• East Asian Journal of Business Economics (EAJBE)
• /
• v.11 no.1
• /
• pp.53-71
• /
• 2023

Purpose - This study aims to find clues necessary for the direction of leadership development suitable for the current situation by exploring the direction in which leadership has been studied from the perspective of domestic researchers, along with the arrangement of leadership theories studied in various ways. Research design, data, and methodology - A total of 7,425 papers were obtained due to the search, and 5,810 papers with English abstracts were used for analysis. For analysis, word frequency analysis, word clouding, and co-occurrence were confirmed using Python 3.7. In addition, after classifying topics related to research trends through BERTopic and LDA, trends were identified through dynamic topic modeling and OLS regression analysis. Result - As a result of the BERTopic, 14 topics such as 'Leadership management and performance' and 'Sports leadership' were derived. As a result of conducting LDA on 1,976 outliers, five topics were derived. As a result of trend analysis on topics by year, it was confirmed that five topics, such as 'military police leadership' received relative attention. Conclusion - Through the results of this study, a study on the reinterpretation of past leadership studies, a study on LMX with an expanded perspective, and a study on integrated leadership sub-factors of modern leadership theory were proposed.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.25 no.3
• /
• pp.257-266
• /
• 2007

The research on red tide is generally in progress through field work, such as the naked eye and sampling. It was difficult to forecast exactly the course, from appearance of red tide to disappearance. with the established ways of investigation and analysis. Accordingly it is need to analyze environmental factors in time and space, the appearance of red tide and the path of its migration by more objective and scientific methods. In this study, GIS is applied to analyse the space character of red tide and the interpolation of IDW(Inverse Distance Weight) is applied to assume the density distribution of red tide after gather data by using Arc/Info. After IDW interpolation, the sea area occurred over 1,000 cells/ml of red tide density is extracted with CON and SUM Function of Grid Module, and the density of the sea area is accumulated daily. As a result of this study, the distribution condition of red tide is found timely and spacially by applying GIS to the sea area of red tide, the results indicated that the spatial density and the cumulative frequency about the origin of red tide using GIS, the sea area demonstrated that the maximum density and the maximum frequency varied significantly over the Nammyun of Namhae-Is. with the maximum frequency being 49 times. accordingly if data about the areas of red tide will occur from the present are accumulated, the shifting route of red tide occurrence and extinction can be predicted.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.32 no.2
• /
• pp.106-121
• /
• 2020

In order to make harbor outskirt facilities robust using the reliability-based design, probabilistic models of wave heights at varying stage of shoaling process optimized for Korean sea waves are prerequisite. In this rationale, we numerically simulate the nonlinear shoaling process of random waves over the beach with a sandbar at its foreshore. In doing so, comprehensive numerical models made of spatially filtered Navier-Stokes Eq., LES [Large Eddy Simulation], dynamic Smagorinsky turbulence closure were used. Considering the characteristics of swells observed at the east coast of Korean Peninsula, random waves were simulated using JONSWAP wave spectrum of various peak enhancement coefficients and random phase method. The coefficients of probabilistic models proposed in this study are estimated from the results of frequency analysis of wave crests and its associated trough detected by Wave by Wave Analysis of the time series of numerically simulated free surface displacements based on the threshold crossing method. Numerical results show that Modified Glukhovskiy wave height distribution, the most referred probabilistic models at finite water depth in the literature, over-predicts the occurring probability of relatively large and small wave heights, and under predicts the occurrence rate of waves of moderate heights. On the other hand, probabilistic models developed in this study show vary encouraging agreements. In addition, the discrepancy of the Modified Glukhovskiy distribution from the measured one are most visible over the surf zone, and as a result, the Modified Glukhovskiy distribution should be applied with caution for the reliability-based design of harbor outskirt facilities deployed near the surf-zone.

