• Title/Summary/Keyword: Primary productivity

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Effect of Nitrogen Applications on the Growth and Primary Production of Soybean Population (질소구배에 따른 대두개체군의 생장 및 일차생산성)

  • Song, Seung-Dal;Seung-Won Yu
    • The Korean Journal of Ecology
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    • v.3 no.1_2
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    • pp.11-16
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    • 1980
  • Growth analytical and primary productivity experiments of soybean populations were conducted with special references to the development of productive structures and environmental conditions of nitrogen levels $(N_1,\; control:\; N_2,\; 6.67gN/\textrm m^2:\; N_3,\;13.34\textrm {gN/m}^2)$. The maximum amounts in LAI for $N_1,\; N_2\; and\; N_3$ stand were 17.3, 19.0 and 18.5; in total standing grops, 1570, 1785 and 1704gDM/$\m^2$; in total net productions, 543, 648 and 636gDM/$\m^2$, respectively. The maximum CGR attanined were 208, 237 and 272 gDM$\m^2$/week, while the mean EU was 2.55, 2.92 and 2.84% N1, N2 and N3, respectively. The total nitrogen standing quantity attained 53.4, 71.8 and 59.8 gN/$\m^2$ at the maximum standing crop period. The net nitrogen absorption rates showed highly significant differences among nitrogen treatments, i.e., 1.34, 10.77 and 13.22 mg/g/day for $N_1,\; N_2\; and \;N_3$ stand, repsectively.

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Studies on the Productivity of Korean White Pine Forest (I) Effects of Temperature, Light and Water Stress on Photosynthesis and Dark Respiration Rates of Leaves (잣나무림(林)의 물질생산력(物質生産力)에 관(関)한 연구(硏究) (I) 엽(葉)의 광합성속도(光合成速度)와 호흡속도(呼吸速度)에 미치는 광(光)․온도(溫度)․수분(水分)의 영향(影響))

  • Han, Sang Sup
    • Journal of Korean Society of Forest Science
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    • v.55 no.1
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    • pp.55-58
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    • 1982
  • This study is to investigate the effects of temperature, light and water deficit on apparent phytosynthesis rate (Pn) and dark respiration rate(Rd) of leaves in the series of studies dealing with primary productivity of korean white pine forest. The results obtained are as follows: 1. The light saturation for Pn occured at about 40 Klux, and light compensation at 1.0 to 1.3 Klux. 2. The Pn of current leaves was highest, and Pn was decreased with increasing leaf age. 3. The Rd on the response of temperature in February was about two times value in all of the temperature ranges as compared with the ones in August. 4. The incipient water stress, above which Pn and Rd declined from 100%, was different for Pn(-10bar). The high water stress required to reduce Pn to nearly 0%, at -24 bar, but Rd was only 43% at -24 bar. 5. The optimum temperature range for Pn showed about 15 to $18^{\circ}C$ in February and 23 to $26^{\circ}C$ in August.

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Primary Productivity and Assimilation Number in the Kyonggi Bay and the mid0eastern coast of Yellow Sea (서해 중동부 연안수역과 경기만에서 일차 생사력과 동화계수에 관한 연구)

  • 강연식;최중기
    • 한국해양학회지
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    • v.27 no.3
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    • pp.237-246
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    • 1992
  • In order to examine controlling factors on primary productivity and assimilation Number of phytoplankton, chlorophyll-a concentrations, light intensity, temperature, salinity and transparency were measured in the Kyonggi Bay and in the mid0eastern coast of Yellow Sea from March 1989 to October 1990. Chlorophyll-a concentration of phytoplankton ranged from 0.91 to 4.30 ug/; in the Kyonggi Bay, and from 0.78 to 4.97 ug/l in the mideastern coast of Yellow Sea. Daily averaged primary productivities and annual primary productivities of phytoplankton ranged from 37.23 to 1104.44 (averaged 361.54) mgC/m$^2$/day, 131.96hC/m$^2$/yr in the mid0eastern coast of Yellow Sea, respectively. Assimilation Number of phytoplankton ranged from 1.47 to 28.28 mgC/mg chl-a/hr in the Kyonggi Bay, and of phytoplankton in the Kyonggi Bay was higher than that of the mid0eastern coast of Yellow Sea. Light utilization efficiencies (a) in the P-I curve ranged from 0.03 to 0.93 [mgC/mg chl-a/hr]/[ue/m$^2$/sec]in the Kyonggi Bay, and from 0.01 to 0.62 [mgC/mg chl-a/hr]/[ue/m$^2$/sec] in the mid-eastern coast of Yellow Sea. Their results indicated that phytoplankton in the Kyonggi Bay utilized light more efficiently than those of the mid0eastern coast of Yellow Sea. The average values of I/SUB k/ were 48.15 ue/m$^2$/sec in the Kyonggi Bay, and 120.37 uE/m$^2$/sec in the mid-eastern coast of yellow Sea. It means the phytoplankton populations in the Kyonggi Bay seem to be adapted to lower light intensity than those of the mid-eastern coast of Yellow sea.

