• The Journal of the Korean bone and joint tumor society
• /
• v.4 no.1
• /
• pp.37-43
• /
• 1998

Between 1992 and 1996, 5 patients with the giant-cell tumor of the spine were treated. Four were female and one was male. The mean age was 34 years old, and the mean follow-up time was 36 months. The locations of the lesions were the cervical spine in 1, the thoracic spine in 3, and the lumbar spine in 1. Pain was the predominant presenting symptom in all cases and four had a neurological deficit. A combined anterior and posterior surgical approach wds as performed in all cases, which were also treated with AIF(anterior interbody fusion) and anterior and/or posterior instrumentation. Adjuvant radiation therapy was performed in 1 case of cervical spine. At the final follow-up, the pain and neurologic symptoms were improved. Radiologic examination showed no evidence of local recurrence and no failure of instrumentation of the spine.

• Journal of Korean Neurosurgical Society
• /
• v.39 no.3
• /
• pp.192-197
• /
• 2006

Objective : Eleven patients treated with posterior cerebral artery[PCA] aneurysm during 6.3-years period are retrospectively reviewed to determine treatment outcome. Methods : Eleven patients with PCA aneurysm were treated from January 1998 to May 2004. Their medical records and radiologic studies were reviewed retrospectively. The records of these patients were analysed with particular reference to their demographic details, mode of presentation, and treatment outcome. Results : Of the 11 patients, 8 patients presented with symptoms related aneurysmal bleeding. Three patients had unruptured PCA aneurysms. Open or endovascular surgery was performed in 9 patients; None of these patients exhibited a third nerve palsy, visual field deficit, or hemiparesis at the time of presentation. Postoperatively, 2 made a good recovery, 2 had a moderate disability because of cerebral infarction after surgery, and 5 had a severe disability because of cerebral infarction after surgery. Of 2 conservatively treated patients, 1 was doing well but the other died as a result of brain swelling. Conclusion : The treatment of the PCA aneurysms is difficult regardless of the aneurysmal size, site, and treatment modality. All reasonable treatment to reduce the risk of associated morbidity should be considered.

• Journal of Korean Neurosurgical Society
• /
• v.60 no.1
• /
• pp.82-88
• /
• 2017

Objective : We assessed the surgical results of bipolar release in 31 adult patients with uncorrected congenital muscular torticollis (CMT) and more than 12 months of follow-up. Methods : Thirty-one patients underwent a bipolar release of the sternocleidomastoid muscle (SCM) and were retrospectively analyzed. The mean follow-up period was 14.9 months (range, 12-30). The mean age at time of surgery was 30.3 years (range, 20-54). Patients were evaluated with a modified Lee's scoring system, cervicomandibular angle (CMA) measurement, and a global satisfaction rating scale using patient self-reporting. Results : The modified Lee's scoring system indicated excellent results in 4 (12.9%) patients, good in 18 (58.1%), and fair in 9 (29.0%) at the last follow-up after surgery. The improvements in neck movement and head tilt were statistically significant (p<0.05). The preoperative mean CMA was $15.4^{\circ}$ (range, 5.4-29.0), which was reduced to a mean of CMA of $6.3^{\circ}$ (range, 0-25) after surgery (p<0.05). The global satisfaction rating scale was 93.7% (range, 90-100). A transient sensory deficit on the ipsilateral lower ear lobe was noted in three cases. No significant permanent complications occurred. Conclusion : Bipolar release of the SCM is a safe and reliable technique for the treatment of CMT in adults.

• Journal of the Korean Arthroscopy Society
• /
• v.13 no.2
• /
• pp.119-125
• /
• 2009

The primary purposes of revision repair for a failed rotator cuff repair are a relief of pain and functional improvement. Therefore, revision repair is most proper in patients with the functional deficit accompanied with the shoulder weakness as well as the persistent pain. The important factor that is considered in revision repair is a quality of torn cuff. Especially, Care must be taken to ensure that the revision repair is possible, considering the size of tendon defect, atrophy of the muscle, fatty infiltration and extent of the retraction of tendon. Revision repair of a failed rotator cuff repair is more difficult, and the functional results are less satisfactory than those of primary repair, because excessive bursal scarring and tendon retraction may be exhibited, a large or massive tear is often detected, tear has usually been present for a long time, and a quality of muscle-tendon may be poor. So, we discuss our experiences related to revision repair after a failed cuff repair that has been recently introduced through the articles.

