• Title/Summary/Keyword: Ag growth

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Growth and Photocurrent Properties of CdIn2S4/GaAs Single Crystal Thin Film by Hot Wall Epitaxy (Hot Wall Epitaxy 법에 의한 CdIn2S4 단결정 박막의 성장과 광전류 특성)

  • Lee, Sang-Youl;Hong, Kwang-Joon;Park, Jin-Sung
    • Journal of Sensor Science and Technology
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    • v.11 no.5
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    • pp.309-318
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    • 2002
  • A stoichiometric mixture of evaporating materials for $CdIn_2S_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $CdIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $CdIn_2S_4$ single crystal thin films measured with Hall effect by van der Pauw method are $9.01{\times}10^{16}\;cm^{-3}$ and $219\;cm^2/V{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $CdIn_2S_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=2.7116\;eV-(7.74{\times}10^{-4}\;eV)T^2/(T+434)$. The crystal field and the spin-orbit splitting energies for the valence band of the $CdIn_2S_4$ have been estimated to be 0.1291 eV and 0.0248 eV, respectively, by means of the photocurrent spectra and the Hopfield quasi cubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}5$ states of the valence band of the $AgInS_2$/GaAs epilayer. The three photocurrent peaks observed at 10K areascribed to the $A_1$-, $B_1$-, and C1-exciton peaks for n = 1.

Induction of Growth Inhibition and Apoptosis in Human Cancer Cells by a Brown Algae Extract (갈조류 추출물에 의한 인간 암세포 성장 억제 및 세포 사멸 유도)

  • Choo, Kang-Sik;Lee, Hae-Nim;Shin, Seong-Ah;Kim, Hyeong-Jin;Park, Young-Seok;Kim, Sang-Ki;Jung, Ji-Youn
    • Journal of Life Science
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    • v.26 no.5
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    • pp.555-562
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    • 2016
  • In this study, we investigated the effects of Undaria pinnatifida (UP), Petalonia binghamiae (PB) and Punctaria latifolia (PL) extracts on the inhibition of proliferation and apoptosis in human gastric and breast cancer cells. AGS, MDA-MB-231 and SK-BR-3 cells were treated with 0, 50, 100, and 200 μg/ml concentrations of the extracts to determine their anti-proliferative effects, using the MTT assay. The UP, PB and PL extracts inhibited proliferation of AGS, MDA-MB-231 and SK-BR-3 cells in a dose-dependent manner, and the PL extract was found to be the most effective. DAPI staining was also performed to determine changes in the cell nucleus. Further, the AGS, MDA-MB-231 and SK-BR-3 cells were treated with 0, 50, 100, and 200 μg/ml of only the PL extract. DAPI staining showed increased chromatin condensation, which is indicative of apoptosis, in the 200 μg/ml group. The expression of the Bax, Bcl-2, and PARP proteins in AGS, MDA-MB-231 and SK-BR-3 cells treated with the PL extract was also determined by western blot analysis. The expression of Bax (a pro-apoptotic protein) and cleaved-PARP was increased, whereas the expression of Bcl-2 (an anti-apoptotic protein) was decreased compared with the control. These findings indicate that the PL extract may have potential as an alternative anticancer drug and nutraceutical.

Biocompatibility and Histopathologic Change of the Acellular Xenogenic Pulmonary Valved Conduit Grafted in the Right Ventricular Outflow Tract (우심실 유출로에 이식한 무세포화 이종 폐동맥 판막도관의 생체 적합성 및 조직병리학적 변화양상에 대한 연구)

