• STI Policy Review
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• v.8 no.1
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• pp.23-40
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• 2017

This article provides a comprehensive review of the entrepreneurial university concept and its place and role in the triple helix of university, industry, and government. This is increasingly important because stake-holders' expectations towards universities are growing; this growth in turn leads to increased pressure on universities to move beyond their traditional roles and models towards taking responsibility for economic development, large scale basic education and targeted further education and the development of value from research. These expectations provide opportunities for universities, but impose threats on the existing models and practices. It further elaborates on implications for university management, departments, faculty members and supporting organizations. Moreover it reflects on the meaning of the entrepreneurial university for stakeholders, i.e., university boards, regional and national policy and administrative bodies, funding agencies, the business community, university ranking institutions and the global university community overall. Recent literature on entrepreneurial universities is incomplete and mostly focused on the commercialization of research, technology transfer and the third mission of universities. The article expands the predominant thinking about entrepreneurial universities and gives a broader structured definition. Eventually the article shows the need for STI policy to intervene and measures for developing entrepreneurial universities further.

• Journal of Mechanical Science and Technology
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• v.16 no.6
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• pp.776-784
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• 2002

We have performed experimental studies for the improvements of pneumatic brake systems of freight trains. Currently, most of the freight trains operated by the Korean National Railroad have either empty-load or diaphragm type brake systems. In this study, appropriate methods that the air pressure characteristics in both type of brake systems are in accordance with each other have been investigated. We have also performed running tests using a 30 car-train set to design optimum capacity of a quick release valve. The test results show that the quick release valve is considerably effective in shortening the release time of the diaphragm type brake system. In the case of a normal brake application, the diaphragm type brake system with the quick release valve reduces the release time to 34% of that of the system without the quick release valve. This release time is almost equivalent to that of the empty-load type brake system. Accordance of braking performance in different types of brake systems in a train set is expected to prevent wheel flats and to reduce maintenance costs.

• Journal of the Korean Vacuum Society
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• v.14 no.4
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• pp.180-185
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• 2005

The possibility of generation of the vacuum scale using the vapour pressure of water was evaluated. The range of vacuum from 3.3 kPa to 101.3 kPa was corresponds the vapour pressure of water in the temperature range from $25^{\circ}C$ to $100^{\circ}C$ The measured values of the vapour pressure of water were agreed within the deviation of $5\%$ comparing to reference value. This result shows the vapour pressure of water can be used as an secondary reference of the vacuum scale. Moreover it shows the thermo-dynamical properties such as, triple point, temperature-pressure curve of a material have a applicability in the vacuum scale as a reference in corresponding range of vacuum.

• Journal of the Korean Society of Visualization
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• v.18 no.3
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• pp.116-121
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• 2020

In this study, a single-phase analysis of droplet slug with different contact angles was performed based on the visualization of experimental results. Droplet slug - flowing between gases in a hydrophobic mini channel - moves with a triple contact line without a gas liquid film on the wall. The results show that the rotational flow inside the droplet occurred; this was compared and verified with the results of two-phase analysis. The pressure field shows pressure rise at the front and rear ends. The effective length - the section that satisfies the laminar flow condition - became shorter as the droplet velocity increased. The Choi's correlation for the effective length agrees with this analysis results with a slight difference. This difference is judged as the difference in the contact angle of the slug model.

• Transactions of the KSME C: Technology and Education
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• v.1 no.2
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• pp.167-177
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• 2013

The use of mechanical anastomosis coupler instead of sutures has been increasing in microvascular anastomosis surgery. However, non-biodegradable anastomosis coupler has problems such as not only inflammatory reaction but also remaining permanently in operation wound. Therefore, we fabricated biodegradable anastomosis coupler using injection molding process to overcome the limitation of non-biodegradable anastomosis coupler. In various injection molding process conditions, the shrinkage was calculated with different cylinder temperatures and injection molding pressures and anastomotic strength was measured. As a result, changes in shrinkage hole part larger than the pin part. In addition, the shrinkage in the cylinder at higher temperatures increase. However, the higher the injection pressure, shrinkage tends to decrease, respectively. In-vitro degradation behavior of PCL anastomotic coupler evaluated for 12 weeks, water uptake was increased and molecular weight was accompanied by a reduction in mass of the biological degradation and reduction of anastomotic strength was confirmed. However, decreased levels of anastomotic strength enough to exceed the requirements of preclinical surgery, PCL microvascular anastomosis coupler suitable candidate materials that could identify.

