• Title/Summary/Keyword: availability growth

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Polymorphic stages of the fresh water blue-green alga, Gomphosphaeria aponina

  • Dwivedi, V.K.;Tandon, Richa;Tiwari, G.L.
    • ALGAE
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    • v.25 no.3
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    • pp.115-120
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    • 2010
  • The natural growth of a population of Gomphosphaeria aponina Kutzing (Chroococcales, Cyanoprocaryota) was studied in a cemented freshwater tank in Allahabad, India. This population appeared to be a polymorphic species. Different species of the genus Gomphosphaeria have been segregated based on morphological features of colonies, cells and mucilage. However, these features are not well defined for different species. Our observations revealed many feature variations and, interestingly, certain features that have been described for different Gomphosphaeria species were seen in a single population. In this study, records of such variable morphological features were possible due to the availability of numerous specimens and continuous observations for more than two years. Further, this study revealed two points: (i) more detailed morphological studies are required both from nature as well as in culture to identify critical differences among the species, and (ii) molecular characterization of taxa appears to be necessary for final species settlement.

Web services development methodology for the study (Mash-up을 활용한 웹 서비스 개발방법론에 대한 연구)

  • Jin, Hye-Jin;Lee, Hong-Cheol
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2007.11a
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    • pp.453-456
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    • 2007
  • Mashups are new type of interactive web applications, combining content from multiple services or sources at run time. The www is currently experiencing a revolutionary growth due to its increasing participative community software applications. One of the interesting aspects of the Web 2.0 evolution is the wide-availability of various Web applications as APIs or Web services. These APIs expose informational services on the Web and take many forms of remote invocation of functions using standard Web protocols and XML for data representations. The paper describes mashups from a number of angles, highlighting current developments while providing sufficient illustrations to indicate its potential implications.

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A study on the effect of discharge in a multiple spark ignition engine (다회수 스파크 점화기관의 방전효과에 관한 연구)

  • 이성열;한병호
    • Journal of the korean Society of Automotive Engineers
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    • v.11 no.5
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    • pp.55-64
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    • 1989
  • The effect of discharge have been investigated for condition of spark in a multiple spark ignition engine, as the spark duration, capacitive and inductive discharge energy were calculated for condition of spark by ignition wave and energy formula. The useful portion of spark discharge is divided into capacitance portion and inductance portion. It was found that capacitive discharge energy and spark duration were increased according to increasing number of spark, and inductive discharge energy was increased according to increasing spark interval. Therefore engine torque was increase and lean misfire limit was extended comparing with the standard ignition system. It found that spark energy was discharged within ignition delay period availability acted on the formation and growth of flame kernel, and total spark energy was increased according to increasing number of spark times, but discharged spark energy after ignition delay became unavailable energy. And the capacitive discharge energy has the dominant effect for stoichiomeric or not very rich air-fuel mixture but inductive discharge energy has the dominant effect for lean air-fuel mixture.

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Ecology and Biology of the Antarctic Soft - shelled Clam, Laternula elliptica ( Bivalvia : Laternulidae ) (남극큰띠조개 Laternula elliptica (이미패강 : 띠조개과 ) 의 생태 및 생물학적 특성)

  • 안인영
    • The Korean Journal of Malacology
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    • v.10 no.2
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    • pp.41-46
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    • 1994
  • The Antarctic soft-shelled clam, Laternula elliptica is widely distributed in shallow waters around the Antarctic Continent and islands. This bivalve species occurs in densepatches particularly in sheltered but frequently ice-impacted areas. This species mostly occurs at atound 20-30 m depth and is rarely found at depths shallower than 5 m where ice abrasion by drifting or grounded icebergs is severe. It burrows deep into sedimint(frequently >50 cm), which seems to be primarily a means for avoiding ice impacts. A pair of stout and highly extendable siphons appear to be a morphological reature to feed in the ice-scoured substrates while staying deep in the sedimint. As one of the largest bivalves in the Antarctic waters, L. elliptica appears to grow rapidly, reaching to a shell length of approximately 100 mm in 12 or 13 years. L. elliptica feeds sctively during summer when food is sufficiently provided, implying that food may be the most inportant fator regulating the growth. Seasonal variations in food availability, and metabolic process in starvation condition possibly during winter, however, are yet to be further investigated.

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Some Ecological and Physiological Features of the Antarctic Clam, Laternula elliptica (King and Broderip) in a Nearshore Habitat on King George Island

  • Ahn, In-Young;Chung, Ho-Sung;Choi, Kwang-Sik
    • Ocean and Polar Research
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    • v.23 no.4
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    • pp.419-424
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    • 2001
  • The Antarctic clam Laternula elliptica, is one of the most representative benthic invertebrates in the Antarctic nearshore waters. Endemic to the Antarctic, L. elliptica is widely distributed around the Antarctica occurring as dense patches in shallow sheltered areas and exhibits high biomass. Despite its apparent ecological importance, L. elliptica has rarely been studied until recently probably due to difficulties in sampling in the ice-impacted waters. Recent studies have revealed various aspects of its ecology and physiology. In this review, some physiological and ecological characteristics of this species are discussed in relation to some prevailing features of its habitat environment, in particular physical instability of habitat substrates and extreme seasonality of food availability.

