• Journal of the Korea Society of Computer and Information
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• v.16 no.2
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• pp.153-163
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• 2011

Smartphone is a mobile device which can perform better than feature phone. Recently, growth in demand for advanced mobile devices boasting powerful performance, market share of smartphone is increasing rapidly in mobile device market, for example, iphone and android phone. Smartphone can provide many functionalities, e-mail, scheduler, word-processing, 3D-game, and etc, based on its powerful performance. Thus, various secret information is integrated in smartphone. To provide service, sometimes, smartphone transmits informations to outside via wireless network. Because smartphone is a mobile device, user can lose his/her smartphone, easily, and losing smartphone can cause serious security threats, because of integrated information in smartphone. Also data which is transmitted in wireless network can be protected for privacy. Thus, in present, it is very important to keep secure smartphone. In this paper, we analyze threats and vulnerabilities of smartphone based on its environments and describe countermeasures against threats and vulnerabilities.

• Tuberculosis and Respiratory Diseases
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• v.41 no.1
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• pp.58-62
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• 1994

Superior vena cava(SVC) syndrome is mostly related to a malignant process, but many different benign causes have also been described. We report a case of SVC syndrome caused by Klebsiella pneumonia diagnosed by sputum culture and serial chest X-ray changes. A 27-year-old man had been in stable health until three days before admission, when he complained of pleuritic chest pain, facial flushing, and shortness of breath. Examination of the head and neck disclosed edema of face and both arms, and jugular venous distention to the angle of the jaw. The chest auscultation revealed decreased breath sound without crack1e on right upper lung field. The chest roentgenogram showed homogenous air space consolidation on right upper lobe, asociated with downward displacement of minor fissure and contralateral displacement of trachea, but air bronchogram was not seen. We began antibiotic therapy under impression of pneumonia after available culture was taken from blood and sputum. SVC scintigraphy showed stasis of drain of right brachiocephalic vein at the proximal portion with reflux into the right internal jugular vein and faintly visible SVC via the collaterals. Sputum culture revealed Klebsiella pneumoniae. Antibiotic therapy resulted in a cure of infection and disappearance of facial swelling. Follow-up SVC scintigraphy after 20 days showed normal finding. We first report a case of SVC syndrome caused by klebsiella pneunonia.

• Tuberculosis and Respiratory Diseases
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• v.64 no.4
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• pp.303-308
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• 2008

Benign bronchoesophageal fistula is a rare disease and it may be characterized by nonspecific symptoms that can cause a delayed diagnosis. We misdiagnosed a patient with recurrent aspiration, which was due to bronchoesophageal fistula, as active pulmonary tuberculosis. The patient was 44 year old female who had suffered from chronic cough, especially during eating liquid meals, since 1982 when she had been treated for tuberculous lymphadenitis. Computed tomography showed an irregular mass with surrounding centrilobular nodules in the superior segment of the right lower lobe (RLL). She was diagnosed as having active pulmonary tuberculosis and treated with anti-tuberculosis medication, but she continued to complain of persistent cough even after anti-tuberculosis treatment. Thus, we reexamined the patient, and bronchoesophageal fistula between the esophagus and the superior segment of the RLL was finally confirmed by esophagography. After the fistula was surgically treated, the patient became asymptomatic and she then experienced good health.

• Korean Journal of Applied Biomechanics
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• v.19 no.3
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• pp.435-448
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• 2009

The purpose of this study was to investigate the kinemaitc gait parameter of lower extremities with different gait conditions(level walking, stairs, ramp) in old adults. Fourteen healthy older adults participated in this study and kinematic data were measured using 3D motion analysis system(Vicon, Oxford Metrics, England). Statistical analysis was used one-way ANOVA to know the difference of lower extremities angle at each gait phase with a different gait conditions. In sagittal plane, pelvic anterior tilt increased in stairs and ramp climbing and hip and knee flexion increased in stairs climbing but ankle dorsiflexion increased in ramp climbing. In frontal plane, pelvic was up in stairs and hip abduction and adduction more changed in stairs climbing than level walking. Knee varus and ankle inversion increased in stair climbing. In horizontal plane, pelvic internal rotation increased in stairs and ramp climbing and knee internal rotation increased in stairs climbing but ankle external rotation increased in stairs climbing. This results was shown that the stairs and ramp climbing changed the kinematic gait parameters of lower extremities in healthy old adults.