• Fire Science and Engineering
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• v.31 no.5
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• pp.63-69
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• 2017

This study describes the development of a long-distance hose for ultra-high pressure operation, which can be used in conjunction with an ultra-high pressure pump and can be effectively applied to the fire suppression of high-rise buildings and a long, large tunnels. Also, it has phosphorescent properties, which can help to secure the withdrawal route of the fire-fighters when they are threatened by the fire. We developed an ultra-high pressure hose aiming at a pressure of 3 MPa and a flow rate of 2000 lpm and developed an ultra-high pressure fire hose that can withstand this very high pressure by using a double jacket, triple polyurethane coating and warf (Wp) of 52. In order to ensure the performance of the developed ultra-high pressure hose, its structure, appearance, leakage at high pressure, length and elongation were inspected by a certified certification agency, who also subjected it to a peeling test, friction test, breaking pressure test and free fall test. Also, it was studied in addition to the luminescent high-pressure hose for fire-fighting. In the phosphorescence test, the luminance measurement value was more than the reference value of the luminance test after 40 minutes, which confirmed that its performance was satisfactory for fire-fighting products. In the future, if such an ultra-high pressure fire hose were commercialized and applied in the field, it could contribute to securing improved fire suppression and safer exit from fires, as compared to the fire hoses currently used in the suppression of fires in skyscraper buildings and long tunnels.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.303-307
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• 2007

This clinical experience reports the effect of wood and fire acupoints therapy on a hypertensive patient. Wood acupoint indicates Jing point in yin channel or Shu point in yang channel. Fire acupoint is Jing in yin channel or Jing in yang channel among the five acupoints of Jing, Xing, Shu, Jing and He. The patient was treated with indicated acupoints of 7 channels: lung, large intestine, spleen, pericardium, triple warmer, heart and liver, for 5 weeks. In case of necessity, another acupoints were added with wood and fire acupoints. After 5 weeks treatment, the blood pressure improved by 125/80 which is in normal level. This result suggests that wood and fire acupoints therapy is effective in the treatment of hypertension.

• Progress in Superconductivity and Cryogenics
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• v.5 no.1
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• pp.76-80
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• 2003

A contractible heat pipe is designed and tested to improve cooling performance of conduction cooled superconducting magnet. When the heat pipe temperature drops below the triple point temperature, heat pipe working fluid freezes to create low pressure. From this moment the heat pipe does net work any more (OFF state) and it just works as a heat leak path when the temperature of the first stage is higher than that of the second stage. Considering small cooling capacity of the second stage around 4.2 K, the conduction loss is not negligible. Therefore, the contractible heat pipe, made of a metal bellows and copper tubes, was considered to eliminate the conduction loss. Nitrogen and argon are as working fluid of heat pipe. The copper block is cooled down with these heat pipe and the cooling performance for each heat pipe is compared. At off state, the bellows is contracted due to the low pressure of heat pipe and the evaporator section of the heat pipe is detached about 3 mm from the second stage cold head of the cryocooler. In this way, we tan eliminate the conduction loss through the heat pipe wall.

• Journal of Environmental Science International
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• v.10 no.1
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• pp.79-84
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• 2001

To assess resistance of transgenic tobacco plants which overexpress superoxide dismutase (SOD) and ascorbate peroxidase (APX) in chloroplasts to water stress, changes in leaf water potential, turgor potential, stomatal conductance and transpiration rate were measured. Leaf water potential in all plants remained high up to day 4 after withholding water but thereafter decreased markedly. In spite of a remarkable decrease in leaf water potential, some of transgenic plants maintained higher turgor potential compared with control plant on day 12. In particular, the transgenic plant expressing MnSOD showed an outstanding maintenance in turgor pressure by osmotic adjustment throughout the experiment, resulting in high stomatal conductance and transpiration rate. However, among transgenic plants, osmotic potential was reduced more effectively in multiple transformants such as the double transformant expressing both MnSOD and APX, and the triple transformant expressing CuznSOD, MnSOD and APX than single transformants. Consequently, further research is needed to get general agreement on the tolerance of transgenic plants to water stress at different growth stages for each transgenic plant.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.110-110
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• 1999

Polyvinylidenefluoride (PVDF) is most used in piezoelectric polymer industry. Electrode effect on the electrical properties of PVDF has been investigated. al has been used due to fair adhesion for PVDF. Work function of metal plays an important role on the electrical properties of ferroelectrics for top and /or bottom electrode. However, Al has much lower work function than Pt or Au and so leakage current of Al/PVDF/Al may be large. Pt or Au has not been used for electrode of PVDF system due to poor adhesion. PVDF irradiated by Ar+ ion beam with O2 environment takes good adhesion to inert metal. Contact angle of PVDF to triple distilled water was reduced from 75$^{\circ}$ to 31$^{\circ}$ at 1$\times$1015 Ar+/cm2. Working pressure was 2.3$\times$10-4 Torr and base pressure was 5$\times$10-6 Torr. Pt was deposited by ion beam sputtering and thickness of pt film was about 1000$\AA$. in previous study, enhancing adhesion of Pt on PVDF was shown. in this study, effect of electrode on PVDF will be represented.