  • 허재학;김용진;박현정;김원곤
    • Journal of Chest Surgery
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    • v.37 no.6
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    • pp.482-491
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    • 2004
  • Background: The xenogenic or allogenic valves after in Vitro repopulation with autologous cells or in vivo repo-pulation after acellularization treatment to remove the antigenicity could used as an alternative to synthetic polymer scaffold. In the present study, we evaluated the process of repopulation by recipient cell to the acellu-larized xenograft treated with NaCl-SDS solution and grafted in the right ventricular outflow tract. Material and Method: Porcine pulmonary valved conduit were treated with. NaCl-SDS solution to make the grafts acellularized and implanted in the right ventricular outflow tract of the goats under cardiopulmonary bypass. After evaluating the functions of pulmonary valves by echocardiography, goats were sacrificed at 1 week, 1 month, 3 months, 6 months, and 12 months after implantation, respectively. After retrieving the implanted valved conduits, histopathologic examination with Hematoxylin-Eosin, Masson' trichrome staining and immunohistochemical staining was performed. Result: Among the six goats, which had been implanted with acellularized pulmonary valved conduits, five survived the expected time period. Echocardiographic examinations for pulmonary valves revealed good function except mild regurgitation and stenosis. Microscopic analysis of the leaflets showed progressive cellular in-growth, composed of fibroblasts, myofibroblasts, and endothelial cells, into the acellularized leaflets over time. Severe inflammatory respon-se was detected in early phase, though it gradually decreased afterwards. The extracellular matrices were regenerated by repopulated cells on the recellularized portion of the acellularized leaflet. Conclusion: The acellularized xenogenic pulmonary valved conuits were repopulated with fibroblasts, myofibroblasts, and endothelial cells of the recipient and extracellullar matrices were regenerated by repopulted cells 12 months after the implantation. The functional integrity of pulmonary valves was well preserved. This study showed that the acellularized porcine xenogenic valved conduits could be used as an ideal valve prosthesis with long term durability.

Effect of $Bio-Silverlite^{(R)}$ on Performance, Weight of Organ, Intestinal Villus and Intestinal Microbial in Broiler Chicks (브로일러 사료에 $Bio-Silverlite^{(R)}$의 첨가가 사양성적, 장기중량, 소장 Villus 및 장내 미생물 성상에 미치는 영향)

  • Kim C.H.;Lim K.C.;Hwang J.H.;Ra C.S.;Pak J.I.
    • Korean Journal of Poultry Science
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    • v.33 no.1
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    • pp.33-39
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    • 2006
  • This study was conducted to investigate the feeding effect of $bio-silverlite^{(R)}$ on growth performance, organ phenomenon and cecum microflora in broiler chicks. The $bio-silverlite^{(R)}$ was made by an ion exchange between illite and $silver(Ag^+)$. There were four treatment groups: negative control group(non-treatment), antibiotic supplement group (positive control), 0.5% $bio-silverlite^{(R)}$ supplment group and 1.5% $bio-silverlite^{(R)}$ supplement group. Total 200 birds was assigned for this five replication tests, allocating 10 birds into each treatment. Experimental diets were formulated on isocalories and isonitrogen for the whole experimental period. Body weight gain was higher in antibiotic supplementation (+C) and $bio-silverlite^{(R)}$ supplement groups(S 0.5% and 51.5%) than the negative control group(-C), and feed efficiency was significantly enhanced with increase of the level of $bio-silverlite^{(R)}$ supplement. The length of small intestine was longer in +C than in -C and $bio-silverlite^{(R)}$ supplement groups (P<0.05), and the weight of small intestine was proportional to the level of $bio-silverlite^{(R)}$ supplement. Crop weight was lower in $bio-silverlite^{(R)}$ supplement group than in -C and +C groups (P<0.05), and the cecum weight was heavier in $bio-silverlite^{(R)}$ supplementation group. Intestinal villi height was longer in 51.5% group at 3 weeks and 6 weeks of age than in -C and +C groups. With the respect of the formation of intestinal microflora, TBC and CBC was not affected by age and feed additive. However, the number of LAB was slightly higher in $bio-silverlite^{(R)}$ supplement group than in -C and +C groups.

