• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.794-798
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• 1996

Solid solutions of the nonstoichiometric Dy1-xSrxCoO3-y system with the compositions of x=0.00, 0.25, 0.50, 0.75, and 1.00 have been synthesized by the solid state reaction at 1000 ℃ under atmospheric air pressure. The crystallographic structures of the solid solutions are analyzed by the powder X-ray diffraction patterns at room temperature. The analyses assign the compositions of x=0.00 and 0.25 to the orthorhombic system with space group of Pbnm/D2h16, the compositions of x=0.50 and 0.75 to the tetragonal system like a typical SrCoO2.86, and the composition of x=l.00 or SrCoO2.50 to the brownmillerite type system with space group of I**a. The reduced lattice volumes increase with x value due to the larger radius of Sr2+ ion than that of Dy3+ ion. The mole ratio of Co4+ ion to total Co ion with mixed valence state between Co3+ and Co4+ ions at B sites or τ value has been determined by an iodometric titration. All the samples except for the DyCoO3 compound show the mixed valnce state and thus the composition of x=0.50 has the maximum τ value in the system. The oxygen vacancies increasing with x value are randomly distributed over the crystal lattice except for the composition of x=l.00 which have the ordering of the oxygen vacancies. The nonstoichiometric chemical formulas of the Dy1-xSrxCo3+1-τCo4+τO3-(x-τ)/2 system are formulated from the x, τ, and y values. The electrical conductivity in the temperature range of 100 to 900 K increases with τ value linearly because of positive holes of the Co4+ ions in π* band as a conducting carrier. The activation energy of the x=0.50 as Ea=0.17 eV is minimum among other compouds. Broad and high order transition due to the overlap between σ* and π* bands broadened by the thermal activation is observed near 1000 K and shows a low temperature-semiconducting behavior. Magnetic properties following the Currie-Weiss law show the low to high spin transition in the cobaltate perovskite. Especially, the composition of x=0.75 presents weak ferromagnetic behavior due to the Co3+-O2--Co4+ indirect superexchange interaction.

• Journal of the Korean association of regional geographers
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• v.6 no.1
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• pp.1-28
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• 2000

The purpose of this study is to clarify the suburbanization of manufacturing, and location and linkages of decentralized manufacturing from Metropolitan Pusan by means of case study on manufacturing location and linkages in the suburb of Metropolitan Pusan. Kimhae city and Yangsan-Gun toward which heavy decentralization of manufacturing from the Metropolitan Pusan has been done. Both hard data and soft data were used as the basic data. Hard data are the statistical data in statistical yearbooks and firm list in directories. The former consists of the number of establishments and employees classified by product type, firm size and unit area. The latter consists of owner's names, addresses, employee number, products and headquarters of firms. Soft data are the results of the interviews with the 242 owners of firms in the four case study areas selected by Proportional Stratified Sampling Method. The major findings are as follows: 1. The spatial variations of manufacturing in the suburb was regularized in the latter half of 1970's. The primary processes to decentralize manufacturing from Metropolitan Pusan were the birth, relocation and establishment of branches of the firms. Among them the relocation of small outer-oriented single-location firms from Pusan was the most important. 2. The spatial variations undergoing spatial expansion of manufacturing distribution and increase of agglomeration degree of manufacturing, proceeded from the adjacents of Metropolitan Pusan to the outer areas along the main transportation route. 3. The main factors which caused manufacturing to decentralize from the Metropolitan Pusan were firm policy and land for this policy. The main locational factors which induced the decentralizing manufacturing into the suburb were land, market and transportation. 4. The strength of linkages with the outside of the study area is stronger than that of linkages with the inside. There is distance-decay-function in the strength of linkages with the outside, and linkages with short distant areas are stronger than those with long distant areas. 5. The ranges of spatial linkages in procurement of materials, in subcontraction and in marketing are wider than those in ordering. 6. The main factors which cause the formation of linkages are different by types of linkages: monopolistic and oligopolistic supply are important in procurement linkages; characteristics of products and the subsequent marketing difficulties, in subcontraction linkages; fluctuation, cost reduction, insufficient facility and characteristics of products, in ordering linkages; subcontract, characteristics of product and the subsequent marketing difficulties, in marketing linkages. 7. The changes of linkages owing to locational changes of firms were great, and were greater in long distant areas than in short distant areas. 8. The main factor influencing on the changes of linkages was the easiness in the transportation of goods, movement of labour and contacts with customers. In conclusion, some facts described above were proved to be consistent with the results of proceeding studies in the other areas: influence of relocation of decentralizing firms on the suburbanization; the factors of manufacturing decentralization; spatial characteristics of linkages; linkage changes owing to relocation of firms. Some were proved to be partly consistent: locational factors inducing decentralized manufacturing into the suburb were proved to be inconsistent. I think that the results of previous studies on the other areas can be applicable to the explanation on the decentralization of Metropolitan manufacturing from the viewpoint of the suburb. For the better explanation on the decentralization of Metropolitan manufacturing, more empirical case studies on the suburbanization of manufacturing are necessary.

