• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.739-744
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• 2017

Elastic deformation and fatigue damage can cause the permanent deformation of a kart's frame during turning, affecting the kart's driving performance. A kart's frame does not contain any suspension or differential devices and, therefore, the dynamic behavior caused by torsional deformation when driving along a curve can strongly affect these two kinds of deformations. To analyze the dynamic behavior of a kart along a curved section, the GPS trajectory of the kart is obtained and the torsional stress acting on the kart-frame is measured in real time. The mechanical properties of leisure and racing karts are investigated by analyzing their material properties and conducting a tensile test. The torsional stress concentration and frame distortion are investigated through a stress analysis of the frame on the basis of the obtained results. Leisure and racing karts are tested in each driving condition using driving analysis equipment. The behavior of a kart when being driven along a curved section is investigated through this test. Because load movement occurs owing to centrifugal force when driving along a curve, torsional stress acts on the kart's steel frame. In the case of a leisure kart, the maximum torsional stress derived from the torsional fatigue limit was found to be 230 MPa, and the torsional fatigue limit coefficient was 0.65 when driving at a speed of 40 km/h. Furthermore, the driving elements during the cornering of a kart were measured based on an actual auto-test after installing a driving measurement system, and the driving behavior of the kart was analyzed by measuring its vertical displacement.

• Journal of Digital Convergence
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• v.14 no.11
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• pp.257-265
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• 2016

The purpose of this study was to develop a strainer that could protect a flow system by blocking the introduction of foreign substances into the pipe of industrial or architectural facilities. Strainers are installed at the front tip of valves, machines, or pumps in the piping line of clean water, oil, or gas. There are Y-type, U-type, and T-type strainers. The study identified problems with the Y-type strainers, develop a "C-type strainer with its inlet and outlet on a straight line" as a more improved new model, and compared them in functions in a full-scale strainer test. The study conducted a full-scale strainer test according to four situations at the flow laboratory of Korea Research Institute of Standards and Science by using the old Y-type strainer and C-type strainer 50A. The test results show that the C-type strainer had a higher capacity coefficient(Kv) than the Y-type one, recording 74.9% when there was no screen, 54.5% when there were no foreign substances in the screen, 54.2% when there was a 15% accumulation of foreign substances, and 52.4% when there was a 30% accumulation of foreign substances. The investigator conducted a test only with the 50A type due to the limitations of life-size strainers, but the results demonstrate that the C-type strainer had better flow characteristics than the Y-type one.

• Korean Journal of Remote Sensing
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• v.37 no.5_2
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• pp.1307-1315
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• 2021

The Changjiang Diluted Water (CDW) spreads over the East China Sea every summer and significantly affects the sea surface salinity changes in the seas around Jeju Island and the southern coast of Korea peninsula. Sometimes its effect extends to the eastern coast of Korea peninsula through the Korea Strait. Specifically, the CDW has a significant impact on marine physics and ecology and causes damage to fisheries and aquaculture. However, due to the limited field surveys, continuous observation of the CDW in the East China Sea is practically difficult. Many studies have been conducted using satellite measurements to monitor CDW distribution in near-real time. In this study, an algorithm for estimating Sea Surface Salinity (SSS) in the East China Sea was developed using the Geostationary Ocean Color Imager (GOCI). The Multilayer Perceptron Neural Network (MPNN) method was employed for developing an algorithm, and Soil Moisture Active Passive (SMAP) SSS data was selected for the output. In the previous study, an algorithm for estimating SSS using GOCI was trained by 2016 observation data. By comparison, the train data period was extended from 2015 to 2020 to improve the algorithm performance. The validation results with the National Institute of Fisheries Science (NIFS) serial oceanographic observation data from 2011 to 2019 show 0.61 of coefficient of determination (R²) and 1.08 psu of Root Mean Square Errors (RMSE). This study was carried out to develop an algorithm for monitoring the surface salinity of the East China Sea using GOCI and is expected to contribute to the development of the algorithm for estimating SSS by using GOCI-II.

