• 제목/요약/키워드: Regular relative growth

검색결과 13건 처리시간 0.021초

SUM AND PRODUCT THEOREMS OF RELATIVE TYPE AND RELATIVE WEAK TYPE OF ENTIRE FUNCTIONS

  • Choi, Junesang;Datta, Sanjib Kumar;Biswas, Tanmay;Sen, Pulakesh
    • 호남수학학술지
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    • 제37권1호
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    • pp.65-97
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    • 2015
  • Orders and types of entire functions have been actively investigated by many authors. In this paper, we aim at investigating some basic properties in connection with sum and product of relative type and relative weak type of entire functions.

Optimum Model for Analyzing Lifetime Profitability of Holstein Cows

  • Shadparvar, A.A.;Nikbin, S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제21권6호
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    • pp.769-775
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    • 2008
  • This study was on the relative net income (RNI) for 18,286 Iranian Holstein cows from 799 herds, with first freshening between 1991 and 2000. Two kinds of production system, which differed mainly in milk pricing system and feed cost, were considered. Four different models adopted from the literature were examined to find the optimum model. They differed by the cost of rearing and growth after first calving and they needed different amounts of economic data at the farm level. Results showed that four measures of RNI were highly correlated (>0.96) and could be used equally to measure lifetime profitability of cows. Therefore, in herds without a regular system for recording economic and management data, use of the simplest model is recommended. Multiple regression analysis revealed that RNI was affected by age at first freshening, milk yield and days of productive life (DPL), regardless of production system, and a similar breeding goal could be defined for the two systems. Multiple regression analysis of RNI showed that in order to obtain an unbiased estimate of economic value for DPL, the per day milk yield, not total lifetime milk yield, should be included in the regression model along with DPL. Regression analysis suggested that it is possible to predict RNI using information on age at first freshening along with the length of first lactation and per day milk yield with a coefficient of determination ranging from 0.44 to 0.47.

PFC법에 있어서의 Al-Cu 다결정리본의 응고특성 (Solidification Characteristics of Al-Cu Polycrystalline Ribbons in Planar Flow Casting)

  • 이경구;이상목;홍준표
    • 한국주조공학회지
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    • 제15권4호
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    • pp.408-415
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    • 1995
  • Polycrystalline Al-Cu ribbons were produced by planar flow casting(PFC). Solidification behavior and microstructual changes of the ribbons have been investigated as a function of ribbon thickness and processing parameters. The solidification front velocity, V varies within the ribbon, decreasing with increasing the distance, S from the wheel-contact surface, as $V=17.6S^{-1}$. In Al-4.5wt%Cu alloy, rapid decrease in solidification velocity toward the free surface causes a change in solidification morphology from planar to cellular, and finally, to dendritic. The length and inclination of columnar grains solidified with planar front were related to the wheel velocity. The transition from particulate degenerate eutectic structure to regular lamellar eutectic structure was observed to be caused by a difference of the relative growth velocites of ${\alpha}-Al$ and ${\theta}$ during solidification in the Al-Cu eutectic alloy.

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장수명공동주택의 유지관리업무프로세스 구축에 관한 연구 - 관리자를 위한 유지관리업무프로세스를 중심으로 - (Study on the Development of Maintenance Process in Long-Life Housing - Focus on the Development of Maintenance Process for the Manager -)

  • 지장훈;김수암;윤상조
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2009년 춘계학술발표대회 논문집
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    • pp.344-349
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    • 2009
  • To be Low Carbon and Green Growth, it is necessary that Long-Life Housing based on Green Technology is supplied. The main concern at the moment is developing Sustainable Housing relative to Life-Cycle or Life-Style of the residents, and the resident of Remodeling or Redevelopment. This study is aim to be Development of Maintenance Process in order to make steady dwelling when supplying Long-Life Housing that separates Support(Skeleton) and Infill different from the existing Short-Life Housing, and has durability, alterability, available remodeling, easy maintenance. Long-Life Housing should consider the maintenance about movement and variableness. In contrast, the maintenance of the existing Housing is regular maintenance, change and repair by damage. As well as Long-Life Housing should be demanded proper Development of Maintenance Process because of difference of Housing in concept, design and Construction. Therefore, this study looks into problems when applying Development of Maintenance Process in Long-Life Housing, and shows Development of Maintenance Process about the efficient Long-Life Housing for the manager.