• Journal of the Korean Society of Safety
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• v.35 no.3
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• pp.64-71
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• 2020

Safety is not a service provided selectively by the country, and it is a basic right that human beings should enjoy. However, as the recent expansion of outsourcing due to the efficient corporate management, fatal accidents such as the Taean Power Plant where subcontractors are pinched on conveyors continued to occur. In addition, public safety concerns have been widespread as there are constant safety-related accidents in public institutions such as KTX trains derailing. As public institutions require safety as a top priority for management rather than profit, the government needs a leading role to enhance the level of private safety activities. The government announced the "Measures to strengthen the workplace safety of public institutions" and is promoting measures to protect the lives and safety of the people. The purpose of this study was to in-depth analysis of the accident and death situation in public institutions in the last 5 years from 2014 to 2018. A recognition survey was also conducted and the results were analyzed. As a result of the analysis of industrial accident death, it showed that the number of industrial accident deaths in public institutions was about 50 people per year, and it occupied about 6.1% of all industrial accidents. Following the government's public policy measures, positive changes as a result of the survey on awareness were detected in the order of rising safety awareness and participation of management (56.9%), safety and health organization and personnel composition (37.9%), and increasing safety awareness and participation of members (18.9%). However, the obstacles to the implementation of government measures were followings; 1) consciousness and lack of participation (42.1%), 2) indifference from other departments (35.1%), 3) absence, or lack of competency of safety manager (33.3%). In addition, safety investments and safety management of contractors and ordering works were analyzed to have remained largely unchanged even after the implementation of safety measures. Through this study, it is intended to provide basic data for strengthening the level and activities of safety in public institutions.

• Journal of the Korean Society for Marine Environment & Energy
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• v.20 no.1
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• pp.18-25
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• 2017

Damage of both life and property has been increased by natural disaster under the influence of climate change, thus many natural disaster vulnerability researches have been carried out to make adaptation policy and impact assessment of climate change recently. Their method for assessing vulnerability usually have used proxy variables for making vulnerability indices. However, because their results were too qualitative and relative it tends to be hard to make absolute comparison and establish standard of prevention or adaptation ability. Accordingly, this study aimed at quantifying natural disaster vulnerability using emergy through recognizing disaster as the relations between order and disorder by system approach. As a result, ordering energy (4.66E+22 sej/yr) and ordered structure (1.98E+22 sej) of Busan in 2003 and disordering energy (7.80E+18 sej), disordered parts (4.55E+20 sej) and rebuilding energy (3.87E+20 sej) by typhoon Maemi were analysed. And then, this was compared with Hurricane Andrew in Dade County. Through this comparison, if the prevention ability of Busan increases, disordered parts can be reduced against the more powerful disordering energy. Also, prevention for additional damages by disaster is needed to practical rebuilding action. In conclusion, it was able to figure out the impact of disaster quantitatively by natural systems and urban systems showing as common measure. Based on this study and further research to make effective prevention for how much prevention ability should be increased will contribute to producing the scientific data for disaster management policy in future.

• Journal of the Korean Society for information Management
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• v.23 no.1 s.59
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• pp.121-138
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• 2006

This study attempts to derive an economic analysis model for journal evaluation and conducts a case analysis based on the model. Total costs are calculated and include administrative fees (such as binding, ordering, claiming, etc.) and subscription costs. The model quantifies qualitative benefits to users, a utility that combines usage data that has also been evaluated in the existing economic analysis models. The model is designed by the usage statistics of the web-based electronic journals, which have become important resources for research. Rankings are assigned based on how items are utilized to the goal of the mother institution. In the case study based on the KDI School Library, the highest ranking off was assigned to journals that patrons used for citation in their outputs. For journals that were used background information, i.e., full text downloading or browsing , each was assigned ranking of 2 and 1, respectively. According to the analysis, the top 20 journals provided 75% of the entire library utility, showing different user behaviors among different cohorts. We expect that the model makes it possible for librarians to measure the value of journals. It can provide a basic tool for journal selection, particularly in special libraries with custom needs.

