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The Analysis for the determinant Factors on the Outcome of Technology Innovation Among Small and Medium Manufacturers (중소 제조기업의 기술혁신 성과 결정 요인에 관한 분석)

  • You, Yen-Yoo;Roh, Jae-Whak
    • The Journal of Society for e-Business Studies
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    • v.15 no.1
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    • pp.61-87
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    • 2010
  • This study is based on the analysis of technology innovation performance for Inno-biz. The primary purposes of this study are to help the government formulate Inno-biz related supporting policies and improve the fitness of evaluation models for Inno-biz. In this study the definition of "the outcome of technology innovation" includes technology competitiveness changes, technology forecasting as well as the outcome of technology innovation. For this analysis, 55 independent variables were used and categorized into ability of technology innovation, ability of commercialization, and ability of technology management. The results indicate that all three variable groups have positively influenced the outcome of technology innovation. Especially ability of technology innovation is highly related to technology competitiveness and business in future. The ability of commercialization enhances technology competitiveness and predictability in major business indexes; however it doesn't influence business performance in a short-term period. The ability of technology management enables businesses to forecast technology changes, but doesn't effect short-term business outcomes.

Effect of High Pressure on Polarographic Parameters of 1-(2-Pyridylazo)-2-naphthol and 4-(2-Pyridylazo)-resorcinol in Methanol-Water Mixed Solution (메탄올-물 混合溶媒中에서 1-(2-Pyridylazo)-2-naphthol과 4-(2-Pyridylazo)-resorcinol의 폴라로그래프법적 파라미터에 미치는 壓力의 影響)

  • Heung Lark Lee;Zun Ung Bae;Jong Hoon Yun
    • Journal of the Korean Chemical Society
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    • v.29 no.3
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    • pp.197-204
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    • 1985
  • The dependence of polarographic parameters on pressure and temperature for the reduction of 2.0 ${\times}\;10^{-4}$M 1-(2-pyridylazo)-2-naphthol (PAN) and 5.0 ${\times}\;10^{-4}$M 4-(2-pyridylazo)-resorcinol(PAR) in buffered methanol-water mixed solution at the dropping mercury electrode, has been discussed. In this experiment the temperature is varied from 25$^{\circ}C$ to 35$^{\circ}C$ and the pressure is ranging from 1 atmosphere to 1,800 atmospheres. The reduction half-wave potentials are shifted to the more positive potentials with increase in pressure. The diffusion currents of two depolarizers become considerably larger with increase in pressure from 1 atmosphere to about 1,000 atmospheres but are getting smaller above 1,000 atmospheres. The slopes of log plot become much larger with increase in pressure, which indicates the more irreversible reduction. The reduction currents of two depolarizers are found to be diffusion controlled over all pressure ranges. The linear relationships between diffusion current and the concentration of two depolarizers are good agreement over all pressure ranges (1 atm∼1,800atm.).

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Catalytic Hydrogenation of Unsaturated Organic Compounds by Rutheniumhydridonitrosyl Complexes (Rutheniumhydridonitrosyl 착물을 이용한 불포화 유기화합물의 수소화 반응)

  • Park, Mi Young;Kim, Young Joong;Cho, Ook Jae;Lee, Ik Mo
    • Journal of the Korean Chemical Society
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    • v.40 no.6
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    • pp.445-452
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    • 1996
  • Catalytic hydrogenation of ketones and aldehydes by RuH(NO)$L_3$ ($L_3$: $PPh_3$, PhP($CH_2CH_2PPh_2$)$_2$(etp)) was investigated to examine the reaction mechanism and the competence of hydridonitrosyl complexes as catalysts for organic synthesis. RuH(NO)$L_3$ showed catalytic activity for the hydrogenation and the activities of catalysts were dependent on the steric and electronic factors. The less the steric demands of the substrates become, the more activity the catalysts show. For the electronic effect, the more the partial positive charge on the carbonyl carbon atom in ketones becomes and the more the double bond character of carbonyl group in aldehydes becomes, the more active the catalysts are. These results reflect the difference of reaction mechanisms of two substrates, ketones and aldehydes. Catalytic activities of RuH(NO)(etp) and RuH(NO)($PPh_3$)$_3$ in the presence of extra $PPh_3$ toward hydrogenation showed the existence of a reaction pathway accompanied with the change of the bonding modes of NO ligand. The roles of excess $PPh_3$ change with increase of the mole ratio of $PPh_3$ to catalysts; prevention of ligand dissociation from comlexes → bases → ligands. The activity of RuH(NO)(etp) was lower than that of RuH(NO)($PPh_3$)$_3$ toward the hydrogenation of the same substrates mainly due to the structural difference. These catalysts showed the selectivity toward olefin hydrogenation over carbonyl groups in the competitive reaction.

