• Journal of Distribution Science
• /
• v.12 no.4
• /
• pp.23-30
• /
• 2014

Purpose - The purpose of this study is to analyze the efficiency of retail businesses by dividing domestic retailers into discount stores, super supermarkets (SSMs), and department stores. It suggests retail-business investment strategies by using data environment analysis (DEA) to analyze how input elements such as store area, parking lot area, number of employees, and sales management expenses for the convenience of customers positively affect business performance measurements such as sales and visiting customers per day. Research Design, Data, and Methodology - The DEA model calculates a ratio of the weighted mean of various inputs to the weighted mean of various outputs and measures the efficiency of a specific decision making unit (DMU). The study included 19 companies (five discount store DMUs, ten SSM DMUs, and four department store DMUs). Because the business elements and sizes of retail store DMUs used in this analysis are different, average per-store input and output variables were used. Data were collected from "The Yearbook of Retail Industry in Korea (2012)." DEA analysis was used to determine differences in efficiency among discount stores, SSMs, and department stores in terms of the business elements of each retail business. It was also used to determine what business elements were excessively invested in by comparing and analyzing efficiency by business elements using SPSS software's ANOVA (Analysis of Variance). Results - The CCR and BCC efficiency analysis found that the efficiency of discount stores is low. We believe that the saturation state of discount stores is a major factor. The ANOVA analysis confirms the VRS hypothesis with a statistically significant difference among the three groups, based on an analysis confidence interval of 95%. CRS and SE were not found to be significantly different among the three groups. As for the post hoc test, which concretely shows differences by group, the Scheffe's multiple comparison analysis test found the average differences between group 1 (discount stores) and group 2 (SSM) to be statistically significant. Conclusions - The DEA efficiency analysis implies that investment in input elements, including store area, parking lot area, and sales management expenses, were excessive in the case of discount stores, while SSMs need to invest more in promotion activities such as gifts, events, and coupons for customer management. Department stores have found that small companies invest excessively in input elements. Department stores need to invest in differentiated shopping mall complexes. This study was limited in acquiring statistical data; various input variables which might have shown more secure customer management and promotional expenses could not be applied. As the study was limited in various aspects of the efficiency analyses because financial analyses of the companies and of causal relationships, including satisfaction and loyalty of visiting customers, were not done, these aspects will be examined in the next study.

• Current Photovoltaic Research
• /
• v.8 no.3
• /
• pp.67-78
• /
• 2020

A novel energy production system which has fascinated a wide consideration because of its several benefits that are called floating photovoltaic technology (FPVT). The FPVT system that helps to minimize the evaporation of water as well as an increase in energy production. For the research purposes, both electrical and mechanical structure requires studying of these systems for the development of FPVT power plants. From different points of views, numerous researches have been directed on FPVT systems that have evaluated these systems. The present research article give a logical investigation and up to date review that shows the different features and components of FPVT systems as an energy production system is offered. This articles reviewing the FPVT that gets the attention of the scientists who have the investigational stage and involuntary inspection of FPVT systems in addition to influence of implementing these systems on the water surface. Also, a comprehensive comparison has been constructed that shows the cons and pros of various types of solar systems that could be installed in various locations. In this review, it has been found that solar energy on the roof of a dwelling house generally has a power of 5 to 20 kW, while the inhabitants of commercial buildings generally have a power of 100 kW or more. The average power capacity of a floating solar panel is 11% more of the average capacity of a solar panel installed on the ground. Studies show that 40% of the water in open reservoirs is lost through evaporation. By covering only 30% of the water surface, evaporation can be reduced by 49%. The global solar panel market exceeds 100 GW and the capacity of 104 GW will bring the annual growth rate to 6%. In 2018, the world's total photovoltaic capacity reached 512 GW, an increase of 27% compared to the total capacity and about 55% of the renewable resources newly created that come from photovoltaic systems. It has been also predicted by this review that in 2025 the Solar technology including the FPVT system will increase by 7.38% that is 485.4 GW more of today installed power worldwide.

• The Journal of the Korea Contents Association
• /
• v.20 no.11
• /
• pp.511-524
• /
• 2020

Purpose: This study aims to examine the effect of increased physical activity (PA) regarding health-related quality of life (QOL) and nutrition intake in hemodialysis patients. Methods: The research was quasi-experimental using pre-test and posttest design. The participants were 60 patients, 30 each in the experimental and control group. The program was up to eight weeks long and involved two kinds of aerobic exercises: intradialytic aerobic exercise to be performed thrice a week and walking for up to seven days a week. The 60 patients undergoing hemodialysis for end-stage renal disease underwent assessment of International Physical Activity Questionnaires (IPAQ), 24-hour diet recall and a 12-item short-form health survey (SF-12; physical component summary score(PCS) and mental component summary score(MCS)) before and after the exercise program. Nutrition intake was assessed using CAN-2.0. Data were analyzed using descriptive statistics, independent t-test, 𝑥2 test, and Mann-Whitney U test. Results: In the experimental group, PA post-test scores were also significantly higher than the pre-test scores and the levels of physical component summary score (PCS) in QOL were significantly improved post-test, but the scores on nutrient intake did not improve. The levels of PCS were significant correlations animal protein, manganese, selenium, and Vitamin C. Although there was no group effect, total calorie of nutrition intake was higher than the comparison group. Conclusion: Combined intradialytic exercise and walking was found to be effective on PA, and PCS in QOL. Therefore, the findings of the current study may provide an appropriate guidance for encouraging exercise by hemodialysis patient.

