• 제목/요약/키워드: $C^2-continuity$

검색결과 104건 처리시간 0.022초

위탁영농회사의 사업실태 및 경영성과 분석 (An Analysis of Business Management in the Farming Service Company)

  • 강창용;위용석;박현태
    • Journal of Biosystems Engineering
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    • 제19권4호
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    • pp.318-328
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    • 1994
  • This study was carried out to find out the possibility of continuity of the Farming Service Company (FSC), which has been founding since 1991 by the public administration to obtain the scale economy in the rice production, through the only financial analysis of the FSC. The results obtained were as follows. 1. The FSC's business is forward to the off-farm business rather than farm business. Based on the profit ratio, the profit ratio of off-farm business is more than that of farm business. It may cause the difficulty of policy to obtain the scale economy in the farming through the FSC. 2. Without subsidies the average net profit of the FSC was negative, which may provide the motives to the FSC to seek out the way to survive through the off-farm business, unless the FSC's could break up. 3. After all, the possibility of continuity of the FSC through the only financial analysis seems to be very little. Therefore the public administration should reconsider the present policy which is to found the more FSC continuously. If government wants to support the FSC continuously, government should focus on the conglomeration of farm land to increase the productivity of farming and on the subsidy of off-farm business to increase the profit ratio of the FSC.

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Quality Assessment of GPS L2C Signals and Measurements

  • Yun, Seonghyeon;Lee, Hungkyu
    • Journal of Positioning, Navigation, and Timing
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    • 제10권1호
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    • pp.13-20
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    • 2021
  • A series of numerical experiments with measurements observed at continuously operating reference stations (CORS) of the international GNSS services (IGS) and the national geographical information institute of Korea (NGII) have been intensively carried out to evaluate the quality of pseudo-ranges and carrier-phases of GPS L2C signal obtained by various receiver types, benign and harsh operational environment. In this analysis, some quality measures, such as signal-to-noise ratio (SNR), the magnitude of multipath, and the number of cycle slips, the pseudo-range and carrier phase obtaining rate were computed and compared. The SNR analysis revealed an impressive result that the trend in the SNR of C/A and the L2C comparably depends upon type of receivers. The result of multipath analysis also showed clearly different tendency depending on the receiver types. The reason for this inconsistent tendency was seemed to be that the different multipath mitigation algorithm built-in each receiver. The number of L2C cycle slip was less than P2(Y), and L2C measurements obtaining rate was higher than that of P2(Y) in three receiver types. In the harsh observational environment, L2C quality was not only superior to P2(Y) in all aspects such as SNR, multipath magnitude, the number of cycle slips, and measurement obtaining rate, but also it could maintain a level of quality equivalent to C/A. According to the results of this analysis, it's expected that improved positioning performance like accuracy and continuity can be got through the use of L2C instead of existing P2(Y).

파손된 탱크의 기름 유출량 산정을 위한 2차원 입자법 시뮬레이션 (Prediction of Oil Amount Leaked from Damaged Tank Using 2-dimensional Particle Simulation)

  • 남정우;황성철;박종천
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2011년 춘계학술대회논문집
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    • pp.278-285
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    • 2011
  • In the present study, the numerical prediction of the oil amount leaked from the hole of a damaged tank is investigated using the improved MPS (Moving Particle Semi-implicit) method, which was originally proposed by Koshizuka and Oka (1996) for incompressible flow. The governing equations, which consist of the continuity and Navier-Stokes equations, are solved by Lagrangian moving particles, and all terms expressed by differential operators should be replaced by the particle interaction models based on a Kernel function. The simulation results are validated though the comparison with the analytic solution based on Torricelli's equilibrium relation. Furthermore, a series of numerical simulations under the various conditions are performed in order to estimate more accurately the initial amount of leaked oil.