• Ocean and Polar Research
• /
• v.43 no.3
• /
• pp.127-140
• /
• 2021

At the estuaries of Bonggang and Miryong streams in the Korean southern coast, the spatiotemporal distribution and habitat environment of a nerite snail, Clithon retropictum (Gastropoda: Neritidae), which has been assigned as a legally protected species of Korea, were explored. Physicochemical environmental factors such as water temperature, salinity, tidal level distribution as well as biotic environments (chlorophyll-a concentration and epilithic microalgae composition) were monitored every month. The relationships between the environmental factors and spatiotemporal distribution of the nerite snail population were analyzed. Water temperature, salinity, and water level varied by season and lunar tidal rhythm. The spatiotemporal distribution of the nerite snail was mostly related to water salinity. Among epilithic algae which were the priority prey of snails, blue-green algae and green algae dominated in summer and autumn, while diatoms predominated during winter and spring. Chlorophyll-a concentration was highly and positively correlated with the population density of the nerite snail. The correlation coefficients were different depending on the taxon (Family) of epilithic algae. The mean population density was 302.2 inds m^-2 and 271.8 inds m^-2 in Bonggang Stream and Miryong Stream, respectively. The egg capsules of the nerite snail in the two habitats were observed from March (in Bonggang Stream) or April (in Miryong Stream) to August, and newly hatched juveniles recruited in the habitats from August were assessed with regard to frequency distributions of shell width. The occurrence of large-sized snails in upper stream reaches of both Bonggang and Miryong indicated the movement of spats from the mouth to the upper reaches during the whole life cycle.

• Korean Journal of Veterinary Research
• /
• v.29 no.3
• /
• pp.303-313
• /
• 1989

To investigate the epidemiological trait of intestinal diseases of animals caused by thermophilic Campyllobacter spp., isolation of etiological agent was carried out and the profiles of plasmids and the transfer of resistance plasmid in the isolated Campylobacter spp. were examined. The results were as follows. 1. A total of 110 isolates of C jejuni and C coli were subjected to the test for the presence of plasmid DNA. Of the isolates examined, 60% of the isolates were noted to harbor plasmid DNA. Plasmid occurrencer ate from pigs, chickens and cattle were 76.2%, 61.7% and 37.7%, respectively. The plasmids of a large molecular weight, ranging from 36 Md to 86Md, were identified with the strains of tetracycline resistant. 2. Transfer frequency of tetracycline resistant plasmids was higher in the case of the filter mating method than in the broth mating method by the factor of 10~1,000. 3. Tetracycline resistant plasmids of C jejuni were transferrable to C jejuni and C coli by conjugation. In a low frequency, the transfer of tetracycline plasmid was also possible to Vibrio parahemolyticus. However, it was impossible to transfer to Streptococcus fecalis, E coli and Vibrio cholerae. 4. Tetracycline resistant plasmids of C jejuni were impossible to transfer to Campylobacter spp. and related bacteria by transformation.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.17
• /
• pp.7125-7128
• /
• 2014

Background: Acquired genetic alterations and presence of sensitizing mutations in the tyrosine kinase domain of EGFR and other signaling molecules have been found in different subsets of primary lung adenocarcinoma. The commonest EGFR mutations are small in frame deletions of exon 19 and a point mutation (L858R) in exon 21, having a combined occurrence of around 90%. The objective of this study was to determine the frequency and types of EGFR mutations in primary lung adenocarcinomas in Pakistan. Materials and Methods: EGFR mutations in tumor samples were screened by multiplex real time PCR. Briefly, DNA from formalin fixed paraffin-embedded tissue was amplified with primers and probes specific to 43 different EGFR mutations in a Cobas z 480 instrument. The assay detects mutations in four exons (18-21) of the EGFR gene. Results: Out of 94 patients, 65 were males and 29 females with a M:F ratio of 2.2: 1. The median age was 62 years (range, 28 - 85 years). In our biopsy samples 70 (74%) cases were of primary lung adenocarcinoma, whereas 24 (26%) were confirmed metastatic adenocarcinoma of primary lung origin. EGFR mutation was positive in 29% of the patients. The highest frequency of L858R was observed in 48% of these, followed by deletion in exon 19 (44%). In addition, other rare mutations such as compound G718X:S768I and insertions in exon 20 insertion were detected in approximately 4% of the patients. Conclusions: This study showed that Del 19 and L858R are the most frequent mutations in Pakistani lung adenocarcinoma patients and around 29% of the patients were found eligible for erlotinib therapy.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.22 no.3
• /
• pp.171-180
• /
• 2010

