• Journal of Chest Surgery
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• v.43 no.5
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• pp.542-545
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• 2010

Extramedullary hematopoiesis is a common compensatory mechanism of chronic anemia, but an asymptomatic posterior mediastinal mass is rarely diagnosed as an extramedullary hematopoiesis after surgical resection. The differential from neurogenic tumors is important, but fine needle aspiration biopsy is not recommended because of the difficulty of approach and risk of bleeding. Although diagnosis and treatment can involve resection via thoracotomy, video-assisted thoracic surgery may also be a useful strategy. We performed video-assisted thoracic surgery on a 59-year-old man for posterior mediastinal extramedullary hematopoiesis, with no evidence of recurrence or related hematologic diseases.

• Resources Recycling
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• v.8 no.3
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• pp.18-25
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• 1999

The study on the electrosorption of cobalt ions onto a porous activated carbon fiber (ACF) was performed to treat radioactive liquid wastes resulting from chemical or electrochemical decontamination and to regenerate the spent carbon electrode, Cyclic voltammetry was investigated on a rotating-disk electrode (RDE) to determine the region of potentials within which only double-layer charging should occur. The application of an electric potential increased the sorption of the cobalt ions. The adsorbed cobalt Ions could be released into the solution by reversing the appling potential, showing the reversibility of the process.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.4
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• pp.36-45
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• 2014

Model based control methods are widely used to improve the control performance of diesel engine air systems because the control results of the air system significantly affect the emission level and drivability. However, the model based control algorithm requires a lot of unmeasurable states which are hard to be measured in a mass production engine. In this study, an air system model of the diesel engine is proposed to estimate 11 unmeasurable states using only sensors equipped in a mass production engine. In order to improve the estimation performance in the transient condition, dynamic characteristics of the air system are analyzed and implemented as discrete filters. Turbine and compressor efficiency models are also proposed to overcome a limitation of the constant or look-up table based efficiency values. The proposed air system model was validated in steady state and transient conditions by real-time engine experiments. The maximum error of the estimation for 11 physical states was 11.7%.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.6 no.1
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• pp.38-44
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• 2013

The ultrasound can be used primarily to guide exact needle placement for aspirations of fluids, injections of steroid, and biopsies in musculoskeletal field. Recently, ultrasound-guided intervention is widely used because of several advantages such as real-time performance, relatively inexpensiveness, and getting multiple images without additional radiations. However, the modality is operator dependent and requires detailed knowledge of the relevant anatomy and there have been also reported serious complications related to the procedure. So, authors will discuss about the basic techniques, principles and cautions for the use of ultrasound-guided intervention in musculoskeletal field.

• Korean Journal of Head & Neck Oncology
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• v.21 no.2
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• pp.170-173
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• 2005

Fine needle aspiration cytology (FNAC) of thyroid gland lesions has become a routine diagnostic method. And fine needle aspiration cytology is considered a safe, reliable and cost-effective means of selecting thyroid nodules with risk for malignancy. However, fine needle aspiration cytology of the thyroid may cause hemorrhage, infection, or trauma to adjacent structures. Hemorrhage sufficient to cause tracheal compression has not been reported. So we present a case of anterior neck hematoma causing tracheal compression after FNAC of the thyroid nodule.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.28 no.2
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• pp.144-147
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• 2017

Laryngeal neoplasm is the second most common malignancy of the upper aerodigestive tract. About 85% to 95% of laryngeal malignancies are squamous cell carcinoma that arises from the epithelial lining of the larynx. The exact cause of laryngeal neoplasm is unknown, but certain risk factors can affect the chances of developing it. Chronic inflammation is a mutagen factor confirmed in the carcinogenesis of various tumor. Inhalation injuries cause histopathologic damage to laryngeal mucosa and inflammation change. This long term inflammation may leads to the development of dysplasia and malignant transformation. Recently, we experienced a case of malignant transformation of laryngeal mucosa after inhalation injury patient 25 years ago. Herein, we reported this rare case and review the relevant literature.

