• Title/Summary/Keyword: intrinsic mean

Search Result 163, Processing Time 0.024 seconds

Temperature-dependent Fecundity and Life Table Parameters of Aphis gossypii Glover (Homoptera: Aphididae) on Cucumber Plants (오이에서 온도에 따른 목화진딧물 산자수 및 생명표)

  • Kim Ji-Soo;Kim Tae-Heung
    • Korean journal of applied entomology
    • /
    • v.43 no.3 s.136
    • /
    • pp.211-215
    • /
    • 2004
  • Temperature-fecundity of the melon aphid, Aphis gossypii Glover, was studied at constant temperatures ranging from 15 to $32.5^{\circ}C$ under $60-70\%$ RH and a photoperiod of 16 : 8 (L : D) A life table parameters were constructed using the results. The longevity of A. gossypii gradually increased with decreasing temperature below $27.5^{\circ}C$. Also fecundity increased with decreasing temperature and the highest fecundity was 61.8 nymphs per female at $17.5^{\circ}C$. However. daily fecundity increased with increasing temperatures up to $22.5^{\circ}C$ showing 5.9 nymphs per day and thereafter decreased. Longevity and fecundity of the adult in the greenhouse with an average temperature of $21^{\circ}C$ and $65.6\%$ RH, were 20.0 days and 59.6, respectively, which were longer and higher than those in the growth chamber with similar conditions. net reproductive rate (Ro) was 54.9 at $17.5^{\circ}C$ while intrinsic rate of increase ($r_m$) and finite rate of increase ($\lambda$) were the highest 0.5 and 1.6 at $30^{\circ}C$, respectively. doubling time (DT) and mean generation time (T) were the shortest 1.4 and 6.8 at $30^{\circ}C$ indicating that optimal temperature for the development is $30^{\circ}C$.

Analysis on Reactions of Full-Scale Airframe Static Structural Test (항공기 전기체 정적구조시험의 반력 분석)

  • Shim, Jae-yeul
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.48 no.3
    • /
    • pp.195-205
    • /
    • 2020
  • This study addresses analysis on reactions which are induced in restraint system for airframe full-scale static structural test. This system restraints 6 degrees of freedom of a test article. It is valuable to study evaluating test error through analysis on the reactions which include all errors in a test. It is required to calculate fistly right reactions for the evaluation. This study focuses on calculation of the right reactions. The reaction is represented by sum of nominal reaction(Rn) and testing error reactions(Rce, Rerr) and is analyzed by two steps (inital vs relative reaction) in this study. It would evaluate intrinsic error at 0%DLL and error induced from applying test load, separately. Based on analysis using test data of a full-scale static test(canard type aircraft), resultant force of Rces and Rce_rs are distributed within 82.8N while resultant force of Rerr_rs shows to increase upto max. 808N as load level increment. Such well distribution of the Rce within the small range is caused from TMF values characteristics which are well distributed within -30N~40N. Additionally, it is shown through qualitative analysis on three components(X0, Y0, Z0) of the relative reaction(Rerr_r) that the reactions must be calculated with considering deformation of test article to calculate correctly reactions. This study shows also that equations characterizing deformation of components of test article are required to calculate the correct reactions, the equations must include information which will be used to calculate movement of all loading points.

Adaptation of Anisopteromalus calandrae (Hymenoptera: Pteromalidae) to an alternative host, Callosobruchus chinensis (Coleoptera: Bruchidae) (Anisopteromalus calandrae (Hymenoptera: Pteromalidae)의 대체기주 팥구미(Callosobruchus chinensis (L.))에 대한 적응)

