• Journal of Microbiology and Biotechnology
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• 제23권4호
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• pp.539-544
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• 2013

The effects of culture depth (2-10 cm) and cell density on the growth rate and biomass productivity of Chlorella sp. XQ-200419 were investigated through the use of a self-designed open circular pond photobioreactor-imitation system. With increases in culture depths from 2 to 10 cm, the growth rate decreased significantly from 1.08 /d to 0.39 /d. However, the biomass productivity only increased slightly from 8.41 to 11.22 $g/m^2/d$. The biomass productivity (11.08 $g/m^2/d$) achieved in 4 cm culture with an initial $OD_{540}$ of 0.95 was similar to that achieved in 10 cm culture with an initial $OD_{540}$ of 0.5. In addition, the duration of maximal areal productivity at a 4 cm depth was prolonged from 1 to 4 days, a finding that was also similar to that of the culture at a 10 cm depth. In both cases, the initial areal biomass densities were identical. Based on these results and previous studies, it can be concluded that the influence of culture depth and cell density on areal biomass productivity is actually due to different areal biomass densities. Under suitable conditions, there are a range of optimal biomass densities, and areal biomass productivity reaches its maximum when the biomass density is within these optimal ranges. Otherwise, biomass productivity will decrease. Therefore, a key factor for high biomass productivity is to maintain an optimal biomass density.

• International Journal of Aeronautical and Space Sciences
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• 제2권1호
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• pp.103-109
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• 2001

Productivity enhancement program of wind tunnel testing has begun at Korea Aerospace Research Institute Low Speed Wind Tunnel (KARI LSWT). A previous test record of a canard airplane model was adopted to examine the current status of wind tunnel testing efficiency. The time consumed to perform testing activities from the model preparation to data collection was broken down and the results were compared with those of the recent Boeing low speed test result. The efforts to improve the wind tunnel productivity consisted of the installation of mini crane underneath of test section, fabricating lift device for image fairings, model configuration changing rigs and the modifications of external balance system. Time reductions for changing strut interface platform and installation of image fairings. These effects showed more than 70% improvement over the previous test time. Integration of the new and modified systems will improve productivity of wind tunnel testing in KARI LSWT.

• Biotechnology and Bioprocess Engineering:BBE
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• 제3권2호
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• pp.112-114
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• 1998

For enhancement of cis,cis-muconate productivity from benzoate, catechol 1,2-dioxygenase (C12O) which catalyzes the rate-limiting step (catechol conversion to cis,cis-muconate) was cloned and expressed in recombinant Pseudomonas putida BCM114. At higher benzoate concentrations (more than 15 mM), cis,cis-muconate productivity gradually decreased and unconverted catechol was accumulated up to 10 mM in the cae of wild-type P. putida BM014, whereas cis,cis-muconate productivity continuously increased and catechol was completely transformed to cis,cis-muconate for P. putida BCM114. Specific C12O activity of P. putida BCM114 was about three times higher than that of P. putida BM014, and productivity was enhanced more than two times.

• 기술사
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• 제27권6호
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• pp.85-93
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• 1994

For the continuous development of the manufacturing company, selp-helpㆍdiligence of the individual members of the organization and cooperation system of the sub-department process of the manufacture must operate under rationality. Moreover, perpetual and reasonable improvement on productivity should be focused on. Improvement on productivity implies raising $\ulcorner$output / input$\lrcorner$ ratio, and this does not only implies simple increase of the level of output. Therefore under the theoretical principle, Which is designed to increase the ratio of $\ulcorner$output / input$\lrcorner$ -economically select the relevant $\ulcorner$methodology$\lrcorner$. When rational improvement on productivity $\ulcorner$techniques$\lrcorner$ are properly applied with this methodology, calculated result will come out. The ultimate aim of improving quality does not mean simply reducing the percentage of the defects, but means improving the quality of products, for customer satisfaction. Thus recognize this, we have to contribute to the national economy growth through the enhancement of added value of individual company by $\ulcorner$improvement on quality and productivity, and reduction of the cost$\lrcorner$, $\ulcorner$improvement program on quality and productivity$\lrcorner$ shouldn't be just the parading formality. We can expect the economy result, these are applied to the learning essence and the principle of the improvement.

• 인터넷정보학회논문지
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• 제8권5호
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• pp.151-160
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• 2007

다양한 분석 정보를 추출하여 저장하는 데이터웨어하우스는 기업의 마케팅 및 의사결정 지원을 위해 사용된다. 그러나 데이터웨어하우스는 분산되어 저장된 대규모의 데이터를 통합하기 때문에 처리 시간과 비용이 증가하며 오류 발생의 위험이 높다. 따라서 개발생산성의 향상 및 비용을 절감하기 위해 본 연구에서는 생산성, 프로세스 품질, 데이터 품질의 영역에서 프로세스 측정지표를 설계하여 제안한다. 또한 측정 지표를 이용하여 프로세스를 평가하고 평가결과를 분석하여 개발생산성의 향상과 프로세스가 개선됨을 보인다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.624-627
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• 2002

A study on machining electrode for LEO(Light Emitted Diode) mold with shaped end-mill is presented. The electrode machining by shaped end-mill has been used for maximizing the productivity in manufacture of semiconductor mold. However, it has not been researched systematically for many difficulties such as the making of shaped end-mill, generation of tool path due to distinctive tool geometry, and so on. Tool path is generated on the shaped end-mill geometry and cutting force to provide accurate and efficient machining of electrode. The verification program can drive enhancement of productivity, selecting cutting conditions from experiment function of cutting force. Also, compensation of tooting and machina error can make the electrode accurate by modifying tool path. Therefore, the research on machining with shaped end-mill can contribute to enhancement of accuracy and productivity in building semiconductor mold.