Analysis on the temporal variation of the stratification is carried out by using the continuous water temperature and salinity data observed in the coastal monitoring buoy in Mikawa Bay, Japan. The main analysis results are as follows. The stratification pattern have an obvious and dominant 1-year period variation and the occurrence frequency (days) are exponentially decreased as the stratification intensity (SI) defined as the density difference between surface and bottom layers linearly increases. The frequency distribution function of the SI is presumably close to the log-normal function type or exponential function type. From the water temperature and salinity scatter diagram analysis, the line and loop type patterns are shown in the bottom and surface layers, respectively. In addition, the analysis of the SI estimation show that the error bound in case of using the weekly-monitoring data is about 4.45 times greater than that in case of using the continuous (daily) monitoring data.

• Journal of the Korea Institute of Building Construction
• /
• v.17 no.3
• /
• pp.287-294
• /
• 2017

Recently the construction project is becoming large-sized, complicated, and modernize. This has increased the uncertainty of construction risk. Therefore, studies should be followed regarding scientifically identifying the risk factors, quantifying the frequency and severity of risk factors in order to develop a model that can quantitatively evaluate and manage the risk for response the increased risk in construction. To address the problem, this study analyze the probability distribution of risk causes, the probability of occurrence and frequency of the specific risk level through Monte Carlo simulation method based on the accident data caused at construction sites. In the end, this study derives quantitative analysis by analyzing the amount of risk and probability distributions of accident causes. The results of this study will be a basis for future quantitative risk management models and risk management research.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.2 no.2
• /
• pp.35-44
• /
• 1998

Because of the continual occurrence of minor and moderate earthquakes in Korean peninsula, it is generally considered that Korean is not located in a safe region against probable earthquake any more, even though being recognized as a safe country in earthquake. It is in particular noted that nowadays there has been much concern about unexpected tragedy due to probable earthquake since the disaster of 1995 kobe earthquake. Thus, the objective of this research is to develop appropriate design spectrum which could be practicably used in seismic design of important structures taking into consideration of local physical characteristics. Particularly, we have to keep in mind the lessons from 1985 Mexico earthquake which had disregarded deep research on local ground conditions, being a possible magnification phenomena of ground motions in weak soil layer. Various spectra has been described based on the analysis of historical earthquakes, and generate the artificial ground acceleration. Also, rational numbers of artificial ground acceleration is investigated by the seismic analysis for skew slab bridges.

• Journal of the Korean Geographical Society
• /
• v.49 no.1
• /
• pp.32-44
• /
• 2014

This study aimed to analyze the characteristic of the distribution of minimum temperature during January in the central region of South Korea and to investigate causes for the occurrence of extreme minimum temperature in Cheorwon. January temperature distribution data which were collected from 25 weather stations in central area from 1991 to 2010 were investigated, and the difference of temperature between Cheorwon and the other stations in central region, such as Chuncheon, Hongcheon, Bonghwa, Daegwallyoung, Wonju and Jecheon were analyzed by the type of atmospheric pressure system. Daily mean temperature and mean of daily minimum temperature appear to be low at Cheorwon and at the sites in high altitudes, but the frequency of extreme cold wave such as below $-15^{\circ}C$ is also noticeable in Cheorwon. When the Siberian High has expanded and migratory anticyclone has moved onto the north of the Korean Peninsula, the temperature at Cheorwon is relatively low. Furthermore it shows a lesser difference between Cheorwon and the compared stations when the migratory anticyclone affected the area, even at basin like Bonghwa, Jecheon more lower than Cheorwon.