• Journal of the Korean Geophysical Society
• /
• v.3 no.2
• /
• pp.77-90
• /
• 2000

Five electrical resistivity dipole-dipole and two seismic reflection surveys were performed in the southeastern margin of the Yongdong basin to delineate the shallow basin architecture. To investigate the intra-basin structure, twenty four resistivity sounding points and three dipole-dipole lines were selected especially in the vicinity of volcanic masses. The basin-fault boundaries are identified in electrical dipole-dipole resistivity section as high resistivity-contrast of approximately $1,500\;{\Omega}{\cdot}m$, characterized as a band of high standard-deviation. They are also effectively clarified in the seismic reflection data: amplitude and continuity contrasts in the common shot gather, first-arrival profiles, complex attribute plots. The intra-basin resistivity structures are constructed by interpolating vertical electrical sounding data and dipole-dipole profiles. The high-resistivity anomalies most likely originate from the northsouth-trending and northeast-dipping volcanic masses, which are to be further quantitatively investigated with geomagnetic and magnetotelluric surveys.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.4
• /
• pp.453-468
• /
• 2020

This study was conducted to investigate factors influencing physical activity in female nursing students based on the habit formation model. The participants were 207 female students at G nursing college and J nursing college located in J city. All data were collected from 31, August to 14, September in 2020 and analyzed by descriptive statistics, ANOVA and Scheffĕ test, Pearson's correlation coefficient, Univariate, and Multivariate multinomial logistic regression using SPSS/WIN 22.0 program. The average level of physical activity measured by the Korean version of IPAQ was 2506.31±2807.05 MET-min/week. According to the physical activity category classified by IPAQ, there were 59students(28.5%) in the high group, 98students(47.3%) in the moderate group, and 50students(24.2%) in the low group. Physical activity habit strength was the significant factor influencing physical activity in female nursing students. Therefore, this study suggests that it is necessary to develop the habit formation program and verify effectiveness for enhancing and maintaining the physical activity in female nursing students.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.4
• /
• pp.248-259
• /
• 2017

This descriptive correlational study was conducted to identify the factors influencing the uncertainty of patients undergoing chemotherapy for lung neoplasms. One hundred and eleven patients were recruited from the chemotherapy clinic of a university hospital. Data were collected from July 25 to December 31, 2014, and analyzed by descriptive statistics, the t-test, ANOVA, the Scheffe test, Pearson's product moment correlation coefficients and multiple regression analysis with SPSS for Windows Version 18.0. The mean score of the uncertainty of the patients undergoing chemotherapy for lung neoplasms was 2.61(${\pm}0.46$), which was higher than that of the patients with other diseases. The uncertainty was positively correlated with the seriousness of the illness (r=.74, p<.01) and consistency of the symptoms (r=.27, p<.01). Multiple regression analysis showed that the (main) factor influencing the uncertainty was the seriousness of the illness, which explained 54% of the uncertainty of the patients undergoing chemotherapy for lung neoplasms. As a result, nursing interventions are needed to reduce the uncertainty of lung neoplasm patients who are receiving chemotherapy. The seriousness of the illness should be considered when developing nursing interventions to reduce the uncertainty of lung neoplasm patients.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.2
• /
• pp.539-547
• /
• 2021

This study was conducted to identify the effects of knowledge of Advance Directives (AD) and the patient's perception of a peaceful death on their attitude toward the withdrawal of life-sustaining treatment and to provide basic data for the development of a nursing intervention program for activating self-determination in the withdrawal of life-sustaining support of patients. The subjects were 167 adult cancer patients who received outpatient or inpatient treatment, from September 15, 2019, to March 30, 2020. The data was analyzed by mean, standard deviation, t-test, ANOVA, Pearson's correlation coefficient, and multiple regression by using SPSS 21.0. From the results, it was observed that the knowledge of AD was 8.87±2.46 out of 12, perception of a peaceful death was 2.87±0.42 out of 4, and attitude toward withdrawal of life-sustaining treatment was 3.46±0.49 out of 5. There was a positive correlation between knowledge of AD, perception of a peaceful death, and their attitude toward withdrawal of life-sustaining treatment. The influencing variables were the knowledge of AD, perception of a peaceful death, discussion with family on withdrawal of life-sustaining treatment, and explanation power was 16.0% (F=10.355, p<.001). Therefore, it is necessary to develop a program that would improve the perception of a peaceful death, increase the knowledge of AD to improve the patients' attitude toward the withdrawal of life-sustaining treatment. An intervention to assist a discussion between the patients and their families in advance would also be useful.