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Comparison of Neural Network Techniques for Text Data Analysis

  • Kim, Munhee;Kang, Kee-Hoon
    • International Journal of Advanced Culture Technology
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    • 제8권2호
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    • pp.231-238
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    • 2020
  • Generally, sequential data refers to data having continuity. Text data, which is a representative type of unstructured data, is also sequential data in that it is necessary to know the meaning of the preceding word in order to know the meaning of the following word or context. So far, many techniques for analyzing sequential data such as text data have been proposed. In this paper, four methods of 1d-CNN, LSTM, BiLSTM, and C-LSTM are introduced, focusing on neural network techniques. In addition, by using this, IMDb movie review data was classified into two classes to compare the performance of the techniques in terms of accuracy and analysis time.

Extended Stratification of North American Ginseng Seed

  • Proctor, John T.A.;Stechyshyn-Nagasawa, Audra
    • Journal of Ginseng Research
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    • 제32권2호
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    • pp.155-160
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    • 2008
  • The North American ginseng (Panax quinquefolius L.) seed crop varies from year to year. The ability to hold stratified seed for a year would ensure continuity of seed supply and no interruption in production cycles. Seed drying and rehydration protocols at room temperature $(21{\pm}2^{\circ}C)$ were developed. These protocols and seed storage at 4 ${\pm}1^{\circ}C$ and 35%, or variable, relative humidity (RH) allowed the holding of stratified seed for one year and then establishment of the following five treatments in field plots: Trt.1 : dried 2005 stratified seed (seed harvested Fall 2004) held at $4^{\circ}C$ and at variable humidity; Trt.2 : 2006 stratified seed planted directly into the field; Trt.3 : 2005 stratified seed dried in October 2005 and held at $4^{\circ}C$ and 35% RH ; Trt.4 : 2005 stratified seed held in moist sand from October to December 2005 at room temperature $(21{\pm}2^{\circ}C)$ and then in December dried and held at $4^{\circ}C$ and 35 % RH; Trt.5 : 2005 stratified seed held in moist sand from October to December 2005 at room temperature and then in December dried and held at $-12^{\circ}C$ Seedling emergence was best in Trts. 2 and 4 with 67.3 and 65.1% respectively which is similar to the industry expected rate of 68% after regular stratification. Seedling growth was similar in Trts. 2 and 4 with root dry weights of 172 and 159 mg respectively in mid-August. Therefore, if holding stratified seed in August/September for one year is desired, the seed can be placed in moist sand until December and then dried and stored at $4^{\circ}C$ and 35% RH. These seed can be planted in the following August/September and will germinate and grow in the following year to give an acceptable crop.

ON CONSISTENCY OF SOME NONPARAMETRIC BAYES ESTIMATORS WITH RESPECT TO A BETA PROCESS BASED ON INCOMPLETE DATA

  • Hong, Jee-Chang;Jung, In-Ha
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제5권2호
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    • pp.123-132
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    • 1998
  • Let F and G denote the distribution functions of the failure times and the censoring variables in a random censorship model. Susarla and Van Ryzin(1978) verified consistency of $F_{\alpha}$, he NPBE of F with respect to the Dirichlet process prior D($\alpha$), in which they assumed F and G are continuous. Assuming that A, the cumulative hazard function, is distributed according to a beta process with parameters c, $\alpha$, Hjort(1990) obtained the Bayes estimator $A_{c,\alpha}$ of A under a squared error loss function. By the theory of product-integral developed by Gill and Johansen(1990), the Bayes estimator $F_{c,\alpha}$ is recovered from $A_{c,\alpha}$. Continuity assumption on F and G is removed in our proof of the consistency of $A_{c,\alpha}$ and $F_{c,\alpha}$. Our result extends Susarla and Van Ryzin(1978) since a particular transform of a beta process is a Dirichlet process and the class of beta processes forms a much larger class than the class of Dirichlet processes.

