• International Journal of Highway Engineering
• /
• v.1 no.1
• /
• pp.107-119
• /
• 1999

The joints in the jointed concrete pavement provide a control against transverse or longitudinal cracking at slab, which may be caused by temperature or moisture variation during or after hydration. Without control of cracking, random cracks cause more serious distresses and result in structural or functional failure of pavement system. However, joints nay cause distresses due to its inherent weakness in structural integrity. Thus, the evaluation at joint is very important. and the joint-related distresses should be evaluated reasonably for economic rehabilitation. The purpose of this paper was to develop an evaluation system at joints of jointed concrete pavement using finite element analysis program, ILLI-SLAB, and nondestructive testing device. FWD. To develop an evaluation system for JCP, a sensitivity analysis was performed using ILLI-SLAB program with a selected variables which might affect fairly to on the performance of transverse joints. The most significant variables were selected from precise analysis. An evaluation charts were made for jointed concrete pavement by adopting the field FWD data. It was concluded that the variables which most significantly affect to pavement deflections are the modulus of subgrade reaction(K) and the modulus of dowel/concrete interaction(G), and limiting criteria on the performance of joints at JCP are 300pci. 500,000 lb/in. respectively. Using these variables and FWD test, a charts of load transfer ratio versus surface deflection at joints were made in order to evaluate the performance of JCP. Practically, Chungbu highway was evaluated by these evaluation charts and FWD field data for jointed concrete pavement. For Chungbu highway, only one joint showed smaller value than limiting criterion of the modulus of dowel/concrete interaction(G). The rest joints showed larger values than limiting criteria of the modulus of subgrade reaction(K) and the modulus of dowel/concrete interaction(G).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.4 no.3
• /
• pp.215-225
• /
• 1999

To study the vertical variations of major elements, trace elements and rare earth elements(REEs) contents in deep-sea sediments, six cores from Korea Deep-sea Environmental Study area(KODES) were analyzed. Topmost sediment layers of KODES area are divided into two Units; brown-colored and peneliquid Unit I and pale brown-colored and relatively solidified Unit II. Contents of major elements, REEs, Cu, Sr and Rb in each Unit are almost same, while contents of Mn, Ni and Co in Unit I are two or three times higher than those in Unit II. R-mode factor analysis represents that surface sediments are composed of alumino-silicate phase (AI-Ti-K-Mg-Fe-Rb-Ce), apatite phase (Ca-P-Cu-Sr-Trivalent Rare Earth Elements) and Mn-oxide phase(Mn-Ni-Co). Factor scores in silicate and apatite phases in each Unit are nearly same, whereas those in Mn-oxide phase in Unit I is higher than those in Unit II. While NilCu ratio in Unit I is two times higher than that in Unit II. We interprete the geochemical fractionation of Ni and Cu as a result that Ni can be remobilized in oxygen-depleted micro-environment in Units I and II and then easily reprecipitated in Unit I, while most of Cu supplied together with organic material is decomposed mostly in Unit I and sorbed into apatite.

• Journal of Preventive Medicine and Public Health
• /
• v.19 no.1 s.19
• /
• pp.31-44
• /
• 1986

For many years, $NO_2$ has been regarded as one of the elements among indoor air pollutants of urban homes, leading to increased public concerns on this gas. For the purpose of preparing the fundamental data for the evaluation and control of health effect relevant to $NO_2$ levels, authors measured the indoor (kitchen, living room, bed room) and outdoor $NO_2$ levels categorized by the type of house(apartment, detached dwelling) and cooking fuel(L.P.G., briquette) in the winter and summer, and surveyed the variables(kitchen ventilation, family size, parental smoking) may effect the indoor $NO_2$ levels. The level of $NO_2$ was measured by Palmes tube, and this survey was carried out at 110 homes in the Pusan area from October 1984 to September 1985. The obtained results were as follows: 1) The mean indoor and outdoor $NO_2$ level in winter and summer, respectively, was $0.029{\pm}0.012$ ppm and $0.022{\pm}0.012$ ppm in the kitchen, $0.022{\pm}0.009$ ppm and $0.018{\pm}0.010$ ppm in the living room, $0.017{\pm}0.008$ ppm and $0.016{\pm}0.010$ ppm in the bed room, and $0.021{\pm}0.007$ ppm and $0.016{\pm}0.007$ ppm outdoors. 2) In the category of the type of house and cooking fuel, the highest mean indoor and outdoor $NO_2$ level in the winter was in apartments using briquettes, and in the summer. the highest level was in apartments using L.P.G. 3) In the category of the type of house, the mean indoor and outdoor $NO_2$ level in the winter and summer was higher in the apartment group compared to detached dwelling. 4) In the category of the type of cooking fuel, the mean indoor and outdoor $NO_2$ level in the winter was higher in the briquette group, and in the summer, the L.P.G. group was higher. 5) In the category of the kitchen ventilation, family size, parental smoking and asthma attack history of children, there was an insignificant difference in the indoor $NO_2$ levels.