  • Kim, Jung;Chun, Yong-Shik;Ryoo, Mun-Il
    • Korean journal of applied entomology
    • /
    • v.34 no.3
    • /
    • pp.278-286
    • /
    • 1995
  • Adaptation of Anisopteromalus calandrae maintained on rice weevil (Sitophilus oryzae) to an alternative host, adzuki bean weevil (Callosobruchus chinensis) was studied. A. calandrae required two generations to adapt to the adzuki been weevil. Through the adaptation, the mean($\pm$SEM) life span of th females became shorter $8.7\pm$1.3 days at the first generation to $6.9\pm$0.6 days at the second generation. Number of eggs laid per female increased from 29.3$\pm$7.7 to $68.2\pm$6.5. Consequently intrinsic rate of natural increase and net reproductive rate were increased. The generation time and population doubling time were decreased. The searching efficiency based on functional and numerical response of A. calandrae to the adzuki bean weevil were similar to each other, but the coefficient of variation decreased with the generation, suggesting that searching efficiency became stable when the parasitoid adapted to adzuki bean weevil. No time lag was required for A. calandrae adapted to the adzuki bean weevil to adapt again to th rice weevil and the searching efficiency of the parasitoid remained on a similar level for the first generation on.

  • PDF

Biological Characteristics of Amblyseius bomersleyi Schica (Acarina:Phytoseiidae) as a Predator of Tetranychus kanzawai kishida(Acarina: Tetranychidae) (긴털이리응애(Amblyseius womersleyi Schica)의 생태적 특성)

  • 김도의;이승찬;김상수
    • Korean journal of applied entomology
    • /
    • v.35 no.1
    • /
    • pp.38-44
    • /
    • 1996
  • These experiments were conducted to investigate the ecological characteristics of Amblyseius womersleyi Schica,which was biological agent in the integrated management of tea red spider mite, Tetranychus kanzawai Kishida.At four constant temperatures of 15, 20, 25, and 30$^{\circ}$C, the periods of A. womersleyi from egg to adult emergencewere 22.8, 9.6, 4.8, and 3.6 days, respectively. Developmental threshold and effectively cumulative degree-day from egg to adult emergence were 12.7"C and 61.4DD, respectively. Preoviposition periods of A.womersleyi were shorter than oviposition and postoviposition periods. The number of eggs laid per female was21.7, 28.1, 34.2, and 48.0 at the respective temperatures. The intrinsic rates of increase were estimated to be 0.064, 0.139, 0.349, and 0.402; the mean generation times were 36.0, 19.3, 8.6, and 7.7 days; the populationdoubling times were 10.8, 5.0, 2.0, and 1.7 days, respectively. A. womersleyi overwintered on green weeds, fallenleaves and in the soil surface as adult females. A. womersleyi gravid female consumed 3.0, 4.9, 15.7, and19.4 eggs of T. kanzawai per day at 15, 20, 25, and 30$^{\circ}$C, respectively. A. womersleyi protonymph consumed4.6 eggs, deutonymph 6.3 eggs, and female during oviposition consumed 19.4 eggs, and 6.8 eggs of T. kanzawaiduring postoviposition per day at 30$^{\circ}$C. at 30$^{\circ}$C.

  • PDF

A Study on the Predictive Power Improvement of Time Series Model with Empirical Mode Decomposition Method (경험적 모드분해법을 이용한 시계열 모형의 예측력 개선에 관한 연구)

  • Kim, Taereem;Shin, Hongjoon;Nam, Woosung;Heo, Jun-Haeng
    • Journal of Korea Water Resources Association
    • /
    • v.48 no.12
    • /
    • pp.981-993
    • /
    • 2015
  • The analysis of hydrologic time series data is crucial for the effective management of water resources. Therefore, it has been widely used for the long-term forecasting of hydrologic variables. In tradition, time series analysis has been used to predict a time series without considering exogenous variables. However, many studies using decomposition have been widely carried out with the assumption that one data series could be mixed with several frequent factors. In this study, the empirical mode decomposition method was performed for decomposing a hydrologic time series data into several components, and each component was applied to the time series models, autoregressive moving average (ARMA). After constructing the time series models, the forecasting values are added to compare the results with traditional time series model. Finally, the forecasted estimates from ARMA model with empirical mode decomposition method showed better performance than sole traditional ARMA model indicated from comparing the root mean square errors of the two methods.

