gardening from the perspective of urban formations and growth in spontaneous urban residential area, Haebangchon. The result identified that urban gardening as a meaning of contemporary culture is a new clue to improving the urban physical environment and changing the lives and community network of residents. Haebangchon is one of the few remaining spontaneous habitations in Seoul, and was created as a temporary unlicensed shantytown in 1940s. It became the representative habitation for common people in downtown Seoul through the revitalization of the 60s and the local reform through self-sustaining redevelopment projects during the 70s through the 90s. This area still contains the image of times during the 50s to the 60s, the 70s to the 80s and present, with the percentage of long-term stay residents high. Within this context, the site is divided into third quarters, and the research undertaken by observation and investigation to determine characteristics of urban gardening as an everydayness. It can be said that urban gardening and garden culture in Haebangchon is a unique location culture that has accumulated in the crevices of the physical condition and culture of life. These places are an expression of resident's desires that seeking out nature and gardening as revealed in densely-populated areas and the grounds of practical acting and participating in care and cultivation. It forms a unique, indigenous local landscape as an accumulation of everyday life of residents. Urban gardens in detached home has retained the original function of the dwelling and the garden, or 'madang', and takes on the characteristic of public space through the sharing of a public nature as well as semi-private spatial characteristic. Also, urban gardens including small kitchen garden and flowerpots that appear in the narrow streets provide pleasure as a part of nature that blossoms in narrow alley and functions as a public garden for exchanging with neighbors by sharing produce. This paper provides the concept of redefining the relationship between the private-public area that occurs between outside spaces that are cut off in a modern city.

• Korean Journal of Microbiology
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• 제33권4호
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• pp.262-266
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• 1997

Total, direct viable count, and acid-tolerant epiphytic bacterial population sizes were quantified on leaves of chestnut tree (Castanea crenata S. et Z.) near Taejon Industrial Estate affected by acid precipitation and deposition as well as in the clean natural forest area, Mt. Kyejok, in Taejon city from August 1996 to August 1997. Geometric mean numbers of total, direct viable count, and acid-tolerant epiphytic bacteria were $9.9{\times}10^5cell/cm^2$, $1.6{\times}10^6cell/cm^2$, and $7.1{\times}10^3cfu/cm^2$ respectively, being 1.5, 2, and 2.6 times those in the clean area. Acid-tolerant epiphytic bacterial numbers at pH 5.6 by MPN method were $3.3{\times}10^4$ in the industrial area, about the same as the number, $3.4{\times}10^4MPN/cm^2$, of the clean area. Acid-tolerant bacterial number at pH 4.0 was $1.9{\times}10^{-1}MPN/cm^2$ in the industrial area, whereas none was detected in the clean area. Acid-tolerant bacteria at pH 3.0 were not detected at all in the industrial area as well as in the clean area. Epiphytic bacterial population sizes were generally the greatest in May when leaves are emerged and grew hut the lowest in November when defoliation occurs. These results showed that air pollutant deposition on leaves did not cause a decrease of epiphytic bacteria at least and acid deposition on leaves did cause an increase of acid-tolerant bacteria.

• Parasites, Hosts and Diseases
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• 제29권3호
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• pp.293-310
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• 1991

