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The Effect of Patent Citation Relationship on Business Performance : A Social Network Analysis Perspective (특허 인용 관계가 기업 성과에 미치는 영향 : 소셜네트워크분석 관점)

  • Park, Jun Hyung;Kwahk, Kee-Young
    • Journal of Intelligence and Information Systems
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    • v.19 no.3
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    • pp.127-139
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    • 2013
  • With an advent of recent knowledge-based society, the interest in intellectual property has increased. Firms have tired to result in productive outcomes through continuous innovative activity. Especially, ICT firms which lead high-tech industry have tried to manage intellectual property more systematically. Firm's interest in the patent has increased in order to manage the innovative activity and Knowledge property. The patent involves not only simple information but also important values as information of technology, management and right. Moreover, as the patent has the detailed contents regarding technology development activity, it is regarded as valuable data. The patent which reflects technology spread and research outcomes and business performances are closely interrelated as the patent is considered as a significant the level of firm's innovation. As the patent information which represents companies' intellectual capital is accumulated continuously, it has become possible to do quantitative analysis. The advantages of patent in the related industry information and it's standardize information can be easily obtained. Through the patent, the flow of knowledge can be determined. The patent information can analyze in various levels from patent to nation. The patent information is used to analyze technical status and the effects on performance. The patent which has a high frequency of citation refers to having high technological values. Analyzing the patent information contains both citation index analysis using the number of citation and network analysis using citation relationship. Network analysis can provide the information on the flows of knowledge and technological changes, and it can show future research direction. Studies using the patent citation analysis vary academically and practically. For the citation index research, studies to analyze influential big patent has been conducted, and for the network analysis research, studies to find out the flows of technology in a certain industry has been conducted. Social network analysis is applied not only in the sociology, but also in a field of management consulting and company's knowledge management. Research of how the company's network position has an impact on business performances has been conducted from various aspects in a field of network analysis. Social network analysis can be based on the visual forms. Network indicators are available through the quantitative analysis. Social network analysis is used when analyzing outcomes in terms of the position of network. Social network analysis focuses largely on centrality and structural holes. Centrality indicates that actors having central positions among other actors have an advantage to exert stronger influence for exchange relationship. Degree centrality, betweenness centrality and closeness centrality are used for centrality analysis. Structural holes refer to an empty place in social structure and are defined as efficiency and constraints. This study stresses and analyzes firms' network in terms of the patent and how network characteristics have an influence on business performances. For the purpose of doing this, seventy-four ICT companies listed in S&P500 are chosen for the sample. UCINET6 is used to analyze the network structural characteristics such as outdegree centrality, betweenness centrality and efficiency. Then, regression analysis test is conducted to find out how these network characteristics are related to business performance. It is found that each network index has significant impacts on net income, i.e. business performance. However, it is found that efficiency is negatively associated with business performance. As the efficiency increases, net income decreases and it has a negative impact on business performances. Furthermore, it is shown that betweenness centrality solely has statistically significance for the multiple regression analysis with three network indexes. The patent citation network analysis shows the flows of knowledge between firms, and it can be expected to contribute to company's management strategies by analyzing company's network structural positions.

Vertical Profiles of CO2 Concentrations and CO2 Storage in Temperate Forest in Korea (한국 활엽수림의 이산화탄소 농도의 연직구조와 저류항)