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Geometric and mechanical properties evaluation of scaffolds for bone tissue applications designing by a reaction-diffusion models and manufactured with a material jetting system

  • Velasco, Marco A.;Lancheros, Yadira;Garzon-Alvarado, Diego A.
    • Journal of Computational Design and Engineering
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    • 제3권4호
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    • pp.385-397
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    • 2016
  • Scaffolds are essential in bone tissue engineering, as they provide support to cells and growth factors necessary to regenerate tissue. In addition, they meet the mechanical function of the bone while it regenerates. Currently, the multiple methods for designing and manufacturing scaffolds are based on regular structures from a unit cell that repeats in a given domain. However, these methods do not resemble the actual structure of the trabecular bone which may work against osseous tissue regeneration. To explore the design of porous structures with similar mechanical properties to native bone, a geometric generation scheme from a reaction-diffusion model and its manufacturing via a material jetting system is proposed. This article presents the methodology used, the geometric characteristics and the modulus of elasticity of the scaffolds designed and manufactured. The method proposed shows its potential to generate structures that allow to control the basic scaffold properties for bone tissue engineering such as the width of the channels and porosity. The mechanical properties of our scaffolds are similar to trabecular tissue present in vertebrae and tibia bones. Tests on the manufactured scaffolds show that it is necessary to consider the orientation of the object relative to the printing system because the channel geometry, mechanical properties and roughness are heavily influenced by the position of the surface analyzed with respect to the printing axis. A possible line for future work may be the establishment of a set of guidelines to consider the effects of manufacturing processes in designing stages.

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.

출토금속 문화재의 보존과 현황 (The Conservation and Current Condition of the Excavated Metallic Objects)

  • 문환석
    • 보존과학회지
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    • 제6권2호
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    • pp.141-148
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    • 1997
  • 각종 국토개발사업이 본격적으로 시작된 1970년대 이후 그에 따른 발굴조사도 매년 증가되고 있다. 다양한 재질로 이루어진 유물은 출토후 보관환경에 따라 돌이킬 수 없는 손상을 받을 수 있다. 출토 유물의 보존에 대한 중요성은 증가되고 있으나, 발굴을 담당하는 기관과 비교하여, 출토된 유물을 보존처리하는 기관은 소수에 불과한 실정이다. 일반적으로 출토된 금속유물은 불안정하여 쉽게 손상되어진다. 특히 주조철제는 발굴후 건조되지 않도록 해야 한다. 이는 출토된 주조철제가 흙, 부식층과 금속심으로 이루어진 층 사이에서 건조로 인해 유물이 순간적으로 붕괴되어지기 때문이다. 출토된 금속유물의 안전한 보존방법은 다음과 같이 요약할 수 있다. (1)먼저 발굴현장에서 금속유물은 환경변화에 따른 손상을 방지하기 위해 유물포장용 특수비닐로 밀봉처리 하거나 알칼리 용액속에 침적시키는 것이다. (2)현장에서 임시 보존처리후 유물은 보존처리실에서 안전한 방법에 의한 처리를 해야 한다. (3)처리된 유물은 일정한 온${\cdot}$습도 유지, 주기적인 상태조사, 자외선 차단 등 안정한 보관환경을 유지시켜야만 재부식을 방지할 수 있다.

