• Proceedings of the KSME Conference
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• 2001.11b
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• pp.946-951
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• 2001

This experimental study is to investigate the intermittent spray characteristics of a pintle nozzle. High speed camera used in this expreiment with 9000fps. The factor, which controls the diesel spray, is the Injection pressure, ambient pressure and ambient temperature. In this paper, experiments were conducted free spray for the ambient pressure(3, 4, 5Mpa), nozzle Injection pressure(10, 14, 18MPa) and ambient temperature(293, 473K). With the higher opening pressure, the spray tip velocity and spray penetration increases while the spray angle decreases, On the other hand, With the higher ambient pressure, the spray angle increase while the spray tip penetration and spray tip velocity decrease. also, With the higher ambient temperature, the spray penetration decrease while the spray angle decrease.

• The Korean Journal of Pain
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• v.10 no.2
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• pp.235-240
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• 1997

Hemifacial spasm is a distressing condition characterized by involuntary, intermittent, unilateral twitching of, all or parts, of the muscles innervated by facial nerve. This ailment is most common among middle-aged women. Neither causative agent nor reliable treatment has been established because etiology of idiopathic hemifacial spasm has remained undefined to date. This report describes two cases of hemifacial spasm treatment by injection of Botulinum toxin. An injection of Botulinum toxin provided relief of hemi facial spasm. Botulinum toxin therapy is an effective and convenient treatment of hemifacialspasm.

• Korean Journal of Veterinary Research
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• v.42 no.1
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• pp.123-130
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• 2002

To investigate the cardiopulmonary and anesthetic effects of propofol in dogs, experimental dogs were randomly divided into 4 groups (propofol infusion anesthesia, P/INF, propofol intermittent anesthesia, P/INTER, propofol induction anesthesia, P/ISO, thiopental Na induction anesthesia, T/ISO) and monitored analgesic and anesthetic effects, recovery time, body temperature, heart rate, mean arterial pressure, respiratory rate, systolic and diastolic pressure. In all groups, apnea was not observed. In the P/INF group, the respiratory rate(RR) was slightly decreased, but in the P/INTER group, RR was increased and shallowing. In the groups of P/ISO and T/ISO, the respiratory rate was decreased. Heart rate(HR) was increased after induction anesthesia in all groups, but gradually decreased. Mean arterial pressure(MAP) was decreased after injection anesthesia in the groups of P/INF and P/INTER. In the groups of P/ISO and T/ISO, however, MAP was slightly increased. Systolic and diastolic arterial pressure were gradually decreased after induction anesthesia, but not significantly. In the groups of P/INF and P/ISO, recovery time was shorter than the groups of P/INTER and T/ISO. In all groups, body temperature of animals was decreased gradually according to time but no significant changes were observed. Propofol injection doesn't make the complete loss of responses of animals, especially, in the P/INTER group. In the P/INF group, deep pain was present until the end of anesthetic period. During recovery period, any other side effects except incoordination were not monitored. The present study suggested that infusion anesthesia was superior to intermittent anesthesia as injection anesthetic agent, and propofol was better than thiopental Na as induction anesthetic agent.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.2
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• pp.42-49
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• 1991

This study is to investigate the dispersion characteristics of diesel fuel spray in the initial stage of the beginning of the injection under the condition of room temperature and atmospheric pressure. It is difficult to analyse that the diesel fuel spray in diesel engine has unsteady intermittent spray. So author installed a fuel accumulator and an electromagnetic controller in order to keep the constant fuel injection rate with the time variation. With this modified fuel injection system, spray tip penetration, spray angle and initial spray development process are investigated by instantaneous photographic method. The results obtained in this study are as follows : 1) The initial shape of injection of diesel fuel spray shows the form of non-disintegrated intact core, but the formation of ligaments increasingly grows as the time increases. It can also be shown that fine droplets become disintegrated out from the ligaments. 2) The slope of spray tip penetration was changed to two different tendencies with time. The transition point of the slope is shown at the time of around between 0.09 msec and 0.4 msec from the beginning of injection. This is transition time from non-disintegrated intact core to formation of ligaments.

• The Korean Journal of Pain
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• v.23 no.1
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• pp.18-23
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• 2010

Background: Complications following lumbar transforaminal epidural injection are frequently related to inadvertent vascular injection of corticosteroids. Several methods have been proposed to reduce the risk of vascular injection. The generally accepted technique during epidural steroid injection is intermittent fluoroscopy. In fact, this technique may miss vascular uptake due to rapid washout. Because of the fleeting appearance of vascular contrast patterns, live fluoroscopy is recommended during contrast injection. However, when vascular contrast patterns are overlapped by expected epidural patterns, it is hard to distinguish them even on live fluoroscopy. Methods: During 87 lumbar transforaminal epidural injections, dynamic contrast flows were observed under live fluoroscopy with using digital subtraction enhancement. Two dynamic fluoroscopy fluoroscopic images were saved from each injection. These injections were performed by five physicians with experience independently. Accuracy of live fluoroscopy was determined by comparing the interpretation of the digital subtraction fluoroscopic images. Results: Using digital subtraction guidance with contrast confirmation, the twenty cases of intravascular injection were found (the rate of incidence was 23%). There was no significant difference in incidence of intravascular injections based either on gender or diagnosis. Only five cases of intravascular injections were predicted with either flash or aspiration of blood (sensitivity = 25%). Under live fluoroscopic guidance with contrast confirmation to predict intravascular injection, twelve cases were predicted (sensitivity = 60%). Conclusions: This finding demonstrate that digital subtraction fluoroscopic imaging is superior to blood aspiration or live fluoroscopy in detecting intravascular injections with lumbar transforaminal epidural injection.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.20-27
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• 2000