  • Thakuri, Bindu Malla;Kang, Minseok;Chun, Jung Hwa;Kim, Joon
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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    • 2013.11a
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    • pp.23-24
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    • 2013
  • Micrometeorological fluxes measured over a tall forest in a complex terrain are difficult to interpret. $CO_2$ storage often makes significant contributions to net ecosystem exchange of $CO_2$ (NEE) in early morning and during nighttime due to calm and stable conditions. We measured the above-canopy $CO_2$ flux along with its concentration profiles at eight levels within and above the canopy to evaluate $CO_2$ storage term. Our question is whether or not the $CO_2$ storage term can be estimated accurately from a single level measurement of $CO_2$ concentration in a complex terrain. Our objectives are (1) to document vertical profiles of $CO_2$ concentration and (2) to compare the diurnal and seasonal variations of $CO_2$ storages estimated from single and multi-level $CO_2$ concentration data. Seasonally averaged Diurnal variations of $CO_2$ concentration ranged from 398 to 455 ppm near the forest floor at 0.1 m whereas they ranged from 364 to 395 ppm at 40 m in the atmosphere. The diurnal variation of vertical profiles of $CO_2$ concentration shows very interesting features with season. At all eight levels, diurnal variation of $CO_2$ concentration showed little change in winter. In spring, the diurnal variations of $CO_2$ concentration at 8 levels showed three distinct groups of layers with height: the first layer: 0.1m (near surface), second layer: 1.0 m and 4.0m (below canopy) and the third layer: 7.4m to 40.7 m (near canopy and above). In summer, these three groups of layers were further separated with larger variations whereas such distinction became smaller in fall. The diurnal variation of $CO_2$ concentration in the first three layers near surface always showed higher concentration with larger variability. Typically, $CO_2$ concentration showed peaks in early morning and in the evening. After the evening peak, $CO_2$ concentration gradually increased except for those near the surface (i.e., 0.1, 1.0 and 4.0 m) where the concentrations actually decreased. We suspect that this could be attributed to the drainage flow of $CO_2$ along the hill slope from the headwater to downstream, which is not taken into account for net ecosystem $CO_2$ exchange. In comparison to the results of other studies, the distinct and different vertical structures of $CO_2$ concentrations observed at our site may be due to complex terrain and weak turbulent mixing under calm conditions at the site. The annual mean of diurnal variation of $CO_2$ storage flux from single level ranged from -0.6 to $0.9{\mu}mol\;m^{-2}s^{-1}$ and from multi-level from -1.2 to $1.0{\mu}\;{\mu}mol\;m^{-2}s^{-1}$. When compared against the results from the multi-level concentrations, the storage flux estimated from a single-level concentration was generally adequate except for specific hours near sunrise and sunset. Further details and their implication will be discussed in the presentation.

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Anaerobic Reductive Dechlorination of Tetrachloroethylene (PCE) in Two-in-series Semi-continuous Soil Columns (반연속 흐름 2단 토양 컬럼에서의 사염화 에틸렌(PCE)의 혐기성 환원탈염소화)

  • Ahn, Young-Ho;Choi, Jeong-Dong;Kim, Young;Kwon, Soo-Youl;Park, Hoo-Won
    • Journal of Soil and Groundwater Environment
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    • v.11 no.2
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    • pp.68-76
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    • 2006
  • Anaerobic reductive dechlorination of tetrachloroethylene (PCE) to ethylene was investigated by performing laboratory experiments using semi-continuous flow two-in-series soil columns. The columns were packed with soils obtained from TCE-contaminated site in Korea. Site ground water containing lactate (as electron donor and/or carbon source) and PCE was pumped into the soil columns. During the first operation with a period of 50 days, injected mass ratio of lactate and PCE was 620:1 and incomplete reductive dechlorination of PCE to cis-DCE was observed in the columns. However, complete dechlorination of PCE to ethylene was observed when the mass ratio increased to 5,050:1 in the second operation, suggesting that the electron donor might be limited during the first operation period. Dechlorination rate of PCE to cis-DCE was $0.62{\sim}1.94\;{\mu}mol$ PCE/L pore volume/d and $2.76\;{\mu}mol$ cis-DCE/ L pore volume/d for that for cis-DCE to ethylene, resulting that net dechlorination rate in the system was 1.43 umol PCE/L pore volume/d. During the degradation of cis-DCE to ethylene, the concentration of hydrogen in column groundwater was $22{\sim}29\;mM$ and $10{\sim}64\;mM$ for the degradation of PCE to cis-DCE. These positive results indicate that the TCE-contaminated groundwater investigated in this study could be remediated through in-situ biological anaerobic reductive dechlorination processes.

Plasma-Assisted Molecular Beam Epitaxy of InXGa1-XN Films on C-plane Sapphire Substrates (플라즈마분자선에피탁시법을 이용한 C-면 사파이어 기판 위질화인듐갈륨박막의 에피탁시 성장)

  • Shin, Eun-Jung;Lim, Dong-Seok;Lim, Se-Hwan;Han, Seok-Kyu;Lee, Hyo-Sung;Hong, Soon-Ku;Joeng, Myoung-Ho;Lee, Jeong-Yong;Yao, Takafumi
    • Korean Journal of Materials Research
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    • v.22 no.4
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    • pp.185-189
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    • 2012
  • We report plasma-assisted molecular beam epitaxy of $In_XGa_{1-X}N$ films on c-plane sapphire substrates. Prior to the growth of $In_XGa_{1-X}N$ films, GaN film was grown on the nitride c-plane sapphire substrate by two-dimensional (2D) growth mode. For the growth of GaN, Ga flux of $3.7{\times}10^{-8}$ torr as a beam equivalent pressure (BEP) and a plasma power of 150 W with a nitrogen flow rate of 0.76 sccm were fixed. The growth of 2D GaN growth was confirmed by $in-situ$ reflection high-energy electron diffraction (RHEED) by observing a streaky RHEED pattern with a strong specular spot. InN films showed lower growth rates even with the same growth conditions (same growth temperature, same plasma condition, and same BEP value of III element) than those of GaN films. It was observed that the growth rate of GaN is 1.7 times higher than that of InN, which is probably caused by the higher vapor pressure of In. For the growth of $In_xGa_{1-x}N$ films with different In compositions, total III-element flux (Ga plus In BEPs) was set to $3.7{\times}10^{-8}$ torr, which was the BEP value for the 2D growth of GaN. The In compositions of the $In_xGa_{1-x}N$ films were determined to be 28, 41, 45, and 53% based on the peak position of (0002) reflection in x-ray ${\theta}-2{\theta}$ measurements. The growth of $In_xGa_{1-x}N$ films did not show a streaky RHEED pattern but showed spotty patterns with weak streaky lines. This means that the net sticking coefficients of In and Ga, considered based on the growth rates of GaN and InN, are not the only factor governing the growth mode; another factor such as migration velocity should be considered. The sample with an In composition of 41% showed the lowest full width at half maximum value of 0.20 degree from the x-ray (0002) omega rocking curve measurements and the lowest root mean square roughness value of 0.71 nm.

