• Title/Summary/Keyword: High productivity

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Determinants of Inventor Productivity: An Empirical Result from Panel Regressions Using Network Characteristics (발명자 생산성 결정요인: 네트워크 특성을 이용한 패널회귀분석결과)

  • Choo, Kineung
    • Journal of Technology Innovation
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    • v.25 no.3
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    • pp.83-113
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    • 2017
  • This paper constructs panel data of inventors listed on patents applied for the KIPO during 1991-2005 and analyzes the effects of network characteristics on inventor productivity. The findings are as follows: ⅰ) Strong ties within a network have positive effects on inventor productivity. ⅱ) An inventor with high centrality shows high producitivity. ⅲ) Technological diversity of a network enhances inventor productivity. ⅳ) An inventor belonging to a network of good quality shows higher productivity. ⅴ) Network size is positively related with inventor producitvity. ⅵ) A lone inventor shows the highest productivity among types of inventors, and a co-inventor with the experience of standalone invention is more productive compared to an inventor with only the experience of co-invention. ⅶ) The productivity effects of network variables differ across regions. ⅷ) Differences among regions do not decrease though geographical boundaries become less important.

Effect of the pat, fk, stpk Gene Knock-out and mdh Gene Knock-in on Mannitol Production in Leuconostoc mesenteroides

  • Peng, Yu-Wei;Jin, Hong-Xing
    • Journal of Microbiology and Biotechnology
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    • v.28 no.12
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    • pp.2009-2018
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    • 2018
  • Leuconostoc mesenteroides can be used to produce mannitol by fermentation, but the mannitol productivity is not high. Therefore, in this study we modified the chromosome of Leuconostoc mesenteroides by genetic methods to obtain high-yield strains for mannitol production. In this study, gene knock-out strains and gene knock-in strains were constructed by a two-step homologous recombination method. The mannitol productivity of the pat gene (which encodes phosphate acetyltransferase) deletion strain (${\Delta}pat::amy$), the fk gene (which encodes fructokinase) deletion strain (${\Delta}fk::amy$) and the stpk gene (which encodes serine-threonine protein kinase) deletion strain (${\Delta}stpk::amy$) were all increased compared to the wild type, and the productivity of mannitol for each strain was 84.8%, 83.5% and 84.1%, respectively. The mannitol productivity of the mdh gene (which encodes mannitol dehydrogenase) knock-in strains (${\Delta}pat::mdh$, ${\Delta}fk::mdh$ and ${\Delta}stpk::mdh$) was increased to a higher level than that of the single-gene deletion strains, and the productivity of mannitol for each was 96.5%, 88% and 93.2%, respectively. The multi-mutant strain ${\Delta}dts{\Delta}ldh{\Delta}pat::mdh{\Delta}stpk::mdh{\Delta}fk::mdh$ had mannitol productivity of 97.3%. This work shows that multi-gene knock-out and gene knock-in strains have the greatest impact on mannitol production, with mannitol productivity of 97.3% and an increase of 24.7% over wild type. This study used the methods of gene knock-out and gene knock-in to genetically modify the chromosome of Leuconostoc mesenteroides. It is of great significance that we increased the ability of Leuconostoc mesenteroides to produce mannitol and revealed its broad development prospects.

An Investigation into Research Productivity in the Journal of Consumer Behavior

  • Shin, Dong-Jin;Huh, Mooyul
    • Journal of Distribution Science
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    • v.13 no.2
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    • pp.45-53
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    • 2015
  • Purpose - This study strives to discern trends in research productivity in the Journal of Consumer Behavior. It will identify prolific authors and institutions in articles over ten years (2004-2013). Research design, data, and methodology - The Journal of Consumer Behavior was chosen and articles over ten years were analyzed. Research productivity was determined by categorizing the data into four themes: number of authors per article, author affiliated institutions, a list of prolific authors over a ten-year period, and author-affiliated countries. Results - Authors have a propensity to collaborate on a research paper, yielding a high frequency of articles with two or three authors in a single publication. In addition, author and institution productivity was highest in North America and Europe. Conclusions - The research productivity of the Journal of Consumer Behavior is unprecedented. The trends and insights from this study will allow academics in the area of consumer behavior to observe leading authors and institutions. Moreover, speculations about the leading countries and institutions, not to mention top prolific authors in consumer behavior, will be elucidated in this study.