• Journal of Climate Change Research
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• v.2 no.2
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• pp.79-91
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• 2011

In order to study interactions between climate change and air quality, a modeling system including the downscaling scheme has been developed in the integrated manner. This research focuses on the development of a downscaling method to utilize CCSM3 outputs as the initial and boundary conditions for the regional climate model, MM5. Horizontal/vertical interpolation was performed to convert from the latitude/longitude and hybrid-vertical coordinate for the CCSM3 model to the Lambert-Conformal Arakawa-B and sigma-vertical coordinate for the MM5 model. A variable diagnosis was made to link between different variables and their units of CCSM and MM5. To evaluate the dynamic downscaling performance of this study, spatial distributions were compared between outputs of CCSM/MM5 and NRA/MM5 and statistic analysis was conducted. Temperature and precipitation patterns of CCSM/MM5 in summer and winter showed a similar pattern with those of observation data in East Asia and the Korean Peninsula. In addition, statistical analysis presented that the agreement index (AI) is more than 0.9 and correlation coefficient about 0.9. Those results indicate that the dynamic downscaling system built in this study can be used for the research of interaction between climate change and air quality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.355-362
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• 2016

The pipe material is selected according to the physical and chemical properties of the fluid flowing within it. Because the fluid used in fire extinguish systems is water, the various foreign substances dissolved in it cause scale to form on the pipe wall and accelerate the corrosion and aging of the pipe itself. This results in an increase in the friction loss and eventually degrades the efficiency of the pump. The use of CPVC (Chlorinated Poly-Vinyl Chloride) pipes was confirmed to reduce the friction loss compared to conventional steel pipes in the design and construction stages. The friction loss was found to be 76.64MPa with a C-value of 120 for the steel pipe and 50.72 MPa with a C-value of 150 for the CPVC pipe in an actual apartment construction environment. It was confirmed that the friction loss was improved by about 34% when using the CPVC pipe. When the steel and CPVC pipes were employed in the construction, the construction costs were 1,585,158 and 931,842 won, respectively. Therefore, it was shown that the construction cost was reduced by about 41%. We investigated the safety of the fire extinguishing system and the improvement in the economic performance due to the reduction in the total installed capacity by studying practical applications in the field.

• Journal of the Korean Magnetics Society
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• v.20 no.1
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• pp.18-23
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• 2010

Ferromagnetic resonance (FMR) measurement is an important experimental technique for the study of magnetic dynamics. We designed and set up the vector network analyzer ferromagnetic resonance (VNA-FMR) measurement system with home made coplanar waveguides (CPW). We examined 10-, 20-, 40-nm thick Py thin films to test the performance of the VNA-FMR measurement system. We measured S-parameter (transmission/reflection coefficient) of Py thin films on a CPW. Resonance frequency is investigated from 2.5 to 7 GHz for a field range from 0 to 490 Oe. The VNA-FMR data shows the resonance frequency increment when the external magnetic field increases. We also investigated Gilbert damping constant of Py thin film using resonance frequency (${\omega}_r$) and linewidth ($\Delta\omega$). After investigating dependence of thickness, we find that an decrease in S-parameter intensity as Py thin film thickness decreases. And the FMR results show that the effective saturation magnetization, $M_{eff}$, increase from 7.205($\pm$0.013) kOe to 7.840($\pm$0.014) kOe, while the film thickness varies from 10 to 40 nm.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.423-435
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• 2013

The Codonopsis pilosula is traditional oriental herb associated with immune-modulatory functions and has anti-inflammatory properties and antioxidative activity. The present study was conducted to investigate the effects of dietary supplementation of Codonopsis pilosula extract powder (CEP) on the immunity and productivity in sows and piglets. A total of 20 pregnant sows were randomly assigned to two dietary treatments, which was given a corn-soybean meal diet with 0% and 0.5% CEP from 40 days prepartum to weaning (25 days postpartum). The immune system of piglets was expected to build up, because the feeding of CEP might increase the colostrum contents in sows. We also predicted that the growth performance of piglets also could be increased by some compensation effects due to the increased immunity of piglets. In results, immunities of sows and piglets as well as growth performance of piglets were not affected by the supplementation of CEP. The correlation between the colostrum and the serum on the IgG contents tended to have a positive correlation, although there was no significant (coefficient, 0.435; P=0.102). This result suggests that the supplementation of CEP may increase IgG contents in sows and piglets and contribute to improve immunity of piglets. In conclusion, it is thought that the physiologically active substances of CEP did not influence to the immune synergic effects in vivo of sows. Thus, the metabolic and action mechanism of the physiologically active substances of CEP should be explored to evaluate the availability of CEP as a feed additive for the immunomodulator.