Case Study on the Instability of the Slopes in Unsaturated Residual Soils Considering the Rainfall Characteristics (강우특성을 고려한 불포화 잔적토 비탈면의 붕괴사례 연구)

  • Nam, Samheon;Lee, Younghuy;Oh, Seboong
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.1
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    • pp.45-53
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    • 2015
  • This study has obtained Soil Water Retention Curve (SWRC) of the unsaturated soil from the volumetric pressure plate extractor test and the triaxial compression tests was also conducted. By using the rainfall data measured in the site the seepage analysis of unsteady flow was performed with the program of SEEP/W in Geostudio 2007 and stability of the slope was analyzed with SLOPE/W program. Results of analyses show that shear strength of the unsaturated soil increases with the increase of matric suction. And it was also found that the net volumetric stress and the apparent cohesion increased with the matric suction. The seepage analysis of rainfall represents that the increasing rate of negative pore pressure at the zone of large negative pore pressure is appeared to be high even though lower rainfall intensity, but this tendency declines with ground depth. The stability analysis of slope was carried out for the actual plane of failure with the data representing the field condition. The factor of safety thus calculated was about unity (1.0) or just below, which means that the adopted method of analysis is in good agreement with the field condition.

A Colored Workflow Model for Business Process Analysis (비즈니스 프로세스 분석을 위한 색채형 워크플로우 모델)

  • Jeong, Woo-Jin;Kim, Kwang-Hoon
    • Journal of Internet Computing and Services
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    • v.10 no.3
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    • pp.113-129
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    • 2009
  • Abstract Corporate activities are composed of numerous working processes and during the working flow, various business processes are being created and completed simultaneously. Enterprise Resources Planning (ERP) makes the working process simple, yet creates more complicated work structure and therefore, there is an absolute need of efficient management for business processes. The workflow literature has been looking for efficient and effective ways of rediscovering and mining workflow intelligence and knowledge from their enactment histories and event logs. As part of studies to analyze and improve the process, the concepts of 'Process Mining', 'Process re-discovery', 'BPR (Business Process Reengineering)' have appeared and the studies for practical implementation are proactively being done. However, these studies normally follow the approach throughout data warehousing for log data of process instances. It is very hard for these approaches to reflect user's intention to the rediscovering and mining activities. The process instances designed based on the consideration of analysis can make groupings effectively and when the analysis demand of user changes within the analysis domain can also reduce the cost of analysis. Therefore, the thesis proposes a special type of workflow model, which is called a colored workflow model, that is extended from the ICN (information control net) modeling methodology by reinforcing the concept of colored token. The colored tokens represent the conceptual types of constraints and criteria that can be used to classifying and grouping the workflow intelligence and knowledge extracted from the corresponding workflow models' enactment histories and event logs. Through the runtime information of process instances, it makes possible to analyze proactive and user-oriented process with the goal of deriving business knowledge from the beginning of process definition.