• Radiation Oncology Journal
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• v.12 no.1
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• pp.43-50
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• 1994

A retrospective analysis was performed on 55 patients with malignant parotid tumor who were treated with radiation therapy between March, 1979 and July, 1989. Of these patients, 8 patients received radiation therapy(RT) alone and 47 patients were treated with combined operation and radiation therapy(OP + RT). The follow-up period of the survivors ranged from 1 to 129 months with a median of 48 months. The common histologic types were mucoepidermoid carcinoma (25 cases), malignant mixed tumor(12 cases), adenoid cystic carcinoma(6 cases). The 5 and 10 year local control rate were 69.8% and 65.7% in all patients. In OP+RT group, prognostic factors related to local control were histologic grade, tumor size, lymph node metastasis. Resection of facial nerve did not affect the local control rate significantly(p=0.129). Distant metastasis developed in 23.6% of patients, mostly to the lung. Actuarial overall survival rate was 72.2% at 10 years and formed plateau after 5 years. Disease-free (NED) survival rate was 49.4% at 10 years and was better achieved in OP+RT group and low grade lesions. Based on our result, a well planned postoperative RT following parotidectomy is highly efficacious in controlling malignant tumors of the parotid gland and preservation of facial nerve.

• Archives of Plastic Surgery
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• v.35 no.1
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• pp.48-55
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• 2008

Purpose: We measured linear distances, angles and inclinations on the cast models of the noses, and compared these indirect measurements with the direct measurements obtained from the nose in order to validate the accuracy of the indirect anthropometry using the cast model. Methods: Subjects were 50 males and 50 females, medical students in twenties(mean 27.1 years). Cast models were made from the alginate impression material and the plaster. In direct anthropometry, 16 linear, 7 angular, and 2 inclination measurements between 11 landmarks on the nose were obtained using sliding caliper, spreading caliper, and fabric tape measure. At the same time, the same measurements were obtained from the cast models of the same people. Total 25 measurements were compared, and tested by the independent t-test of SPSS. Results: The standard values of Korean nose in twenties were obtained. 24 measurements except the columellar labial angle were not statistically different between the indirect anthropometry and the direct anthropometry. Conclusion: Indirect anthropometry on the cast model of the nose revealed no significant difference from the anthropometric measurement statistically, accounting for 24 in 25 measurements(96%). There are two possible reasons that caused the difference of columellar labial angle between direct and indirect anthropometry. First, the columellar labial angle could be decreased by protrusion of the lips which resulted from contracting mouth in which an drinking straw had been applied on the mouth corner for patients' respiration during making cast model. Second, it is generally known that the columellar labial angle could be measured larger when soft tissues were pressed by protractor in direct anthropometry. Using a drinking straw with greater diameter, and scheming respiration through the nostrils that patients don't feel discomfort, the more accurate data would be obtained from the indirect anthropometry using the cast models of the noses.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.177-184
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• 1998

Purpose : Radiotherapy has been the mainstay of the treatment of brain metastases. We evaluated the response rate, survival and prognostic factors of patients with brain metastases treated with radiotherapy for palliative purpose. Materials and Methods : From January 1994 through April 1997, in all 42 patients, a retrospective analysis was undertaken. Of these, 33 patients received whole brain irradiation with 30Gy in 10 daily fractions with or without a boost of 10Gy in 5 daily fractions to the site of solitary lesion. Nine patients failed to complete the planned treatment Results : Of 33 patients who finished radiotherapy, complete and partial response were observed in $4(12\%)$ patients and $22(67\%)$ ones, respectively. Overall response rate was $79\%$ and median survival was 4 months. In univariate analysis, prognostic factors affecting survival were initial neurologic function class(p=0.0136), extracranial tumor activity(p=0.042), and response after radiotherapy(p=0.001). Conclusion : We confirmed that whole brain irradiation is the effective means for treating the patient with brain metastases. initial neurologic function class, extracranial tumor activity, and response alter radiotherapy were identified as prognostic factors affecting survival.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.6
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• pp.455-467
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• 2017

In this study, a finite element analysis of a cylindrical multi-pass weldment for dissimilar metals was performed. The effects of the heat input method and weld bead generation method were considered. We compared two heat input methods: the heat flux method and the temperature method. We also compared two weld bead generation methods: the element birth method and the quiet element method. Although the results of the thermal analysis show deviations between the two heat input methods, the welding residual stresses were similar. Because the areas exposed to high temperature were similar and the strength of the material was very low in high temperature (above the $1000^{\circ}C$), the effects of the weld bead temperature were insignificant. The distributions of the welding residual stress were similar to each other. However, gaps and overlaps occurred on the welding boundary surfaces when the element birth method was applied. The quiet element method is more suitable for a large deformation model in order to simulate a more accurate weld shape.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.433-437
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• 2007

