• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.25-31
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• 2005

Purpose: This study was designed to know the usefulness of the MRI to distinguish lipoma and well differentiated liposarcoma (WDL). Materials and methods: 47 lipomatous tumors with MRI were reviewed among the 107 lipomatous tumors operated in our department. MRI examinations and their corresponding pathology reports were compared to determine sensitivity, specificity, diagnostic ability, positive predictable value and negative predictable value. Statistical analysis was performed to know the relationship between malignancy of the tumor (WDL) with the age and gender of the patients, and location, depth, size and the enhancement of tumors in MRI. Results: Among 28 lipoma in MRI examinations, 26 were proved as lipoma in pathology, and only 6 were WDL from 19 suspicious lesions in MRI, and others were proved as lipoma variants mostly. The varieties of lipoma variants were fibrolipoma, angiolipoma, spindle cell lipoma, lipoblastoma and angiomyolipoma. The sensitivity, specificity, diagnostic ability, positive predictable value and negative predictable value of MRI were 100%, 68 %, 72%, 31% and 100% in WDL, and 90%, 89%, 89%, 93% and 84% in lipoma. Among the variants to distinguish WDL and lipoma, the size of tumor and enhancement in MRI were significant statistically (p<0.05). Conclusion: MRI was highly sensitive in detection of WDL and highly specific in detection of simple lipoma. The size of tumor and enhancement in MRI were significant variants to distinguish WDL and lipoma. When MRI finding is non-specific, it is more likely to represent one of lipoma variants.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.268-277
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• 2008

Authors evaluated 1171 patients at the department of Pediatric Dentistry in Kyoungpook National University Hospital through clinical records and radiographs. And the following features were studied ; age, sex distribution, number of mesiodens per patients, cause of discovery of mesiodens, location, status of eruption, shape and orientation of crown, complication, dental age of adjacent upper incisor tooth at the time of surgical extraction of mesiodens and the relationship between the resolution rate of complication after extraction of mesiodens and the dental age of adjacent upper incisor tooth, length of diastema, the eruption status of lateral incisor and the crowding status of premaxilla. The followings are the results : 1. The cause of discovery of mesiodens were as follows ; delayed eruption of the permanent incisors in 13.8%, midline diastema in 11.6%, radiographs taken for other reasons in 23.4% and for caries treatment in 15.1%. 2. Complication due to the presence of mesiodens did not occur in 36.8%, delayed eruption of adjacent teeth was observed in 16.1%, midline diastema in 34.4%, rotation in 8.8%, displacement in 2.4%, and crowding in 1.0% of all evaluated patients. 3. As for the dental age of adjacent upper incisor tooth at the time of surgical extraction of mesiodens, below 1/3 of total root length were observed in 3.5%, $1/3{\sim}1/2$ of total root length in 19.9%, $1/2{\sim}2/3$ of total root length in 54.7% and over 2/3 in 21.9% of all evaluated patients. 4. Resolution rate of delayed eruption after the extraction of mesiodens was significant higher in the group with the root length below 1/2. Resolution rate of midline diastema was significant higher in the group with diastema width below 3mm and with non-crowding of adjacent upper incisor teeth.

• Journal of Intelligence and Information Systems
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• v.17 no.2
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• pp.61-75
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• 2011

A Geographic Information System(GIS) is a system that captures, stores, analyzes, manages and presents data with reference to geographic location data. In the later 1990s and earlier 2000s it was limitedly used in government sectors such as public utility management, urban planning, landscape architecture, and environmental contamination control. However, a growing number of open-source packages running on a range of operating systems enabled many private enterprises to explore the concept of viewing GIS-based sales and customer data over their own computer monitors. K telecommunication company has dominated the Korean telecommunication market by providing diverse services, such as high-speed internet, PSTN(Public Switched Telephone Network), VOLP (Voice Over Internet Protocol), and IPTV(Internet Protocol Television). Even though the telecommunication market in Korea is huge, the competition between major services providers is growing more fierce than ever before. Service providers struggled to acquire as many new customers as possible, attempted to cross sell more products to their regular customers, and made more efforts on retaining the best customers by offering unprecedented benefits. Most service providers including K telecommunication company tried to adopt the concept of customer relationship management(CRM), and analyze customer's demographic and transactional data statistically in order to understand their customer's behavior. However, managing customer information has still remained at the basic level, and the quality and the quantity of customer data were not enough not only to understand the customers but also to design a strategy for marketing and sales. For example, the currently used 3,074 legal regional divisions, which are originally defined by the government, were too broad to calculate sub-regional customer's service subscription and cancellation ratio. Additional external data such as house size, house price, and household demographics are also needed to measure sales potential. Furthermore, making tables and reports were time consuming and they were insufficient to make a clear judgment about the market situation. In 2009, this company needed a dramatic shift in the way marketing and sales activities, and finally developed a dedicated GIS_based market analysis and sales management system. This system made huge improvement in the efficiency with which the company was able to manage and organize all customer and sales related information, and access to those information easily and visually. After the GIS information system was developed, and applied to marketing and sales activities at the corporate level, the company was reported to increase sales and market share substantially. This was due to the fact that by analyzing past market and sales initiatives, creating sales potential, and targeting key markets, the system could make suggestions and enable the company to focus its resources on the demographics most likely to respond to the promotion. This paper reviews subjective and unclear marketing and sales activities that K telecommunication company operated, and introduces the whole process of developing the GIS information system. The process consists of the following 5 modules : (1) Customer profile cleansing and standardization, (2) Internal/External DB enrichment, (3) Segmentation of 3,074 legal regions into 46,590 sub_regions called blocks, (4) GIS data mart design, and (5) GIS system construction. The objective of this case study is to emphasize the need of GIS system and how it works in the private enterprises by reviewing the development process of the K company's market analysis and sales management system. We hope that this paper suggest valuable guideline to companies that consider introducing or constructing a GIS information system.

