• Korean Journal of Remote Sensing
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• v.35 no.6_2
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• pp.1149-1160
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• 2019

In this study, two radiometric correction methods deriving reflectance from UAV multispectral image for monitoring forest vegetation were applied and evaluated. Multispectral images were obtained from a small multispectral camera having 5 spectral bands. Reflectance were derived by applying the two methods: (1) the direct method using downwelling irradiance measurement and (2) the empirical line correction method by linking a set of field reflectance measured simultaneous with the image capture. Field reflectance were obtained using a spectroradiometer during the flight and used for building the linear equation for the empirical method and for the validation of image reflectance derived. Although both methods provided the high correlations between field reflectance and image-derived reflectance, their distributions were somewhat different. While the direct method provided rather stable and consistent distribution of reflectance all over the entire image area, the empirical method showed very unstable and inconsistent reflectance distribution. The direct method would be more appropriate for relatively wide area that requires more time to acquire image and may vary in downwelling irradiance and atmospheric conditions.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.57-72
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• 2018

Organic agriculture seeks sustainable agriculture. Organic agriculture is based on circulating agriculture of a family farm unit. However, as of the end of 2016, only 33 out of the total organic farming farms were implementing Crop-Livestock cycling organic farming. The reason seems to be a matter of income after all. The optimal size combination refers to the scale by which family farms can maintain their quality of life while engaging in farming activities. In other words. it is a farm scale that maintains optimal income through stable labor costs. In the meantime, there has been no previous study on the optimal economical combination of Crop-Livestock cycling farming. Choi (2016) analyzed whether the economies of scope (EOS) were realized in the combined production by using the management data of the farmers who practiced Crop-Livestock cycling organic farming for four years. As a result, it has been revealed that the EOS measurement value is 0 or more so the economies of scope are being realized. Therefore, the purpose of this empirical analysis is to identify farm incomes under this circumstance. It is assumed that the optimum production is achieved by balancing the total income curve and the total cost curve in the optimal scale production range. The results of the analysis are as follows. First, the income after the conversion to Crop-Livestock cycling farming was 44,789,280 won, the sum of the seedling-livestock sector, which was 17,873,120 won higher when the non-Crop-Livestock cycling farming was assumed. The same is true for 2014 and 2015. The reason for this is that pig droppings were composted from organic seedlings, and the cost of selling pork was 150,000 won/per pig more expensive even though the manufacturing cost of organic feeds was higher than the purchasing cost. Secondly, this study simulated the result that the economic index varies when the farm size combination is changed by the farm size of 100% standard (S100) as of 2014. S130 is the increase in size from 100% of 2014, whereas S30 is the result of 3ha crop and 66 livestock (pigs). As a result of this simulation, Crop-Livestock cycling farming income decreased more than non-Crop-Livestock cycling farming as the farm size decreased, whereas the income decreased as the farm size increased. When the size was reduced below S50, the income tended to decrease. In this situation, EOS changed in the same direction. The results showed that when the farming size was reorganized and reduced to 50% compared to 2014, the income and income difference was the highest. At the same time, economies of scope (EOS) were the highest at 0.12985. In other words, it was found that the income of farm houses in a family farm unit sector was the best in the combination of 1.5ha crop agriculture and 110 livestock (pigs).

• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.124-133
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• 2009

Effects of substrates on the relative immigration activities (RIAs) of epilithic diatoms were examined in Sum River, a tributary of South Han River, Korea. Two hundreds of tile substrates coated with 5% agar were deposited at seven study stations (30 tiles per site) for one month from March 7 to April 7, 2008. Water sampling, physico-chemical factor measurement, and diatom analysis were performed in the field and laboratory. Over the study, major epilithic diatom species were Nitzschia amphibia, Navicula subminuscula, Cymbella minuta in both the natural and artificial substrates. Two dominant species, Nitzschia amphibia and Cymbella minuta often found at seven stations. Among all observed taxa, Nav. subminuscula and Caloneis silicula showed the highest RIA, with the value over 15 throughout the study. Regarding the algal morphology, the biraphe type species showed higher RIA than any other morph, while they comprised over 55% of total biomass, indicating a density effect. Additionally, a significant relationship between RIA and 20-day deposited substrate (p<0.05) showed in two diatom species, Nitzschia fonticola, Gomphonema quadripunctatum, which showed relatively high RIAs. These results indicate that the relative immigration activities of epilithic diatom species can be influenced by algal density in the water and substrate, nutrients, and deposited time at least 20 days.

