• Title/Summary/Keyword: coefficient problems

Search Result 861, Processing Time 0.026 seconds

Improvement of COMS land surface temperature retrieval algorithm by considering diurnal variation of air temperature (기온의 일 변동을 고려한 COMS 지표면온도 산출 알고리즘 개선)

  • Choi, Youn-Young;Suh, Myoung-Seok
    • Korean Journal of Remote Sensing
    • /
    • v.32 no.5
    • /
    • pp.435-452
    • /
    • 2016
  • Land Surface Temperature (LST) has been operationally retrieved from the Communication, Ocean, and Meteorological Satellite (COMS) data by the spilt-window method (CSW_v2.0) developed by Cho et al. (2015). Although the CSW_v2.0 retrieved the LST with a reasonable quality compared to the Moderate Resolution Imaging Spectroradiometer (MODIS) LST data, it showed a relatively poor performance for the strong inversion and lapse rate conditions. To solve this problem, the LST retrieval algorithm (CSW_v2.0) was updated using the simulation results of radiative transfer model (MODTRAN 4.0) by considering the diurnal variations of air temperature. In general, the upgraded version, CSW_v3.0 showed a similar correlation coefficient between the prescribed LSTs and retrieved LSTs (0.99), the relatively smaller bias (from -0.03 K to-0.012 K) and the Root Mean Square Error (RMSE) (from 1.39 K to 1.138 K). Particularly, CSW_v3.0 improved the systematic problems of CSW_v2.0 that were encountered when temperature differences between LST and air temperature are very large and/or small (inversion layers and superadiabatic lapse rates), and when the brightness temperature differences and surface emissivity differences were large. The bias and RMSE of CSW_v2.0 were reduced by 10-30% in CSW_v3.0. The indirect validation results using the MODIS LST data showed that CSW_3.0 improved the retrieval accuracy of LST in terms of bias (from -0.629 K to -0.049 K) and RMSE (from 2.537 K to 2.502 K) compared to the CSW_v2.0.

Characteristics and Drug Release Profiles of Multilamellar Vesicle(MLV) and Microemulsified Liposome(MEL) Entrapped 5-Fluorouracil and Its derivatives (5-Fluorouracil과 그 유도체를 봉입한 Multilamellar Vesicle(MLV)과 Microemulsified Liposome(MEL)의 특성 및 약물방출 거동)

  • Jee, Ung-Kil;Park, Mok-Soon;Lee, Gye-Won;Lyu, Yeon-Geun
    • Journal of Pharmaceutical Investigation
    • /
    • v.25 no.3
    • /
    • pp.249-264
    • /
    • 1995
  • Although liposome has many advantages as a pharmaceutical dosage form, its application in the industrial field has been limited because of some problems such as preparation method, reproducibility, scale-up, stability and sterilization etc. Liposomes prepared by microemulsification method had defined size, narrow size distribution, reproducibility and high entrapment efficiency. For enhancing the stability, the dry form of liposome was recommended. These types of liposome are proliposome and freeze-dried liposome. The liposome must have some properties for preparing of freeze-dried liposome; small size $(50{\sim}200\;nm)$, narrow size distribution and cryoprotectant. In this experiment, the liposomes containing 5-Fluorouracil(5-FU) and its prodrug(pentyl-5-FU-1-acetate; PFA, hexyl-5-FU-1-acetate; HFA) were made with soybean phosphatidylcholine, cholesterol, stearylamine(SA) and dicetyl phosphate(DCP) employing hydration method or microemulsification method using $Microfluidizer^{TM}$. Both or liposome types were MLV and MEL. After preparation, freeze drying and rehydration were performed. In the process of freezing, trehalose(Tr) was added as a cryoprotectant. Their evaluation methods were as follows; entrapment efficiency, mean particle size and size distribution, dissolution test, retain of entrapment efficiency and turbidity after freeze-drying. The results are summarized as belows. The entrapment efficiency of 5-FU was dependent on total lipid concentration and cholesterol content but that of PFA and HFA was decreased when cholesterol was added. When DCP and SA were added, entrapment efficiency was decreased. As the partition coefficient of drug was increased, entrapment efficiency was increased. Under the same condition, entrapment efficiency of MEL is similar to that of MLV. The mean particle size and size distribution of MEL were smaller than those of MLV. Dissolution rates of drug from both liposome types were comparatively similar. Dissolution rates of drugs with serum and liver homogenate were faster than without these material. After preparation of liposome, free drug was removed efficiency by Dowex 50W-X4. When liposome was freeze-dried and then rehydrated in the presence of Tr, characteristics of liposome were maintained well in MEL than MLV. Tr Was used successfully as a cryoprotectant in the process of freeze drying and the optimal ratio of Tr:Lipid was 4:1(g/g).

