• Journal of ILASS-Korea
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• v.4 no.2
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• pp.19-32
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• 1999

The present study investigated the forms and behaviors of fuel during intake and compression process, and the initial flame stability in a lean burn engine modified as a single cylinder engine equipped with quartz windows for visualization. PLIF(Planar Laser Induced Fluorescence) method with KrF Excimer laser was used for measuring the fuel distributions. The principal design concept of the lean burn nin in this study is the axial stratification in the fuel distribution via fuel injection during intake process and different shapes of intake ports; helical and straight. The experiments showed that fuel flowed in as a vapor state in the early part of intake process and lots of this mixture mated down along the intake valve side cylinder wall, but in the latter part, a lot of fuel flowed in as a liquid state and this fuel stayed in the upper part of cylinder, after that the dense fuel cloud moved upward in the early of part compression process. It became clear that the fuel flowed in via straight port had a important role in the axial fuel stratification.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.3
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• pp.221-228
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• 2013

An experimental study was carried out to investigate the effects of the injection timing on the spray and combustion characteristics in a spray-guided direct-injection spark-ignition (DISI) engine under lean stratified operation. An in-cylinder pressure analysis, exhaust emissions measurement, and visualization of the spray and combustion were employed in this study. The combustion in a stratified DISI engine was found to have both lean premixed and diffusion controlled flame combustion characteristics. The injection timing condition corresponding to the stratified mixture characteristics was verified to be a dominant factor for these flame characteristics. For the early injection timing, a non-luminous blue flame and low combustion efficiency were observed as a result of the lean homogeneous mixture formation. On the other hand, a luminous sooting flame was shown at the late injection timing because of an under-mixed mixture formation. In addition, the smoke emission and incomplete combustion products were increased at the late injection timing as a result of the increased locally rich area. On the other hand, the NOx emissions decreased and IMEP increased as the injection timing retarded. The combustion phasing produced by the injection timing was verified as the reason for this observation.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.9
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• pp.56-62
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• 1999

The disintegration of transient diesel spray in early was investigated at different opening pressure and chamber pressure by measns of shadowgraph method using nanolite and still camera. Diesel spary was injected into the spray chamber which was charged with high pressure nitrogen gas. Atthe begining of injection, a liquid column that was almost the same diameter as the nozzle hole was observed . Spray tip penetration and spray angle were always increased with an increase in opening pressure.

• Journal of Korean Foot and Ankle Society
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• v.21 no.4
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• pp.117-121
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• 2017

The incidence of arthritis in the ankle is relatively low compared to other joints. On the other hand, it receives a lot of pressure per unit area, is vulnerable to damage, and arthritis can arise after trauma. Early ankle arthritis can be considered a case of osteophyte subchondral sclerosis without narrowing of the joint space. Conservative treatment, such as weight control, insole use, drug use, and injection therapy for early ankle arthritis, is effective and can be considered before surgical treatment. Nevertheless, if pain is persistent, surgical treatment to remove bony spurs is effective. Ensuring that there is no other cause of pain when deciding whether to perform an operation is very important.

• Journal of radiological science and technology
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• v.15 no.1
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• pp.123-130
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• 1992

This study was prepared to observe the change of enzyme activities in kidney treated with red ginseng extract in the gamma ray irradiated mice. Determine the activity of SOD, peroxidase, catalase in the kidney a period of 1 day, 2 day, 3 day, 4 day, 5 day after a saline injection or injection of red ginseng extract or gamma ray irradiatied group into four classify. The activity SOD and catalase showed a tendency to increase and recovery at the early state but pay no regard. Wherease, the activity of peroxide restored and increased pay regard. A physiological saline injection group after gamma ray irradiation showed a tendency to diminish after remakable increase of activity of SOD, peroxidase and catalase than control group. Injection group of red ginseng extract after gamma ray irradiation observed rapid recovery on activity of SOD, peroxidase, catalase than a saline injection group. Experimental result suggested that injection of red ginseng extract after irradiation have the recovery effect on the changed of activity of SOD, peroxidase and catalase against radiation injury.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.193-197
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• 1998

Frozen shoulder is known as a self-limited disease. But, its long duration and pain nature can make the patients debilitative. And most patients cannot tolerate a chronically painful extremity and are concerned about the possibility of developing permanent dysfunction. In painful phase of frozen shoulder, some aggressive mordalties as like trigger point injection or suprascapular nerve block can beneficial to: reduce discomfort and pain. In order to document clinical results, we evaluated the results of 134 frozen shoulders treated with trigger point injection and/or suprascapular nerve block at Kyungpook National University Hospital, from January 1995 to April 1997. The treatment group was divided into 3 modalities: 17 cases in trigger point injection(TPI), 39 cases in suprascapular nerve block(SSB), and 78 cases in both methods. The supportive treatment including oral medication, heat and stretching exercise was also applied. The average age at the time of diagnosis was 57 years old and average follow-up time was 18 months. The results were as follows: Average time of significant improvement in pain was 9 days. Eighty-eight percent (119 cases) was improved in pain and range of motion after injecllion treatments; 82%(14/17) with TPI, 85%(33/39) with SSB, and 92%(72/78) with both. Early improvement of paih within 1 week was 72% in the treatment-responsive group, in which TPI group has 100% response(14/14) and sse has 94% response(31/33)

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.16 no.2
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• pp.129-134
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• 2005