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노즐용삭을 고려한 SF6 가스차단기 노즐의 열적회복특성 해석 (Analysis of Thermal Recovery Characteristics for Nozzle of SF6 GCB Considering Nozzle Ablation)

  • 이병윤;송기동;정진교;박경엽
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제54권2호
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    • pp.76-82
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    • 2005
  • In this paper, a method for analyzing the thermal recovery characteristics of the nozzle of gas circuit breaker was described. In order to obtain thermal recovery characteristics, the transient simulation of SF6 arc plasma within the nozzle was carried out. In particular, the nozzle ablation was taken into account by simultaneously solving the PTFE concentration equation with the governing equations such as continuity, momentum and energy equation. After that, post arc current calculation was performed with the rate of rise of recovery voltage changed. From the calculated post arc current, it was possible to suggest the thermal recovery characteristics of the nozzle of gas circuit breaker.

계층 요소 사용에 대한 연구 (A Study on the Use of Hierarchical Elements)

  • 김진환
    • 동력기계공학회지
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    • 제4권1호
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    • pp.68-73
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    • 2000
  • A mixed degree finite element solutions using hierarchical elements are investigated for convergences on a 2-D simple cases. Elements are generated block by block and each block is assigned an arbitrary solution degree. The numerical study showed that a well constructed blocks can increase the convergence and accuracy of finite element solutions. Also, it has been found that for higher order elements, the convergence trends can be deteriorated for smaller mesh sizes. A procedure for a variable fixed boundary condition has been included.

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Effect of Passivation on the Sintering Behavior of Submicron Nickel Powder Compacts for MLCC Application

  • Jo, Gi-Young;Lee, Kwi-Jong;Kang, Suk-Joong L.
    • 한국분말재료학회지
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    • 제20권6호
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    • pp.405-410
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    • 2013
  • During sintering of Ni-electrode multi-layer ceramic capacitors (MLCCs), the Ni electrode often becomes discontinuous because of its lower sintering temperature relative to that of $BaTiO_3$. In an attempt to retard the sintering of Ni, we introduced passivation of the Ni powder. To find the optimal passivation conditions, a thermogravimetric analysis (TGA) was conducted in air. After passivation at $250^{\circ}C$ for 11 h in air, a nickel oxide shell with a thickness of 4-5 nm was formed on nickel nanoparticles of 180 nm size. As anticipated, densification of the compacts of the passivated Ni/NiO core-shell powder was retarded: the starting temperature of densification increased from ${\sim}400^{\circ}C$ to ${\sim}600^{\circ}C$ in a $97N_2-3H_2$ (vol %) atmosphere. Grain growth was also retarded during sintering at temperatures of 750 and $1000^{\circ}C$. When the sintering atmosphere was changed from wet $99.93N_2-0.07H_2$ to wet $99.98N_2-0.02H_2$, the average grain size decreased at the same sintering temperature. The conductivity of the passivated powder sample sintered at $1150^{\circ}C$ for 8 h in wet $99.93N_2-0.07H_2$ was measured to be $3.9{\times}10^4S/cm$, which is comparable with that, $4.6{\times}10^4S/cm$, of the Ni powder compact without passivation. These results demonstrate that passivation of Ni is a viable means of retarding sintering of a Ni electrode and hence improving its continuity in the fabrication of $BaTiO_3$-based multi-layer ceramic capacitors.

PSEUDO n-JORDAN HOMOMORPHISMS AND PSEUDO n-HOMOMORPHISMS ON BANACH ALGEBRAS

  • Ebadian, Ali;Gordji, Madjid Eshaghi;Jabbari, Ali
    • 호남수학학술지
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    • 제42권2호
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    • pp.411-423
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    • 2020
  • In this paper, we correct some errors and typos of [2] and introduce a new concept related to pseudo n-Jordan homomorphisms, that we call it pseudo n-homomorphism. We investigate automatic continuity and positivity of pseudo n-homomorphisms and pseudo n-Jordan homomorphisms on Banach algebras and C*-algebras. Moreover, we show that the sum of two pseudo n-Jordan homomorphisms is not a pseudo n-Jordan homomorphism and we show that under some conditions the sum of two pseudo n-Jordan homomorphisms is a pseudo n-Jordan homomorphism.