• Journal of Information Management
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• v.37 no.4
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• pp.69-91
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• 2006

The purpose of this study is to improve the effectiveness and quality of web service by analyzing the web service problems and suggesting the solutions through the expert service quality evaluation from the point of view of users and website quality evaluation by measurement tools for a whole NDSL website. In case of website analysis, this study analyzed the website completeness of NDSL site and looked into the problem that users can judge by intuition during their use of the site, and evaluated the searchability and usability for web-based service quality evaluation by centering on the service quality of database quality items. After the results of this analysis, it appeared that there was not a big problem on the use. But after searching, several problems were found on loading rates, website completeness, user sensitiveness, the protection of private information, metadata completeness, website accessability, etc. And as a result of the evaluation of website service quality, it does not show the all satisfactory results in the function of search methods and search result printing, mark list and the items related to full-text in the part of searchability and usability. However, comparing with the results of other information organizations, it shows the similar level of quality.

• Restorative Dentistry and Endodontics
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• v.35 no.6
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• pp.429-435
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• 2010

Objectives: The aim of this study was to investigate average working lengths of Korean posterior teeth and evaluate validity of endodontic file length. Materials and Methods: The endodontic working length of the posterior teeth of 670 Korean patients were measured than each mean value and standard deviation were investigated than the frequency deviation and standard deviation per each length were calculated. Results: Among the canals of premolar, 66.5% of canal length was marked under 20 mm by endodontic working length and 95.4% could be measured under 22 mm and Among the canals of molars, 95.5% of canal length was marked under 20 mm endodontic working length. Conclusions: With the result of measurement of endodontic working length of premolars of Korean, it suggested that 23 mm endodontic file is more proper than the 21 mm and 25 mm file on the market.

• Journal of Distribution Science
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• v.13 no.1
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• pp.35-46
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• 2015

Purpose - This paper attempted to investigate the relationships among the perception of job insecurity and organizational effectiveness, and it examines these relationships while considering the moderating effect of trust in the manager and self-efficacy. Job insecurity is an independent variable, organizational effectiveness aspects (job satisfaction, organizational commitment, and turnover intention) are dependent variables, and trust and self-efficacy are moderators. Research design, data, and methodology - Regression analysis was used to verify the effects. The measurement items were already deemed as reliable and valid in the previous study, but for this purpose, some modifications were made. To examine the model, this study relied on the samples chosen from Korean employees in the six franchise business firms. The survey was conducted on 288 workers. Each question is based on a 5-point Likert type scale. The data were analyzed using SPSS 18.0. Results - The results of the study are summarized as follows. First, job insecurity has an influence on organizational effectiveness aspects (negatively on job satisfaction, negatively on organizational commitment, and positively on turnover intention). Second, analyzing the moderating effect of trust, trust in manager is mediated between job insecurity and organizational effectiveness aspects (on organizational commitment and on turnover intention). However, employees' trust in manager had no significant moderating effect on the job insecurity-job satisfaction relationship. Third, self-efficacy is mediated between job insecurity and organizational effectiveness aspects (on job satisfaction, on organizational commitment, and on turnover intention). Conclusions - First, it is necessary to be aware of the seriousness of employees' job insecurity in franchise firms, which have played a pivotal role in national economic growth, and to create a detailed plan for reducing insecurity and actively implementing it. To this end, the franchise companies should implement efficiency efforts such as obtaining an appropriate capacity of equipped personnel and a training program. Second, there are moderating effects of self-efficacy and trust in the relationship between job insecurity and organizational effectiveness. Depending on business conditions, stability and instability can only be experienced in the organizations of franchise companies. This can give rise to instability in employment. Therefore, it is necessary to develop and utilize a system that can be minimized with a change in the new awareness of employment instability. After all, a good leader (manager) must accumulate personal trust and build up a core competence that is necessary to become competent in the field himself. Even if you lack the material resources to improve performance, if the leader with the core competencies (e.g., technical/management /organization/marketing/design) can gain the trust of the supervisor, you can get a good organizational performance. Therefore, you should foster a healthy organizational culture through education such as leadership training and employee training to be built on trust between the leaders and the employees. In addition, you need to focus on HRD&M training in order to increase the self-efficacy of the supervisor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.94-102
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• 1991

This study was directed to further clarify the effect of resting time or dietary condition for the improvement of exercise capacity and physical fitness, and the changes of some body consitiuents and physiological functions which are related to the exercise metabolism. Sixteen male students(8 athletes and 8 nonathletes)were participated during 3 weeks(Aug. 20-Sep.9, 1989). Each subject performed two treadmill running trials at an absolute intensity (1 mintute in 3.4mph/15% slope and 2 minutes in 5.5mph/20% slope). In the resting time trials, general diet was fed before 1, 2, 4 and 12 hours of the treadmill exercise loaded. in the dietary condition trials, high carbohydrate(HC), high fat(HF) and high protein(HP) diet were fed before 2 hours of the treadmill exercise loaded. Control trial was that of resting time before treadmill exercise loaded after 12 hours of general diet feeding. Measurement were made to study the change of blood glucose, palmitate, lactate, blood pressure and heart rate. The results obtained are summarized as follows: Mean daily metabolizable period. In resting time trial, the blood glucose concentration of athlete and nonathlete from 2 hours group was similar to control group. The blood palmitate concentration of athlete was increased in 1 and 2 hours group but those of nonathlete was not only increased in 1 and2 hours group but was more increased in 12 hours group, compared with both control group. The blood lactate concentration was increased in all experimental group, compared with both control group and those of nonathlete was much higher than athlets. The elevation rate of blood pressure in pre-and after-exercise of athlete was lower than those of nonathlete. In dietary composition trial, the blood glucose concentration of athlete and nonathlete in HC group was higher than other diet groups. The blood lactate concentration of athlete and nonathlete in HC group was lower than other diet groups. There was no remarkable change of the blood palmitate concentration and heart rate in each dietary composition trial, but those of nonathlete was low in HC and high in HP group. In above results, it was suggested that the effective condition of resting time and dietary composition for the improvement of exercise capacity of nonathlete may be 2 hours and HC diet, respectively. But it was showed that the exercise capacity of athlete may not be affected by experimental condition of resting time, except 1 hour after feeding or of dietary composition because of well adaptation in new exercise condition.