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Imprecise DEA Efficiency Assessments : Characterizations and Methods

  • Park, Kyung-Sam
    • Management Science and Financial Engineering
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    • v.14 no.2
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    • pp.67-87
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    • 2008
  • Data envelopment analysis (DEA) has proven to be a useful tool for assessing efficiency or productivity of organizations which is of vital practical importance in managerial decision making. While DEA assumes exact input and output data, the development of imprecise DEA (IDEA) broadens the scope of applications to efficiency evaluations involving imprecise information which implies various forms of ordinal and bounded data possibly or often occurring in practice. The primary purpose of this article is to characterize the variable efficiency in IDEA. Since DEA describes a pair of primal and dual models, also called envelopment and multiplier models, we can basically consider two IDEA models: One incorporates imprecise data into envelopment model and the other includes the same imprecise data in multiplier model. The issues of rising importance are thus the relationships between the two models and how to solve them. The groundwork we will make includes a duality study which makes it possible to characterize the efficiency solutions from the two models. This also relates to why we take into account the variable efficiency and its bounds in IDEA that some of the published IDEA studies have made. We also present computational aspects of the efficiency bounds and how to interpret the efficiency solutions.

Assessment of the Contribution of Microfinance to Entrepreneurship Development in MOGADISHU

  • Mohamud, Isse Abdikadir;Awale, Abdirahman Abdinur
    • East Asian Journal of Business Economics (EAJBE)
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    • v.4 no.3
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    • pp.18-24
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    • 2016
  • Delivery of microfinance services to operators of small and medium enterprises (SMEs) is increasingly being viewed as a strategic means of assisting growth and development. The purpose of this study was to assess the contribution of microfinance to entrepreneurship development in Mogadishu. Survey research design was adopted and Primary data was collected by using questionnaires. This research study used purposive sampling method to select 120 respondents; but 108 were found usable and analyzed. The data was analyzed using descriptive statistics. This study found the access of microfinance services to the SMEs is poor. This study also found due to the collateral, short term repayment challenges, small and medium businesses are difficult to access loan from microfinance institutions which hinder their entrepreneurship development. In addition to these, this study found that the Microfinance institutions play significance role to the growth and sustainable development of SMEs and also increases the productivity and profitability of small and medium enterprises. This study recommends the guidelines of microfinance institutions to finance SMEs needs to be flexible and microfinance institutions should give technical assistant to the SME to ensure success in the SME sector. The study also suggests access of microfinance services to the SMEs should be facilitated and awareness to microfinance purposes and activities should be created.

Presenteeism and Absenteeism According to Health Problems on Nurses (간호사의 건강문제에 따른 프리젠티즘과 결근율의 관계)

  • Lee, Young-Mi;Jung, Moon-Hee
    • Research in Community and Public Health Nursing
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    • v.19 no.3
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    • pp.459-468
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    • 2008
  • Purpose: The purpose of this study was to examine the presenteeism and absenteeism in relation to the health problems of nurses. Method: Informed consent was provided before study. Data was collected from January 7 to March 6, 2008 by Stanford Presenteeism Scale-13. Data was collected from 3 hospitals in Seoul Gyeonggi area. The response rate of the questionnaires was 96.2%. Incomplete data was analyzed using SPSS program. Results: Shoulder, back and neck pain were the highest reported health problems and primary health Problem of nurses. Impaired presenteeism was ranked in this order: depression or anxiety, cold, and uterus or ovary disorder. Absenteeism was ranked in this order: uterus or ovary disorder, cold, and dermatological problem. Impaired presenteeism was significantly increasing according to the number of health problems. But Absenteeism was not. Presenteeism was significantly different by age, educational level, religion, whether or not the worker lived with their family, marital status, whether or not the worker has children, time spent in the workforce, experience of turnover, shift work, night work, and level of satisfaction with salary. But absenteeism was not significantly different given these criteria. Conclusions: Health problems of nurses can negatively effect the quality of nursing service and productivity at hospital. Therefore the hospital administrator should control the presenteeism and absenteeism through the management of health problems of nurses.