Carbon nanotube field emission display

  • Chil, Won-Bong;Kim, Jong-Min
    • Electrical & Electronic Materials
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    • v.12 no.7
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    • pp.7-11
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    • 1999
  • Fully sealed field emission display in size of 4.5 inch has been fabricated using single-wall carbon nanotubes-organic vehicle com-posite. The fabricated display were fully scalable at low temperature below 415$^{\circ}C$ and CNTs were vertically aligned using paste squeeze and surface rubbing techniques. The turn-on fields of 1V/${\mu}{\textrm}{m}$ and field emis-sion current of 1.5mA at 3V/${\mu}{\textrm}{m}$ (J=90${\mu}{\textrm}{m}$/$\textrm{cm}^2$)were observed. Brightness of 1800cd/$m^2$ at 3.7V/${\mu}{\textrm}{m}$ was observed on the entire area of 4.5-inch panel from the green phosphor-ITO glass. The fluctuation of the current was found to be about 7% over a 4.5-inch cath-ode area. This reliable result enables us to produce large area full-color flat panel dis-play in the near future. Carbon nanotubes (CNTs) have attracted much attention because of their unique elec-trical properties and their potential applica-tions [1, 2]. Large aspect ratio of CNTs together with high chemical stability. ther-mal conductivity, and high mechanical strength are advantageous for applications to the field emitter [3]. Several results have been reported on the field emissions from multi-walled nanotubes (MWNTs) and single-walled nanotubes (SWNTs) grown from arc discharge [4, 5]. De Heer et al. have reported the field emission from nan-otubes aligned by the suspension-filtering method. This approach is too difficult to be fully adopted in integration process. Recently, there have been efforts to make applications to field emission devices using nanotubes. Saito et al. demonstrated a car-bon nanotube-based lamp, which was oper-ated at high voltage (10KV) [8]. Aproto-type diode structure was tested by the size of 100mm $\times$ 10mm in vacuum chamber [9]. the difficulties arise from the arrangement of vertically aligned nanotubes after the growth. Recently vertically aligned carbon nanotubes have been synthesized using plasma-enhanced chemical vapor deposition(CVD) [6, 7]. Yet, control of a large area synthesis is still not easily accessible with such approaches. Here we report integra-tion processes of fully sealed 4.5-inch CNT-field emission displays (FEDs). Low turn-on voltage with high brightness, and stabili-ty clearly demonstrate the potential applica-bility of carbon nanotubes to full color dis-plays in near future. For flat panel display in a large area, car-bon nanotubes-based field emitters were fabricated by using nanotubes-organic vehi-cles. The purified SWNTs, which were syn-thesized by dc arc discharge, were dispersed in iso propyl alcohol, and then mixed with on organic binder. The paste of well-dis-persed carbon nanotubes was squeezed onto the metal-patterned sodalime glass throuhg the metal mesh of 20${\mu}{\textrm}{m}$ in size and subse-quently heat-treated in order to remove the organic binder. The insulating spacers in thickness of 200${\mu}{\textrm}{m}$ are inserted between the lower and upper glasses. The Y\ulcornerO\ulcornerS:Eu, ZnS:Cu, Al, and ZnS:Ag, Cl, phosphors are electrically deposited on the upper glass for red, green, and blue colors, respectively. The typical sizes of each phosphor are 2~3 micron. The assembled structure was sealed in an atmosphere of highly purified Ar gas by means of a glass frit. The display plate was evacuated down to the pressure level of 1$\times$10\ulcorner Torr. Three non-evaporable getters of Ti-Zr-V-Fe were activated during the final heat-exhausting procedure. Finally, the active area of 4.5-inch panel with fully sealed carbon nanotubes was pro-duced. Emission currents were character-ized by the DC-mode and pulse-modulating mode at the voltage up to 800 volts. The brightness of field emission was measured by the Luminance calorimeter (BM-7, Topcon).

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Physiological Activity of Sarcodon aspratus Extracts (능이버섯(Sarcodon aspratus) 추출물의 생리활성)

  • 송재환;이현숙;황진국;한정환;노정근;금동혁;박기문
    • Food Science of Animal Resources
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    • v.23 no.2
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    • pp.172-179
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    • 2003
  • This study was carried out to find the preventive medical and therapeutic effects of Sarcodon asparatus on adult disease by employing several biological and biochemical assays. Nitrate scavenging ability(NSA) of Sarcodan asparatus extracts was displayed up to 99.9% at pH 1.2 in a dose-dependent manner. They also had 90.4% electron donating ability(EDA) at the concentration of 0.1 mg/mL. Extracts of Sarcodon asparatus were also able to function as a powerful antioxidant at all concentrations(0.01∼l.0 mg/mL). Furthermore, we observed that 1 mg/mL concentration of the extracts was more powerful than BHT, With respect to fibrolytic activity, Sarcodon asparatus showed 1,843.8 unit/g, which was higher than streptokinase(1,189 unit/g). The inhibitory effects of the extracts on angiotensin converting enzyme, measured by the normal and pretreatment methods, were 53 and 58%, respectively. We also performed cytotoxicity effect of Sarcodon asparatus extracts on a various cancer cell lines. The growth inhibitory effects of the extracts(5.0 mg/mL) on A549, HeLa, AGS, and SK-Hep-1 cells were 78.9, 55.3, 69.0, and 42.5 %, respectively. Interestingly, Sarcodon asparatusextracts induced mutation on Salmonella typhimurium TA98 and TA100 when Ames test was done.