• Journal of Venture Innovation
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• v.1 no.1
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• pp.15-27
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• 2018

Interest in Fintech is extremely growing as O2O which means the binding of online and offline appears. The scale of private consumption in South korea reached about 700 trillion won, however, the online trading is only about 60 trillion won, which means 640 trillion won is still trading in offline. The reason the Fintech industry comes into the spotlight is because the foundation of related industries such as the rise of mobile traffic and the fast growth of the financial transaction through the mobile channel is forming. Especially, the introduction of payment systems among these Fintech industries offers convenience to the consumer. Mobile payment has been generalized in daily life such as utility bills and taxi fares. Use of O2O service in various industrial fields in commerce gives convenience to consumers and increase in sales to business in recent commercial transaction which is moving to on-demand channel services. People in smartphone life are supposed to find more convenient services for saving time using their phone, and this kind of environment makes the ordering goods and services through Fintech payments increase. The emergence of O2O services influences the development of Fintech industry and the emergence of convenient and reliable Fintech service through the deregulation of Fintech also affects the activation of O2O services. The complementary relationships between O2O services and Fintech would contribute to economic activation. From the standpoint of the researchers, I would like to further study the methods that can lead to a new paradigm of the financial payments industry through the development of Fintech and the drafts for the market expansion of the current offline commerce making it online in the advent of O2O services in variety industries.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.260-260
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• 2013

Multiferroic materials have attracted much attention due to their fascinating fundamental physical properties and technological applications in magnetic/ferroelectric data-storage systems, quantum electromagnets, spintronics, and sensor devices. Among single-phase multiferroic materials, $BiFeO_3 $ is a typical multiferroic material with a room temperature magnetoelectric coupling in view of high magnetic-and ferroelectric-ordering temperatures (Neel temperature $T_N$~647 K and Curie temperature $T_C$~1,103 K). Rare-earth ion substitution at the Bi sties is very interesting, which induces suppressed volatility of Bi ion and improved ferroelectric properties. At the same time, Fe-site substitution with magnetic ions is also attracting, and the enhanced ferromagnetism was reported. In this study, $Bi_{1-x}Dy_xFe_{0.95}Co_{0.05}O_3$ (x=0, 0.05 and 0.1) bulk ceramic compounds were prepared by solid-state reaction and rapid sintering. High-purity $Bi_2O_3$, $Dy_2O_3$, $Fe_2O_3$ and $Co_3O_4$ powders with the stoichiometric proportions were mixed, and calcined at $500^{\circ}C$ or 24 h to produce $Bi_{1-x}Dy_xFe_{0.95}Co_{0.05}O_3$. The samples were immediately put into an oven, which was heated up to $800^{\circ}C$ nd sintered in air for 30 min. The crystalline structure of samples was investigated at room temperature by using a Rigaku Miniflex powder diffractometer. The field-dependent magnetization measurements were performed with a vibrating-sample magnetometer. The electric polarization was measured at room temperature by using a standard ferroelectric tester (RT66B, Radiant Technologies).

• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.3
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• pp.87-101
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• 1990

The purpose of this study is to estimate the flood discharge and runoff volume at a stream by using geomorphologic parameters obtained from the topographic maps following the law of stream classification and ordering by Horton and Strahier. The present model is modified from Cheng' s model which derives the geomorphologic instantaneous unit hydrograph. The present model uses the results of Laplace transformation and convolution intergral of probability density function of the travel time at each state. The stream flow velocity parameters are determined as a function of the rainfall intensity, and the effective rainfall is calculated by the SCS method. The total direct runoff volume until the time to peak is estimated by assuming a triangular hydrograph. The model is used to estimate the time to peak, the flood discharge, and the direct runoff at Andong, Imha. Geomchon, and Sunsan basin in the Nakdong River system. The results of the model application are as follows : 1.For each basin, as the rainfall intensity doubles form 1 mm/h to 2 mm/h with the same rainfall duration of 1 hour, the hydrographs show that the runoff volume doubles while the duration of the base flow and the time to peak are the same. This aggrees with the theory of the unit hydrograph. 2.Comparisions of the model predicted and observed values show that small relative errors of 0.44-7.4% of the flood discharge, and 1 hour difference in time to peak except the Geomchon basin which shows 10.32% and 2 hours respectively. 3.When the rainfall intensity is small, the error of flood discharge estimated by using this model is relatively large. The reason of this might be because of introducing the flood velocity concept in the stream flow velocity. 4.Total direct runoff volume until the time to peak estimated by using this model has small relative error comparing with the observed data. 5.The sensitivity analysis of velocity parameters to flood discharge shows that the flood discharge is sensitive to the velocity coefficient while it is insensitive to the ratio of arrival time of moving portion to that of storage portion of a stream and to the ratio of arrival time of stream to that of overland flow.