  • PDF

Applicability Evaluation for Discharge Model Using Curve Number and Convolution Neural Network (Curve Number 및 Convolution Neural Network를 이용한 유출모형의 적용성 평가)

  • Song, Chul Min;Lee, Kwang Hyun
    • Ecology and Resilient Infrastructure
    • /
    • v.7 no.2
    • /
    • pp.114-125
    • /
    • 2020
  • Despite the various artificial neural networks that have been developed, most of the discharge models in previous studies have been developed using deep neural networks. This study aimed to develop a discharge model using a convolution neural network (CNN), which was used to solve classification problems. Furthermore, the applicability of CNN was evaluated. The photographs (pictures or images) for input data to CNN could not clearly show the characteristics of the study area as well as precipitation. Hence, the model employed in this study had to use numerical images. To solve the problem, the CN of NRCS was used to generate images as input data for the model. The generated images showed a good possibility of applicability as input data. Moreover, a new application of CN, which had been used only for discharge prediction, was proposed in this study. As a result of CNN training, the model was trained and generalized stably. Comparison between the actual and predicted values had an R2 of 0.79, which was relatively high. The model showed good performance in terms of the Pearson correlation coefficient (0.84), the Nash-Sutcliffe efficiency (NSE) (0.63), and the root mean square error (24.54 ㎥/s).

A study on Improvement and Invigoration of Cooperation Charge on Conservation Ecosystem Fund (생태계보전협력금 제도 활성화를 위한 부과금 개선 방안 연구)

  • Kim, Gyung-Ho;Lee, Sang-Houck
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.14 no.6
    • /
    • pp.97-109
    • /
    • 2011
  • Korea introduced the cooperation charge on conservation of ecosystem for minimizing damage of ecosystem due to development projects and their effects and for preparing resources for natural environment conservation projects. Advanced countries have made efforts by expanding investment in natural environment conservation and restoring projects to promote prevention of global warming and improvement of biological diversity, are establishing nationwide strategies and plans. To examine the reality of projects by returns of the cooperation charge on conservation of ecosystem, microsite projects in schools and public facilities take the largest share while their project budgets are only about 100~300 KRW, relatively small, which might be attributable to budget restrictions in accordance with the calculating method of levying cooperation charge on conservation of ecosystem and problems of project proceeding in the system of returning fund for projects in general. The conclusion which this study suggests on invigoration of cooperation charge on conservation of ecosystem and its operation are as followings. First, although the cooperation charge on conservation of ecosystem has been introduced in 2001, the amount of imposition per unit area remains unchanged. It is desirable to increase the amount into $1,400KRW/m^2$ as of August, 2011 as the price index has been continuously rising for the past 10 years and the upward adjustment of imposition per unit area should be notified by the decree of the Ministry of Environment every January. Second, the ceiling amount of the cooperation charge on conservation of ecosystem should be abolished. Now the ceiling amount is defined as 1 billion KRW but it was found that there was not any ceiling amount specified according to the comparative analysis of similar systems with the Korean environmental improvement fund. The ceiling should be abolished so that medium level businesses are carried out and ecosystem recovering projects in the true sense of the word can be made smoothly. Third, weight should be introduced in calculating amounts in accordance with ecologic and economic values. Harmony between development and environment can be achieved by applying differentiated weights of constant regional coefficient by use zone and ecologic and economic values. Continuous efforts of improving cooperation charge on conservation of ecosystem should be made more than anything else so that projects by returns of cooperation charge on conservation of ecosystem get effectiveness.