• Clinical and Experimental Pediatrics
• /
• v.48 no.2
• /
• pp.165-173
• /
• 2005

Purpose : We performed the study to evaluate the value of the follow-up echocardiogram performed 6 months to 1 year after the onset of Kawasaki disease(KD), as recommended by American Heart Association(AHA) guidelines, when echocardiograms in the convalescent period were normal. Methods : Patients were selected from 147 cases diagnosed with KD at Pusan Paik hospital from January 2000 to October 2003. A total of 45 KD patients belonged to AHA risk level I and II were performed follow-up echocardiography. The patient's medical records and echocardiogram were reviewed. Additionally, we sought the opinion of pediatric cardiologists on the subject by means of a multiple-choice survey. Results : 37 children were belonged to AHA risk level I and the remaining 8 patients were belonged to risk level II. Of these 45 children, none were noted to have abnormalities on later follow-up echocardiogram. In the results of questionnaire, 37 percent of the participants advocate no follow-up after convalescent period for risk level I, and 33.3 percent favor periodic follow-up with echocardiography for risk level II up to one year. But there were no consensus about the diagnostic criteria of coronary abnormalities and how to follow-up these patients. Conclusion : All children with KD should have an echocardiogram at present and a follow-up study 6 to 8 weeks after the onset of fever. However, additional echocardiographies are not justified if the 6- to 8-week follow-up echocardiogram is normal. We would recommend that the more reasonable diagnostic criteria for coronary abnormalities and the Korean guidelines for long-term cardiovascular management and follow-up of KD need to be established.

• Korean Journal of Weed Science
• /
• v.3 no.2
• /
• pp.174-189
• /
• 1983

Experiments were conducted to evaluate the herbicidal characteristics of pyrazolate [4-(2,4-dichloro benzoyl)-1,3-dimethylpyrazol-5-yl-p-toluene-sulphonate] in greenhouse and lowland rice field. Pyrazolate controlled effectively most of annual weeds and such perennial weeds as Sagittaria pygmaea MIQ., Potamogeton distinctus A. BENN, Sagittaria trifolia L., Cyperus serotinus ROTTB, and Scirpus hotarui OHWI., whereas Eleocharis kuroguwai OHWI. was tolerent to pyrazolate. Although pyrazolate was applied at 2 to 10 days after transplanting, there was no difference in weed control The weeding effect was not influenced by percolation, depth of water and soil type. No difference in crop injury of rice was found with various levels of seedling age, transplanting depth, percolation, depth of water, soil type and time of application. When combined with butachlor, the mixture gave the same effect on rice phytotoxicity and weed control as pyrazolate alone did. Pyrazolate moved 1 to 2cm downward in lowland soil regardless of soil type and percolation. The herbicidal activity of pyrazolate persisted in soil for 60 to 90 days, depending on soil type, percolation and presence of soil microorganism.

• Journal of the Korean association of regional geographers
• /
• v.2 no.2
• /
• pp.49-73
• /
• 1996

This study produces quantitatively weather entropy and information ratio using information theory about frequency in the appearance of precipitation phenomenon and monthly change, and then applies them to observation of the change of their space scale by time. As a result of these, this study defines Pusan, Chongju and Kwangju's weather representativeness and then establishes the range of weather representativeness. Based on weather entropy (statistical parameter)-the amount of average weather information-and information ratio, we can define each area's weather representativeness, which can show us more constant form included topographical, geographical factors and season change. The data used for this study are the daily precipitotion and cloudiness during the recent five years($1990{\sim}1994$) at the 69 stations in Korea. It is divided into class of no precipitation, that of precipitation. The results of this study can be summarized as follows: (1) The four season's mean value of information ratio is the highest value. as 0.641, on the basis of Chongju. It is the lowest as 0.572, on the basis of Pusan. On a seasonal basis, the highest mean value of information rate is April's (spring) in Chongju, and the lowest is October's(fall) in Pusan. Accordingly weather representativeness has the highest in Chongju and the lowest in Pusan. (2) To synthesize information ratio of decaying tendancy and half-decay distance, Chonju's weather representativeness has the highest in April, July and October. And kwangju has the highest value in January and the lowest in April and July. Pusan's weather representativeness is not high, that of Pusan's October is the lowest in the year. (3) If we establish the weather representative character on the basis of Chongju-Pusan, the domain of Chongju area is larger than that of Pusan area in October, July and April in order. But Pusan's is larger than Chongju's in January. In the case of Chongju and Kwangju, the domain of Chongju area is larger than that of Kwangju in October, July and April in order, but it is less than that of Kwangju area in January. In the case of Kwangju-Pusan, the domain of Kwangju is larger than that of Pusan in October, July in order. But in April it is less than Pusan's.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.14 no.3
• /
• pp.132-141
• /
• 2012

