• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.4
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• pp.40-47
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• 2010

This study deals with the investigation about the effect of the pilot and split injection strategies on the spray-atomization characteristics of biodiesel fuel derived from a soybean oil. Experimental results were compared with the calculation results obtained from the numerical analysis. Fuel properties of biodiesel according to the variation of the fuel temperature were inserted to the fuel library in the KIVA code. The amount of fuel injection is divided into equal mass for each split and main injection. In this work, the pilot injection strategy can be achieved by the amount of fuel injection shortly before the start of the main injection. A spray tip penetration, radial distance and spray area were measured for the analysis of macroscopic spray characteristics. In addition, the local and overall droplet size distribution were calculated by using KIVA-3V code to study the effect of split and pilot injection on the atomization performance under high ambient pressure. From these studies, the experimental results showed the multiple injection induced the decrease of the spray tip penetration due to the reduction and division of the spray momentum compared to single injection. In the atomization performance, the droplet size increased in the case of the multiple injection a little. Moreover, the SMD slightly increased as the fuel droplets goes through the axial direction. The spray behavior of numerical results were well predicted the experimental multiple spray characteristics of biodiesel fuel.

• The Korean Journal of Pain
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• v.18 no.2
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• pp.176-180
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• 2005

Background: Epidural steroid injections benefit certain patients with radicular pain, and often have only a limited duration. We compared the efficacy of hyaluronidase and triamcinolone and triamcinolone alone in patients with lumbar herniated disc disease treated with transforaminal epidural block. Methods: Forty patients who had undergone a transforaminal epidural injection were retrospectively reviewed. The T group received triamcinolone and local anesthetics; whereas, the HT group received hyaluronidase, triamcinolone and local anesthetics. We evaluated the improvement as being good, moderate, mild or no improvement, and in those where the improvement was good or moderate, also evaluated the duration of pain relief. Data were collected from the medical records of patients or via phone calls, which were analyzed using Student t- and chi-squared tests. A value of P < 0.05 was considered significant. Results: There were no significant differences in the degree of pain improvement or duration of pain relief between the two groups. Conclusions: A hyaluronidase and triamcinolone injection during transforaminal epidural block has on benefit with respect to the degree of pain improvement or its duration compared to a triamcinolone only injection.

• The KSFM Journal of Fluid Machinery
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• v.10 no.3 s.42
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• pp.25-32
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• 2007

The present paper deals with the heat/mass transfer characteristics for the rotating impingement/effusion cooling system. By changing the size and number of injection hole, its effects on heat/mass transfer are investigated and three different injection hole cases are considered such as LH, DH and SH, respectively. Reynolds number based on the effusion hole diameter is fixed to 3,330 and two jet orientations are considered. A naphthalene sublimation method is used to obtain the heat/mass transfer coefficients on the effusion plate. The LH case shows that the local heat/mass transfer is significantly varied by the rotation. Moreover, the low and non-uniform Sh distributions occur because the impinging jet is deflected by Coriolis force. Meanwhile, for DH and SH cases, the local heat/mass transfer coefficients are enhanced significantly compared to LH case and the rotation effect decreases with increasing the jet velocity. The averaged Sh value of DH and SH case rises up to 45%, 85% than that of LH case. However, the uniformity of heat/mass transfer deteriorates due to the steep variation of heat/mass transfer.

• Archives of Craniofacial Surgery
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• v.12 no.2
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• pp.129-131
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• 2011

Purpose: The purpose of this report is to present a case of persistent parotid fistula treated successfully with preoperative botulinum toxin type A injection into the parotid parenchyma, followed by fistulectomy. Methods: A 72-year-old female patient presented to the hospital with a 5-month history of clear, watery discharge from a tiny opening on the left cheek, which increased during food intake. A chemistry test of the fluid revealed an high amylase level. An ultrasonography of left parotid gland showed a $1.13{\times}0.6cm$ sized fistula. After demarcating the left parotid gland with assistance of ultrasonography, a total 40 units of botulinum toxin type A (Botox, Allergan, Irvine, CA) was injected into 4 subdivisions of the left parotid gland. The clear serous discharge ceased completely on the 5th day after botulinum toxin injection. On the 7th day, a fistulectomy was performed under the local anesthesia. Results: The parotid fistula healed completely without complications. During the 6-month follow up period, there was no discharge from the cheek. Conclusion: On the basis of our experience with type A botulinum toxin as a local anticholinergic agent in treating parotid fistula, preoperative botulinum toxin A injection seems to be very useful to prevent recurrence after fistulectomy.