Development of a sustainable land-based Gracilaria cultivation system

  • Kim, Jang K.;Yarish, Charles
    • ALGAE
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    • v.29 no.3
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    • pp.217-225
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    • 2014
  • Land-based seaweed (Gracilaria) cultivation systems may provide products with high quality and biosafety for human consumption, as well as for other high value applications. However, a limitation for this land based system is high management costs. The objective of this study was to determine if the management costs for Gracilaria cultivation can be reduced without a decrease in productivity by using $CO_2$ injection along with a high stocking density and high photosynthetically active radiation (PAR), and commercially available fertilizers. When Gracilaria tikvahiae was cultivated at a high stocking density and high PAR, coupled with $CO_2$ enhancement, the productivity was significantly higher than that at a lower stocking density, low light without $CO_2$ injection. We also found that G. tikvahiae grown in a medium of commercially available fertilizer (Jack's Special, JS) showed a similar growth rate and productivity to that grown in von Stosch's enriched (VSE) seawater, while the cost for JS media is only 2% of the cost for VSE. These results suggest that $CO_2$ injection and commercial fertilizer may be a potential way to provide sustainability in land-based Gracilaria cultivation systems.

A Study on in Ball End Mill Cutting Operation the Cutting characteristics (Ball End Mill 가공시 가동특성에 관한 연구)

  • 오영생
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1997.10a
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    • pp.196-201
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    • 1997
  • The biggest challenge facing today's manufacturing industry is better quality and high productivit. From an economic point of view, productivity is the most important parameter, as high productivity will reduce the cost. However, the customers of today are not only cost concerned, but also quality conscious. So high accuracy levels should also be achieved in the manufacturing process. The aim of this paper is to get a comprehensive understanding of its machinability properties and to investigate the relationship between cutting conditions and surface roughness for Ball End Mill cutting process so as to enhance its practical application.

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A Comparison of Methods for Estimating the Productivity of Zostera marina

  • Park, Sang-Rul;Li, Wen-Tao;Kim, Seung-Hyeon;Kim, Jae-Woo;Lee, Kun-Seop
    • Journal of Ecology and Environment
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    • v.33 no.1
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    • pp.59-65
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    • 2010
  • Because seagrass production significantly contributes to the biodiversity and production of coastal and estuarine ecosystems, accurate estimation of seagrass productivity is a critical step toward understanding the ecological roles of seagrass in these ecosystems. To develop an accurate and effective method of measuring seagrass productivity, we estimated leaf productivity of eelgrass (Zostera marina) on the southern coast of Korea using three methods, the conventional leaf marking method, the elongation-mass method (Short '87 method), and the plastochrone method. In each season, shoots were pierced through the bundle sheath using a hypodermic needle and were collected after 2-4 weeks had elapsed to estimate their productivity. The leaf elongation and the leaf plastochrone intervals varied significantly among seasons. On an annual basis, the conventional leaf marking method showed the lowest leaf productivity estimates compared to the elongation-mass method and the plastochrone method, suggesting that the conventional leaf marking method underestimated leaf productivity as it ignored leaf maturation processes and new leaf growth within the sheath. Since the elongation-mass method considered leaf maturation processes, this method produced higher leaf productivity estimates than the conventional leaf marking method. On an annual basis, the plastochrone method produced the highest leaf productivity estimates. Below-ground productivity, which can be easily estimated using the plastochrone method, ranged between 3.29 and 5.73 (mg dry weight $shoot^{-1}\;day^{-1}$) and accounted for about 17.8% to 30.3% of total productivity. Because of the high contributions of below-ground productivity to total seagrass production, we suggest that the plastochrone method is an effective and simple technique for assessing both above- and below-ground productivities.