• Research in Community and Public Health Nursing
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• v.1 no.1
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• pp.465-502
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• 1989

The purpose of this study was to find out the general characteristics of school health teachers, the status of school health resources and the degrees of self-confident performance for the 124 school health teachers in Pusan City. Data was collected by means of questionaires from Aug. 1986 to Mar. 1987. The data were analyzed by use of percentage, mean, standard deviation, t-test, ANOVA and Pearson-correlation coefficient. The results of this study were as follows: 1 . General Characteristics of School Health Teachers (SHT) 1) The average of age of the SHT was 32.8 years old and 39.5% of them were from 30 to 34 years old. 2) The average for school nursing experience of the SHT was 7.9 years and 37.9% of them were from 5 to 9 years. 3) The 45.2% of them have not the clinical experience. 4) The 74.2% of them were graduated from the 3 years college of nursing. 2. Status of school health resources and nursing activities. 1) The average of student number was 2497.3 and class number was 45.2. 2) The average of school health budget was 1039000 won and 27.7% of school health budget expended on examination cost. 3) Only 29.0% of all schools have organization for school health. 4) The 84.7% of all schools have health clinic separately and 69.1% of schools have less than $33m^2$ sized. 5) The average of clinic visitor number was 2111.8 for 1 year. 6) Major problem was on digestive system. And other problems were skin, respiratory, musculo-skeletal system and dental problem. 7) The number of literal message was 14.4 times for 1 year. 3. The degree of the school health teachers' self-confidence. The school health teachers' self-confidence was deviced into 6 and the maximum degree was 4. 1) Program planning & evaluation; 2.8 2) Clinic management; 2.9 3) Health education, 3.0 4) Management of school environment; 2.7 5) Health care services; 2.7 6) Operating of school health organization; 2.4 4. Significances to the degree of self-confidence on school health nursing activities. 1) There was significant difference between clinical management and Religion (t=2.15 p<.05) 2) There was significant difference between Operating of school health organization and level of school (F=3.588 p<.05) 3) Program planning & evaluation: expending time for clinical management (r=-0.184 p<.05) expending time for health care services (r=0.273 p<.01) 4) Clinical management: use of separate health clinic (r=0.151 p<.05) 5) Health education: use of separate health clinic (r=0.170 p<0.5) 6) Health care services: No. of student (r=-0.144 p<0.5) No. of class (r=-0.160 p<.05) 5. The degree of the school health teachers' self-discipline. The school health teachers' self-discipline was devided into 2 and the maximum degree was 2. 1) Program planning & evaluation:1.8 2) Clinic management: 1.9 3) Health education: 1.9 4) Management of school environment: 1.7 5) Health care services: 1.8 6) Operating of school health organization.: 1.3 6. Significances to the degree of self-discipline on school health nursing activities 1) Program planning & evaluation; Level of nursing education (F=4.309 p<.01) 2) Clinical management: Level of nursing education (F=3.587 p<.05) 3) Operating of school health organization: School health organization (t=-2.68 p<.01) 4) Health care services: School health organization (t=2,58 p<.05) 5) School health performance: School health organization (t=2.32 p<.05) 6) Program planning & evaluation: School health experience (r=0.239 p<.01) Expending time for program planning & evaluation (r=-0.172 p<.05) 7) Clinic management: School health experience (r=0.249 p<.01) Expending time for dinic management (r=0.181 p<.05) No. of student (r=-0.158 p<.05) Expending time of program planning & evaluation (r=-0.199 p<0.5) 8) Health education: School health experience (r=0.234 p<0.1) Expending time of program planning & evaluation (r=-0.193 p<.05) 9) Management of school environment: Age of school health teacher (r=0.142 p<.05) School health experience (r=0.255 p<.01) 10) Operating of school health organization: Medicine Purchase (r=-0.163 p<.05) 11) Health care services: School health experience (r=0.148 p<.05) Medicine purchase (r=-0.229 p<.01) 12) Total school health performance: School health experience (r=0.200 p<.05) Medicine purchase(r=-0.168 p<.05) Based on the above results, the suggestions are as follows: 1) As the SHT take charge of the reasonable number of student, the students will have benefit of the good health service in quality. 2) It is recommended to use the health clinic separately and to arrange adequate place for good school health service. 3) It is necessary that the SHT participate budget for school health. 4) It is required to enhance self-confidence on school health nursing activities through continuous educational programs.

