• Journal of the Daesoon Academy of Sciences
• /
• v.20
• /
• pp.193-222
• /
• 2009

There is no place in the scriptures of Daesoonjinrihoe(大巡眞理會) where Indian philosophy is directly discussed. The philosophies dealt with in Daesoon thought are mostly those of Christianity, Confucianism, Buddhism, and Taoism. Of course, the thoughts that are not widely known and those that are not considered to be worth comparing with the Daesoon thought must have been omitted. It seems that Indian philosophy and Daesoon thought have considerable similarity. First of all, the two philosophies are rooted in religion. True, there is no dearth of religious philosophies in the East, for instance, Confucianism and Taoism, and yet comparing Daesoon thought and Indian philosophy is significant because they both presuppose a theistic paradigm. At the core of the two perspectives, there is personal God, i.e., Isvara or Gucheon Sangje (九天上帝), upon whom human beings and the world absolutely depend as his creation. Unlike traditional Christian theology, the two philosophies are alike in being indifferent to proving the existence of the deity and focusing on his form and role. In this article, the author try to examine the meaning of the four tenets of Daesoonjinrihoe(Eumyanghapdeok 陰陽合德, Shininjohwa 神人調化, Haewonsangsaeng 解冤相生, Dotongjingyeong 道通眞境) from the perspective of Indian philosophy in general, Purusa-sukta of Rig-veda, theistic Upanisads, and Ramanuja's Visistadvaita(限定不二論) in particular. Before making up the main subject, the author inquires into the characteristics of Ultimate Reality in Daesoon thought and Indian philosophy.

• Journal of Mechanical Science and Technology
• /
• v.16 no.7
• /
• pp.986-998
• /
• 2002

Flow and spray characteristics are critical factors that affect the performance and exhaust emissions of a direct injection diesel engine. It is well known that the swirl control system is one of the useful ways to improve the fuel consumption and emission reduction rate in a diesel engine. However, until now there have only been a few studies on the effect of flow on spray. Because of this, the relationship between the flow pattern in the cylinder and its influence on the behavior of the spray is in need of investigation. First, in-cylinder flow distributions for 4-valve cylinder head of DI (Direct Injection) Diesel engine were investigated under steady-state conditions for different SCV (Swirl Control Valve) opening angles using a steady flow rig and 2-D LDV (Laser Doppler Velocimetry). It was found that swirl flow was more dominant than that of tumble in the experimented engine. In addition, the in-cylinder flow was quantified in terms of swirl/tumble ratio and mean flow coefficient. As the SCV opening angle was increased, high swirl ratios more than 3.0 were obtained in the case of SCV -70° and 90°. Second, spray characteristics of the intermittent injection were investigated by a PDA (Phase Doppler Anemometer) system. A Time Dividing Method (TDM) was used to analyze the microscopic spray characteristics. It was found that the atomization characteristics such as velocity and SMD (Sauter Mean Diameter) of the spray were affected by the in-cylinder swirl ratio. As a result, it was concluded that the swirl ratio improves atomization characteristics uniformly.

• International Journal of Automotive Technology
• /
• v.6 no.1
• /
• pp.1-8
• /
• 2005

Recently, the HSDI (High Speed Direct Injection) diesel engine has been spotlighted as a next generation engine because it has a good potential for high thermal efficiency and fuel economy. This study was carried out to investigate the in-cylinder flow characteristics generated in a HSDI diesel engine with a 4-valve type cylinder head. The four kinds of cylinder head were manufactured to elucidate the effect of intake port geometry on the in-cylinder flow characteristics. The steady flow characteristics such as coefficient of flow rate $(C_{f})$, swirl ratio (Rs), and mass flow rate (m,) were measured by the steady flow test rig and the unsteady flow velocity within a cylinder was measured by PIV. In addition, the in-cylinder flow patterns were visualized by the visualization experiment and these results were compared with simulation results calculated by the commercial CFD code. The steady flow test results indicated that the mass flow rate of the cylinder head with a short distance between the two intake ports is $13\%$ more than that of the other head. However, the non-dimensional swirl ratio is decreased by approximately $15\%$. As a result of in-cylinder flow characteristics obtained by PIV and CFD calculation, we found that the swirl center was eccentric from the cylinder center and the position of swirl center was changed with crank angle. As the piston moves to near the TDC, the swirl center corresponded to the cylinder center and the velocity distribution became uniform. In addition, the results of the calculation are in good agreement with the experimental results.

• The Journal of the Acoustical Society of Korea
• /
• v.35 no.3
• /
• pp.183-191
• /
• 2016

A systematic development process for the low noise FEAD (Front End Accessory Drive) system is presented by combining CAE (Computer Aided Engineering) and the experimental rig test. In the estimation of the belt drive noise, two main difficulties arise from the high non-linearity due to the stick-slip contacts on the interfaces of the belt and pulleys, and the interaction of the belt drive system with the powertrain rotational parts. In this work, a recently developed analysis method of the belt drive has been employed considering powertrain rotational dynamics. As results, it shows good correlation with the vehicle tests in various operational modes. The established model has been employed to validate the new design improving the stick-slip noise of the problematic FEAD system. Furthermore, the best proposal of FEAD system in terms of functionality [NVH (Noise, Vibration and Harshness), fuel economy, cost. etc.] has been suggested in the concept design stage of new engine through this presented methodology.