• Journal of the Korean Solar Energy Society
• /
• v.35 no.1
• /
• pp.35-43
• /
• 2015

A numerical simulation on the wake flow of a wind turbine which is a scaled version of a multi-megawatt wind turbine has been performed. Two different inlet conditions of averaged wind speed including one below and one above the rated wind speed were used in the simulation. Steady-state pitch angles of the blade associated with the two averaged wind speeds were imposed for the simulation. The steady state analysis based on the Reynolds averaged Navier-Stokes equations with the method of frame motion were used for the simulation to find the torque of the rotor and the wake field behind the wind turbine. The simulation results were compared with the results obtained from the wind tunnel testing. From comparisons, it was found that the simulation results on the turbine power are pretty close to the experimental values. Also, the wake results were relatively close to the experimental results but there existed some discrepancy in the shape of velocity deficit. The reason for the discrepancy is considered due to the steady state solution with the frame motion method used in the simulation. However, the method is considered useful for solutions with much reduced calculation time and reasonably good accuracy compared to the transient analysis.

• Physical Therapy Rehabilitation Science
• /
• v.10 no.4
• /
• pp.438-443
• /
• 2021

Objective: The purpose of this study was to determine the effect of the difference in mask filters on the respiration rate of healthy people. Design: A randomized cross-over design. Methods: A total of 15 subjects were selected for this study (n=15). After filling out the Physical Activity Readiness Questionnaire, the selected participants abstained from caffeinated beverages and meals 30 minutes before and sat in a chair 10 minutes before stabilizing their breathing. Afterwards, the lung function test was performed 3 times for each mask, and the maximum value was used. The provided masks were Mask Free, Dental Mask, KF80, and KF94. Exhalation was measured for 6 seconds for each mask, and breathing was stabilized by repeating inhalation and exhalation until the next time. Results: In this study, the difference in respiratory function according to the mask type was statistically significant except for FEV1 and FVC (p<0.05). As a result of post-hoc analysis, FVC, FEV1, PEF, and FEF values were significantly lower than those of the control group not wearing a mask (p<0.05). When wearing KF94, FVC, FEV1, PEF25-25%, and FEF were significantly lower than when wearing a dental mask (p<0.05). When wearing a KF80 mask, it was significantly lower in FVC and FEV1 than when wearing a dental mask (p<0.05). In FEV1/FVC, the difference by mask type was not statistically significant (p<0.05), but it was lower than the spirometry standard of COPD patients (FEV1/FVC<0.7). Conclusions: As Now that wearing a mask is essential, it has been confirmed that the mask affects the respiratory rate.Therefore, in the case of healthy adults, it is recommended to rest after wearing a mask if attention deficit or headache occurs. People with low breathing capacity are recommended to have low-intensity activities and frequent rest periods after wearing a mask.

• Rubber Technology
• /
• v.22 no.2
• /
• pp.119-149
• /
• 2021

Domestic materials & components industry is making a shift from quantitative growth to qualitative growth, while the paradigm of a future society is changing rapidly to energy, mobility, smartification and etc. The main features of materials & components industry are analyzed broadly based on three aspects that are: ① industry Status, ② the value chain structure, ③ the competitiveness. With regard to the national aspect, it is shown that the number of an export and a trade surplus increased consistently after the government advanced the policy on materials & components and Korea's trade deficit with Japan has been decreased. Moreover, the state's export ranking increased from tenth place in 2001 into sixth place in 2017, dedicating to the growth of a national economy. The analysis of the chain value indicates that specifications of an end product are set when the materials & components are combined with manpower, infrastructure and technologies. In terms of the competitiveness, it requires a long time and high costs to develop technologies on materials and it is important for components to have a process innovation and credibility wired. Following the industry structure with priority given on materials, Jeonnam Province accounts for 14.8% of national material production. As a result of analyzing Jeonnam's export competitiveness, it is measured that a serious polarization exists, revealing there are 6 major technology industries by 11 categories for materials & components, Jeonnam has presented 6 major materials & components considering the key industry and the new industry in future to remedy the mentioned problem so far, and plans to knock on the industry development through 10 different strategies.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.65 no.3
• /
• pp.57-67
• /
• 2023