• Journal of Korean Academy of Fundamentals of Nursing
• /
• v.11 no.2
• /
• pp.124-137
• /
• 2004

Purpose: The purpose of this study was to examine differences in the perceived importance and frequency of nurse role behaviors for medical and surgical nurses and to examine the relationship between perceived importance and frequency of nurse role behaviors in the two groups. Method: A descriptive design was used with convenience sampling of 351 medical and surgical nurses in the 40 hospitals with over 500 beds. Data were collected using a structured questionnaire. Results: 1) The total score for perceived importance of nurse role behaviors was $4.09{\pm}.53$ for medical nurses and $4.13{\pm}.53$ for surgical nurses. 2) The total score for frequency was $3.15{\pm}.54$ for medical nurses and $3.24{\pm}.56$ for surgical nurses. 3) The perceived importance of nurse role behaviors was higher than the frequency, but the difference between two groups was not significant. 4) The perceived importance of nurse role behaviors was highly correlated with frequency (r=.579, p=.000) for the two groups. Conclusion: Medical and surgical nurses perceived the importance nurse role behavior but the frequency of the behavior is lower. Therefore, further research is needed to develop strategies to increase the frequency of nurse role behaviors.

• Journal of Korean Academy of Nursing
• /
• v.25 no.2
• /
• pp.351-361
• /
• 1995

The main purpose of the study is to identify critical risk factors for development of a family assessment tool to screen high risk family. This study used a conceptual framework of family diagnosis developed by Eui-sook Kim's (1993) and analyzed risk factors to identify the high risk family. As employing a explorative and methodological study design, this study has four stages. 1. In the first stage, 34 family risk factors were identified by doing intensive literature review on conceptual framework of family diagnoses. 2. In the second stage, above risk factors were tested for content validity by consultation with 29 persons in community health nursing, nursing education, family theory, and social work. 3. In the third stage, existing survey data was used for actual application of the identified risk factors. The survey data used for this purpose was previously collected for the community diagnosis in a region of Seoul. At the final stage, through the comparison between high risk and low risk families, initially identified 34 risk factors decreased to 25 risk factors. Among 34 risk factors, six factors did not agree with content of questionnaries sand two factors were not significant in differentiating the high risk family Also, two risk factors showed high correlation between themselves, so only one of those two factors was chosen. As a result, twenty-five risk factors chosen to identify the high risk family are following ; 1. A single parent family due to divorce or death of a partner, or unweded single mother 2. A family with an unrelated household members 3. A family with a working mother with a young child 4. A family with no regular income 5. A family with no rule in family or too strict rules 6. A family with little or no support from other lam-ily members 7. A family with little or no support from friends or relatives 8. A family with little or no time to share with each other 9. A family with family history of hypertension, diabetus, cancer 10. A family with a sick person 11. A family with a mentally ill person 12. A family with a disabled person 13. A family with an alcoholic person 14. A family with a excessive smoker who smokes more than 1 pack / day 15. A family with too much salt intake in their diet. 16. A family with inappropriate management skills for family health 17. A family with high utilization of drug store than hospital to solve the health problems of the family 18. A family with disharmony between husband and wife 19. A family with conflicts among the family members 20. A family with unequal division of labor among family members 21. An authoritative family structure 22. A socially isolated family 23. The location of house is not residential area 24. A family with high risk of accidents 25. The drinking water and sewage systems are not hygienic. The main implication of the results of this study is clinical use. The high risk factors can be used to identify the high risk family effectively and efficiently. The use of high risk factors woule contribute to develop a conceptual framework of family diagnosis in Korea and the list of risk factors need to be revised continuously. Further researches are needed to develop an index of weight of each risk factor and to validate the risk factors.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.24 no.1
• /
• pp.79-85
• /
• 2011

Bridge Weigh-in-Motion(BWIM) system calculates a travelling vehicle's weight without interruption of traffic flow by analyzing the signals that are acquired from various sensors installed in the bridge. BWIM system or data accumulated from the BWIM system can be utilized to development of updated live load model for highway bridge design, fatigue load model for estimation of remaining life of bridges, etc. Field test with moving trucks including various load cases should be performed to guarantee successful development of precise BWIM system. In this paper, a numerical simulation technique is adopted as an alternative or supplement to the vehicle traveling test that is indispensible but expensive in time and budget. The constructed numerical model is validated by comparison experimentally measured signal with numerically generated signal. Also vehicles with various dynamic characteristics and travelling conditions are considered in numerical simulation to investigate the variation of bridge responses. Considered parameters in the numerical study are vehicle velocity, natural frequency of the vehicle, height of entry bump, and lateral position of the vehicle. By analyzing the results, it is revealed that the lateral position and natural frequency of the vehicle should be considered to increase precision of developing BWIM system. Since generation of vehicle travelling signal by the numerical simulation technique costs much less than field test, a large number of test parameters can effectively be considered to validate the developed BWIM algorithm. Also, when artificial neural network technique is applied, voluminous data set required for training and testing of the neural network can be prepared by numerical generation. Consequently, proposed numerical simulation technique may contribute to improve precision and performance of BWIM systems.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.37 no.5
• /
• pp.94-104
• /
• 2000