Clonorchis sinensis is a common parasite of man in Korea. Researches on the specific antigens of C. sinensis would be valuable not only because those elucidate the molecular characteristics of this fluke but also because it is applicable to immunodiagnosis. Although many monoclonal antibodies have been used in the field of parasite immunology, few articles on monoclonal antibodies against C. sinensis have been published so far. The aim of this study was to analyse C. sinensis antigens recognized by monoclonal antibodies, and to set up ELISA-inhibition test using C. sinensis specific monoclonal antibodies for improved specificity of immunodiagnostic tests. By fusion between spleen cells of the mice immunized with C. sinensis water-soluble crude adult worm antigens and plasmacytoma cells of mouse origin, 29 hybridoma clones secreting anti-C. sinensis monoclonal antibodies were made, and 8 clones among those were found specific. After cell cloning, isotypes of 6 selected specific monoclonal anti- bodies were determined to be IgGl, IgG2b and IgA. Four exposed antigenic determinants of natural infection were recognized by different specific monoclonal antibodies. By enzyme-immunoelectrotransfer blot, 10 KD, 34 KD antigenic determinants were found to be reacted with CsHyb 0714-20, CsHyb 0605-10 monoclonal antibodies, respectively, The antigenic determinant recognized by CsHyb 0714-20 monoclonal antibody was revealed to be located at the surface and parenchyme of a parasite by indirect immunoauorescent antibody technique, and those reacted with CsHyb 0605-10, CsHyb 0714-25 monoclonal antibodies were found at the parenchyme and intestine. The antigenic determinant reacted with CsHyb 0605-23 monoclonal antibody was found mainly around the uterine eggs. Four antigenic determinants recognized by specific monoclonal antibodies were all found to be present in the early eluted fractions of C. sinensis antigens separated by Sephadex G-200 gel filtration. By conventional ELISA, 75% of clonorchiasis cases were found positive, but 7.1% of normal controls and 37.5% of paragonimiasis cases showed false positives. However, by ELISA-inhibition test using C. sinensis specific monoclonal antibody (CsHyb 0605-23), 77.1% of clonorchiasis cases were found positive, and there were no false positives in normal controls or paragonimiasis cases, indicating 100% specificity. The ELISA- inhibition test using monoclonal antibodies was found to have same sensitivity and definitely high specificity in comparison with conventional ELISA for serodiagnosis of human clonorchiasis.

• Childhood Kidney Diseases
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• 제17권2호
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• pp.101-109
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• 2013

Purpose: Pediatric urolithiasis is uncommon in children but is a cause of significant morbidity and damage to the kidney. Although much information on adult urolithiasis is available in the literature, large studies on the pediatric population are still scarce. In this report, we review our experience with pediatric urolithiasis over 22 years at a tertiary referral center. Method: We retrospectively reviewed the records of children with newly diagnosed urolithiasis between January 1991 and May 2013. We assessed the age, sex, family history, initial symptoms, location of stones, underlying cause, stone analysis, treatment, and recurrence among the patients. Results: In total, 137 patients (96 male, 41 female) were assessed. The age range was 0-17 years (mean age, 6.0 years). Forty-three (31%) children were aged <1 year, and 37% (16/43) had a history of intensive care unit (ICU) admission. Thirteen patients (9.5%) had a family history of stones. The most common symptoms at presentation among the patients were gross hematuria (56/137, 41%) and flank or abdominal pain (46/137, 34%). The stones were located in the kidney (85/137, 62%), ureter (29/137, 21%), bladder (2/137, 1.4%), and multiple locations (20/137, 15 %). Congenital abnormalities of the genitourinary (G-U) tract, with or without metabolic abnormality, or urinary tract infection (UTI) was detected in 26 children (19%). Ninety-one patients (66%) underwent metabolic examination, and 38% of these patients exhibited an abnormality. UTI, with or without abnormalities of the G-U tract, or metabolic abnormality was detected in 26 children (19%). Of the 35 stones analyzed, the majority were calcium stones (20/35, 57%), followed by infected stones (5/35, 14%), uric acid stones (4/35, 11%), carbonate apatite stones (3/35, 7%), cystine stones (2/35, 6%), and phosphate stones (1/35, 3%). Five patients (4%) required open procedures, with or without non-open procedures, whereas 77 patients (56%) were managed conservatively; the remaining 55 patients (40%) received some other form of intervention. Eighteen patients (13%) had stone recurrence during the follow-up period. Conclusions: Pediatric urolithiasis is commonly associated with abnormalities of the G-U tract and/or metabolic disorders and/or UTI. Half of the patients will pass their stones spontaneously, and all the techniques of minimally invasive surgery are applicable in the treatment of children with stones. As the recurrence rates are high among this population, long-term follow-up is recommended and the complete clearance of stones is important.

