• Title/Summary/Keyword: Growth form

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A generalized form of software reliability growth (소프트웨어 신뢰도 성장모델의 일반형)

  • 유재년
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.35C no.5
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    • pp.11-16
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    • 1998
  • We analyze the software reliability growth models for the specified period from the viewpoint of theory of differential equations. we defien a genralized form of reliability growth models as follws: dN(t)/dt = b(t)f(N(t)), Where N(t) is the number of remaining faults and b(t) is the failure rate per software fault at time t. We show that the well-known three software reliability growth models - Goel - Okumoto, s-shaped, and Musa-Okumoto model- are special cases of the generalized form. We, also, extend the generalized form into an extended form being dN(t)/dt = b(t, .gamma.)f(N(t)), The genneralized form can be obtained if the distribution of failures is given. The extended form can be used to describe a software reliabilit growth model having weibull density function as a fault exposure rate. As an application of the generalized form, we classify three mentioned models according to the forms of b(t) and f(N(t)). Also, we present a case study applying the generalized form.

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Two New Sponges of the Genus Halichondria(Halichondrida: Halichondriidae) from Korea

  • Kang, Dong-Won;Sim, Chung-Ja
    • Animal cells and systems
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    • v.12 no.1
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    • pp.65-68
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    • 2008
  • Two new marine sponges in the family Halichondriidae, Halichondria gageoenesis n. sp. and Halichondria muanensis n. sp. are collected from Gageodo Island and Yongjeong-ri, Hyeongyeong-myeon, Muan-gun, Korea during 2006-2007. H. gageoenesis n. sp. is similar to H. oshoro(Tanita, 1961) in type of spicule, but is different from the latter in growth form and size of spicule. The oxea of the new species is larger than H. oshoro's. The growth form of H. gageoenesis n. sp. is thick and consists of encrusting with numerous erect hollow cylindrical tubes, but H. oshoro is of massive form. H. muanensis n. sp is similar to H. retiderma(Dendy, 1921) in type of spicule and choanosomal skeleton, but it is different from the latter in growth form and size of spicule. The oxea is smaller than that of H. retiderma. The growth form is thick and consists of encrusting, with numerous erect hollow cylindrical tubes, compared with the massive lobose of H. retiderma.

Deer Antler Extract Selectively Suppresses Hyphal Growth in Dimorphic Fungus, Candida albicans

  • Park, Hyun-Sook;Jeon, Gil-Ja;Choi, Won-Ja
    • Journal of Microbiology and Biotechnology
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    • v.8 no.3
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    • pp.291-294
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    • 1998
  • Transfer of Candida albicans grown in Sabouraud medium to the RPMI medium induces the transition from a nonpathogenic yeast form to a pathogenic hyphal form. This transition was severely inhibited in a dose-dependent manner when deer antler extract was added to the RPMI medium in a nontoxic range (up to $500{\mu}g$). In that range, deer antler extract inhibited the hyphal transition and cell growth, whereas no effect was observed on the yeast growth. When hydrophobic or hydrophilic fractions were prepared by detergent-solubilization of deer antler extract, the hydrophobic fraction showed a large degree of inhibition of the hyphal growth in Candida albicans. Neither fraction affected the growth in the yeast form. The pattern of chitin localization in the culture of the yeast form grown in RPMI in the presence of deer antler extract was confirmed by calcofluor staining and this exhibited strongly the suppression of hyphal transition.

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Comparison of Growth Performance and Whole-body Amino Acid Composition in Red Seabream (Pagrus major) Fed Free or Dipeptide Form of Phenylalanine

  • Kim, Sung-Sam;Rahimnejad, Samad;Song, Jin-Woo;Lee, Kyeong-Jun
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.8
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    • pp.1138-1144
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    • 2012
  • This study was conducted to evaluate the efficacy of the dipeptide form of phenylalanine as a new source of amino acid in terms of growth performance and whole-body amino acid composition in comparison to the free form for red seabream (Pagrus major). Fish ($1.46{\pm}0.001g$) were fed four isonitrogenous and isocaloric experimental diets containing 0.7 or 1.4% phenylalanine either in free or dipeptide form. A feeding trial was carried out in three replicates and the fish were fed to apparent satiation for six weeks. At the end of the feeding trial, feed intake of fish was influenced by both phenylalanine form and level and significantly higher values were obtained at an inclusion level of 0.7% and by the use of dipeptide form. However, the other growth parameters did not significantly differ among treatments. Whole-body amino acid compositions revealed no significant changes in concentrations of both essential and non-essential amino acids regardless of the increase in phenylalanine levels or the use of its different forms. The finding in this study indicates that juvenile red seabream can utilize dipeptide phenylalanine as efficiently as free form without any undesirable effects on growth performance or whole-body amino acid composition.