A study on the Improvement of Design Guideline for the Use Enhancement of Privately Owned Public Space (공개공지(公開空地) 효용성(效用性) 제고(提高)를 위한 설계지침(設計指針) 개선(改善) 방안(方案))

  • Park, Jung-Lim;Kim, Hyun-Jun;Kwon, Young-Hyoo
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.14 no.3
    • /
    • pp.115-141
    • /
    • 2011
  • In urban space, public space is publicly or privately owned space freely accessible by the public. Privately owned public space to the public hosts small-scale rest facilities to serve the public in buildings of certain purposes and sizes for the sake of pleasant urban environment. The Building Act and building ordinances formulate a set of criteria for management and easement of construction standards as well as the area. When creating privately owned public space, one can get incentives through the easement of floor space index and height limit. The purposes of this study were to investigate and analyze privately owned public open space, which is freely accessible by the public, and its adjacent streets and to propose plans to improve the regulations for securing privately owned public space for more rational and practical legal applications. The study then proposed some plans to help to increase the quality of privately owned public space including applying the coefficient to suggest the type of privately owned public space fit for the features of the streets and measure the appropriate utility level differently and distinguishing the mandatory items according to the facility regulations in privately owned public space from the ones qualified for additional points in case of installation. The types of privately owned public open space should be applied differently and the content of facilities intended should be different according to whether it will serve as a resting place or grant more importance on traffic by walking, depending on the features of its adjacent streets. The privately owned public space, the frontage space of building, and the adjacent sidewalks should become a whole and be regarded as one space from the integrated perspective. The results of the study claim further significance in that it investigated privately owned open space and roadside across Seoul. They will serve as useful data to solve the problems with the privately owned public space of the city, which destroys spatial continuity by focusing on the quantitative increase of privately owned open space and creating individual privately owned open spaces and builds high-rise buildings alienated from the existing spaces, and to increase the quality of future privately owned public space.

The Effect of Self-esteem on Resilience and the Mediating Effect of School Satisfaction : A First Year Female Students in High School (자아존중감이 적응유연성에 미치는 영향과 학교생활만족도의 매개효과 : 고등학교 1학년 여학생을 대상으로)

  • Weon, Heewook;Lim, Jiyoung;Son, Hae Kyoung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.4
    • /
    • pp.2684-2690
    • /
    • 2015
  • This study aims to identify the mediating effect of school satisfaction in the effect of self-esteem on resilience, and to examine the relationship between brain function quotient and resilience. In this descriptive study, questionnaires and brainwaves were collected from 145 female high school students in Seoul from November 22 to December 23, 2012. Data were analyzed by Pearson's correlation coefficient and three-step mediated regression analysis using SPSS 21.0. Among brain function quotients, stress resistance quotient were highly correlated with resilience, and both attention and brain quotient were significantly correlated with resilience. Moreover, school satisfaction showed the mediating effect in the effect of self-esteem on resilience. The findings suggest that brain function quotient, in specific, stress resistance quotient, should be considered in studies regarding resilience. Furthermore, predictor variables of resilience such as self-esteem and school satisfaction should be considered for preventive and therapeutic intervention to reduce various maladaptive problems in adolescents.

Estimation of Inbreeding Coefficients and Effective Population Size in Breeding Bulls of Hanwoo (Korean Cattle) (한우 씨수소의 근교계수와 유효집단크기의 추정)

  • Dang, Chang-Gwon;Lee, Jung-Jae;Kim, Nae-Soo
    • Journal of Animal Science and Technology
    • /
    • v.53 no.4
    • /
    • pp.297-302
    • /
    • 2011
  • This study was carried out to estimate average inbreeding coefficients, relatedness and effective population size of breeding bulls and to suggest optimal alternatives on problems of current Hanwoo improvement system. Data on proven and young bulls were obtained from 1,128 heads of Livestock Improvement Main Center from 1983 to 2008. Pedigree information on proven and young bulls was obtained from 3,760 heads of Korea Animal Improvement Association. Average inbreeding coefficients and average relatedness of proven and young bulls were estimated at the range of 0.04-0.07%, 0.10-6.82%, respectively. Effective population size was estimated for 220 heads from the average rate of inbreeding of last 26 years. Average inbreeding coefficient is rising rapidly for the last two years as well as average relatedness. Effective population size was estimated for 47 heads for the last five years. These results suggest that selection criteria of proven bulls should include not only genetic evaluation of carcass performance from progeny-test, but also inbreeding and relationship coefficients, in order to maintain genetic variability of Hanwoo. In addition, effective population size should be increased by increasing the number of proven bulls.