A flash drought is a rapid-onset drought that develops over a short period of time as weather and environmental factors change rapidly, unlike general droughts, due to meteorological abnormalities. Abnormally high evapotranspiration rates and rapid declines in soil moisture increase vegetation stress. In addition, crop yields may decrease due to flash droughts during crop growth and may damage agricultural and economic ecosystems. In this study, Flash Drought Intensity Index (FDII) based on soil moisture data from Gravity Recovery Climate Experiment (GRACE) was used to analyze flash drought. FDII, which is calculated using soil moisture percentile, is expressed by multiplying two factors: the rate of intensification and the drought severity. FDII was developed for domestic flash drought events from 2014 to 2018. The flash drought that occurred in 2018, Chungcheongbuk-do showed the highest FDII. FDII was higher in heat wave flash drought than in precipitation deficit flash drought. The results of this study show that FDII is reliable flash drought analysis tool and can be applied to quantitatively analyze the characteristics of flash drought in South Korea.

• Journal of Korea Trade
• /
• v.26 no.3
• /
• pp.79-101
• /
• 2022

Purpose - The purpose of this study is to analyze and compare the international competitiveness of digital service trade between Korea and China and to help enhance the competitive advantage of digital service trade between the two countries. Design/methodology - This paper designs and establishes a comprehensive evaluation system for the international competitiveness of the Korea-China digital service trade. By using the analytical methods of combining theory and demonstration through qualitative and quantitative analysis, this paper makes a concrete and complete theoretical deconstruction and empirical measurement of its international competitiveness from the two levels of overall competitiveness and departmental competitiveness. At the same time, the study also analyzes the competitive advantages and comparative disadvantages of the two countries. Findings - It is found that South Korea has a strong competitive advantage in the sector competitiveness of digital service trade, and the export structure is reasonable and balanced, but the deficit pattern affects the overall competitiveness. China has a strong competitive advantage in the overall competitiveness of the digital service trade. However, the structural imbalance in the export sector weakens the competitiveness of the sector. Both Korea and China have the space advantage and competitive potential to enhance international competitiveness in terms of development trends. Originality/value - This paper takes the lead in solving the pain point of the relative lack of similar research topics. It demonstrates the evolution process, development trends, and structural characteristics of the digital service trade. A new combination of competitive power research methods is innovated, and a comprehensive evaluation system is established. The above innovation points show the academic theoretical value and practical application value of this study.

• Journal of Korean Neurosurgical Society
• /
• v.66 no.4
• /
• pp.400-408
• /
• 2023

Objective : Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) is a crucial factor for the survival of neuron. The role of NMNAT2 in damage following traumatic brain injury (TBI) remains unknown. This study was designed to investigate the role of NMNAT2 in TBI-induced neuronal degeneration and neurological deficits in rats. Methods : The TBI model was established in Sprague-Dawley rats by a weight-dropping method. Real-time polymerase chain reaction, western blot, immunofluorescence, Fluoro-Jade C staining, and neurological score analyses were carried out. Results : NMNAT2 mRNA and protein levels were increased in the injured-side cortex at 6 hours and peaked 12 hours after TBI. Knocking down NMNAT2 with an injection of small interfering RNA in lateral ventricle significantly exacerbated neuronal degeneration and neurological deficits after TBI, which were accompanied by increased expression of BCL-2-associated X protein (Bax). Conclusion : NMNAT2 expression is increased and NMNAT2 exhibits neuroprotective activity in the early stages after TBI, and Bax signaling pathway may be involved in the process. Thus, NMNAT2 is likely to be an important target to prevent secondary damage following TBI.