• Journal of Korean Neurosurgical Society
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• 제45권3호
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• pp.164-168
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• 2009

Objective : Bilateral C1-2 transarticular screw fixation (TAF) with interspinous wiring has been the best treatment for atlantoaxial instability (AAI). However, several factors may disturb satisfactory placement of bilateral screws. This study evaluates the usefulness of unilateral TAF when bilateral TAF is not available. Methods : Between January 2003 and December 2007, TAF was performed in 54 patients with AAI. Preoperative studies including cervical x-ray, three dimensional computed tomogram, CT angiogram, and magnetic resonance image were checked. The atlanto-dental interval (ADI) was measured in preoperative period, immediate postoperatively, and postoperative 1, 3 and 6 months. Results : Unilateral TAF was performed in 27 patients (50%). The causes of unilateral TAF were anomalous course of vertebral artery in 20 patients (74%), severe degenerative arthritis in 3 (11%), fracture of C1 in 2, hemangioblastoma in one, and screw malposition in one. The mean ADI in unilateral group was measured as 2.63 mm in immediate postoperatively, 2.61 mm in 1 month, 2.64 mm in 3 months and 2.61 mm in 6 months postoperatively. The mean ADI of bilateral group was also measured as following; 2.76 mm in immediate postoperative, 2.71 mm in 1 month, 2.73 mm in 3 months, 2.73 mm in 6 months postoperatively. Comparison of ADI measurement showed no significant difference in both groups, and moreover fusion rate was 100% in bilateral and 96.3% in unilateral group (p=0.317). Conclusion : Even though bilateral TAF is best option for AAI in biomechanical perspectives, unilateral screw fixation also can be a useful alternative in otherwise dangerous or infeasible cases through bilateral screw placement.

• Journal of Yeungnam Medical Science
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• 제29권1호
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• pp.35-37
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• 2012

Adrenal hemorrhages caused by blunt abdominal trauma have been frequently reported, and most of the lesions are unilateral. In contrast, bilateral hemorrhage of the adrenal glands after trauma rarely occurs in subjects with predisposing conditions such as coagulopathy, thromboembolism, and sepsis. Furthermore, bilateral hemorrhage of the adrenal glands is potentially fatal by inducing acute adrenal insufficiency. Here,a case of a 40-year-old man who developed traumatic bilateral adrenal hemorrhage after a car accident, without any predisposing condition, is reported. The spontaneous shrinkage of the bilateral lesions revealed in the follow-up abdominal computed tomography (CT) scansupported the aforementioned diagnosis. Fortunately, the patient had no clinical or biochemical evidence suggesting acute adrenal insufficiency. To these authors' knowledge, this is the first South Korean report of traumatic bilateral adrenal hemorrhage in a subject with no predisposing factors.

• 한국수소및신에너지학회논문집
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• 제33권5호
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• pp.470-498
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• 2022

Recently, the world has been considering hydrogen energy as the primary energy transition means to achieve carbon neutrality by 2050. In order to achieve the goal of reducing greenhouse gas emissions, Korea is also promoting a clean hydrogen economy. However, it is necessary to introduce various clean hydrogen from overseas so that the projected demand can not meet the domestically produced. For this study, we conducted the policy comparison approach between countries other than the generally considered technical and economic approaches. The finding proposes the direction of bilateral cooperation for a strategy of securing overseas clean hydrogen from a geopolitical perspective. Germany was a target country for the policy comparison since it has a high proportion of manufacturing, like Korea, and is taking the lead in the renewable-based energy transition policy. According to the survey and analysis of the policy establishment status and new projects of the two countries, Germany is promoting bilateral international cooperation in the hydrogen area with about 33 countries based on 7 types of activities. In comparison, Korea is involved in bilateral cooperation with about 12 countries on relatively few activities. Among the types of bilateral cooperation, R&D cooperation with advanced countries for hydrogen technology was a common activity type. Germany preemptively promotes cooperation for demonstration and commercialization, considering geopolitical means and strengthening manpower training and assistance on policy and regulation to preoccupy the market for the future. Therefore, it is necessary to consider establishing a network of an entire life cycle of supply and demand network that links the future market with securing clean hydrogen considering the geopolitical distribution. To this end, Korea also needs to expand bilateral cooperation countries by activity type, and it seems necessary to seek various geopolitical-based bilateral cooperation and support measures for developing countries to diversify the supply sources of hydrogen.