A New Whole Crop Barley Cultivar 'Younghan' with Good Quality, Resistance to Lodging and Viral Disease and High-Yielding (양질 내병 내도복 다수성 청보리 품종 '영한')

  • Park, Tae-Il;Seo, Jae-Hwan;Han, Ouk-Kyu;Kim, Kyeong-Hun;Oh, Young-Jin;Park, Ki-Hun;Choi, Jae-Seong;Park, Jong-Chul;Park, Hyoung-Ho;Kim, Hong-Sik;Kim, Jung-Gon;Song, Tae-Hwa;Kim, Won-Ho;Park, Nam-Geon;Jeung, Jae-Hyun;Ju, Jung-Il;Kim, Soo-Yong;Kim, Dae-Ho
    • Korean Journal of Breeding Science
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    • v.43 no.3
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    • pp.184-189
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    • 2011
  • 'Younghan' (Hordeum vulgare L.), a winter barley for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, Rural Development Administration in 2008. It was derived from a cross between $F_1$['YB3433-3B-5'/'YB3135-3B-2-3'] and 'YB3135-3B-2-3'. 'SB971305-B-B-B-4-4' line was selected for its earliness, resistance to disease and good agronomic characteristics. The promising line showed both high yield and lodging resistance in the yield trials in Iksan in 2004 to 2005, and designated as 'Iksan420'. The line was subsequently evaluated for winter hardiness, earliness, and yield at eight locations throughout Korea for two years from 2007 to 2008 and finally named as 'Younghan'. It has the growth habit of IV, erect plant type, green leaf and thick culm in diameter. Its heading date was April 24, and the maturing date was May 25 in paddy field conditions, which were one day earlier than those of the check cultivar 'Youngyang'. The cultivar 'Younghan' had better winter hardiness, and resistance to lodging and BaYMV than those of the check cultivar did. The average forage dry matter yield of 'Younghan' was approximately 12.0 MT/ha in adapted region. 'Younghan' also showed 8.5% of crude protein content, 27.2% of ADF, and 67.1% of TDN, including higher grade of silage quality for whole crop barley. This cultivar would be suitable for (area with daily minimum temperature in January) above $-8^{\circ}C$ in Korean peninsula.

Induction of Apoptosis in HT-29 Human Colorectal Cancer by Aloin (인간 대장암 세포 HT-29에서 Aloin에 의한 Apoptosis 유도)

  • Yoo, Eun-Seon;Woo, Joong-Seok;Kim, Sung-Hyun;Lee, Jae-Han;Han, So-Hee;Jung, Soo-Hyun;Park, Young-Seok;Kim, Byeong-Soo;Kim, Sang-Ki;Park, Byung-Kwon;Jung, Ji-Youn
    • Journal of Food Hygiene and Safety
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    • v.34 no.5
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    • pp.495-501
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    • 2019
  • Aloin [1,8-Dihydroxy-10-(${\beta}$-D-glucopyranosyl)-3-(hydroxymethyl)-9(10H)-anthracenone], is a natural anthraquinone from aloe. It has been shown to have antioxidant and anticancer effects in various types of human cancer cells, but the anticancer effects of aloin in human colorectal cancer cells HT-29 have not been elucidated. In this study, possible mechanisms by which aloin exerts its apoptotic action in cultured human colorectal cancer HT-29 cells were investigated. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay shows that treatment with aloin (0, 100, 200, 300 and $400{\mu}M$) reduced cell viability in a concentration-dependent manner in HT-29 and showed no effects on cell proliferation in A375SM and AGS cells. In addition, it was confirmed that apoptotic body was significantly increased as shown by 4',6-diamidino-2-phenylindole (DAPI) staining, and increased apoptosis rate by flow cytometry in HT-29 cells treated with aloin (0, 200 and $400{\mu}M$). We confirmed by western blotting that aloin activated Bax (pro-apoptotic), cleaved-poly (ADP-ribose) polymerase (PARP) and caspase-3, -8 and Bcl-2 (anti-apoptotic) were not changed compared with the control. Aloin induced up-regulation of phospho-p38 and down-regulation of phospho-extracellular signal-regulated kinase (ERK)1/2. Therefore, aloin suppressed the growth inhibitory effects by the induction of apoptosis in human colorectal cancer cells and has potential as a cancer preventive medicine.