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Nitrogen Utility during the Population Development with Different Clipping Treatments on Italian Rye Grass Field (Italian Rye Grass 초지군락의 청예처리빈도에 따른 생산성과 질소이용성)

  • 송승달
    • Journal of Plant Biology
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    • v.22 no.3
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    • pp.63-69
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    • 1979
  • The plant growth and net production, the nitrogen uptake and recycling, the nitrogen mobility and allocation to each organ, and the nitrogen utility from the Italian rye grass field during the population development were analyzed in comparison with different clipping treatments. The maximum dry matter standing crop and nitrogen quantity of harvest increased significantly, however, the annual amounts of dry matter and nitrogen assimilation showed little variations with increasing clipping frequencies. Plants treated with frequent clippings allocated relatively more nitrogen to leaves and less to roots during the experimental period. The amount of recycling of nitrogen decreased considerably due to frequent clippings. The annual averages of nitrogen utility indices changed in inverse relation to the nitrogen availability; such as 63, 58, 44 and 35 for C, A, M and J plots, respectively.

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Role of Sodium lon in Biodegradation of Nitroaromatic Compound by Activated Sludge and Pure Cultures

  • Jo, Kwan-Hyung
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.3
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    • pp.169-175
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    • 1999
  • 2,4-Dinitrophenol(DNP) is a metabolic uncoupler that prevents cells from creating energy for growth and it has been suggested that the availability of sodium ions may be important in mitigating the effects of uncouplers. Accordingly, the degradation of DNP was investigated using activated sludge which had been adapted to mineralize DNP. After the acclimation of the activated sludge, the effect of sodium ions on the toxicity of high concentrations(80 to 100mg/L) of DNP was investigated over a sodium ion concentration range of 9.3$\times$10-5 to 94mM. The concentration of sodium ions in the activated sludge mixed liquor seemed to have little effect on the DNP toxicity. However, a lack of sodium in the grwoth media resulted in a reduction of the DNP degradation rate by a bacterial isolate from the activated sludge culture identified as Nocardia asteroides.

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A Study on ENHPP Software Reliability Growth Model based on Exponentiated Exponential Coverage Function (지수화 지수 커버리지 함수를 고려한 ENHPP 소프트웨어 신뢰성장 모형에 관한 연구)

  • Kim, Hee-Cheul
    • The Journal of Information Technology
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    • v.10 no.2
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    • pp.47-64
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    • 2007
  • Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times, and estimation of the reliability and availability of a software product require quantification of a critical element of the software testing process : test coverage. This model called enhanced non-homogeneous poission process(ENHPP). In this paper, exponential coverage and S-coverage model was reviewed, proposes the exponentiated exponential coverage reliability model, which maked out efficiency substituted for gamma and Weibull model(2 parameter shape illustrated by Gupta and Kundu(2001). In this analysis of software failure data, algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE statistics for the sake of efficient model, was employed.

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Nutritional Requirements and Management Strategies for Farmed Deer - Review -

  • Shin, H.T.;Hudson, R.J.;Gai, X.H.;Suttie, J.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.4
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    • pp.561-573
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    • 2000
  • Knowledge concerning the nutritional requirements and nutritional problems of fanned deer is limited. Nutritional recommendations must be based on data from domestic ruminants and fanned deer. An understanding of the biology and adaptative characteristics of wild deer is essential for sensible application of sheep and cattle nutritional principles. Nutritional requirements of deer are generally separated into five categories: energy, protein, minerals, vitamins and water. Research on deer nutrition has primarily focused on energy, protein and minerals (phosphorus and calcium). Changes in the nutritional requirements that occur with gestation, lactation, breeding and antler growth should be coordinated with seasonal changes in nutrient availability from forage plants. This paper describes aspects of current knowledge of energy, protein, minerals, vitamins and water requirements. Nutritional problems of. fanned deer are described with recommendations for prevention or control. A comparison of production efficiency of deer, lamb, beef cattle and dairy cattle is included.

FEED RESOURCE AVAILABILITY AND UTILIZATION IN SMALLHOLDER PIG FARMS IN SRI LANKA

  • Ravindran, V.;Cyril, H.W.;Nadesalingam, P.;Gunawardene, D.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.4
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    • pp.311-316
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    • 1995
  • Data on available feed resources, feeding practices and nutrient adequacy of rations under small farm conditions in Sri Lanka were obtained in a baseline survey involving 104 pig farms. The results showed that a wide range of non-conventional feedstuffs are used for pig feeding under typical small farm conditions and that dietary protein quality is a major factor limiting productivity. Following the survey, two on-farm trials were conducted to evaluate cheaper, alternative feeding strategies. In trial 1, a test diet was formulated using several non-conventional feedstuffs and compared with a commercial feed that is normally fed in the farms. In trial 2, the possibility of improving growth rates by amino acid supplementation was evaluated. The results demonstrated that feed costs can be considerably lowered through these packages. Some problems inherent to on-farm livestock trials are highlighted.