• Investigative Magnetic Resonance Imaging
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• v.18 no.4
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• pp.332-340
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• 2014

Purpose : A relative increase in deoxyhemoglobin levels in hypoperfused tissue can cause prominent hypointense signals in the draining veins (PHSV) within areas of impaired perfusion in susceptibility-weighted imaging (SWI). The purpose of this study is to evaluate the usefulness of SWI in patients with acute cerebral infarction by evaluating PHSV within areas of impaired perfusion and to investigate the usefulness of PHSV in predicting prognosis of cerebral infarction. Materials and Methods: In 18 patients with acute cerebral infarction who underwent brain MRI with diffusion-weighted imaging and SWI and follow-up brain MRI or CT, we reviewed the presence and location of the PHSV within and adjacent to areas of cerebral infarction qualitatively and measured the signal intensity difference ratio of PHSVs to contralateral normal appearing cortical veins quantitatively on SWI. The relationship between the presence of the PHSV and the change in the extent of infarction in follow-up images was analyzed. Results: Of the 18 patients, 10 patients showed progression of the infarction, and 8 patients showed little change on follow- up imaging. On SWI, of the 10 patients with progression 9 patients showed peripheral PHSV and the newly developed infarctions corresponded well to area with peripheral PHSV on initial SWI. Only one patient without peripheral PHSV showed progression of the infarct. The patients with infarction progression revealed significantly higher presence of peripheral PHSV (p=0.0001) and higher mean signal intensity difference ratio (p=0.006) comparing to the patients with little change. Conclusion: SWI can demonstrate a peripheral PHSV as a marker of penumbra and with this finding we can predict the prognosis of acute infarction. The signal intensity difference of PHSV to brain tissue on SWI can be used in predicting prognosis of acute cerebral infarction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.286-295
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• 2012

This study was carried out to assess the variation of saponin contents in 293 Korean native soybean landraces reintroduced from USA to Korea in 2007. Group A saponin content ranged from 149.8 ${\mu}g\;g^{-1}$ to 1279.0 ${\mu}g\;g^{-1}$ with an average of 484.9 ${\mu}g\;g^{-1}$. Group B saponin content ranged from 2160.1 ${\mu}g\;g^{-1}$ to 7868.6 ${\mu}g\;g^{-1}$ with an average of 3670.0 ${\mu}g\;g^{-1}$. Total saponin content including both group A and B contents ranged from 2502.8 to 8764.0 ${\mu}g\;g^{-1}$ with an average of 4154.9 ${\mu}g\;g^{-1}$. Five promising landraces for use as breeding materials that showed higher than any other landraces in group B and total saponin content were IT226841, IT226761, IT226841, IT226828 and IT228534. IT226841 showed the highest saponin content with group B content of 7868.5 ${\mu}g\;g^{-1}$ and total saponin content of 8764.0 ${\mu}g\;g^{-1}$ among landraces. In the relationship among each components, group A saponin content showed a positive correlation with group B saponin content (r=0.3708) and total saponin content (r=0.5119). Group B saponin content showed a very high positive correlation (r=0.9876) with total saponin content. When landraces were compared for the total saponin content based on collected location, landraces from North Korea showed the highest, Gyeonggi-do showed second highest content, followed by Chungcheongbuk-do, Gangwon-do, Gyongsangbuk-do, Chungcheongnam-do, Gyongsangnam-do, Jeollabuk-do and Jeollanam-do. Landraces were also grouped according to seed size and seed coat color. Small seed group was higher than medium and large seed groups that showed no significant difference in total saponin content. Seed coat colors showed no significant difference in total saponin content.