A Case Study on Entrepreneurial Motivations of Independent Creative Firms (1인 창조기업의 창업동기에 관한 사례연구)

  • Shim, Jae-Hu;Choi, Myeong-Gil
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.10 no.11
    • /
    • pp.3363-3372
    • /
    • 2009
  • Continued jobless growth in economy, coupled with the current economic recession, is aggravating the situation of job market. In order to create more jobs and reduce the economic gap in a society, an independent creative firm of a sole entrepreneurs is suggested as an alternative mean. Understanding entrepreneurial motivations of a sole entrepreneur will be helpful in developing educational programs on starting an independent creative firm and in establishing a relevant government policy. This study, therefore, proposes a new model on entrepreneurial motivations in the independent creative firm and performs case study. The results of the study show that the personal environment and the personal characteristics of entrepreneurs have much effects on motivation of starting the independent creative firms. Among the personal environments, entrepreneurs' educational backgrounds, work experiences, and personal networks have great influences on entrepreneurial motivations. The processes of sustained entrepreneurship involve: (a) the determination of business ideas and goals, (b) the inception of a new business and managerial activities, (c) the entrepreneur's assessment of both intrinsic and extrinsic rewards of business performances, and (d) the adjustment of business ideas and goals in accordance with the results of the assessment. The results of the study could be applied in developing educational programs and consulting guidelines on independent creative firms and in establishing government's supportive policies on the firm.

Complexation of Cadmium(Ⅱ) with Soil Fulvic Acid : Effect of pH and Fulvic Acid Concentration (풀빅산과 카드뮴(Ⅱ)과의 착화합 반응 : 풀빅산의 농도와 pH의 영향)

  • Choe, Se Yeong;Jeong, Geun Ho;Jeon, Song Hui;Mun, Hui Jeong
    • Journal of the Korean Chemical Society
    • /
    • v.38 no.8
    • /
    • pp.585-589
    • /
    • 1994
  • The complexation of cadmium(II) with a well characterized local soil fulvic acid was investigated at different solution pH and fulvic acid concentration using ion selective electrode. The stability constants were determined using a continuous distribution model based on Scatchard Plot; this model takes into consideration the diversitv of cation binding sites on a naturally occurring organic macromolecules even if the nature of the binding sites may not be known. The mean value of $logKi(\mu)$ was found to increase at higher pH(pH 4.0: ${\mu}=3.79{\pm}0.74$ l\;mol^{-1}; pH 6.0: ${\mu}=4.51{\pm}0.78$ l\;mol^{-1}$), and in more dilute fulvic acid concentration([FA] = 50 mgl$^{-1}: {\mu}=4.16{\pm}0.60$ l\;mol^{-1}; [FA]=151 mgl$^{-1}:{\mu}=3.75{\pm}0.5\;l\;mol^{-1}$). The intrinsic constant(logKint) for binding at the strongest site was measured to be around $4.72\;l\;mol^{-1}$ at both pH4.0 and 5.0, but was found to be increased to $6.03\;l\;mol^{-1}$ when pH was 6.0.

  • PDF

The Substates with Mutants That Negatively Charged Aspartate in Position 172 Was Replaced with Positive Charge in Murine Inward Rectifier Potassium Channel (Murine Kir2.1)