• Journal of Korean Society of Spine Surgery
• /
• v.25 no.4
• /
• pp.160-168
• /
• 2018

Study Design: Retrospective study of prospectively-collected data. Objectives: To determine the factors associated with conversion from conservative to surgical treatment in single-level lumbar spinal stenosis patients. Summary of Literature Review: Various reports have presented clinical outcomes after the surgical and nonsurgical treatment of spinal stenosis. However, few reports have investigated factors predicting conversion to surgery during the course of conservative treatment. Materials and Methods: We analyzed 40 patients who visited our hospital from May 2010 to May 2015 and were traceable for at least 3 years after being advised to undergo surgery following 3 months of conservative treatment. Of these patients, 20 underwent surgery and 20 did not. We then investigated the factors associated with conversion to surgical treatment. Clinical assessments were conducted using a questionnaire, and the overall area of the spinal canal and the muscle area within the spinal canal were measured using magnetic resonance imaging. Results: The average area of the spinal canal was $81.40{\pm}53.61mm^2$ in the surgical group, compared to $127.75{\pm}82.55mm^2$ in the nonsurgical group (p=0.042). The muscle area in the spinal canal was $5.17{\pm}1.30cm^2$ in the surgical group, whereas it was $6.40{\pm}1.56cm^2$ in the nonsurgical group (p=0.010). The patients in the surgical group were more likely to have experienced repetitive strain and to have frequently visited health clubs (p=0.047, p=0.037, respectively). However, regular stretching was more common in the nonsurgical group (p=0.028). Conclusions: The factors associated with conversion to surgical treatment were a narrow spinal canal, a small muscle area within the spinal canal, visiting health clubs, repetitive sprain, and not stretching. A small muscle area within the spinal canal can be considered as a key factor related to surgical conversion.

• Journal of Intelligence and Information Systems
• /
• v.27 no.1
• /
• pp.65-82
• /
• 2021

Stock market investors are generally split into foreign investors, institutional investors, and individual investors. Compared to individual investor groups, professional investor groups such as foreign investors have an advantage in information and financial power and, as a result, foreign investors are known to show good investment performance among market participants. The purpose of this study is to propose an investment strategy that combines investor-specific transaction information and machine learning, and to analyze the portfolio investment performance of the proposed model using actual stock price and investor-specific transaction data. The Korea Exchange offers daily information on the volume of purchase and sale of each investor to securities firms. We developed a data collection program in C# programming language using an API provided by Daishin Securities Cybosplus, and collected 151 out of 200 KOSPI stocks with daily opening price, closing price and investor-specific net purchase data from January 2, 2007 to July 31, 2017. The self-organizing map model is an artificial neural network that performs clustering by unsupervised learning and has been introduced by Teuvo Kohonen since 1984. We implement competition among intra-surface artificial neurons, and all connections are non-recursive artificial neural networks that go from bottom to top. It can also be expanded to multiple layers, although many fault layers are commonly used. Linear functions are used by active functions of artificial nerve cells, and learning rules use Instar rules as well as general competitive learning. The core of the backpropagation model is the model that performs classification by supervised learning as an artificial neural network. We grouped and transformed investor-specific transaction volume data to learn backpropagation models through the self-organizing map model of artificial neural networks. As a result of the estimation of verification data through training, the portfolios were rebalanced monthly. For performance analysis, a passive portfolio was designated and the KOSPI 200 and KOSPI index returns for proxies on market returns were also obtained. Performance analysis was conducted using the equally-weighted portfolio return, compound interest rate, annual return, Maximum Draw Down, standard deviation, and Sharpe Ratio. Buy and hold returns of the top 10 market capitalization stocks are designated as a benchmark. Buy and hold strategy is the best strategy under the efficient market hypothesis. The prediction rate of learning data using backpropagation model was significantly high at 96.61%, while the prediction rate of verification data was also relatively high in the results of the 57.1% verification data. The performance evaluation of self-organizing map grouping can be determined as a result of a backpropagation model. This is because if the grouping results of the self-organizing map model had been poor, the learning results of the backpropagation model would have been poor. In this way, the performance assessment of machine learning is judged to be better learned than previous studies. Our portfolio doubled the return on the benchmark and performed better than the market returns on the KOSPI and KOSPI 200 indexes. In contrast to the benchmark, the MDD and standard deviation for portfolio risk indicators also showed better results. The Sharpe Ratio performed higher than benchmarks and stock market indexes. Through this, we presented the direction of portfolio composition program using machine learning and investor-specific transaction information and showed that it can be used to develop programs for real stock investment. The return is the result of monthly portfolio composition and asset rebalancing to the same proportion. Better outcomes are predicted when forming a monthly portfolio if the system is enforced by rebalancing the suggested stocks continuously without selling and re-buying it. Therefore, real transactions appear to be relevant.