• Journal of Animal Science and Technology
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• v.50 no.4
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• pp.519-526
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• 2008

Although beef provides high quality proteins as well as vitamins and minerals, its concentrations of saturated fatty acids and cholesterol give negative impression to some consumers on the other hand. Excess fat, especially cholesterol contents in beef is related with metabolic diseases such as atherosclerosis and hypertension. Unfortunately, the data for the relationship of marbling degree and cholesterol contents in Hanwoo beef is very limited. The objectives of the current study were to provide basic data about cholesterol contents in Hanwoo beef and to compare those among beef cattle breeds using 61 Hanwoo and 15 each of Angus and Wagyu crossbred steers. Samples were collected from M. longissimus area and cholesterol concentrations and fatty acid compositions were analyzed using gas chromatography. Cholesterol concentrations in Hanwoo beef ranged from 32.36 mg/100g to 75.42mg/100g depending on individuals. In Angus, cholesterol contents in lowest marbling degree of “Practically devoid” was 56.84mg/100g, whereas it was 72.85mg/100g in the highest marbling degree of “Abundant” showing increase in cholesterol concentrations as the marbling degree increases. For Wagyu crossbred steers, it was 69.23mg/100g and 78.93 mg/100g for marbling degree of “Practically devoid” and “Abundant”, respectively, showing similar cholesterol concentrations to Angus steers but still much higher than Hanwoo steers. The ratio of unsaturated fatty acids:saturated fatty acids for Hanwoo, Angus and Wagyu Crossbred were 1,48, 1.08 and 1.17, respectively. And the ratio of monounsaturated fatty acids : saturated fatty acids were 1.41, 1.03, and 1.10, respectively showing significantly higher ratios in Hanwoo steers. In conclusion, cholesterol contents and saturated fatty acids in M. longissimus of Hanwoo steers were significantly lower while unsaturated fatty acids were higher comparing to those in Angus or Wagyu Crossbred steers. Further studies, however, considering genetic backgrounds, feeding conditions, slaughtering age, number of samples and location of sampling of experimental animals are necessary.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.4
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• pp.251-261
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• 2003

To measure the GPS position accuracy and its distribution according to the length of the baseline, 30 minutes to 24 hours observations at the fixed location were conducted with two GPS receivers (Ll, 12 channels) on May 29 to June 2, 2002. The GPS data received at the reference station, the rover station and the ordinary times GPS observation station operated by the National Geography Institute in Korea were processed in kinematic and static post-processing methods with a post -processing software. The results obtained are summarized as follows: 1. The number of the satellite that could be observed continuously more than six hours was 16 and most of these satellites were positioned at east-west direction on May 31, 2002. The number of the satellite observed and the geometric dilution of precision (GDOP) determined by the average of every 10 minute for the day were 8 and 3.89, respectively. 2. Both the average GPS positions before and after post-processing were shifted (standalone: 1.17 m, post -processing: 0.43m) to the south and west. The twice distance root mean square (2drms) measured with standalone was 6.65m. The 2drms could be reduced to 33.8% (standard deviation 0=17.2) and 5.3% (0=2.2) of standalone by the kinematic and the static post-processing methods, respectively. 3. The relationship between the length of the baseline x (km) and the 2drms y (m) obtained by the static post-processing method was y=0.00l6x+0.006 $(R^2=0.87)$. In the case of the positioning with the static post-processing method using the GPS receiver, it was found that a positioning within 20cm 2drms was possible when the length of the baseline was less than 100km and the receiving time of the GPS is more than 30 minutes.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.2
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• pp.127-134
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• 1999

This study was performed to obtain the basic data to present rational silvicultural tending plan. It makes these widely distributed pine-oak mixed stand and each of pure stand in middle province on object of this study and do comparative analysis of light condition about stand parameter and natural regeneration according to each slope(north, west and south) conditions of location in central part of South Korea. Sample plots for pine-oak mixed stand and pine and oak pure stand were established on each of southern, northern and western slopes based upon site and growth conditions of the slope. Sample plot was a circle of 0.05ha with a diameter of 25.24 m. A sample plot has between 30 and 40 tree in it. Total 23 sample plots were established; 9 pure pine stands, 8 pine-oak mixed stands. and 6 pure oak stands across lower, middle, upper parts of slopes. Relative light intensity within a stand was' measured by crown- photo(fish-eye lens; 180$^{\circ}$) system through fish-eye lens and by comparing each plot with the denuded through PAR-sensor. The crown closure ratio of pure pine stand (75%) shows much lower than that of mixed stand (90.9%) and pure oak stand (93%). The relative light intensity within a stand showed an opposite result. The crown closure of mixed stands tended to become gradually low as the slope moves from the north to the south, but the relative light Intensity within the stand tended to rise. By analyzing the relationship between the relative light intensity within a stand and stand parameter, light intensity within a stand tended to decrease as the diameter and N/ha increase. Number of oak seedlings and light intensity within a stand is in a straight-line regression relation. In particular, the number of oak seedlings was the highest in mixed stands on the southern slope. But no single pine seedling was found. The unfavorable conditions of l0cm thick litter layer and low relative light intensity in a stand (ranging between 4% and 8%) is considered to prevent pine seeds from germinating.