• Journal of Home Health Care Nursing
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• v.22 no.1
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• pp.88-97
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• 2015

Purpose: This study was conducted to identify the effects of a suction care self video-based debriefing-assisted learning in the fundamentals of nursing practice for nursing students on clinical performance, self-efficacy and problem-solving process. Methods: A nonequivalent control group non-synchronized design study was used and included 97 junior nursing students at P University as participants, 48 of whom were assigned to the experimental group, and 49 of whom were assigned to the control group. The outcome measurements were clinical performance for suction care, self-efficacy, and the problem-solving process. Results: The scores of clinical performance were 23.75 in the experimental group who used the materials and 21.55 in the control group, and the difference was statistically significant (p<.000). Self-efficacy was 4.30 in the experimental group and 4.18 in the control group, which was a statistically significant difference (p=.000), and the pre-to-post differences of self-efficacy was statistically significant as well (p<.001). However, there were no significant differences in the pre-to-post differences of the problem-solving process (p<.802). Conclusions: Self video-based debriefing-assisted learning may be more effective in enhancing clinical performance and self-efficacy than that of conventional practice. Whether self-efficacy will contribute to enhanced learning motivation for nursing students needs further examination.

• The Korean Journal of Cytopathology
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• v.5 no.2
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• pp.184-188
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• 1994

Therapeutic management of brain tumors is based on accurate knowledge of their size, location and histologic type. Stereotaxic cytology under CT guidance has been applied to the investigation of brain tumors, especially in the sellar turcica, third ventricle, and pineal regions. In the present case, the tumor protruded into the nasal cavity, so we were able to get cytologic material via fine needle aspiration. Although pituitary adenoma is not an unsual tumor, there have been few reports about its cytologic features. We present the cyotologic and histologic features of a case of pituitary adenoma with immunohistochemical study.

• Applied Chemistry for Engineering
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• v.1 no.1
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• pp.30-34
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• 1990

This paper summarizes fundamental research on a metal hydrides for the development of new energy. We made a study of the characteristics of the hydrogen absorption-desorption of $DiNi_5$ alloys. As a result, we found that the maximum amount of the hydrogen absorption of $DiNi_5$ alloys (the maximum in the absorption equilibrium pressure section) was H/M=1.04 at $30^{\circ}C$. The hysteresis was the smallest at $30^{\circ}C$. The capability of the hydrogen absorption-desorption was excellent. The number of cycles of the hydrogen absorption-desorption was about 9000 times at $30^{\circ}C$. We found also that the rate of the hydrogen desorption was the largest at $40^{\circ}C$.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.110-111
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• 2014

RGB laser 를 이용하여 rf-magnetron sputtering 법으로 합성한 a-IGZO 박막의 photoresponse 를 관찰하였다. Air 분위기에서 red 파장을 조사 할 경우 비교적 slow recovery 특성을 보였으며, green 과 blue 파장을 조사 할 경우 red 보다 fast recovery 특성을 나타내었다. 그러나 진공에서 측정할 경우, red 파장에서는 recovery 가 빨라졌으며, green 과 blue 파장의 경우 recovery 가 매우 느려짐을 확인하였다. 이는 passivation 을 하지 않은 소자의 oxygen gas 의 흡/탈착 때문으로 예상할 수 있었으며, red 파장이 gas 탈착에 기여하는 정도가 매우 작고, green 과 blue 파장이 gas 탈착에 기여하는 정도가 매우 크기 때문인 것으로 생각할 수 있었다. 온도를 증가시킬 경우, 모든 경우에서 recovery 가 빠르게 나타났는데 이는 흡/탈착에 필요한 barrier 및 $V_o{^{2+}}$에서 Vo 로 돌아오기 위한 barrier 를 쉽게 넘어갈 수 있기 때문으로 이해 할 수 있었다. 이러한 결과를 stretched exponential equation 을 이용하여 해석하였으며 수치화 하였다.