• Journal of Bio-Environment Control
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• 제13권1호
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• pp.44-50
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• 2004

This experiment was conducted to investigate the effects of different levels of light intensity (100, 200, 400 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$, and natural light) on the growth and the fruit quality of cucumber(Cucumis sativus cv. Hyakunari-3). The results of this experiment indicated that plant height and length of lateral shoots were decreased under low light condition, but it was not significantly different among treatments. Leaf area and root weight were lowest under low light intensity(100 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$), but no significant differences were noted between 200 and 400 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$. Photosynthesis rate was decreased with reduced light intensity and total chlorophyll contents, root activity and xylem sap were also decreased under low light intensity, but there was no significant difference between 200 and 400 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$. From the SEM observation the erosion of the guard cells and closed stomata in low light treatment were shown and the size of stoma were small also the stomatal aperture were decreased with reducing the light intensity. Chlorosis in leaves and aborted-liked fruits were appeared under low light condition and Ca and Mg uptake in leaves were decreased by shading in proportion to the decrease of light intensity. Fruit yields were decreased by 65% under 400 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$, and by 80${\sim}$90% under 200 and 100 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$, compared to those under the natural light. This low intensity of light caused the sharp decrease in the early harvested yields within two weeks and the fruit yields of lateral shoots were greatly decreased.

• Korean Journal of Heritage: History & Science
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• 제51권4호
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• pp.120-145
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• 2018

This study intended to examine the drainage facility of Gyeongbokgung Palace based on the traces of the relic found during the excavation survey. Historical records indicate that various efforts have been made for smooth drainage facility for the palace since the foundation of the Joseon Dynasty. Although there are no drawings showing the image of early appearance of Gyeongbokgung Palace during the foundation, it is possible to estimate it through the drawings prepared after the King Yeongjo's reign. The image of the palace after reconstruction can be seen through the "Bukgwoldohyeong" and other relevant documents. At this present, since the survey intends to determine the image of Gyeongbokgung Palace during the reign of King Gojong based on the standard restoration plan of the Cultural Heritage Administration, this study also focused on the drainage facility of Gyeongbokgung Palace during King Gojong's reign, particularly on the collecting wells and culverts of six areas including "Chimjeon Hall", "Taewonjeon Hall", "Geoncheongung Hall", "Sojubang Hall", "Hamhwadang - Jipgyeongdang - Yeonghundang Hall", and "Heungbokjeon Hall". Gyeongbokgung Palace is divided into various zones composed of the central halls and surrounding corridors, and the drains also primarily start from each hall and later join the central drain of the zone. The central drain then leads to the "Eo-gu(御溝)" and the water led to the "Eo-gu" is finally discharged through the water gate. It appears that this series of processes were basically devised to coordinate artificial drain with the natural drain using the natural geographical features of the palace. Research showed that the collecting well where the draining begin was installed in the area where a large amount of household sewage was generated but mostly in the corners where corridors met or corridors and wall met. This appears to be an arrangement to handle the water falling from the roof and household sewage. Also, "Ju(廚)" was installed mainly at the end of the corridor to handle household sewage. The installation of these drainage facilities shows the possibility that the drainage of Gyeongbokgung was very compact under a series of plans.

• Korean Journal of Heritage: History & Science
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• 제50권3호
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• pp.4-29
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• 2017