• Korean Journal of Health Education and Promotion
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• v.1 no.1
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• pp.21-36
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• 1983

It is assumed that menarche is affected not only by the biological factors such as nutrition and genetic heritage, but also it is affected by other socio-cultural environmental factors including weather, geographic location, education and level of modernization. Also recent trend of menarche in Korea indicates that a lot of discussion are being generated to the need of sex education as a part of formal school education. The purpose of this study is to develop the school health education program by determine the age of menarche, the factors relavant to time of menarche and psycho-mental state of students at the time in menarche and investigate the present state of school health education relate to menarche of adolescents. The total number of 732 girls was drown from first, second and third grades of 4 middle schools in Seoul. For the data collection the survey was conducted during the period from May 1 to May 20, 1982 by using prepared questionair. The major results are summarized as follow; 1. Mean age at menarche and the percent distribution of menarche experienced. It was observed that about 68.7% of sampled students have been experienced menarche at the time interviewed. For the each group, age at menarche is revealed that among the students about 37.8% are experienced menarche for under 12 years old group, 62.1% for 13 year-old group, 80.6％ for 14 year-old group and 95.5% for over 15 years old. In sum it was found that the mean age at menarche was 12.3 years old, ranged from age at 10 as earlist the age at 15 as latest. 2. Variables associated with age at menarche. 1) There was tendency those student who belong to upper class economic status have had menarche earlier than those student who belong to lower class. Therefore, economic status is closely related to age at menarche. 2) In time of mother's education level, it is also found that those students whose mother's education levels from high school and college are experienced menarche earlier than those students whose mother's education levels from primary school and no-education. 3) However, in connection with home discipline, there was no significant relationship between age at menarche and home disciplines which are being treated "Rigid", "Moderated ", "Indifferent". 4) Degree of communication between parents and daughter about sex matters was found to be associated each others in determination of age at menarche. 5) It was found that high association between mother's menarche age and their daughter's menarche age was observed. Mother's age at menarche earlier trend to be shown also as earlier of their daughters. 6) Those students belong to "D & E" of physical substantiality index are trend to be earlier in menarche than those students in the index "A & B". 3. Psycho-mental state at the time of menarche. Out of the total students 68.2% had at least one or more than one of subjective symptoms. Shyness was shown as most higher prevalent symptom and others are fear, emotional instability, unpleasant feeling, depression, radical behavior, inferior complex and satisfaction appeared. Very few cases are appeared be guilty and stealing feeling. 4. The present status of school health education program related to menarche. As to the source of information about menarche, teacher was a main source with average index 5.88 and the other informants were mother & family member, friends, books and magagines, movies, television, and radio. For the problem solving at menarche, mother & family members were subject to discussion with an average index 6.02 as high. The others for discuss and knowledge about menarche were books, magagine, friends, teachers, and self-learning based on own experienced. The time of learning about menarche, it was learned as highest percentage with 43.2% at a 6 grades of primary school, middle school with 34.4%, 5 grade of primary school with 18.2%, and 4 grade of primary school with 4.0% respectively.

• Journal of the Korean Geographical Society
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• v.31 no.4
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• pp.699-715
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• 1996

This paper examines the cross-sectional development of children's conception of place. Previous research by Piaget and Weil, Jahoda, Daggs has questioned how young children develop the ablity to comprehend place. Oral interview and graphic test were made vy the children at the age of 5-14, in order to attain information on their knowledge, understanding and feeling about place. These data were used ti indentify developmental stages through cluster analysis. The results suggest that young children's conception of place develops with an identifiable 4 stages. There is no significant difference in development of conception of place between the 2nd year of kindergarten and the 1st year of elementary school, or the between the 5th, 6th year of elementary school and 1st, 2nd year of middle school. Rather, the 4th year of elementary school is an important and crucial truning point in the development of children's conception of place. It is concluded that children's conception of place develops in line with Piaget's general cognitive developmental theory in which the pre-conceptual stage ends at age 7 and the concrete-operation stage starts at age 11 to 12.