Four New Records of Two Genera Balanophyllia and Cladopsammia (Anthozoa: Hexacorallia: Scleractinia: Dendrophylliidae) from Korea

  • Choi, Eunae;Song, Jun-Im
    • Animal Systematics, Evolution and Diversity
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    • v.30 no.3
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    • pp.183-190
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    • 2014
  • The four species of the family Dendrophylliidae are newly recorded in Korea: Balanophyllia (Balanophyllia) cumingii Milne Edwards and Haime, 1848, Balanophyllia (Balanophyllia) vanderhorsti Cairns, 2001, Cladopsammia eguchii (Wells, 1982), and Cladopsammia gracilis (Milne Edwards and Haime, 1848). The two genera of Balanophyllia and Cladopsammia, to which the four species belong, are newly recorded in Korea. They were collected from the subtidal zones in Jeju-do Island, Korea by SCUBA diving from 1987 to 2012. This study aims to identify the four dendrophyllid species based on external and internal morphological characters including growth form, size, budding, and color of colonies, shape and size of corallites, columella, theca, and septa. Balanophyllia (Balanophyllia) cumingii is distinguished by its solitary growth form, small and low subturbinate corallite with enlarged calice, and expanded basal part, exsert first and second septa, and Pourtal$\acute{e}$s plan. Balanophyllia (Balanophyllia) vanderhorsti is characterized by its quasi-colonial growth form, subturbinate corallites with compressed calice, thick theca, and Pourtal$\acute{e}$s plan. Cladopsammia eguchii is characterized by its phaceloid growth form of compressed corallites basally united with common coenosteum, flat spongy columella, thick theca, and Pourtal$\acute{e}$s plan. Cladopsammia gracilis is distinguished by its phaceloid growth form of corallites basally united with common coenosteum, and pronounced Pourtal$\acute{e}$s plan forming flower patterns.

A STUDY OiM THE MORPHOLOGY OF CHIN IN RELATION TO VERTICAL DYSPLASIA OF CRANIOFACIAL COMPLEX (안모수직 부조화에 따른 하악이부 형태에 관한 연구)

  • Cha, Bong-Keun;Suhr, Cheong-Hoon
    • The korean journal of orthodontics
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    • v.20 no.1
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    • pp.135-156
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    • 1990
  • This study was undertaken to investigate the difference of chin morphology and mandibular form in relation to different mandibular growth direction. The subject was divided into three group i.e., control group, vertical group, and horizontal group, according to the criteria of $Bj{\ddot{o}}rk$ sum, and each group was composed of 15 females and 15 males. Medial axis analysis in addition to the routine cephalometric analysis using P.I.A.S. (personal image analysing system) was carried out to find out the differences of mandibular morphology on each group. The results were as follows: 1. The area of symphysis was larger in horizontal growth group than that of vertical growth group. 2. Protruding chin area was also larger in horizontal growth group than that of vertical growth group. 3. There was a close correlationship between protruding chin area and other form of mandible. 4. Antegonial notch depth and ramus posterior contour depth was deeper in vertical growth group than in horizontal growth group, and antegonial notch depth was more influenced by anterior part of notch than posterior part of notch. 5. Mental medial axis and incisal medial axis length, in relation to corpus medial axis length was larger in vertical growth group than in horizontal growth group.

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Life history and growth pattern on the erigeron annuus (개망초 ( Erigeron annuus L. ) 의 生活史 및 生育特性)

  • Lee, Ho-Joon;Tae-Sung Kim
    • The Korean Journal of Ecology
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    • v.14 no.2
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    • pp.211-230
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    • 1991
  • The germinatin of e. annuus continued from the middle ofmay to mid-october. The maximum germination occurred on the mid-july. The period bloom of was distingushed amongs the different growth forms ; a orm pr of biennial and a form of pr perennial flowering from the mid-may to mid-september, and a form ps biennial blossom from the beginning of October to earlynovember. the dispersal of seed for(a form pr)occurred from early June to the mid-september. A rotte, germinating from summer to autumn, could classified into several growth forms; individuals without a critical leaf area for bolting until september and October, become a form ps of biennial, whicth did not proceed toreproductive growth unitl the next year, even thought wintering. individuals flowered on 3 years after germination become a form pr of perennial. The growth formular of aform pr of bennial, grown in a pot was w=20.2[1+$3.36{\times}10^3$(-0.062t)]$^{-1}$. The maximum relative growth rate(rgr) was 0.062g/g/day and the maximum net assimlation rate(nar) 0.089g/g/day. Therelative growth among each organ was shown as R=0.12 $T^{1.15}$between the avove-ground part(t) and the below- ground part(r). the relation between the avove-ground part(t) and the ratio of stem weight(wi) was ws/wi=2.56 $T^{0.35}$. n.p.k. was largely distributed on a leaf throughoutthe total growth period. while growing, it tended to decrease on the vegetative organ gut vice versa on the reproductive organ. however, nitrogen was more widely distributed on a leaf then in the reproductive organ.