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Mössbauer Study of Silver Nanoparticle Coated Perovskites La0.7Sr0.3Co0.3Fe0.7O3-δ (LSCF) (은(Ag) 나노입자가 코팅된 페롭스카이트 La0.7Sr0.3Co0.3Fe0.7O3-δ의 Mössbauer 분광연구)

  • Uhm, Young-Rang;Rhee, Chang-Kyu;Kim, Chul-Sung
    • Journal of the Korean Magnetics Society
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    • v.22 no.2
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    • pp.37-41
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    • 2012
  • The Ag nanoparticles attached $La_{0.7}Sr_{0.3}Co_{0.3}Fe_{0.7}O_{3-{\delta}}$ (LSCF) perovskites were prepared by plasma method. The Ag nanoparticles with size of several nanometers deposited from the Ag target were coated on the surface of LSCF powders with size range from 0.2 to 3 ${\mu}m$. The agglomeration of Ag particles annealed at $800^{\circ}C$ under inert gas of Ar were rarely observed. The inter-diffusion between surface Ag and core LSCF is effectively strong to prevent aggregation of Ag nanoparticles. The wave number of FT-IR spectra for LSCF were largely shifted as the concentration of Ag on LSCF up to 2.11 wt.%. The ionic states of irons in LSCF were measured by M$\ddot{o}$ssbauer spectroscopy. The small amount of $Fe^{4+}$ ions are converted to $Fe^{3+}$ ions after Ag nanopartcles were coated on LSCF.

Moderating Effect and Mediation Effect of Social Support in the Relationship between Art Therapist's Job Stress and Psychological Burnout

  • Song, Shin-Young;Moon, Kyung-Rye
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.2
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    • pp.149-156
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    • 2020
  • In this paper, we propose the moderating effects and mediation effects of social support on the relationship between art therapists' job stress and psychological burnout. Based on the previous studies, this study set up four types of variables: 1) independent variable, 2) moderating variable, 3) mediation variable, and 4) dependent variable. Job stress was identified as an independent variable, social support was identified as both a moderating variable and mediation variable, and psychological burnout was identified as a dependent variable. To empirically conduct this study, a total of 200 questionnaires were distributed to art therapists. Consequently, a total of 150 survey responses were collected. The survey results are as follows. First, there were not differences in job stress, psychological burnout, and social support due to personal environmental factors. This included career, employment type and working hours. Second, the result showed a high-level of correlation among job stress, psychological burnout, and social support. Third, social support was found to have a moderating effect on the relationship between the art therapists' job stress and psychological burnout. Forth, social support was found to have a moderating effect on the relationship between the art therapists' job stress and psychological burnout.

Temporal and Spatial Variations of Temperature and Salinity around Ganjeol Point in the Southeast Coast of Korea (한국 남동해 간절곶 주변해역의 열염구조와 시공간적 변동 특성)

  • Choo, Hyo-Sang;Jang, Duck-Jong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.5
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    • pp.474-485
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    • 2014
  • Temporal and spatial variations of temperature and salinity around Ganjeol Point during January, April, August and November 2011 were studied using the data from CTD observations and temperature monitoring buoys deployed at 20 stations in the southeast coast of Korea. Temperature and salinity were nearly homogeneous through the whole depth by mixing of the seawater in spring and winter related to the sea surface cooling. Stratification induced by the river runoff and the bottom cold water was clear in summer. In autumn, sea water had vertical mixing initiated from surface layer and weak stratification at the middle and bottom layers. Low temperature and high salinity emerged throughout the year near Ganjeol Point, which inferred from turbulent mixing and upwelling by its topographical effect. Major periods of 1/4~1.4 day temperature fluctuations were recorded for the most part of the stations. According to the cross spectral density analysis, high coherence and small time lag for temperature fluctuation between layers were shown at Ganjeol Point. However, those features at the northen area of Hoeya river were opposed to Ganjeol Point. From analyses, thermohaline structure and its fluctuation around Ganjeol Point were characterized into those three parts, the south of Ganjeol Point, Ganjeol Point and the north of Ganjeol Point.

Behavioral Analysis of Silt Protectors in Seawater Using the Mass-Spring Model (질량-스프링 모델을 이용한 해수 중 오탁방지막 거동해석)

  • Lee, Choon-Woo;Kim, Ok-Sam;Shin, Hyun-Chool;Hwang, Doo-Jin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.2
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    • pp.194-199
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    • 2017
  • When sea tide and wave velocity change, the behavior of silt protectors underwater changes, and a hydraulic force exceeding the anchor wave force is applied. In this study, the movement mechanism of a silt protector has been analyzed using the mass-spring method. The initial position of the silt protector was in the Jindo area near Gwangpo Port (742-1, Gyupori, Chongdo-myeon, Jindo-gun, Jeonnam, Korea). The tension required to exceed the holding power of the anchor was 0.05 m/s at 318 sec., 0.15 m/s at 77 sec., 0.25 m/s at 43 sec., and 0.3 m/s at 37 sec.. As the anchor started to move from the sea floor and the tide speed increased to 0.01 m/s, anchor movement start time shortened by an average of 11.2 sec.. Compared with when tide was the only affecting factor, the silt protector and anchor were found to have moved 19.7 % at 0.1 m/s, 7.6 % at 0.15 m/s, 5.8 % at 0.2 m/s, 4.3 % at 0.25 m/s and 2.8 % at 0.3 m/s, showing an increase. When wave effect was added to the tide, anchor movement started when the flow rate was slow 7.6 % of the time. With a high flow velocity, anchor movement started without any significant difference less than 4.3 % of the time. When tide speed exceeded 0.13 m/s and the direction of the waves matched, the silt protector was not able to perform due to collisions with surrounding sea structures. When installing a silt protector, the fluid flow situation and the silt protector situation must be carefully analyzed using the mass-spring method to apply the result found in this study.

