• Journal of Environmental Science International
• /
• v.15 no.6
• /
• pp.527-532
• /
• 2006

The purpose of this study is to clarify the characteristic of urban heat island intensity in urban area formed at a basin. Thermal environments for basin-type cities are influenced by significant topographic relief winds. In this study, we analyzed the diurnal variations of the heat island intensity according to meteorological condition and season using AWS(Automatic Weather observation System) data in Daegu Metropolitan area for 1 year(3/April, 2003 $\sim$ 2/April, 2004). In this study, we defined the urban heat island intensity as the air temperature difference between two points, the downtown and the suburban area. The suburban area is located at valley mouth around the western tip of Daegu. The results are summarized as follows; 1. The maximum heat island intensity was recorded at early morning under the meteorological conditions, calm and clear 2. The heat island intensity was strong in the order of winter, fall, spring and summer. 3. The heat island intensity came out minus values in the afternoon. This phenomenon is known as a com mon for basin-type cities. 4. The heat island intensity was twice or more in clear and calm than not so.

• The Korean Journal of Pain
• /
• v.9 no.1
• /
• pp.183-186
• /
• 1996

When medical therapy fail to relieve pain at tolerable level for patients confirmed with trigeminal neuralgia, presence of mass lesion excluded, surgery is indicated. Innumerable surgical strategies have been attempted for the treatment of trigeminal neuralgia but only four have proven appropriate: (1)stereotactic radiofrequency gasserian ganglionotomy, (2) percutaneous glycerol gangliolysis, (3) percutaneous microcompression, (4) microvascular decompression. Radiofrequency thermocoagulation of the gasserian ganglion stems from the efforts of Sweet. This technique is the surgical treatment of choice around the world for surgical treatment for trigeminal neuralgia. Since 1986, over 14,000 cases have been reported utilizing this technique. To improve the treatment method further, an electrode with a flexible curved tip has been developed for easier and more precise electrode placement and lesion production during the thermocoagulation of gasserian ganglion. This operation was performed recently on three patients at Hallym University Hospital. using a curved tip electrode. Complete relief of pain was achieved for all patient. However, some complications were noted.

• Journal of Yeungnam Medical Science
• /
• v.13 no.1
• /
• pp.152-157
• /
• 1996

We report a case of subungual solitary glomus tumor in a 28-year-old female, who has suffered from pain and tenderness of the left 4th finger tip for about 5 years. Simple surgical excision was performed for removal of the tumor mass and for the relief of the subjective symptoms. No recurrence has been observed for 5 months following excision of the tumor.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.30 no.10 s.253
• /
• pp.1019-1025
• /
• 2006

Numerical simulations were conducted on the gerotor type oil pump. Three oil pump models having different port and groove shape were considered. Firstly, two original models (baseline & variant.1 model) were simulated in order to validate the accuracy of the simulation results and to better understand the flow characteristics in the pump. It was found that the cavitation phenomenon as well as the teeth tip leakage is most important parameter on the pump performance. Based on the simulation results of the original models, final model (variant.2 model) which has improved port shape and pressure relief valve is suggested to enhance pump performance and to reduce driving torque. The volumetric efficiency and the hydraulic torque of the Variant.2 model is improved 4% and reduced 6.1% each at 2000RPM in experiment.

• Journal of Drive and Control
• /
• v.17 no.1
• /
• pp.1-12
• /
• 2020

This study was to develop a simulation model of a compound planetary gear reducer for the final driving shaft using a gear analysis software (KISSsoft, Version 2017, KISSsoft AG, Switzerland). The aim of this study is to analyze transmission error and the tooth load distribution through micro-geometry using the simulation model. The tip and root relief were modified with Micro-geometry in the profile direction, and crowning was modified with Micro-geometry in the lead direction. The transmission error was analyzed using the PPTE (Peak to Peak Transmission Error) value, and the tooth load distribution was analyzed for the concentrated stress on the tooth surface. As a result of modifying tip and relief in the profile direction, the transmission error was reduced up to 40.7%. In the case of modifying crowning in the lead direction, the tooth load was more evenly distributed than before and decreased the stress on the tooth surface. After modifying the profile direction for the 1st and 2nd planetary gear train, the bending and contact safety factors were increased by 31.7% and 17%, and 18.3% and 12.5% respectively. Moreover, the bending and safety factors after modifying lead direction were increased by 59.5% and 32.7%, respectively for the 1st planetary gear train, and 59.6% and 43.6%, respectively for the 2nd planetary gear train. In future studies, the optimal design of a compound planetary gear reducer for the final driving shaft is needed considering both the transmission error and tooth load distribution.