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Using ICT for Mongolia's sustainable development in energy industry

  • Tungalag, Azjargal;Kim, Yun Seon
    • Asia Pacific Journal of Business Review
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    • v.2 no.1
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    • pp.21-52
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    • 2017
  • Nowadays every technology is becoming smarter. Consequently, intensive use of ICT in the whole industries and cities enables a sustainable approach to meet enormous productivity, efficiency, transparency and conservation of natural recourses. Likewise, the role of ICT in terms of controlling, monitoring in the energy industry allows integrating potential renewables, bulk energy conservation and reliable optimized operation in the entire system. In this paper outlines challenging issues in renewable energy integration in Mongolia and proposes potential recommendations and conclusions. The author investigated the main technologies used in energy industry mainly smart grid, challenges and policy aspect in Mongolian energy sector by using the primary and secondary approach with case studies and literature based methodologies. Based on the policy aspect and current implementation of smart grid, the paper tries to address the readiness for the main application and future potential ICT driven applications. Furthermore, it concluded that ICT convergence is demanded to overcome the current vulnerabilities and significant momentum to leave behind by using its potential energy recourses and favorable geographical state. Policymakers may find this study useful, as it answers the question of whether ICT investment can ultimately reduce energy consumption and may aid in future planning. Even tough, in order to develop a smart grid and integrating renewables firstly set an appropriate market structure, ICT will key enabler to make energy system more profitable and sustainable. Regarding the result of this study, ICT deployment contribution is a huge demand for future opportunities energy in Mongolia.

Trophic State and P Loading Analysis for Juam Lake (주암호 영양상태 및 인부하 분석)

  • Bae, Sang-Ok;Lee, Yong-Woon;Lee, Sung-Woo;Chung, Seon-Yong
    • Journal of Environmental Impact Assessment
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    • v.9 no.4
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    • pp.291-300
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    • 2000
  • Juam lake is a major water reservoir for the industrial and agricultural activities as well as the residental life of Kwangju and Chonnam regions. However, the water quality of the lake is getting worse due to a large quantity inflowing to the lake. The excessive growth of algae by the overfertilization may result in water treatment problems and also the interference with desirable water uses of navigation, aesthetics, recreation, and aquatic ecosystem. Thus the purpose of this study is to investigate the species and their amount of planktons in the lake and the relationship between the P loading amount and the chlorophyll-a used as a primary productivity index. The results of the investigation show that (1) the predominant species of algae are Microcystis aeruginosa, Anabaena affinis, Melosira granulata, Synedra acus, and Coelastrum cambricum, (2) the trophic state of the lake can be classified as eutrophic, and (3) there is close relation between the P loading amount and the chlorophyll-a.

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A Study on a Hartmann Test of Optical Mirror for On-Machine Measurement of Polishing machine (광학면 연마기의 OMM을 위한 Hartmann Test 방법 연구)

  • 김옥현;이응석;오창진;김용관
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.1
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    • pp.40-45
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    • 2004
  • Recently, aspheric optical lenses and mirrors, which are harder to manufacture and measure than the conventional spherical ones, are widely used, particularly in electronic fabrication process. Generally, interferometric optical method is used for the measurement of spherical optical surface. However, the interferometric method for aspheric surface measurement is difficult because it needs a precise null corrector and strict environmental conditions such as constant temperature, humidity and vibrations. We have been studied on the manufacturing of aspheric optics to improve the surface profile accuracy and productivity using a corrective polishing process. For the corrective polishing, a practical method of On-Machine Measurement (OMM) is required. For this purpose, an optical OMM system has been studied using the Shach-Hartmann test, which is very robust to the practical polishing environment. The wavefront has been reconstructed from the measured data using the primary aberration polynomial function by the least squares fitting. The measured result of the OMM system shows that the maximum deviation is less than 200 nm for the one of commercial Fizeau interferometer Wyko 6000.

Analysis of forest types and stand structures over Korean peninsula Using NOAA/AVHRR data

  • Lee, Seung-Ho;Kim, Cheol-Min;Oh, Dong-Ha
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.386-389
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    • 1999
  • In this study, visible and near infrared channels of NOAA/AVHRR data were used to classify land use and vegetation types over Korean peninsula. Analyzing forest stand structures and prediction of forest productivity using satellite data were also reviewed. Land use and land cover classification was made by unsupervised clustering methods. After monthly Normalized Difference Vegetation Index (NDVI) composite images were derived from April to November 1998, the derived composite images were used as temporal feature vector's in this clustering analysis. Visually interpreted, the classification result was satisfactory in overall for it matched well with the general land cover patterns. But subclassification of forests into coniferous, deciduous, and mixed forests were much confused due to the effects of low ground resolution of AVHRR data and without defined classification scheme. To investigate into the forest stand structures, digital forest type maps were used as an ancillary data. Forest type maps, which were compiled and digitalized by Forestry Research Institute, were registered to AVHRR image coordinates. Two data sets were compared and percent forest cover over whole region was estimated by multiple regression analysis. Using this method, other forest stand structure characteristics within the primary data pixels are expected to be extracted and estimated.

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