Studies on the Classification, Productivity, and Distribution of $C_3, C_4$ and CAM Plants in Vegetations of Korea(II. Production and Productivity of $C_3; and; C_4$Type Plants) (한국의 식생에 있어서 $C_3, C_4$ 및 CAM 식물의 분류, 생산력 및 분포에 관한 연구 2. $C_3;와;C_4$형 식물의 물질생산과 생산력)

  • Lee, Sung-Kyu;Chang, Nam-Kee
    • The Korean Journal of Ecology
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    • v.6 no.2
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    • pp.114-127
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    • 1983
  • The production and productivity of $C_3 and C_4$ type plants in Korea was studcied In the areas, in which the summer temperature is above $30^{\circ}C,;C_3$ type plants showed“M” type productivity curves exhibiting two peaks in spring and autumn, and C4 type plants showd “Bell” type productivity curves which show one peak in summer(Figs. 1,2,3,4,5). From the result of researching the standing crop of $C_3 and C_4$type plants dcuring August and September in which the standing crop reaches the highest peak, the dominant plants in the natural grass vegetation were almost all of $C_4$ type plants, showing the high standing crop, while the standing crop of $C_3$ type plants shows its high peak in the humid areas, riversides and dams.

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A Study on the Model of the Container Transport Vehicle with High Productivity (고생산성 컨테이너 이송차량 모델 연구)

  • Kim, Woo-Sun;Choi, Young-Seok
    • Journal of Navigation and Port Research
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    • v.30 no.8 s.114
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    • pp.691-697
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    • 2006
  • The objective of this study is to develop the alternative model of the container transport vehicle of high productivity for the purpose of the increase of terminal productivity. In order to develop the alternatives, we analyze the technical specification of existing transport vehicles such as YT(Yard Tractor), S/C(Straddle Carrier), SHC(Shuttle Carrier), and AGV(Automated Guided Vehicle) and investigate the operation and performance of transport vehicles to classify the technical generation. The development alternative of transport vehicle presented in this study will usefully be apply to advanced container terminal with higher productivity in near future.

A Study on the Effects of Heat Stress on Feedlot Environment and Productivity of Dairy Cattle (고온 환경이 젖소의 생산성 및 축사환경에 미치는 영향 연구)

  • Kim, Byul;Lim, Joung-Soo;Cho, Sung-Back;Hwang, Ok-Hwa;Yang, Seung-Hak
    • Journal of Animal Environmental Science
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    • v.20 no.2
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    • pp.63-68
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    • 2014
  • Environmental heat stress by global warming has a severe effect on the productivity of livestock and, in particular, on that of dairy cattle. Heat stress during high temperature environment directly and indirectly affects milk yield, milk quality and physiological response. This study was conducted to investigate the effects of heat stress on productivity and physiological responses of livestock. Temperature-humidity data logger were established inside the feedlot for measuring real time changes in the feedlot environment. Milk was collected every day for analysing the productivity of dairy cattle. Blood sample and respiration of dairy cattle were collected once in a week for investigating the physiological response factors. Blood component concentration associated with lipolysis metabolism and milk production showed change during tropical night period. Temperature humidity index (THI) of a specific location inside the feedlot showed continuously high levels.

Relationship between the GVC participation and the productivity in the Chinese Manufacturing Industries (중국 제조업에서 GVC 참여 정도와 위치가 생산성에 미친 영향 실증 분석)

  • Jingbu Wang;Keunyeob Oh
    • Korea Trade Review
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    • v.46 no.3
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    • pp.45-63
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    • 2021
  • This paper investigates the effects of China's participation in global value chains (GVC) on the productivities focusing on the manufacturing industries. In this study, several indicators of participation in global value chains were used. These include GVC participation, forward GVC participation, backward GVC participation and GVC position index. In particular, we used the data obtained from 18 manufacturing industries in China during 15 years from 2000 to 2014. The main results of the analysis are as follows. First, the higher the degree of total participation in GVC, the higher the productivity. This means that with the increase in exports and imports of intermediate goods, productivity has increased through technology spillover effects or competition effects, and so on. Second, the backward participation does not increase the productivities significantly while forward participation leads higher productivity. Third, the productivity improvement effects of GVC participation was larger in the high-tech industries than in the low-tech industries. These results show that GVC participation was helpful for the economic growth of China and the efforts for moving toward upstream production stage in GVC is necessary for the improvement of international competitiveness in Chinese manufacturing industry.