'Youho', A New Forage Barley Cultivar with Ruminant-Palatable Hood Spike Type and Non-Scatteredness (가축 기호성이 높은 내탈립 삼차망 청보리 신품종 '유호')

  • Park, Tae-Il;Seo, Jae-Hwan;Han, Ouk-Kyu;Kim, Kyeong-Hun;Park, Ki-Hun;Oh, Young-Jin;Choi, Jae-Seong;Park, Jong-Chul;Park, Hyoung-Ho;Kim, Hong-Sik;Kim, Jung-Gon;Song, Tae-Hwa;Kim, Won-Ho;Park, Nam-Geon;Jeung, Jae-Hyun;Ju, Jung-Il;Kim, Soo-Yong;Kim, Dae-Ho
    • Korean Journal of Breeding Science
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    • v.43 no.3
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    • pp.190-195
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    • 2011
  • 'Youho' (Hordeum vulgare L.), a new ruminant-palatable forage barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA in 2008. It was derived from the cross between 'Suwon339' and 'Suwon355'. Among the cross made in 1999, a promising line, SB992047-B-B-B-6-2, showed good characteristics in potential forage yield in the yield trial tested at Iksan from 2005 to 2006. In 2007, it was designated as 'Iksan431' and placed in regional yield trials at eight locations in Korea for two years from 2007 to 2008, and was released as the name of 'Youho'. It has the growth habit of group II, erect plant type, green leaf and hood spike. Its average heading and maturing dates were on Apr. 24 and May 26, respectively, which are similar to check cultivar 'Yuyeon'. 'Youho' also showed weaker winter hardiness, but better resistance to lodging, shattering and BaYMV than those of check cultivar. It showed higher crude protein content, grade of silage quality than those of check cultivar. The average forage dry matter yield in the regional yield trial was about 14.1, $10.9MT\;ha^{-1}$ in upland and paddy field, respectively, which were 1% to 4% lower than that of the check cultivar. This cultivar would be suitable for the area whose daily minimum temperature was above $-8^{\circ}C$ in January in Korean peninsula.

A Study on the Key Factors Affecting Big Data Use Intention of Agriculture Ventures in Terms of Technology, Organization and Environment: Focusing on Moderating Effect of Technical Field (농업벤처기업의 빅데이터 활용의도에 영향을 미치는 기술·조직·환경 관점의 핵심요인 연구: 기술분야의 조절효과를 중심으로)

  • Ahn, Mun Hyoung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.6
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    • pp.249-267
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    • 2021
  • The use of big data accumulated along with the progress of digitalization is bringing disruptive innovation to the global agricultural industry. Recently, the government is establishing an agricultural big data platform and a support organization. However, in the domestic agricultural industry, the use of big data is insufficient except for some companies in the field of cultivation and growth. In this context, this study identifies factors affecting the intention to use big data in terms of technology, organization and environment, and also confirm the moderating effect of technical field, focusing on agricultural ventures which should be the main entities in creating innovation by using big data. Research data was obtained from 309 agricultural ventures supported by the A+ Center of FACT(Foundation of AgTech Commercialization and Transfer), and was analyzed using IBM SPSS 22.0. As a result, Among technical factors, relative advantage and compatibility were found to have a significant positive (+) effect. Among organizational factors, it was found that management support had a positive (+) effect and cost had a negative (-) effect. Among environmental factors, policy support were found to have a positive (+) effect. As a result of the verification of the moderating effect of technology field, it was found that firms other than cultivation had a moderating effect that alleviated the relationship between all variables other than relative advantage, compatibility, and competitor pressure and the intention to use big data. These results suggest the following implications. First, it is necessary to select a core business that will provide opportunities to generate new profits and improve operational efficiency to agricultural ventures through the use of big data, and to increase collaboration opportunities through policy. Second, it is necessary to provide a big data analysis solution that can overcome the difficulties of analysis due to the characteristics of the agricultural industry. Third, in small organizations such as agricultural ventures, the will of the top management to reorganize the organizational culture should be preceded by a high level of understanding on the use of big data. Fourth, it is important to discover and promote successful cases that can be benchmarked at the level of SMEs and venture companies. Fifth, it will be more effective to divide the priorities of core business and support business by agricultural venture technology sector. Finally, the limitations of this study and follow-up research tasks are presented.