The purpose of this study is to grasp the commencement date of Korean-type bronze dagger through the chronology of Chinese data. It focuses on the fact that the same section polishing technique appears both in Korean type bronze dagger and Dongzhou type bronze dagger. Dongzhou type bronze dagger in Anqiu Shandong, in which A1 type section polishing technique is observed, was said to have been collected remains in 1958, but the clear excavation cannot be identified. Therefore, this study presents Tomb No.1 Zuojiawa Jinan, Dongzhou type bronze dagger, and associated products. As associated products, bronze weapon and bronze ware were excavated, whose periods are estimated to be in the Spring and Autumn period, the transition period of Warring States, and the former part of the China's Warring States. Accordingly, the Korean bronze dagger, excavated in the remains of the Han Peninsula appears to have run parallel with the Dongzhou type bronze dagger of the A1 type section polishing technique, excavated in China for a fixed period. In addition, the chronology of Tomb No. 61MI grave in Wanrongmiaoqian, Shanxi is estimated to range from the former part to the middle part of the China's Warring States, which is identified to be connected to the A1 type section polishing technique. Examining the data of the relative date, we can find out that the Commencement Period of the Korean type bronze dagger Culture is seen to be the transition period and the former part of the China's Warring States, which is estimated to be the 5th and 4th centuries BC. This chronology is followed by Tomb No.6512 Zhengjiawazi Shenyang, recorded as the 6th century B.C. which reveals that Liaoning type bronze dagger culture and Korean-typed Bronze Dagger Culture are naturally connected. Furthermore, the A1 type section polishing technique was distributed in the southwestern area of the Korean peninsula and Shandong, China, while the A2 type section polishing technique was distributed in the southern area of the Korean peninsula, Shanxi-Province in China, and Northern Kyushu region in Japan. Seen from the weapon-shaped bronze ware of the section polishing technique, Shanxi area(Central Plains area), China. the southwestern area of the Korean peninsula (northwest area), and Northern Kyushu region in Japan are set up as one traffic road(spreading route). This demonstrates that the section polishing technique emerged around the Han Peninsular, spreading the technique regionally.

• Particle and aerosol research
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• 제15권1호
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• pp.37-44
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• 2019

It is recommended for the public to stay at home and to close the doors and windows when a high-particulate-matter environment such as a yellow sand event occurs outside. However, there are lack of empirical studies describing how much outdoor PM infiltrates into a closed house and how much indoor PM an inhabitant is exposed to during the period. In this study, the $PM_{10}$ and $PM_{2.5}$ were measured at the kitchen in an apartment house by an optical particle counter for 3 days including a yellow sand event. The outdoor PMs and the outdoor wind speeds were referred from surrounding weather stations. We analyzed the penetration of $PM_{10-2.5}$ and $PM_{2.5}$ at the test house against the outdoor wind speed supposed corresponding to the change of air exchange rate. In addition, the effect of an indoor activity on change in the indoor PM was investigated. In result, the indoor $PM_{10-2.5}$ was very low even a yellow sand event occurred outside; rather, a contribution of indoor activities to increase in $PM_{10-2.5}$ was higher. In contrast, the indoor $PM_{2.5}$ fluctuated following the outdoor $PM_{2.5}$ trend at high wind speeds or remained almost constant at low wind speed.

• Ecology and Resilient Infrastructure
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• 제6권1호
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• pp.34-48
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• 2019

Naeseong Stream is a natural sand-bed river that flows through mountainous and cultivated area in northern part of Gyeongbuk province. It had maintained its inherent landscape characterized by white sandbars before 2010s. However, since then changes occurred, which include construction of Yeongju Dam and the extensive vegetation development around 2015. In this study, long-term monitoring was carried out on Naeseong Stream to analyze these changes objectively. This paper aims to provide a dataset of the investigation on channel morphology and vegetation for the period 2012-2018. Methods of investigation include drone/terrestrial photography, LiDAR aerial survey and on-site fieldwork. The main findings are as follows. Vegetation development in the channel of Naeseong Stream began around 1987. Before 2013 it occurred along the downstream reach and since then in the entire reach. Some of the sites where riverbed is covered with vegetation during 2014~2015 were rejuvenated to bare bars due to the floods afterwards, but woody vegetation was established in many sites. Bed changes occurred due to deposition of sediment on the vegetated surfaces. Though Naeseong Stream has maintained its substantial sand-bed characteristics, there has been a slight tendency in bed material coarsening. Riverbed degradation at the thalweg was observed in the surveyed cross sections. Considering all the results together with the hydrological characteristics mentioned in the precedent paper (I), it is thought that the change in vegetation and landscape along Naeseong Stream was mainly due to decrease of flow. The effect of Yeongju Dam on the change of the riverbed degradation was briefly discussed as well.