• The Korean Journal of Pain
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• v.26 no.4
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• pp.387-391
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• 2013

A 64-year-old woman visited our pain clinic with the pain of right lateral side of thigh for one year. Her pain always started from knee and was radiated to buttock area when symptom was severe. She showed significant tenderness at knee lateral side and local tightness at lateral thigh. Magnetic resonance image of the knee was performed and we could identify high signal intensity of iliotibial band through coronal and axial view. In spite of medication and physical stretching exercise of iliotibial band for one month, she did not show any improvement of pain. To alleviate her symptom, ultrasound guided local corticosteroid injection targeting beneath the iliotibial band was performed. After the procedure, the reduction of pain was significant and there was no need for further management.

• 대한핵의학회:학술대회논문집
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• 1999.05a
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• pp.200-204
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• 1999

Rheumatoid arthritis (RA) is o chronic inflammatory disease of joints with proliferation of synovial epithelial tissue. Therapeutic approach of the RA consists of pharmacological and surgical interventions. Synovectomy is indicated in patients with progressive inflammatory signs and symptoms intractable to medical treatment including local intracavitary steroid injection. Recently, local injection of radionuclides which emit high energy beta rays are labeled with chemical compounds such as $^{90}Y,\;^{165}Dy-ferric$ hydroxide macroaggregate and have been introduced as an alternative therapeutic modality to surgical synovectomy. Holmium-166 is one of beta emitter and Ho-166-chitosan complex was developed for radiation synovectomy. Preclinical trial is on-going at our hospital using Ho-166-chitosan. The procedure and methods of preclinical trial are discussed.

• Nuclear Engineering and Technology
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• v.38 no.8
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• pp.763-778
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• 2006

Injection of microbubbles within the turbulent boundary layer has been investigated for several years as a method to achieve drag reduction. However, the physical mechanism of this phenomenon is not yet fully understood. Experiments in a channel flow for single phase (water) and two phase (water and microbubbles) flows with various void fraction values are studied for a Reynolds number of 5128 based on the half height of the channel and bulk velocity. The state-of-the art Particle Tracking Velocimetry (PTV) measurement technique is used to measure the instantaneous full-field velocity components. Comparisons between turbulent statistical quantities with various values of local void fraction are presented to elucidate the influence of the microbubbles presence within the boundary layer. A decrease in the Reynolds stress distribution and turbulence production is obtained with the increase of microbubble concentration. The results obtained indicate a decorrelation of the streamwise and normal fluctuating velocities when microbubbles are injected within the boundary layer.

• YAKHAK HOEJI
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• v.47 no.2
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• pp.78-84
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• 2003

Local anesthetics are used to reduce pain, but they are so frequently injected to patients. So, we prepared lidocaine solid lipid microspheres (SLM) as long acting abdominal injection using spray drying method and evaluated drug entrapment, particle size, SEM, zeta potential and in vitro and in vivo drug release pattern, The particle sizes of SLM were 30∼100$\mu$m and it is enough to inject into abdominal tissue. The entrapment efficiency of SLM was over 95％ as spray drying method. Surfactant and PC decreased the burst effect by 20∼30％. In in vivo test, C-6 showed controlled release concentration profile in plasma for 8 days and C-5 sustained longer than we expected.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.596-596
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• 2003

The purpose of this study were to evaluate the effect of epinephrine-containing local anesthetics on pulpal blood flow (PBF) and to compare the change of pulpal blood flow after cavity preparation between in non-anesthetized teeth and in anesthetized ones in cats. Nine cats were initially anesthetized with intra-muscular injection of keramine(75mg/kg) and acepromazine(2.5mg/kg). Periapical radiographs of canine teeth were taken, followed by intra-venous injection of alpha-chloralose(40mg/kg) and urethane (500mg/kg) through the femoral vein for the general anesthesia.(중략)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.410.1-410.1
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• 2002

Local anesthetics are used to reduce pain. but they are so frequently injected to patients. So we prepared lidocaine solid lipid nanopaticles for long acting subcutaneous injection to decrease the number of times of injection. Solid lipid nanoparticles were prepared by spray drying method. First. drug. lipid. plasticizer and surfactant were dissolved in methylene chloride. and we operated spray dryer using this solution at setting value. (omitted)