• Korean Journal of Remote Sensing
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• v.37 no.2
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• pp.337-357
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• 2021

Because the growth of paddy rice is affected by meteorological factors, the selection of appropriate meteorological variables is essential to build a rice yield prediction model. This paper examines the suitability of multiple meteorological datasets for the rice yield modeling in South Korea, 1996-2019, and a hindcast experiment for rice yield using a machine learning method by considering the nonlinear relationships between meteorological variables and the rice yield. In addition to the ASOS in-situ observations, we used CRU-JRA ver. 2.1 and ERA5 reanalysis. From the multiple meteorological datasets, we extracted the four common variables (air temperature, relative humidity, solar radiation, and precipitation) and analyzed the characteristics of each data and the associations with rice yields. CRU-JRA ver. 2.1 showed an overall agreement with the other datasets. While relative humidity had a rare relationship with rice yields, solar radiation showed a somewhat high correlation with rice yields. Using the air temperature, solar radiation, and precipitation of July, August, and September, we built a random forest model for the hindcast experiments of rice yields. The model with CRU-JRA ver. 2.1 showed the best performance with a correlation coefficient of 0.772. The solar radiation in the prediction model had the most significant importance among the variables, which is in accordance with the generic agricultural knowledge. This paper has an implication for selecting from multiple meteorological datasets for rice yield modeling.

• Journal of Korean Public Health Nursing
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• v.4 no.1
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• pp.37-55
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• 1990

Every country in the world has been trying to expand the basic health right for the peoples as W.H.O has established the goal 'health for AU' by the year of 2000. Related to this goal, our government authority has establish the policy 'the insurance of health for all' into effect from July 198\). Recently hospitalshave been making a ceaseless effort for the plan for the rationalization of its management the academic World is making it a subject of discussion by doing the secure of manpower at a resonable level and the increase of productivity by the manpower. As a result of the efforts the study was established to secure the numbers of nursing manpower at a resonable level and use the unskilled persons at the utilizing field and seek the possible area of their activity for more efficient service through the investigation of ablity of simple nursing activities of regiestered nurses and nurse aides for rational function according to the educational levels and talents. The method of study was established by the registered nurses and nurse and nurse aides(R.N 229, N.A 226) who are working in 15 hospitals with over 200 beds. This surrey was conducted from Mar 29, 1989 to April 8, 1989. The method to test the degree of importance, difficulties, and the abillity of performance of a simple nursing activities was classified into 35 activities on the basis of references on this field. The degree of importance was composed from point l(Not so important) to 5(Very important). the degree of difficulties. was composed as follows; very easy - Point 1 very difficult and complicated - Point 5. and the ability of performance was composed from point 1 to 5. The materials gathered through the survey were analyzed with frequency, mean standard deviation, percentage. t-test, Anova, pearson's coefficient of correlation, stepwise multiple regression. factor analysis, discriminant analysis. The obtained results are summarized as follows: 1. The recognition values of the simple nursing activities of each group of registered nurse and nurse aides show; The degree of importance; 4.04 and 4.26 The degree of difficulties; 2.72 and 2.94 The ability of performance; 2.07 and 2.38 The brief summary shows there are little differences between who two groups the simple nursing activities turned out to be easy and simple work. 2. Regardless of the degree of importance, and difficulties, the ability of performance the important in fluencing of the degree of the simple nursing activities between the registered nurses and nurse aides was the order of educational level, hospital career, working career in wards and ages of the registered nurses and ages and hospital creer of nurse aides. The result was that the simple nursing activities could easily be familiar through the training of their working environment and period of experience. 3. Among the 35 simple nursing activities the items capable of resonable entrusting to the nurse aides are 5 that is helping bed-bathing, 8itz Bath, using bed pan, care while delivering patient, accompaying patient when visitor's check. There wasn't and differences between RN and nurse aides in performing the above 5 items. In anywhere. so we can say obviosuly that this nursing activities should be performed under the nursing system of which chief of nurse are supposed to supervise nurse aides as a possible function to be entrusted. In view of the above mentioned results, therefore, this partial functional job of the simple nursing activities can able be entrusted to the nurse aides through the regular training course. In case of these functional activities could be entrusted under, the responsibility of registered nurse, we can able suggest to for that there are the following advantages: 1.. In the nursing activities-affairs, the qualified guarantee of the nursing services can be kept and increased or promotoed with accommodation of the required nursing service and roles being expanded presently. 2. In the productivity of the hospital manpower, therefore, we have comt to view and consider in favourly that when an automational administration times would be come in the near future time to hospital affairs as a reality, to utilize the existing nures aides is better rather than investing so as to develop the other source manpowers or seek its for the efficient business management in the operational strategy or its policy.