Occurrence of Leaf Spot Caused by Stemphylium lycopersici on Cirsium setidens in Korea (Stemphylium lycopersici에 의한 고려엉겅퀴 점무늬병의 발생)

  • Choi, Hyo-Won;Kim, Seok Gu;Hong, Sung Kee;Lee, Young Kee;Lee, Jae Guem;Kim, Hyo Won;Lee, Eun Hyeong
    • The Korean Journal of Mycology
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    • v.44 no.3
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    • pp.201-205
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    • 2016
  • In August 2015, leaf spot symptoms were observed on Korean gondre thistle (Cirsium setidens) in Youngwol, Korea. During the early stage, the symptoms appeared as one or more small gray-brown to brown spots on plant leaves. The spots showed extensive enlargement over time and eventually became large dark brown to black lesions on the whole leaf. Stemphylium species were consistently isolated from affected leaves. All isolates were identified as S. lycopersici, S. solani, or S. xanthosomatis based on morphological and cultural characteristics. The isolates were confirmed as S. lycopersici based on a multilocus sequence analysis using the ribosomal internal transcribed spacer (ITS) region, elongation factor 1, GAPDH (glyceraldehyde-3-phosphate dehydrogenase), and the noncoding region between the vacuolar membrane ATPase catalytic subunit A gene and a gene involved in vacuolar biogenesis. Pathogenicity was tested by spore suspension inoculation on wounded or unwounded gondre leaves. The lesions were observed on inoculated leaves within 3 days after inoculation, regardless of wound. To our knowledge, this is the first report of the leaf spot on gondre thistle caused by S. lycopersici in Korea or elsewhere.

Analysis of Degradation Behaviors of Geomembrane by Accelerated Test under UV Exposure Conditions (자외선 노출조건 하에서 가속시험에 의한 지오멤브레인의 분해거동 해석)

  • Park, Yeong Mog;Khan, Belas Ahmed;Jeon, Han Yong
    • Polymer(Korea)
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    • v.37 no.1
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    • pp.5-14
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    • 2013
  • In this paper the effect of UV (ultraviolet) exposure on HDPE (high density polyethylene)-smooth and f-PP (flexible polypropylene) geomembranes is evaluated under UVB-313 (ultraviolet wavelength 290-315 nm) exposure. Tensile property, melt flow index (MFI), oxidation induction time (OIT), both standard-OIT and high pressure-OIT and Fourier transform infrared spectroscopy/attenuated total reflectance (FTIR/ATR) results are discussed. Although tensile properties of the exposed geomembrane samples remained unchanged, the depletion of antioxidants was found higher for f-PP than for HDPE geomembrane. Arrhenius model by extrapolation was used on the data to predict the antioxidant lifetime to a typical site temperature of $20^{\circ}C$. There was no significant difference between the MFI value of the virgin and UV exposed HDPE geomembrane samples but a decrease in MFI was found in f-PP geomembrane that signifies that crosslinking has occurred. From FTIR spectra, the small peak (near $1750\;cm^{-1}$) observed in the spectrum of UV exposed sample corresponds to a carbonyl (C=O) linkage, which suggests that oxidation has occurred in the polymer structure, and another new band for f-PP between 3100 and $3500\;cm^{-1}$ is attributed to a hydroxyl bond and/or hydroperoxide bond.

Digitalization of the Nuclear Steam Generator Level Control System (증기발생기 수위조절 시스템의 디지탈화)

  • Lee, Yoon-Joon;Lee, Un-Chul
    • Nuclear Engineering and Technology
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    • v.25 no.1
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    • pp.125-135
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    • 1993
  • The safe and efficient operation of nuclear plants is recognized to be accomplished through the application of plant automation using digital technology, which is one of main targets of the next generation nuclear plants. For plant level automation, it is first required that each major subsystem be digitalized, and the steam generator water level control system is discussed in this study. The transfer functions between inputs and the level are derived by employing the thermal hydraulic model of the steam generator and are applied to the analysis of the current three-element control system. Since the control scheme in this study includes the steam generator itself as a process plant, the system order is high and the numerical instability arises in digitalizing. Together with this, the unreliability of the feedwater feedback signal at low power level leads to the proposal of a two-element control system with a proper digital controller. The digital PI controller developed for this system has the initial power adaptive gain and integration time constant. And it makes the overall system response satisfy the stability and other necessary control specifications simultaneously. Since the two-element control system using this controller depends on the initial power only, it is simple to define and it shows a similar level response behavior to that of its corresponding analog system.

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