• The Korean Journal of Pain
• /
• v.13 no.1
• /
• pp.74-78
• /
• 2000

Background: Epidural Adhesiolysis is an interventional pain management technique for patients with low back pain. In addition to local anesthetics and corticosteroid, hypertonic saline (NaCl) are used for the technique. Present study was aimed to compare analgesic and adverse effects of two different concentration of hypertonic saline in Epidural Adhesiolysis. Methods: Fifty-three subjects with low back pain with radiculopathy were assigned to one of two epidural adhesiolysis treatment groups: 8% (Group I, n=26) or 10% (Group II, n=27) hypertonic saline. 17 G epidural needle was inserted at sacral hiatus and catheter was advanced untill its tip was located at lesion site under fluoroscopic guidance. Subjects in all treatment groups received epidural corticosteroid and local anesthetic. And then, hypertonic saline injection via catheter were carried out daily for 3 days. Evaluation included assessment of pain relief (Numerical Rating Scale; NRS) at post-epidural adhesiolysis 1, 2, 3 days, 1 week, and 1, 3 months. We also looked for complications of epidural adhesiolysis at different concentration of hypertonic saline. Results: Statistical analysis demonstrated that NRS was not significantly different between two groups during 3 months after epidural adhesiolysis. There were no major differences of complications between two groups and disappeard after a few months without residual sequelae. Conclusions: We conclude that epidural adhesiolysis using 8% hypertonic saline is effective for relief of low back pain with proven lumbosacral fibrosis without any residual sequelae compared with 10%.

• The Korean Journal of Pain
• /
• v.14 no.2
• /
• pp.234-238
• /
• 2001

Percutaneous laser discectomy has potential advantages over conservative therapy and classical open surgery as a minimally invasive procedure, although clinical experiences are limited. We experienced a patient treated with herniated lumbar discs using Nd：YAG laser. A 55-year-old woman complained of severe back pain with sciatica on L4/5 and L5/S1 dermatome for several months. The MRI finding showed bulging discs at L4/5 and L5/S1. Epidural, transsacral and root block treatments were attempted without effect. Under fluoroscopic guidance, a 14 G biopsy needle was inserted into the L4/5 and L5/S1 disc spaces to the margin of the nucleus pulposus. Laser irradiation for vaporization of tissue was performed at 20 W/second to 1200 J. A laser fiber ($600{\mu}m$) was advanced 1 cm from the tip of the needle. At the end of the procedure, the patient began to feel relief of pain (VAS changed from 9 to 4) and was discharged the same day after staying 2 hours in the recovery room. Antibiotics were administered for prevention of discitis. She had no complaints of pain until the 1-month follow up visit. Percutaneous laser discetomy technique has the disadvantages of expensive equipment, high temperature and amount of vaporing disc tissue is empirical. However, this technique, as one of the therapeutic modalities for disc herniation, provides faster relief from acute attack than conservative management techniques in carefully selected patients with sciatica due to disc prolapse.