The sexual knowledge, sexual attitude and sexual behavior of psychiatric patients (정신질환자의 성지식, 성태도 및 성행동)

  • Park, Seung-Mi;Kim, Ji-Young;Ko, Sung-Hee
    • Journal of Digital Convergence
    • /
    • v.15 no.9
    • /
    • pp.261-271
    • /
    • 2017
  • This study was conducted to identify sexual knowledge, sexual attitude, and sexual behavior that are perceived by psychiatric patients, and analyzes their differences and relations. Participants were 222 adult psychiatric patients hospitalized in two psychiatric hospitals located at K city of J province. Data were collected from March 11 to April 15, 2016 by using structured questionnaires. Collected data were analyzed through independent t-test, One-way ANOVA, $Scheff{\acute{e}}$ test, Pearson's Correlation Coefficients using SPSS/WIN 20.0 program. The mean score of sexual knowledge was 2.60, sexual attitude was 2.74, and sexual behavior was 0.49. The sexual knowledge of patients differed significantly according to parent attitude(${\rho}$<.01), and sexual behavior showed the difference according to diagnosis(${\rho}$<.05). Sexual knowledge had a significant positive correlation with sexual attitude(r=.75, ${\rho}$<.001) and sexual behavior(r=.15, ${\rho}$<.05). There were also positive correlation between the sexual attitude and active sexual behaviour(r=.20, ${\rho}$<.01), the subcategory of sexual behaviour. These results of study suggest that psychiatric nurses should appropriately assess sexual problems of psychiatric patients and include them in nursing interventions.

Comparison of Flow Characteristics for the Development of a C-Type Strainer with Its Inlet and Outlet on a Straight Line (유입·유출구가 일직선상인 C형 스트레이너 개발을 위한 유동특성 비교)

  • Shin, Byung-kyun;Kwon, Chang-Hee
    • Journal of Digital Convergence
    • /
    • v.14 no.11
    • /
    • pp.257-265
    • /
    • 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.

A Hydrometeorological Time Series Analysis of Geum River Watershed with GIS Data Considering Climate Change (기후변화를 고려한 GIS 자료 기반의 금강유역 수문기상시계열 특성 분석)

  • Park, Jin-Hyeog;Lee, Geun-Sang;Yang, Jeong-Seok;Kim, Sea-Won
    • Spatial Information Research
    • /
    • v.20 no.3
    • /
    • pp.39-50
    • /
    • 2012
  • The objective of this study is the quantitative analysis of climate change effects by performing several statistical analyses with hydrometeorological data sets for past 30 years in Geum river watershed. Temperature, precipitation, relative humidity data sets were collected from eight observation stations for 37 years(1973~2009) in Geum river watershed. River level data was collected from Gongju and Gyuam gauge stations for 36 years(1973~2008) considering rating curve credibility problems and future long-term runoff modeling. Annual and seasonal year-to-year variation of hydrometeorological components were analyzed by calculating the average, standard deviation, skewness, and coefficient of variation. The results show precipitation has the strongest variability. Run test, Turning point test, and Anderson Exact test were performed to check if there is randomness in the data sets. Temperature and precipitation data have randomness and relative humidity and river level data have regularity. Groundwater level data has both aspects(randomness and regularity). Linear regression and Mann-Kendal test were performed for trend test. Temperature is increasing yearly and seasonally and precipitation is increasing in summer. Relative humidity is obviously decreasing. The results of this study can be used for the evaluation of the effects of climate change on water resources and the establishment of future water resources management technique development plan.