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Measurement of $\textrm{CO}_2$ Concentration and Leaf Area Index for Crop Photosynthesis Model in Sweet Pepper (단고추의 작물 광합성 모델을 위한 $\textrm{CO}_2$ 농도와 엽면적지 수 측정)

  • Lee, Beom-Seon;Chung, Soon-Ju;Jang, Hong-Gi
    • Journal of Bio-Environment Control
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    • v.8 no.3
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    • pp.192-201
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    • 1999
  • This study was aimed to introduce the measurement of $CO_2$ concentration and leaf area index in the phytotron for predicting the effect of CO.E, light and leaf area index on the instantaneous photosynthetic rate of sweet pepper with the existing ASKAM model. Measurements were made in 2 semi-closed phytotron compartments in which three different $CO_2$ concentrations were applied at random. Plants were grown on containers with circulating nutrient solution at 21$^{\circ}C$ and 80-95% relative humidity. The model estimates crop net $CO_2$ uptake for short time intervals during the day based on short-term data of daily radiation, temperature and $CO_2$ concentration. During the photosynthesis measurements, $CO_2$ concentrations in both compartments and in the basement were measured every minute. This was also done for the flow of pure $CO_2$ into the compartment, global radiation, photosynthetic active radiation inside the compartment, temperature and relative humidity. Crop growth models summarize our knowledge on crop behavior and have as such a wide range of applications in analysis, crop management and thus as a farm management tool.

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A Study on the Numerical Modeling of the Fish Behabior to the Model Net - Examination on the Validity of a Numerical Model of Fish Behavior - (모형그물에 대한 어군행동의 수직 모델링에 관한 연구 - 어군행동을 나타내는 수치 모델의 타당성 검토 -)

  • Lee, Byoung-Gee;Lee, Dae-Jae;Chang, Ho-Young
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.31 no.4
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    • pp.326-339
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    • 1995
  • In this paper, the validity of the numerical model of fishes' behavior presented in our earlier paper was examined by the whiteness test on the residual of numerical model and by the comparison between experiment and simulation on several indexes represented by fishes' swimming characteristics. The validity of the numerical model was proved statistically by means of the whiteness test of the residual. The similarity was confirmed by comparison between experiment and simulation for the swimming trajectory of fishes, the mean distance of individual from wall, the mean swimming speed and the mean distance between the nearest individuals. These results suggest that the behavior of fishes according to the flow speed in three-dimensional space can be estimated partially by the numerical model presented in our earlier paper. However, a long-term approach to improve the modeling technique on the behavior of fishes may be needed before applying the numerical model presented in our earlier paper to real fishing ground.

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Effect of EC and pH of Nutrient Solution on the Growth and Quality of Single-Stemmed Rose in Cutted Rose Production Factory (절화장미 수경재배시 배양액의 농도와 pH가 생육과 품질에 미치는 영향)

  • Lee Hye Jin;Yang Eun-Young;Park Keum-Soon;Lee Yong-Beom;Bae Jong Hyang;Jeon Kyung Soo
    • Journal of Bio-Environment Control
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    • v.13 no.4
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    • pp.258-265
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    • 2004
  • The experiment was conducted to investigate the effect of EC and pH of nutrient solution on the growth and quality of the single-stemmed rose grown in a rose factory installed with hydroponic system. The growth and quality of the single-stemmed rose were not significantly different from each other with the EC of the nutrient solutions $1.0\~3.5dS{\cdot}m^{-1}$, which resulted in concluding high concentration of the nutrient solution was not necessary. The optimum range of the EC for single-stemmed rose was $1.5\~2.0dS{\cdot}m^{-1}$ considering plant growth, photosynthetic and transpiration rates. The optimum range of the pH for good plant growth without any visible physiological disorder was $4.0\~6.0$. Therefore, to keep the pH of the nutrient solution for rose low compared to other plants was beneficial for plant growth and uptake of the mineral ions.

PILOT SCALE FISH PRODUCTION IN WATER RECYCLING SYSTEM (순환여과식 사육수정화 재사용방법에 의한 Pilot 규모의 어류양식시험)

  • KIM In-Bae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.13 no.4
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    • pp.195-206
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    • 1980
  • Fish were grown in a water recycling rearing system consisting of a filter system, of which the area is about $30\;m^2$ and the volume of filter gravels is about $15\;m^3$, 6 rearing and 2 supplementary tans about $7\;m^2$ of surface area each. The results for 180 days from April 18 to October 14,1980 are summarized as following: One rearing tank was used for main experiment stocked with an equal number, and weight of each Israeli strain and $F_1$, hybrid between this strain and Korean local strain of common carp. Gross total production was 461 kg with a net production of 395 kg, and the Israeli strain grew to about 8 times initial weight and the hybrid about 6 times. Based on an analysis of results of the above mentioned main experiment and the other miscellaneous fish grown in the remaining tanks, it was considered to be feasible to implement a commercial production in this system by improving parts of the system and adding a number of the units. A special problem seems to be an adoption of more effective aeration device when fish loading increases. A solid waste removal system was deviced by use of by-pass flow ana this system worked very efficiently in view of supply water economy. A serious problem encountered in this experiment was heavy outbreaks of the gill-fluke, Dactylogyrus sp. which was relatively easily eradicated with Dipterex or DDVP treatment in the first trials, but later on strains which were resistant to any of these chemicals appeared.

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