Background and Objectives : Artecoll(R) is an injectable soft tissue filler, which is a suspension of polymethylmethacrylate microspheres in $3.5\%$ bovine collagen solution. The authors aimed to determine the clinical of Artecoll of Artecoll(R) as an injection material into the vocal fold to correct the glottal insufficiency caused by unilateral vocal cord paralysis. Materials and Methods : Forty-one consecutive patients with unilateral vocal cord paralysis received percutaneous Artecoll injections under local anesthesia. Acoustic, aerodynamic and stroboscopic analyses were prospectively provided before, 1 week and 3 months after injection. Perceptual GRBAS grading by speech language pathologists and subjective ratings of the hoarseness and aspiration by the patients were also obtained. Results : Aerodynamic parameter(maximal phonation time) were significantly improved after the injection (p<0.05). Acoustic parameters (jitter and shimmer) were improved at the 3rd month follow-up. GRBAS uading and patients own subjective scaling of hoarseness and aspiration also showed significant improvement (p<0.05). Early or delayed significant side effects were not observed. Conclusion : Vocal fold injection with Artecoll is a convenient, safe and useful method of temporarily correcting the glottal insufficiency. Further long-term follow-up studies will answer the usefulness and safety of the Artecoll injection laryngoplasty.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.3
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• pp.146-153
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• 2011

American NREL (National Renewable Energy Laboratory) reported that BDF20 could reduce PM, CO, SOx, and cancerogenic matters by 13.6%, 9.3%, 17.6%, and 13% respectively, compared to diesel fuel. BDF20 has been being tested on garbage trucks and official vehicles at Seoul City, which is positive on air environment, but negative on combustion by higher viscosity in winter season. This study investigated the combustion characteristics by applying pilot injection for improving the deterioration of combustibility caused by the higher viscosity of the BDF20 with the combustion flames taken by a high-speed camera and the cylinder pressure diagram. A 4-cycle single-cylinder diesel engine was remodeled to a visible 2-cycle engine taking the flame photographs, which has a common-rail injection system. The test was done laboratory temperature at $5{\sim}6^{\circ}C$. The results obtained are summarized as follows, (1) In the case of without pilot injection, the flame propagation speed was slowed and the maximum combustion pressure became lower. The phenomena became further aggravated as the fuel viscosity gets higher. (2) In the case of with pilot injection, early stage of combustion such as rapid ignition timing and flame propagation was activated since intermediate products formed by pilot injection act as a catalyst for combustion of main fuel.

• Tunnel and Underground Space
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• v.26 no.3
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• pp.166-180
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• 2016

The present study numerically simulated the CO2 injection into the saline aquifer of CO2CRC Otway pilot project and the resulting hydrological-mechanical coupled process in the storage site by TOUGH-FLAC simulator. A three-dimensional numerical model was generated using the stochastic geological model which was established based on well log and core data. It was estimated that the CO2 injection of 30,000t over a period of 200 days increased the pressure near the injection point by 0.5 MPa at the most. The pressure increased rapidly and tended to approach a certain value at an early stage of the injection. The hydrological and mechanical behavior observed from the CO2 flow, effective stress change and stress-strength ratio revealed that the CO2 injection into the saline aquifer under the given condition would not have significant effects on the mechanical safety of the storage site and the hydrological state around the adjacent fault.

• Journal of Embryo Transfer
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• v.5 no.2
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• pp.38-44
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• 1990

This study was carried out to produce superior dairy cattle by embryo transfer. Seven dairy cows were superovulated with divided injection of FSH 4Omg for 5 days started on day 9 to 14 of the estrus cycle and injection of PGF$_2$$\alpha$ 45mg on day 4 of FSH injection. Donor cows were flushed to collect embryos on day 7 or 8 of the estrus cycle. Fresh embryos collected were transferred to synchronized dairy recipients or frozen using glycerol 3 step method to he equilibrated. And 35 embryos which were frozen using glycerol 6 step method were imported from U.S.A. After glycerol dilution of frozen embryos was done by reverse density during freezing. frozen-thawed embryos were transferred to synchronized dairy or beef recipients. The results obtained were as follows; 1. Total of 24 embryos were collected from 7 donor cows flushed and transferable embryos were 18 (75.0%). 2. Among 24 embryos. morula, early blastocyst, blastocyst, expanded blastocyst and unfertilized ova were 3 (12.5%), 1 (4.2%), 10 (41.6%), 4 (16.7%) and 6 (25.0%), respectively. 3. Heat inducing rate after 1st and 2nd injections of PGF$_2$$\alpha$ in Holstein and beef cattle was 83.3% and 71.4% and 62.5% and 69.2%, respectively. 4. Among 56 recipients, 23 head were pregnant (41.1%). The pregnancy rate of fresh embryos was 50.0% (1/2 heads) and the pregnancy rate of frozen embryos which were frozen using glycerol 3 step and using glycerol 6 step imported from U.S.A. was 52.6%(l0/19 heads) and 34.3%(12/35 heads), respectively. 5. The pregnancy rate of blastocyst (60.0%) was higher than that of morula (39.0%), early blastocyst (25.0%) and expanded blastocyst (0%). 6. The pregnancy rate of grade I embryos (52.2%) was higher than that of grade 2 (34.6%) and grade 3 (28.6%). 7. The pregnancy rate according to synchrony of recipient with donor was higher in simultaneous recipient (55.0%) and +l2hrs' (53.8%) than -24hrs' (23.5%), -l2hrs' (20.0%) and +24hrs' (0%).