• 한국환경과학회지
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• 제8권5호
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• pp.575-586
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• 1999

From the environmental aspects, primary productivity of phytoplankton plays the most improtant role in enhancement of marine culture oyster production. This study may be divided into two branches; one is estimation of maximum oyster meat production per unit facility(Carrying Capacity) under the present enviromental conditions in Kamak Bay, the other is improvement of carrying from increase of primary productivity by changing the environmental conditions that cause not ot form an unfavorable environment such as the formation of oxygen deficient water mass using the eco-hydrodynamic model. By simulation of three-dimensional hydrdynamic model and ecosystem model, the comparison between observed and computed data showed good agreement. The results of sensitivity analysis showed that phytoplankton maximum growth rate was the most important parameter for phytoplankton and dissolved oxygen. The estimation of mean primary productivity of Wonpo, Kamak, Pyongsa, and Kunnae culture grounds in Kamak Bay during culturing period were 3.73gC/$m^2$/d, 2.12gC/$m^2$/d, 1.98gC/$m^2$/d, and 1.26gC/$m^2$/d, respectively. Under condition not ot form the oxygen deficient water mass, four times increasing of pollutants loading as much as the present loading from river increased mean primary productivity of whole culture grounds to 4.02gC/$m^2$/d. Sediment N, P fluxes that allowed for 35% increasing from the present conditions increased mean primary productivity of whole culture grounds to 3.65gC/$m^2$/d. Finally, ten times increasing of boundary loadings from the present conditions increased mean primary productivity of whole culture grounds to 3.95gC/$m^2$/d. The maximum oyster meat production per year and that of unit facility in actual oyster culture grounds under the present conditions were 6,929ton and 0.93ton, respectively. This 0.93ton/unit facility is considered to be the carrying capacity in study area, and if the primary productivity is increased by changing the environmental conditions, oyster production can be increased.

• Journal of Construction Engineering and Project Management
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• 제7권3호
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• pp.39-55
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• 2017

Preeminent performance of construction industry are unattainable with poor productivity resulting in time and cost over runs. Enhancement in productivity cannot be achieved without identifying and analyzing factors that adversely affect productivity. The objective therefore is to propose a productivity analysis model to quantify the probability of effect of factors influencing productivity by using fuzzy logic incorporated with relative importance index method, for various types of construction projects. To achieve this objective, a questionnaire survey was carried out targeting respondents of Indian construction industry, from four distinct projects, namely, residential, commercial, infrastructure and industrial projects. Based on questionnaire administered, the relative importance and ranks of factors demonstrated using relative importance index method. Probability assessment model to analyze productivity was then developed by using Fuzzy Logic Toolbox of MATLAB. The applicability of the proposed model was tested in seven construction projects and the probability of impact of factors on productivity evaluated. The results of application of model in the construction firms infers that the most contributing factor groups for most of the projects were discerned to be manpower, motivation and time group.

• 한국정밀공학회지
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• 제19권10호
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• pp.187-194
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• 2002

A study on machining electrode for LED (Light Emitted Diode) mold with shaped end-mill is presented. The electrode machining by shaped end-mill has been used for maximizing the productivity in manufacturing semiconductor mold. However, it has not been researched systematically for many difficulties such as the making of shaped end-mill, generation of tool path due to distinctive tool geometry, and so on. Tool path is generated on geometry of the shaped end-mill and cutting force to provide accurate and efficient machining of electrode. The verification program can drive enhancement of productivity, selecting cutting conditions from experiment function of cutting force. Also, compensation of tooling and maching error can make the electrode accurately by modifying tool path. Therefore, the research on machining with shaped end-mill can contribute to enhancement of accuracy and productivity in building semiconductor mold.

• 대한안전경영과학회지
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• 제19권4호
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• pp.283-290
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• 2017

In knowledge information society entering global unlimited competition era, our middle and small sized companies are the base of national and enterprise competitiveness and core base of national economy as an origin of jobs. The competitiveness of middle and small sized companies is so important to decide the level of the competitiveness of the whole industries, but the gap from big sized company is much low in comparison with advanced countries from angles of important factors of enterprise growth, productivity and technological competitiveness, so, it's urgent to improve the competitiveness through productivity enhancement. The purpose of this research is to do a positive study on effects of learning organization management outcomes of middle and small sized company on enterprise productivity among various types of outcome brought for strengthening of enterprise competitiveness. It confirmed learning organization has functions and usefulness as a management tool bringing positive effects on enterprise productivity through the Productivity improvement.