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Stem and Stand Taper Model Using Spline Function and Linear Equation (Spline 함수(函數)와 선형방정식(線型方程式)을 이용한 수간(樹幹) 및 임분간곡선(林分幹曲線)모델)

  • Lee, Woo Kyun
    • Journal of Korean Society of Forest Science
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    • v.83 no.1
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    • pp.63-74
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    • 1994
  • One of the essential factors to estimate the stem and stand growth is to correctly portray a stem form (profile). It is also required to numerically approximate a stem form in order to dynamically grasp and represent a stand growth. A whole stem form seems to be a conical form but a stem outline at various positions tapers off differently. Accordingly it is difficult to model a whole stand form with single taper equation. A stem taper equation with different coefficients on each subinterval can be useful tools to accurately portray a stem form. This article presents the derivation method of individual stem taper curve using spline function. It is also in this paper aimed to study how a stand taper curve car, be derived from the population of single stem taper curve in a stand. These taper equations numerically formulated enable to dynamically represent and prognosticate the development process of a stand and prepare the foundation of variety on growth model study and rational forest planning model.

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A Study on Corrosion Fatigue Crack Growth Behavior in Al 7075-T651(II) (Al 7075-T651의 부식피로균열 성장 거동에 관한 연구(II))

  • 한지원;우흥식
    • Journal of the Korean Society of Safety
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    • v.14 no.2
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    • pp.3-10
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    • 1999
  • Fatigue crack growth rates in commercial plate of high strength Al 7075-T651 were investigated for the T-L direction in air, water and sea water. In this paper the effect of cyclic load wave-form(trapezoid and triangle) on fatigue crack growth rates in air, water and sea water environments were investigated using standard LEFM testing procedures. It was founded that the fatigue crack growth behaviors were not affected by cyclic load wave-forms. In region II (stable crack growth region), the fatigue crack growth behaviors were insensitive to cyclic load wave-forms and were sensitive to environment i.e. fatigue crack growth behaviors were higher in sea water than in air for all cyclic load wave-form. The result of fractographical morphology in air, water and sea water by SEM showed obvious dimple rupture and typical striation in air, but transgranular fracture surface in water and sea water. The values m are not affected by corrosion environments but C are different values.

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Voluntary Intake and Digestibility of Fresh, Wilted and Dry Leucaena (Leucaena leucocephala) at Four Levels to a Basal Diet of Guinea Grass (Panicum maximum)

  • Aregheore, Eroarome Martin
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.8
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    • pp.1139-1146
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    • 2002
  • Sixty crossbred Anglo-Nubian goats (growing females), 18-24 mo of age, with a mean pre-experimental live weight of $20.9{\pm}0.44kg$ were used to investigate voluntary dry matter intake (DMI) and digestibility of supplements of Leucaena leucocephala (LL) leaves to a basal diet of guinea grass. The experiment was a 3 forms of presentation: fresh, wilted and $dry{\times}4$ levels of supplementation: 10, 20, 30 and 40% of total forage allowance with LL leaves. The goats were assigned based on weight and age to one of the twelve diets in a randomized manner and each level had five animals (replicates) per diet for 56 days. The form of presentation of LL leaves had effects on dry matter (DM) and nutrient composition. DM and NDF were higher in the dry LL leaves (p<0.05). In the diets, CP increased as the level of supplementation with LL leaves increased (p<0.05). Mean CP was similar in the fresh ($14.8{\pm}3.5%$), wilted ($14.3{\pm}3.3%$) and dry forms ($13.9{\pm}3.1%$). Neutral detergent fibre (NDF) decreased linearly (p<0.05) with increase in levels of supplementation. Organic matter (OM) followed the trend of CP concentration (p<0.05). Drying was observed to reduce the availability of CP at the different levels of supplementation and subsequently this affected the NDF of the diets. DM intake of the goats on the fresh and wilted LL leaves was significantly higher (p<0.05) than in those on the dry LL leaves. DM intake of the basal diet was observed to decrease as the level of supplementation (p<0.05) increased regardless of the form of presentation of LL. Growth rate was best (p<0.05) on the fresh form followed by wilted and the least in the dry form. Growth rate decreased linearly (p<0.05) with increase in the level of supplementation in the dry form. The form of presentation and level of supplementation influenced DM, CP and OM digestibility (p<0.05). Except for NDF, the digestibility of DM, CP and OM were better (p<0.05) in the goats on fresh LL leaves compared to the wilted and dry leaves. Based on the data on DMI, growth rate and apparent nutrient digestibility coefficients, the results suggest that LL leaves is best utilized when fed fresh or wilted to goats. In the dry form of presentation, the best level of supplementation without a reduction in voluntary DMI and growth rate is the 20%. In the fresh and wilted form, LL leaves could be fed up to the 40% level with improved DMI, growth rate and nutrient utilization.