• The Korean Journal of Elementary Counseling
• /
• v.10 no.2
• /
• pp.167-184
• /
• 2011

This study has investigated how five peer status groups that were selected by a social skills scale exhibit different peer relationship problems by means of averages, standard deviations, and profile analysis. Social skills scale developed by Yi-Hwan Ahn(2007) and the inventory of peer relationships by Hae-Won Jung(2007) were administered to 551 fifth and sixth graders in 9 elementary schools located in Gyungnam province, and averages and standard deviations of 5 peer status groups' peer relationship problems were explored. Also in order to see if differences exist among 8 sub-scales in the inventory of peer relationships according to the peer status, an average profile of scores was represented by a graph and multivariate analysis was carried out. The main results of the study are as follows. First, statistical analysis of 551 cases included in the study showed the children were distributed into the Average group(319, 57.9%), the Popular group(111, 29.1%), the Rejected group(70, 12.9%), the Controversial group(41, 7.4%), and the Neglected group(10, 1.8%), in that order. Second, as a result of comparing average scores for each measure in the inventory of peer relationships according to the peer status group, a significant difference was found to exist according to a child's peer status. The Popular group showed the lowest scores in Too Controlling, Hard to be Supportive, the Cold, and Non-Assertive among the 5 peer status groups whereas the Rejected group showed the highest scores in Social Avoidant, Non-Assertive, and Too Responsible. Third, marked differences according to the peer status group were found. The Popular group showed the lowest profile among the peer status groups whereas the Rejected group had the highest profile. In the sub-scales of the peer relationship problems, the Rejected children showed a significantly higher level of Socially Avoidant and Non-Assertiveness in comparison to the Popular children, which implies the Popular children group has lower levels of peer relationship problems than the other groups.

• Journal of the Korean Society of Radiology
• /
• v.15 no.7
• /
• pp.991-998
• /
• 2021

The purpose of this study is to investigate the image quality of the SE-EPI and SSH-TSE technique for MR DWI. Datum were analyzed for 35 PACS transmission datum(Normal part: 12 males, 13 females, Cerebral Infarction: 10(5males and 5females), and average age 68±7.32), randomly selected patients who underwent MRDWI tests. The equipment used was Ingenia CX 3.0T, SSH_TSE and SE-EPI pulse sequence and 32 Ch. head coil were used for data acquisition. Image evaluation was performed on the paired t-test and Wilcoxon tests, and was considered significant when the p value was 0.05 or less. As a result of quantitative analysis of SNR for DWI images, the mean and standard deviation values of 4 parts (WM, GM, BG, Cerebellum) in ADC (s/mm2), Diffusion b=0, 1000 images were higher in SE-EPI techniques(ADC: 120.50 ± 40, b=0: 54.50 ± 35.91, b=1000: 91.61 ± 36.63) than in SSH-TSE techniques(ADC: 99.69 ± 31.10, b=0: 43.52 ± 25.00 , b=1000: 60.74 ± 24.85)(p<0.05). The CNR values for GM-WM, BG-WM sites were also higher in SE-EPI technique (ADC: 116.08 ± 43.30, b=0:27.23 ± 09.10, b=1000: 78.50 ± 16.56) than in SSH-TSE(ADC: 101.08 ± 36.81, b=0: 23.96 ± 07.79 , b=1000: 74.30 ± 14.22). As a visual evaluation of observers, ghost artifact, magnetic susceptibility artifacts and overall image quality for SE-TSE and SSH-TSE all yielded high results from SSH-TSE techniques(ADC:3.6 ± 0.1, 2.8 ± 0.2, b=0: 4.3 ± 0.3, 3.4 ± 0.1 b=1000: 4.3 ± 0.2, 3.5 ± 0.2, p=0.000). In conclusion, the SE-EPI technique obtained an superiority in SNR and CNR measurements using SSH-TSE, SE-EPI. In the qualitative analysis, the SSH-TSE pulse sequence was obtained a high result according to the pulse sequence characteristics.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.16 no.3
• /
• pp.13-29
• /
• 2021