The accuracy and reliability of the target tracking is very critical issue in the design of automotive collision warning radar A significant problem in multi-target tracking (MTT) is the target-to-measurement data association If an incorrect measurement is associated with a target, the target could diverge the track and be prematurely terminated or cause other targets to also diverge the track. Most methods for target-to-measurement data association tend to coalesce neighboring targets Therefore, many algorithms have been developed to solve this data association problem. In this paper, a new multi-target data association method based on order statistics is described The new approaches. called the order statistics probabilistic data association (OSPDA) and the order statistics joint probabilistic data association (OSJPDA), are formulated using the association probabilities of the probabilistic data association (PDA) and the joint probabilistic data association (JPDA) filters, respectively Using the decision logic. an optimal or near optimal target-to-measurement data association is made A computer simulation of the proposed method in a heavy cluttered condition is given, including a comparison With the nearest-neighbor CNN). the PDA, and the JPDA filters, Simulation results show that the performances of the OSPDA filter and the OSJPDA filter are superior to those of the PDA filter and the JPDA filter in terms of tracking accuracy about 18% and 19%, respectively In addition, the proposed method is implemented using a developed digital signal processing (DSP) board which can be interfaced with the engine control unit (ECU) of car engine and with the d?xer through the controller area network (CAN)

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.39 no.6
• /
• pp.691-702
• /
• 2019

Flood inundation map has various important roles in terms of municipal planning, timely dam operation, economic levee design, and building flood forecasting systems. Considering that the riparian areas adjacent to national rivers with high potential flood vulnerability conventionally imposed special cares to justify applications of recently available two- or three-dimensional flood inundation numerical models on top of digital elevation models of dense spatial resolution such as LiDAR irrespective of their high costs. On the contrary, local streams usually could not have benefits from recent technological advances, instead they inevitably have relied upon time-consuming manual drawings or have accepted DEMs with poor resolutions or inaccurate 1D numerical models for producing inundation maps due mainly to limited budgets and suitable techniques. In order to efficiently and cost-effectively provide a series of flood inundation maps dedicatedly for the local streams, this study proposed an OpenGIS-based flood mapping tool named Open Flood Mapper (OFM). The spatial accuracy of flood inundation map derived from the OFM was validated throughout comparison with an inundation trace map acquired after typhoon Nari in Hancheon basin located in Jeju Island. Also, a series of inundation maps from the OFM were comprehensively investigated to track the burst of flood in the extreme flood events.

• Resources Recycling
• /
• v.28 no.6
• /
• pp.26-35
• /
• 2019

This study aims to introduce and economical review on the possibilities of rare earth elements(REEs) recovery from coal ashes and the analysis of economical evaluation factors based on the data for securing domestic rare earth elements. The cut-off grade of REEs on recovering from coal ash was confirmed to be 1,000 ppm on total rare earth oxides(TREO) basis, and while the economic value of coal ash changed with contents and specific elements of rare earth elements. This shall be resulted in the price differences of rare earth elements required by the current industry, and it probably varies depending on the future demand of rare earth components. For developing of commercial recovery technology on REEs in coal ashes, many researches have been carried out by various analyzing methods, such as evaluation of holding value of REEs in ashes, assessment between supply and demand of industry, comparison of investment and its profitability for the REEs's production from coal ashes, and so on. Although these methods have been suggested, its recovery system with economical feasibility could not been confirmed up to present. In this reason, the process design of recovering REEs from coal ash shall be researched continuously to solve the problems of the global rare earth market. And also these researches shall be conducted actively in Korea for the purpose of securing the REEs resources and their recovering technologies.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.45 no.10
• /
• pp.844-854
• /
• 2017

The Expansion-Deflection(E-D) nozzle is a nozzle that has a performance gain through the altitude compensation effect by changing the effective area within the nozzle according to the altitude. An E-D nozzle has been known to reduce the length of the nozzle and achieve the payload gain of the launch vehicle. Due to the potential advantages of an E-D nozzle, related research has been carried out in the United Kingdom, Germany, Australia and Europe etc. In the UK, the flow characteristics of the E-D nozzle and the performance comparison with the dual-bell nozzle which is altitude compensation nozzle were studied. In order to understand the transition characteristics of the E-D nozzle in DLR, the transition characteristics according to the nozzle pressure ratio change were analyzed. In Europe, numerical study using the E-D nozzle concept on upper stage of the launch vehicle Ariane 5 ESC-B was carried out to confirm the possibility of payload gain according to the nozzle length reduction. In this paper, research trends of an E-D nozzle performed outside the country are classified and analyzed according to their characteristics and utilized as basic data of E-D nozzle research in the future.