• Applied Chemistry for Engineering
• /
• v.21 no.6
• /
• pp.684-688
• /
• 2010

Biodiesel produced from the reaction of methanol and triglyceride which is the main component of animal fats and vegetable oils is known for remarkable lubricity. In this study, the lubricity of 3 kinds of biodiesel came from vegetable oils such as soybean oil, palm oil, and perilla oil and 2 kind of biodiesel which were produced from beef tallow and pork lard were analyzed using HFRR (High frequency reciprocating rig). In HFRR test result, the lubricity of perilla and soybean's biodiesel was higher than other biodiesels. After analysis of biodiesel components by GC-MS and determination of the lubricity of pure biodiesel components using HFRR, it was found that a higher olefin content and long alkyl chaining biodiesel had an excellent lubricity property.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.24 no.9
• /
• pp.1185-1194
• /
• 2000

The characteristics of intake port flow and engine performance with swirl ratio variance in a turbocharged D.I. diesel engine were studied in this paper. The intake port flow is important factor which have influence on the engine performance and exhaust emission because the properties in the injected fuel depend on the combustion characteristics. Through these experiments it can be expected to satisfy performance and emission by optimizing the main parameters; the swirl ratio of intake port, injection timing and compression ratio. The swirl ratio for ports was modified by hand-working and measured by impulse swirl meter. For the effects on performance and emission, the brake torque and brake specific fuel consumption were measured by engine dynamometer, NOx and smoke were measured by gas analyzer and smoke meter. The results of steady flow test are as follows; as the valve eccentricity ratio are closed to cylinder wall, the flow coefficient and swirl intensity are increased. Also we realized that there is a trade-off that the increase of swirl ratio decreases mean flow coefficient and increases the Gulf factor. And the optimum parameters to meet performance and emission through engine test are as follows; the swirl ratio 2.43, injection timing BTDC 13oCA and compression ratio 15.5.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.2
• /
• pp.241-248
• /
• 2013

In this study, bearings were developed for a high-power propulsion motor operating in inclined operation conditions through a simulation and similitude-experimental methods using commercial rotating machinery dynamics analysis software. The developed journal bearing is electrically insulated and has low thermal conductivity because each part is connected with 2-4 -mm-thick epoxy plates. To realize an appropriate oil thickness, an oil lift system is adopted, and a half separated structure is applied to ensure the feasibility of maintaining very heavy components. This study discusses some of the key design aspects of sleeve bearing design for high-torque and low-speed propulsion motor applications. Furthermore, the conditions of variable slope tests are examined to prevent oil leakage from the bearing lip seal on the test rig.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.21 no.7
• /
• pp.948-961
• /
• 1997

The effects of intake port eccentricity and a partition between the two intake ports on the incylinder swirl characteristics in a 4 valve diesel engine having the two intake ports, one is a helical intake port and the other is a tangential intake port, were investigated by using the impulse swirl meter(ISM) in a steady flow test rig. Mean flow coefficient ( $C_{f(mean)}$, swirl ratio ( $R_{s}$) and the mass flowrate through the two intake ports with and without intake port partition were measured. The results showed that the characteristics of in-cylinder swirl ratio formed by a 4-valve cylinder head were largely affected by valve eccentricity ratio ( $N_{y}$) and the existence of an intake port partition between the two intake ports. Mean flow coefficient ( $C_{f(mean)}$) increases and swirl ratio ( $R_{s}$) decreases in case of being the partition between the two intake ports. And also the mass flowrate through the tangential intake port is 19.0% and 7.7% more than that of the helical intake port in case of the two intake ports with and without partition respectively.ively.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.8 no.1
• /
• pp.38-43
• /
• 2004

The study was performed to understand combustion characteristics of the slinger combustor. Liquid fuel is discharged radially outwards through injection holes drilled in the high speed rotating shaft. The spray test was peformed to verify atomizing characteristics with variation of fuel nozzle rotational speed by using PDPA system. SMD was measured at different RPM and values are 70$\mu\textrm{m}$ at 5,000RPM rpm, 60$\mu\textrm{m}$ at 10,000RPM and 40$\mu\textrm{m}$ at 20,000RPM. In the results, we found out that SMD is grown smaller with increasing rotational speed. In KARI combustion test facility, Ignition and combustion tests were performed by using combustor test rig. In the test results, ignition and combustion efficiency were improved according to increasing rotational speed. The measured radial temperature distribution at the combustor exit shows stable and fairly good distribution.

• The Korean Journal of Physiology and Pharmacology
• /
• v.1 no.6
• /
• pp.797-808
• /
• 1997

Nitric oxide (NO) has been 3mown as a mediator of nonadrenergic, noncholinergic inhibitory neurotransmitter in intestinal smooth muscles. It has been suggested that NO donor such as sodium nitroprusside (SNP) produces relaxation of smooth muscle via activation of guanylate cyclase and elevation of cGMP levels. We have therefore investigated the effects of NO, using SNP, on muscle tension in the longitudinal smooth muscle of guinea-pig ileum. The possible role of cGMP was also investigated as well as the involvement of $K^+$ channel on SNP-induced inhibitory effect. The results are summarized as follows; high KCI-or CCh-activated contractions were inhibited by SNP in a concentration-dependent manner. 8-Br-cGMP also showed a similar effect in that of SNP TEA (1 mM) significantly reduced the SNP-induced inhibitory effect. SNP-induced effect was forther reduced by the presence of 10 mM TEA. On the other hand, 4-AP (0.1 mM), glibenclamide $(10\;{\mu}M)$ and apinain $(0.1\;{\mu}M)$ showed little effects on SNP-induced relaxation. Zaprinast significantly potentiated the SNP-induced inhibitory effect in all ranges. ODQ also significantly decreased the SNP-induced inhibitory effect. Pretreatment with CPA $(10\;{\mu}M)$ slightly reduced the SNP-induced inhibitory effect. From the above results, both effect mediated by NO and cGMP might be responsible for the activation of $Ca^{2+}$-activated $K^+$ channel by SNP in guinea-rig ileum. And this $K^+$ channel activation by SNP also contributes to the SNP-induced membrane hyperpolarization and relaxation.