  • So, I.;Ashmole, I.;Stanfield, P.R.
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.7 no.5
    • /
    • pp.267-273
    • /
    • 2003
  • We have investigated the effect on inducing substate(s) of positively charged residues replaced in position 172 of the second transmembrane domain in murine inward rectifier potassium channels, formed by stable or transient transfection of Kir2.1 gene in MEL or CHO cells. Single channel recordings were obtained from either cell-attached patches or inside-out patches excised into solution containing 10 mM EDTA to rule out the effect of $Mg^{2+}$ on the channel gating. The substate(s) could be recorded with all mutants D172H, D172K and D172R. The unitary current-voltage (I-V) relation was not linear with D172H at $pH_i$ 6.3, whereas the unitary I-V relation was linear at $pH_i$ 8.0. The relative occupancy at $S_{LC}$ was increased from 0.018 at $pH_i$ 8.0 to 0.45 at $pH_i$ 5.5. In H-N dimer, that was increased from 0.016 at $pH_i$ 8.0 to 0.23 at $pH_i$ 5.5. The larger the size of the side chain or $pK_a$ with mutants (D172H, D172K and D172R), the more frequent the transitions between the fully open state and substate within an opening. The conductance of the substate also depended upon the pKa or the size of the side chain. The relative occupancy at substate $S_{LC}$ with monomer D172K (0.50) was less than that in K-H dimer (0.83). However, the relative occupancy at substate with D172R (0.79) was similar to that with R-N dimer (0.82). In the contrary to ROMK1, positive charge as well as negative charge in position 172 can induce the substate rather than block the pore in murine Kir2.1. The single channel properties of the mutant, that is, unitary I-V relation, the voltage dependence of the mean open time and relative occupancy of the substates and the increased latency to the first opening, explain the intrinsic gating observed in whole cell recordings.

Bionomics of Caloglyphus sp.(Acarina : Acaridae) (가루응애류 Caloglyphus sp.의 생태에 관한 연구)

  • Park, Ji-Doo;Kim, Jong-Kuk
    • Journal of Forest and Environmental Science
    • /
    • v.13 no.1
    • /
    • pp.51-56
    • /
    • 1997
  • Developmental characteristics and reproductive ability of Caloglyphus sp. were examined under the constant temperature conditions. This mites has five stages ; egg, larva, protonymph, deutonymph and adult. All active instars preyed on larvae of pine gall midge, Thecodiplosis japonensis Uchida et Inouye. The developmental period from the egg to the adult decreased with temperature increase at a range between $15^{\circ}C$ and $30^{\circ}C$. The threshold of temperature and the thermal constant for the development from the egg to the adult were $8.2^{\circ}C$ and 122.0 day-degrees, respectively. At $25^{\circ}C$, survival rate from egg to deutonymph was estimated as 66.4%, and longevity of the adult was 12.3 days for male and 10.0 days for female. After a preoviposition period of 1 and 2 days female laid an average of 360.6 eggs each, almost all during the first half of their life time. The value of the net reproduction(Ro), the mean length of a generation(T) and the intrinsic rate of natural increase($r_m$) were calculated as 101.1, 9.3 days and 0.494 per female per day, respectively.

  • PDF

Bionomics of the Green Peach Aphid(Myzus persicae $S\H{u}lzer$) Adults on Chinese cabbage(Brassica campestris) (복숭아혹진딧물(Myzus persicae $S\H{u}lzer$) 성충의 수명과 생명표)

  • Kim, Ji-Soo;Kim, Tae-Heung;Lee, Sang-Guei
    • Korean journal of applied entomology
    • /
    • v.44 no.3 s.140
    • /
    • pp.213-217
    • /
    • 2005
  • Adult development and fecundity of the green peach aphid, Myzus persicae $S\H{u}lzer$, were studied at $15{\sim}32.5^{\circ}C$ with $60{\sim}70%$ RH under 16L:8D and the results were put together to build a life table. The longevity shortened as temperatures rose at and below $25^{\circ}C$ whereas it remained relatively constant at $27.5^{\circ}C$. Total fecundity was not significantly different at all temperatures except at $30^{\circ}C$. Daily fecundity gradually increased from $15\;to\;22.5^{\circ}C$. It was 5.1 at $25^{\circ}C$ and as temperatures either went down or up, it decreased to 2.8 at both $15^{\circ}C\;and\;30^{\circ}C$. Fecundity model built from total fecundity at various temperatures suggests that $18.3^{\circ}C$ was the optimum temperature for the maximum progeny of 51. Net reproduction rate RO was highest of 36.5 at $27.5^{\circ}C$. The intrinsic rate of increase per day $r_m$ and the finite rate of increase per day $\lambda$ were highest of 0.4 and 1.6, respectively and the doubling time Dt was shortest of 1.6. Constructed life table suggests that the optimum temperature for adult development for the green peach aphid was $27.5^{\circ}C$ at which the mean generation time was 8.1.