Characteristics of two favorite injection tools for gasoline direct injection application were compared. An air-assisted fuel injector (AAFI) and a high-pressure swirl injector (HPSI) were designed and fabricated for prototype development, and the characterization strategies and processes for both injection tool have been arranged in parallel. Characterization works were carried out mainly through measurements, and in some cases, computational fluid dynamic analysis was utilized. In this paper, overall characteristics defined as flow rate, spray pattern, penetration, internal spray structure and drop size distribution, was discussed. The AAFI was found to be advantageous in flexibility of fuel flow rate, and the HPSI in stability and precision. Spray shape factor was introduced to describe the development of intermittent sprays from both injectors. Axial penetration appeared to be almost linear in the case of the AAFI while its speed continuously decreased with time in the HPSI.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2006.05a
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• pp.133-133
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• 2006

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.272-279
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• 2012

In order to effectively treat livestock wastewater in constructed wetlands by natural purification method, removal velocities of pollutants under different injection methods in constructed wetlands were investigated. The removal velocities of chemical oxygen demand (COD), suspended solid (SS), T-N and T-P by continuous injection method were slightly rapid than those by intermittent injection method in full-scale livestock wastewater treatment plant. The removal velocity (K; $day^{-1}$) of COD by continuous injection method was $0.38\;d^{-1}$ for $1^{st}$ bed, $0.13\;d^{-1}$ for $2^{nd}$ bed, $0.17\;d^{-1}$ for $3^{rd}$ bed, $0.05\;d^{-1}$ for $4^{th}$ bed and $0.17\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of COD in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.210\;d^{-1}$, $0.086\;d^{-1}$, $0.222\;d^{-1}$, $0.053\;d^{-1}$ and $0.137\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of SS by continuous injection method was $0.750\;d^{-1}$ for $1^{st}$ bed, $0.108\;d^{-1}$ for $2^{nd}$ bed, $0.120\;d^{-1}$ for $3^{rd}$ bed, $0.086\;d^{-1}$ for $4^{th}$ bed and $0.292\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of SS in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.485\;d^{-1}$, $0.056\;d^{-1}$, $0.174\;d^{-1}$, $0.081\;d^{-1}$ and $0.227\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of T-N by continuous injection method was $0.361\;d^{-1}$ for $1^{st}$ bed, $0.121\;d^{-1}$ for $2^{nd}$ bed, $109\;d^{-1}$ for $3^{rd}$ bed, $0.047\;d^{-1}$ for $4^{th}$ bed and $0.155\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of T-N in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.235\;d^{-1}$, $0.071\;d^{-1}$, $0.171\;d^{-1}$, $0.058\;d^{-1}$ and $0.126\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of T-P by continuous injection method was $0.803\;d^{-1}$ for $1^{st}$ bed, $0.084\;d^{-1}$ for $2^{nd}$ bed, $0.076\;d^{-1}$ for $3^{rd}$ bed, $0.118\;d^{-1}$ for $4^{th}$ bed and $0.301\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of T-P in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.572\;d^{-1}$, $0.049\;d^{-1}$, $0.090\;d^{-1}$, $0.112\;d^{-1}$ and $0.222\;d^{-1}$, respectively.

• Korean Journal of Veterinary Research
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• v.45 no.1
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• pp.131-137
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• 2005

To assess anesthetic depth using quantitative electroencephalography (q-EEG), we recorded processed EEG (raw EEG) till 100 minutes in beagle dogs anesthetized for 60 minutes with tiletamine/zolazepam (n=5, TZ group), xylazine/ketamine (n=5, XK group) and propofol (n=5, PI group) by intermittent bolus injection. Raw EEG was converted into 95% spectral edge frequency (SEF) and median frequency (MF) through fast fourier transformation (FFT) method. 95% SEF value of TZ group was significantly higher (p<0.05) than the XK group from 10 minutes to 100 minutes. 95% SEF value of PI group was significantly higher (p<0.05) than the XK group from 10 minutes to 40 minutes, and significantly low (p<0.05) than XK group at 90 and 100 minutes. MF was significantly higher (p<0.05) in TZ group from 60 minutes to 100 minutes. Based on these results, using dissociative agent with ${\alpha}_2$-adrenergic agent is more potent in CNS depressed than using dissociative agent alone, and low doses of propofol has a disinhibitory effect on CNS.

• Journal of ILASS-Korea
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• v.9 no.1
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• pp.37-42
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• 2004

In a port fuel injection system of engine, a large part of fuel injected into an intake port adheres on its wall and inlet valve. Consequently, the wall impinging spray interaction might occur the generation of several harmful phenomena. There are uncontrollable mixture formation, an accidental backfire and unburned hydrocarbons. Therefore, it is important to analyze the fuel behavior during the spray-wall interaction. In this study, splash characteristics of impingement and reflecting or scattering behavior of droplets of fuel injected from EFI nozzle were studied experimentally. A test fuel used is LAWS and its physical characteristics are similar to the conventional gasoline except for the ignition point. Since the liquid film formed immediately after impinging on an impingement plate is unstable, it is easy to cause secondary disintegration. In addition, when the intermittently impingement on the impingement plate with LAWS, the splash ratio is around 0.6. If an injection period becomes longer, liquid film will become thick and the splash ratio will fall bout 10 percent. On the other hand, when the injection period of an intermittent spray is long, the same time lapse as a continuous spray is shown.