Climate change impact assessment of cereal crop production in South Korea was performed using land attributes and daily weather data at a farm scale as inputs to crop models. Farmlands in South Korea were grouped into 68 crop-simulation zone units (CZU) based on major mountains and rivers as well as existing land use information. Daily weather data at a 1-km grid spacing under the A1B- and RCP8.5 scenarios were generated stochastically to obtain decadal mean of daily data. These data were registered to the farmland grid cells and spatially averaged to represent climate conditions in each CZU. Monthly climate data for each decade in 2001~2100 were transformed to 30 sets of daily weather data for each CZU by using a stochastic weather generator. Soil data and crop management information for 68 CZU were used as inputs to the CERES-rice, CERE-barley and CROPGRO-soybean models calibrated to represent the genetic features of major domestic cultivars in South Korea. Results from the models suggested that the heading or flowering of rice, winter barley and soybean could be accelerated in the future. The grain-fill period of winter barley could be extended, resulting in much higher yield of winter barley in most CZUs than that of rice. Among the three major cereal grain crops in Korea, rice seems most vulnerable to negative impact of climate change, while little impact of climate change is expected on soybeans. Because a positive effect of climate change is projected for winter barley, policy in agricultural production should pay more attention to facilitate winter barley production as an adaptation strategy for the national food security.

• Journal of the Korean earth science society
• /
• v.38 no.1
• /
• pp.64-79
• /
• 2017

We have reported the petrographic properties on the soda straw primarily based on the field measurements and discussed the causes of their traits. 156 soda straws in district B of the Baeg-nyong Cave nominated with the natural monument No. 260 have been investigated to estimate physical, sedimentological and textural characteristics. The soda straws have an average length of 3.05 cm with a standard deviation of 1.7 cm and a mean diameter of 6.0 mm. This result shows that the average diameter of the soda straws measured in this study is thicker than previous reports by 20%. Although the drip rates of cave water from 85.3% of all the soda straws are exceedingly lower than 1 drop per 10 minutes, almost all soda straws have a dripping water. We firstly report growth lamina in the Korean soda straw from 85.3% of all samples, and this textural dominance indicates that the growth lamina are one of the common features of the soda straws at least in the study area. Secondary precipitations inside the soda straw were identified from 68.6%. Notably, the strong inverse correlation between growth lamina and secondary precipitates was represented from 70.5% of all samples. This finding might be explained by the seasonality of cave drip water supplied into the soda straws or the increased opacity caused by secondary precipitates. Based on petrograhic characteristics, the soda straws in the study area can be classified into normal and erratic types. Hopefully our results on the soda straws in Baeg-nyong Cave would provide a basis for the descriptions of soda straws from other caves and paleoclimatic applications.

• 대한공업교육학회지
• /
• v.41 no.2
• /
• pp.48-68
• /
• 2016

This study was conducted to identify the NCS-related research trends, Keywords, the Keywords Networks and the extension of the Keywords using the sementic network analysis and to seek for the development plans about NCS. For this, the study searched 345 the papers, with the National Competency Standards or NCS as a key word, among master's theses, dissertations and scholarly journals that RISS provides, and selected a total of 345 papers. Annual frequency analysis of the selected papers was carried out, and Semantic Network Analysis was carried out for 68 key words which can be seen as key terms of the terms shown by the subject. The method of analysis were KrKwic software, UCINET6.0 and NetDraw. The study results were as follows: First, NCS-related research increased gradually after starting in 2002, and has been accomplishing a significant growth since 2014. Second, as a result of analysis of keyword network, 'NCS, development, curriculum, analysis, application, job, university, education,' etc. appeared as priority key words. Third, as a result of sub-cluster analysis of NCS-related research, it was classified into four clusters, which could be seen as a research related to a specific strategy for realization of NCS's purpose, an exploratory research on improvement in core competency and exploration of college students' possibility related to employment using NCS, an operational research for junior college-centered curriculum and reorganization of the specialized subject, and an analysis of demand and perception of a high school-level vocational education curriculum. Fourth, the connection forming process among key words of domestic study results about NCS was expanding in the form of 'job${\rightarrow}$job ability${\rightarrow}$NCS${\rightarrow}$education${\rightarrow}$process, curriculum${\rightarrow}$development, university${\rightarrow}$analysis, utilization${\rightarrow}$qualification, application, improvement${\rightarrow}$plan, operation, industry${\rightarrow}$design${\rightarrow}$evaluation.'

• Journal of the Korean Institute of Landscape Architecture
• /
• v.43 no.2
• /
• pp.1-12
• /
• 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.