• Journal of Korean Academy of Nursing
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• v.29 no.4
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• pp.880-891
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• 1999

The purpose of this study was to describe nursing decision tasks, their characteristics, and problems associated with decision making. The subjects were 32 nurses who had at least one-year nursing experience and worked on medical-surgical units or intensive care units(ICU). They were asked to describe their decision making experiences in patient care situations and to identify the characteristics of each decisions. They were also asked to describe perceived problems associated with decision making in nursing. The responses on nursing decision tasks and problems were analyzed with content analysis and the decision characteristics were identified by statistical analysis of variance. It was found that there were 16 nursing decisions which are as follows : decisions related to interpreting and selecting appropriate strategies for pain management(6.6%) ; decisions related to providing emotional support (0.7%) ; decisions related to explaining the patient's condition and rationale for procedures(1.1%) ; decisions related to assisting patients to integrate the implications of illness and recovering into their lifestyles(2.9%) ; decisions related to detecting significant changes In patients and selecting appropriate intervention strategies (17.2%) ; decisions related to anticipating problems and selecting preventive measures(4.2%) ; decisions related to identifying emergency situations(0.4%) ; decisions related to effective management of patient crisis until physician assistance becomes available(2.8%) ; decisions related to starting and maintaining intravenous therapy(2.6%) ; decisions related to administering medications(8.1%) ; decisions related to combating the hazards of immobility(7.3%) : decisions related to treating wound management strategies(5.5%) ; decisions related to relieving patient discomfort(13.9) ; decisions related to selecting appropriate strategy according to the changing situation of the patient(18.2%) ; decisions related to selecting the best strategy for patient management(5.3%) ; and decisions related to coordinating, ordering, and meeting the various needs of the patient (3.1%). The nurses reported the fellowing problems in decision making : difficulties due to lack of knowledge and experience (18.6%) ; uncertainty and complexity of decision tasks(15.2%) ; lack of time to make decisions(2.9%) ; personal values which conflict with other staff(15.7%) ; lack of selection autonomy(30.0%) ; and organizational barriers(7.6%). Continuing education programs and decision support systems for frequent nursing decision tasks can be established on the basis of these results. Then decision ability in nurses will increase through the education programs and decision support systems, and then quality of nursing service will be better.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2516-2522
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• 2009

The data which analyze the results of blood cultures are crucial basic information of the empirical therapy for patients with infection since the patterns of the species of microorganism isolated from blood and the results of antibiotic susceptibility test vary depending upon patients general features. Especially, in case of ESBL-producing bacteria, there is a close relation with use of antibiotics. Therefore, we carried out the research with the results of blood culture and antibiotic. 1. Total 39,305 cases of blood culture samples were investigated and positive patients of 2,216 (20.0%) were found. Among those, there were 40 patients with ESBL positive, and blood culture positive samples were 4,798 (12.2%). ESBL positive bacteria were found in 86 samples (including double checked culture bacteria). 2. The majority of ESBL producing bacteria were E. coli, K. pneumoniae and K. oxitoca as ordering based on the number. 3. The research showed the results that there were more females than male with the bacterias, more E. coli in over 50 years old aged group than other bacterias, more K. pneumoniae and K.oxitoca in less 1 year old aged group than other bacterias and largest numbers of patients with 13 patients (32.5%) in Chungcheongnam-do province were found. 4. The most common ESBL producing bacteria were E. coli throughout 3 years, but K, pneumoniae and K. oxitoca were also fairly found. Interestingly, E. coli was highly found in over 50 years old patients.