• The Korean Journal of Pain
• /
• v.20 no.2
• /
• pp.116-122
• /
• 2007

Background: Lumbar zygapophysial joints are a common source of chronic lower back pain and radiofrequency thermocoagulation (RF) of the medial branches (MB) has been shown to be effective at providing substantial pain relief for chronic low back pain. Therefore, we carried out this study to determine the short term outcomes and prognostic factors of RF on the MB of patients with lumbar facet syndrome. Methods: We performed RF in fourteen patients who showed greater than 80% pain relief up to three times after a diagnostic MB block was conducted using 0.3 ml of 0.5% bupivacaine. Using 10 cm curved electrodes with 10-mm active tip, a 60 second, $80^{\circ}C$ lesion was made after electrical stimulation at 50 Hz for sensory and 2 Hz for motor nerve testing. The degree of pain relief was then assessed after 2 weeks, and again after 3 months using a visual analog scale (VAS) and a four point Likert scale. The outcome was regarded as 'success' if at least a 50% reduction in the VAS was observed. Possible prognostic factors between the two groups were also evaluated Results: The success rate was 71.4% (10/14) after three months of follow-up. However, there were transient complications, such as neuritis like syndrome, in 4 patients. In addition, short symptom duration and low minimal voltage (< 0.4 V) for sensory stimulation were shown to be the relevant prognostic factors for a successful outcome. Conclusions: RF may be an alternative to repeated MB block or intraarticular injection for palliation of lumbar facet syndrome. For better outcomes, early diagnosis and strict patient selection should be coupled with efforts to avoid anatomically incorrect RF.

• The Korean Journal of Pain
• /
• v.2 no.1
• /
• pp.36-41
• /
• 1989

Splanchnic nerve block is performed to relieve intractable upper abdominal pain caused by carcinoma of the pancreas, stomach, liver, or colon; and upper abdominal metastasis of tumors having more distant origins. We have performed splanchnic nerve blocks under control of X-ray fluoroscopy, for all cases of alcohol splanchnic nerve block at $L_1$ vertebra, to determine both the position of the needle tips and the spread of contrast media. During the period from December 1987 to August 1988, this method was used in 40 cases of malignancy at Severance Hospital and we clinically evaluated the location of the needle tip and the spread of contrast media. The results were as follows: 1) Our method was a retrocrural approach, the splanchnic nerve block, in all cases. 2) Most of the inserted needle points were located in the upper and anterolateral part of the $L_1$ vertebra on the antero posterior roentagenogram and in the upper quarter anteriorly on the lateral roentgenogram. 3) There was no specific relationship between the location of the needle and the spread of the contrast media. 4) The contrast media was spread around the needle and then upward along the anterior margin of the vertebral body in most of the cases. 5) Pain relief was obtained immediately in 37 cases (92.5%), but in 3 cases only after a second splanchnic nerve block.

• The Korean Journal of Pain
• /
• v.4 no.2
• /
• pp.127-132
• /
• 1991

Recently a non-electronic, disposable and portable infusor(Baxter infusor with patient control module, Baxter health care Co., Deerfield IL 60015 USA: BI $\bar{c}$ PCM) has been developed that will deliver both a continuous drug infusion as well as allow the patient to deliver extra doses of medication on a demand basis under predetermined limitation of analgesics. Patients may also not require as high analgesic dose rate to control pain when the acceptable and tolerable level of pain relief can be maintained by this device. From April l99l, we have used a total l93 units of BI $\bar{c}$ PCM. These units consisting of two components which one made by a balloon reservoir(capacity 65 ml, flow rate 0.5 ml/hr) to store medication and to regulate the pump power(490 torr), and another two PCMs to regulate additional analgesic administration by patients demand at intervals of 1S minutes and 60 minutes. The dose administered to the patient can be varied by changing the concentration of the infusate within the balloon reservoir. These devices were utilized for the pain control of 44 patients. These patients were divided into two groups. Twenty seven cases had cancer pain and 17 cases had non-cancer pain. The Touhy needle(No. l8 G.) tip was inserted into the epidural space and was used to guide the catheter to the spinal nerve level corresponding to the most painful area. The device was connected to the opposite site of the catheter tip and was filled with 60 ml of mixture solution such as 0.5% bupivacaine 15 ml, morphine HCl 10 mg, trazodone 10 ml, Tridol 3 ml and normal saline 31 ml were administed as the initial dose. When the initial dose was less effective, the next dose could be varied by increasing the concentration of bupivacaine, by adding more morphine (5~10 mg), and by reducing the volume of normal saline. Using these modules of drug self administration, we experienced the following: 1) Improvement of patient's self titration of analgesic requirement was provided. 2) The patients anxiety with pain recurrence resulting from delays in administering pain control medication was decreased significantly. 3) The working load accompanying with the single bolus injection as the usual method was reduced remarkably. 4) There was urinary retention in 5 cases and pruritus in 4 eases which developed as side effects but respiratory depression and vomiting was not encountered in a single case.