• Korean Journal of Remote Sensing
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• v.16 no.3
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• pp.221-233
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• 2000

An intertidal topography is continuously changed due to morphodynamics processes. Detection and measurement of topographic change for a tidal flat is important to make an integrated coastal area management plan as well as to carry out sedimentologic study. The objective of this study is to generate intertidal DEM using leveling data and waterlines extracted from optical and microwave remotely sensed data in a relatively short period. Waterline is defined as the border line between exposed tidal flat and water body. The contour of the terrain height in tidal flat is equivalent to the waterline. One can utilize satellite images to generate intertidal DEM over large areas. Extraction of the waterline in a SAR image is a difficult task to perform partly because of the presence of speckle and partly because of similarity between the signal returned from the sea surface and that from the exposed tidal flat surface or land. Waterlines in SAR intensity and coherence map can effectively be extracted with MSP-RoA edge detector. From multiple images obtained over a range of tide elevation, it is possible to build up a set of heighted waterline within intertidal zone, and then a gridded DEM can be interpolated. We have tested the proposed method over the Gomso Bay, and succeeded in generating intertidal DEM with relatively high accuracy.

• Korean Journal of Social Welfare Studies
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• v.47 no.4
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• pp.333-360
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• 2016

Social Impact Bonds(SIBs) has emerged as a promising way to finance proven social services programs, fund what works, and drive government accountability and has increased fast. In this context, this study examines and classifies the structure of SIB focusing key criteria of the main steps through two-step cluster analysis. Analysis results are as follows. First, the main commissioners of SIB are the ministries of the central government. And in terms of the stage of invest, there are usually two or three investors mainly consisting of social finance organizations. Second, in terms of target and age of SIB beneficiaries, it focuses on the adolescent and youth. Third, in the outcome evaluation stage, the results show that in most cases outcome payments are determined by a validation of service provider or government administrative data. However, the rate of payments are based on the comparison of the program beneficiaries to other comparable groups is 23.8%. Finally, The results of two-step cluster analysis are as; 'mix of central government and social finance organization', 'multiple agent including private organization', and 'multiple social provider'. Among three types, 'multiple agent including private organization' shows the most active participation between agents and the most systematic outcome measurement and management. The results of this study imply that the importance of the method to manage and measure outcome in SIB structure. Moreover, the consist of commissioners or investors is needed to expanded more.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.298-309
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• 2019

Objectives: This study aimed to investigate stages of safety and health culture change through a reflection on 40 years of hearing conservation history at a multinational company. Methods: The target workplaces were multinational companies with more than 1,000 employees. The research used the clinical case study and system analysis methods based on direct observation of the research from 1994 to 2009. The latter method performed an analysis of the equilibrium state of the cross-section in the given period and the longitudinal profile of the change during the given period. Results: The stages of cultural change are divided into five stages and summarized as follows. In the first stage, workplace noise was not widely recognized as a hazard, while in the second stage, the measurement of noise levels and audiometric testing were conducted under the Korean Occupational Safety and Health Act (KOSHA). The driving force for change in the second stage was the amendment of the KOSHA. In the third stage, noise came to be recognized as a hazard factor through awareness training. The driving force of change during the third stage was the strong executive power exerted by the audit of the industrial hygiene program from the US head office. In the fourth step, there was a change to actually reduce noise. The driving force in this stage was a change in company executives' risk perception resulting from lawsuits over noise-induced hearing loss and the task force team activities for culture change based on the action learning protocol. At the fifth stage, a 'buy quiet policy' was institutionalized. The management's experience that noise reduction was difficult was the motivation to manage noise from the time of purchase of equipment. Conclusions: The activities of a hearing conservation program are determined by the improvement of the legal system and by the way it is enforced. Noise control activities to reduce noise areas may be possible through the shared risk perception of noise-induced hearing loss and by a change agent role as a facilitator to implement noise control.