• Journal of Trauma and Injury
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• 제35권1호
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• pp.56-60
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• 2022

The most common cause of foot drop is lumbar degenerative disc herniation, particularly at L4/5. We present a rare case of spinal cord injury accompanied by a thoracolumbar lesion that presented with bilateral foot drop. A 69-year-old male patient presented with sudden-onset severe bilateral leg pain and bilateral foot drop. Radiologic findings revealed T12 spondylitis compressing the conus medullaris. He had undergone vertebroplasty for a T12 compression fracture after a fall 6 months before. A physical examination showed bilateral foot drop, paresthesia of both L5 dermatomes, increased deep tendon reflex, and a positive Babinski sign. An acute bilateral L5 root lesion and a conus medullaris lesion were suspected based on electromyography. A surgical procedure was done for decompression and reconstruction. After the operation, bilateral lower extremity muscle strength recovered to a good grade from the trace grade, and the patient could walk without a cane. The current case is a very rare report of bilateral foot drop associated with T12 infectious spondylitis after vertebroplasty. It is essential to keep in mind that lesions of the thoracolumbar junction can cause atypical neurological symptoms. Furthermore, understanding the conus medullaris and nerve root anatomy at the T12-L1 level will be helpful for treating patients with atypical neurological symptoms.

• Kyungpook Mathematical Journal
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• 제51권4호
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• pp.419-427
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• 2011

In this paper, making use of transformation due to S. N. Singh [21], an at-tempt has been made to establish certain results involving basic bilateral hypergeometric series and continued fractions.

• Journal of Electrical Engineering and Technology
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• 제4권3호
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• pp.346-352
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• 2009

The eventual goal of this paper is to help the generating companies and load-serving entities to choose appropriate relative levels of interconnected system versus bilateral trades while considering risk, and economic performance. In competitive power markets, electricity prices are determined by balance between demand and supply in electric power exchanges or bilateral contracts. The problem formulation is bilateral contract incorporated into Multi-area unit commitment with import/export and tie-line constraints. This proposed method considers maximizing own profit or minimize the operating cost among the generating companies in multi-area system. The feasibility of the proposed algorithm has been demonstrated using IEEE system with four areas and experimental results shows that proposed method is reliable, fast and computationally efficient

• Korean Journal of Mathematics
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• 제23권4호
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• pp.665-732
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• 2015

Existence results for multiple positive solutions of two classes of boundary value problems for bilateral difference systems are established by using a fixed point theorem under convenient assumptions. It is the purpose of this paper to show that the approach to get positive solutions of boundary value problems of finite difference equations by using multi-fixed-point theorems can be extended to treat the bilateral difference systems with one-dimensional Laplacians. As an application, the sufficient conditions are established for finding multiple positive homoclinic solutions of a bilateral difference system. The methods used in this paper may be useful for numerical simulation. An example is presented to illustrate the main theorems. Further studies are proposed at the end of the paper.

• 동의생리병리학회지
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• 제18권2호
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• pp.621-625
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• 2004

Bilateral striopallidodentate calcinosis, popularly referred to as Fahr's disease, is a disorder radiologically characterized by bilateral calcifications of the basal ganglia, thalami, dentate nuclei of the cerebellum, and the white matter of the cerebral hemisphere without serum calcium-phosphorus metabolism and related endocrinologic abnormalities. Intracranial calcifications are easily visible as high-density on CT. On magnetic resonance images, the calcifications exhibit different signal intensities. The differences in signal intensity are thought to be related to the stage of the disease, differences in calcium metabolism, and the volume of the calcium deposit. Based on literature review, I report the case of a 63 year man with bilateral symmetrical calcification in the basal ganglia, dentate nuclei of the cerebellum, and the white matter of the cerebral hemisphere who present a 5 year history of progressive dysarthria associated with left thalamic infarction.

• Journal of Korean Neurosurgical Society
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• 제51권6호
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• pp.388-390
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• 2012

There has been no report of bilateral pedicle stress fractures involving two vertebrae. The authors describe a unique case of spondylolisthesis accompanying a bilateral pedicle stress fracture involving two vertebrae. De novo development of spondylolisthesis at the L5-S1 vertebrae accompanying a bilateral pedicle stress fracture at L4 and L5 was observed in a 70-year-old woman. The patient's medical history was unremarkable and she did not have any predisposing factors except severe osteoporosis. Interbody fusion with bone cement augmented screw fixation was performed. Surgical treatment resulted in good pain management and improved functional recovery.

• Asian Journal of Business Environment
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• 제6권1호
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• pp.19-24
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• 2016

Purpose - This paper aims to find and analyze factors that determine the flows of bilateral foreign direct investment in intra-ASEAN. It specifically focuses on the dimension of macro-economic, natural resources, human resources, and the quality of governance. Research design, data, and methodology - Data were collected from 64 bilateral relations between ASEAN nations from 2002 to 2013. Panel gravity model was utilized to find factors that determine the flows of bilateral foreign direct investment. Results - Significant factors were identified that determine the flows of bilateral foreign direct investment: GDP home country, GDP host country, real interest rate, distance, and total natural resources rent. Unexpectedly, natural resources have a negative effect. Conclusions - In a situation of increasing the flow of FDI among the countries of ASEAN, the government should control the interest rates and maintain good relations with nearby countries. The negative effect of total natural resource rents implies that ASEAN countries should not depend on their natural resources to attract foreign investments.