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Populus alba × P. grandidentata 조직배양묘(組織培養苗)의 토양(土壤)에서의 활착(活着)과 생장(生長) (Survival and Early Growth of Populus alba × P. grandidentata In Vitro Culture Plantlets in Soil)

  • 전영우
    • 한국산림과학회지
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    • 제66권1호
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    • pp.1-7
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    • 1984
  • 무균상태(無菌狀態)와 최적(最適)의 환경조건(環境條件)에서 배양(培養)된 Populus alba ${\times}$ P. grandidentata 조직배양묘(組織培養苗)를 일반(一般) 온실(溫室)의 환경조건(環境條件)에 경화(硬化)시키고, 높은 활착율(活着率)과 빠른 조기생장(早期生長)을 위해서 3가지 배양토(培養土)에 이식(移植)하여 3주간(週間) misting bench에서 경화(硬化)시킨 후(後) 생육상태(生育狀態)를 비교(比較) 관찰하였다. Terralite, Jiffy mix, Jiffy-7-pellet의 3가지 배양토중(培養土中) Terralite가 조직배양묘(組織培養苗)의 활착(活着)과 조기생장(早期生長)에 가장 좋았으며, 온실이식(溫室移植) 3주후(週後)의 활착율(活着率)은 각각 평균(平均) 90%, 86.7%, 86.7%였다. 액아(腋芽)에서 기원(起源)한 조직배양묘(組織培養苗)와 multiple shoot에서 기원(起源)한 조직배양묘(組織培養苗)에 대(對)한 외부형태(外部形態)의 비교(比較)에는 차이(差異)가 없었으나 생장(生長)에 대(對)한 비교(比較)에는 유의성(有意性)이 인정되었다. 온실내(溫室內)에서 경화기간(硬化期間)동안 작고 좁으며 가는 잎과 줄기, 짧은 internode와 같은 유성(幼性)이 조직배양묘(組織培養苗)에 나타났으나, 이식(移植) 5~6주후(週後)에는 정당적(正當的)인 식물체(植物體)의 형태(形態)로 생장(生長)이 진작되었다.

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폐쇄형 묘생산 시스템에서 감자 플러그묘의 생장에 미치는 광합성유효광양자속의 영향 (Growth of Potato Plug Seedlings as Affected by Photosynthetic Photon Flux in a Closed Transplants Production System)

  • 김용현;김현준;이지원;김정만
    • Journal of Biosystems Engineering
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    • 제33권2호
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    • pp.106-114
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    • 2008
  • This study was performed to analyze the distribution of air current speed, $CO_2$ concentration, and photosynthetic photon flux (PPF) in a closed transplants production system (CTPS) for producing quality transplants. And the effect of PPF on the growth of potato (Solanum tuberosum L. cv. Dejima) plug seedlings was analyzed. Uniformity of the air current speed in CTPS was improved by installing perforated floors in duct for air circulating and by adjusting of air flow rate of the fan connected to air conditioning unit used in this study, Measured $CO_2$ concentrations were measured $409{\pm}13$, $950{\pm}25$, and $1,550{\pm}35\;{\mu}mol{\cdot}mol^{-1}$ for setting values of 400, 950, and $1,550\;{\mu}mol{\cdot}mol^{-1}$, respectively. Uniformity of PPF by adding each one the single fluorescent lamp of 20 W at both ends of the single fluorescent lamps of 40 W was highly improved. While the average PPF measured under the twin fluorescent lamps of 55 W installed at regular intervals of 10 cm was decreased by increasing the vertical distance from the lighting sources, the ratio of average PPF measured at both ends to PPF measured in the center was 74-79%. Five levels ($100{\pm}9$, $150{\pm}14$, $200{\pm}17$, $250{\pm}24$ and $300{\pm}31{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) of PPF were provided to investigate the effect of PPF on plant height, fresh weight and dry weight of potato plug seedlings produced in CTPS. Plant height was decreased by increasing PPF. Maximum fresh weight and dry weight were shown under PPF of $250{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Thus PPF of $250\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ was enough to produce quality potato transplants under air temperature, photoperiod, and relative humidity of $20^{\circ}C$, 16/8 h, and 70%, respectively. It was concluded that quality indices such as plant height, fresh weight and dry weight could be improved by illuminating of adequate PPF from artificial lighting sources.