The purpose of this study was to analyze the spatial distribution and location factors of startups by generation (young and middle-aged) in Seoul. To this end, a research model was established that included factors of industry, population, and startup institutions by generation in 424 administrative districts using the Seoul Business Enterprise Survey(2018), which includes data on the age group of entrepreneurs. As an analysis method, descriptive statistics were conducted to confirm the frequency, average and standard deviation of startups by generation and major variables in the administrative districts of Seoul, and spatial distribution and characteristics of startups by generation were analyzed through global and local spatial autocorrelation analysis. In particular, the spatial distribution of startups in Seoul was confirmed in-depth by categorizing and analyzing startups by major industries. Afterwards, an appropriate spatial regression analysis model was selected through the Lagrange test, and based on this, the location factors affecting startups by generation were analyzed. The main results derived from the research results are as follows. First, there was a significant difference in the spatial distribution of young and middle-aged startups. The young people started to startups in the belt-shaped area that connects Seocho·Gangnam-Yongsan-Mapo-Gangseo, while middle-aged people were relatively active in the southeastern region represented by Seocho, Gangnam, Songpa, and Gangdong. Second, startups by generation in Seoul showed various spatial distributions according to the type of business. In the knowledge high-tech industries(ICT, professional services) in common, Seocho, Gangnam, Mapo, Guro, and Geumcheon were the centers, and the manufacturing industry was focused on existing clusters. On the other hand, in the case of the life service industry, young people were active in startups near universities and cultural centers, while middle-aged people were concentrated on new towns. Third, there was a difference in factors that influenced the startup location of each generation in Seoul. For young people, high-tech industries, universities, cultural capital, and densely populated areas were significant factors for startup, and for middle-aged people, professional service areas, low average age, and the level of concentration of start-up support institutions had a significant influence on startup. Also, these location factors had different influences for each industry. The implications suggested through the study are as follows. First, it is necessary to support systematic startups considering the characteristics of each region, industry, and generation in Seoul. As there are significant differences in startup regions and industries by generation, it is necessary to strengthen a customized startup support system that takes into account these regional and industrial characteristics. Second, in terms of research methods, a follow-up study is needed that comprehensively considers culture and finance at the large districts(Gu) level through data accumulation.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.34 no.1
• /
• pp.83-96
• /
• 2016

Through the research and analysis on the vegetation environment, flora of habitats through documentary and field studies over 14 habitats of Euryale ferox Salisbury within Jeollabukdo, with the objective of acquiring the basic data for forming an environment based on plantation of reservoirs that are composed with Euryale ferox, the following results were obtained. 1. The entire flora of the 14 habitats appeared to be 79 families, 211 genus, 298 species, two subspecies, 30 varieties and six forma, thus, a total of 336 taxa was confirmed. Among these, emergent water plants appeared to compose 17 taxa, floating-leaved plants to compose seven taxa including Euryale ferox floating plants to compose five taxa and submerged water plants to compose two taxa. As a result of analyzing the similarity only over the water plants. The lowest similarity rate appeared between Gamdong Reservoir and Aedang Reservoir, as the similarity rate between the two regions appeared to be 0% as a result of the analysis. Floating-leaved plants, lotuses and caltrops, appeared to be equally inhabiting in Hanseongji at Jeongeup and Seoknam Reservoir at Gochang, which showed the highest similarity rate, in addition to Euryale ferox. 2. When examining the appearance frequency of aquatic plants per growth type, Actinostemma lobatum and Phragmites communis, in addition to Euryale ferox each appeared 11 times, showing a high frequency of 78.6% and Trapa japonica, which is a floating-leaved water plant, appeared ten times(71.4%) and Zizania latifolia appeared eight times(57.1%). In addition, the appearance rate appeared to be high in the order of Persicaria thunbergii, Leersia sayanuka, Ceratophyllum demersum, Echinochloa crusgalli var. oryzicola, Scirpus maritimus, and Nelumbo nucifera. 3. The rare plants discovered in the Euryale ferox habitats pursuant to the IUCN evaluation standards was confirmed to be composed of five taxa, with three taxa including the least concerned species(LC), Melothria japonica at Yanggok Reservoir, Hydrocharis dubia at Myeongdeokji and Ottelia alismoides at Daewi Reservoir, in addition to vulnerable species(VU), Utricularia vulgaris at Sangpyeong Reservoir, along with Euryale ferox. 4. Most of the group or community types of the natural habitats of Euryale ferox appeared to be the Euryale ferix community' and the Daewi Reservoir of Gunsan was defined as caltrop + Euryale ferox + Nymphoides indica community. The green coverage ratio of Euryale ferox per natural habitats showed a considerably huge deviation from 0.03 to 36.50 and as the average green coverage ratio was appropriated as 9.8, it can be considered that maintaining the green coverage ratio of Euryale ferox in a 10% level would be advisable when forming a reservoir with Euryale ferox as the key composition species. 5. The vegetation community nearby the natural habitats of Euryale ferox per research subject area appeared to be composed of three Leersia japonica communities, two communities each for Zizania latifolia community and Trapa japonica community and one community each for Nelumbo nucifera community, Nymphoides peltata + Typha orientalis community, Trapa japonica + Nelumbo nucifera community, Hydrocharis dubia community, Leersia japnica + Paspalum distichum var. indutum community and Euryale ferox + Trapa japonica community, showing a slight difference depending on the location conditions of each reservoir. Thus, this result may be suggested as a guideline to apply when allocating the vegetation ratio and the types of floating-leaved plants upon planting plants in reservoirs with Euryale ferox as the main companion species.