최근 환경부에서는 낙동강 유역의 오염총량관리제도의 시행에 따라 이제까지의 배출구 수질기준으로부터 총량수질기준을 통한 수질관리를 실시하고 있다. 오염총량관리를 실행하기 위해서는 주요지천 및 폐수처리장에서의 수질개선 및 비점오염원 관리가 선행되어야 하는데 이를 효율적으로 제어하기 위해서 낙동강 유역에 적합한 최적 수질해석 모델의 개발이 요구되는 상황이다. 수질모델의 가장 큰 목적은 유역으로부터 발생한 오염물이 하천으로 유입되었을 때 하천 수질 및 생태계의 수학적 표현을 통해 장래의 수질을 예측하고, 예측된 결과에 따라 합리적인 수질관리대책을 수립하는 것이다. 낙동강은 대표적인 수지상 하천망의 형태로서 댐 방류량 및 지류유입량은 본류 수계에 직접적인 영향을 미치며, 수질해석의 기본이 되는 수리계산에 매우 중요한 변수가 된다. 또한 대구, 구미, 왜관, 김천 등에서의 오염부하가 금호강, 남강 등의 주요 지류를 통하여 본류부로 유입되고 있으며, 하류부 칠서, 원동, 매리, 물금 등에서는 대량의 하천수를 취수하여 부산, 울산, 마산, 창원 지역 등의 생활 및 공업용수의 원수로 사용하고 있다. 다시 말해서 댐 방류량, 낙동강 하구언의 수위조절, 지류 유입량, 비점원 유입량 등 계산영역 경계에서의 비정상상태의 수리조건과 수질관리 계획에 의해 일률적으로 오염이 부하되는 정상상태의 수질조건이 공존하고 있는 실정이다. 본 연구에서는 낙동강 유역에 적합한 동적 수질모델을 개발하였다. 본 연구에서 개발된 수치모형은 갈수저수조건 및 불규칙한 하도단면을 반영하고, 동적 상태의 댐 방류량, 낙동강 하구언의 수위조절 영향, 지류 유입량 등 다양한 하천조건에서 발생하는 동적 흐름을 안정적으로 해석하여 낙동강 수질해석의 신뢰도를 향상시킴으로서 낙동강에 유입된 오염물질이 수계에 미치는 영향을 정확히 분석하고자 하였다. 동적수질해석에 의한 모의결과는 유량의 경우 상류부분은 모의치와 실측치가 잘 일치하지만, 중류 이후 지류의 유입이 많아지면서 지류의 변화를 정확히 입력하지 못해 모의치와 실측치의 차이가 발생한다. BOD의 경우는 수질이 양호한 상류지역은 모의치와 실측치가 잘 일치하지만, 오염원의 유입이 많은 중류지역부터는 실측치와 차이를 나타내다가 하류지역에서 다시 비교적 일치함을 알 수 있다. TN의 경우는 전반적으로 실측치보다 높게 모의되었고, TP는 전반적으로 실측치와 비교하여 잘 모의되었다. 본 연구에서 구축한 동적 수리해석모형 및 동적 수질해석모형은 낙동강 유역에 대해 유량 및 수질 등의 실제 하천의 경향에 비교적 잘 반영하므로 오염물총량규제에 따른 합리적인 하천 수질관리대책을 수립하는데 크게 기여할 수 있을 것으로 기대된다.

• Economic and Environmental Geology
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• v.25 no.1
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• pp.1-16
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• 1992

The Wondong Fe-Pb-Zn deposit is located in endo and exoskarns formed along the contact between the Makkol limestone interbedding pelitic limestone of Ordovician age and quartz porphyry of Cretaceous age. At the Wondong mine, the endoskarn shows a discontinuous zonal arrangement from quartz porphyry to pelitic limestone as follows: unaltered quartz porphyry, weakly altered quartz porphyry zone, intensively altered pinkish quartz porphyry zone, garnet zone, and greyish white and fine-grained clinopyroxene zone developed at pelitic limestone side. In terms of chemical mass balance, intensively altered pinkish quartz porphyry relative to unaltered quartz porphyry shows substantial enrichments in $K_2O$, $Na_2O$, and HREE and depletions in MgO, CaO, total $Fe_2O_3$, and LREE. On the other hand, garnet zone of endoskarn is enriched in CaO, MnO, total $Fe_2O_3$, MgO and depleted in $K_2O$, $Na_2O$. $Al_2O_3$ seems to be determining inert component. Thus the behavior of elements indicates that the mobility of elements depends on the equilibration of hydrothermal fluid and minerals and affects on enrichments by fractionation from and depletions by partition to hydrothermal fluid, respectively. Traversing toward pelitic limestone from a central zone of exoskarn, the exoskarn also shows a zonal arrangement as follows: garnet zone, clinopyroxene zone, and decolored pelitic limestone. The arrangement of mineral assemblages in skarns of the Wondong mine is the result of an increase in CaO and $K_2O$ toward the pelitic limestone. Skarn and ore minerals were formed in the following sequence: early skarn, late skarn and magnetite, pyrite, sphalerite, galena, and molybdenite. On the basis of stabilities of mineral assemblages, physicochemical conditions of the late skarn and magnetite mineralization are estimated to be $350^{\circ}C{\leq}T{\leq}400^{\circ}C$ at 1 Kb, $-23{\leq}log\;fO_2{\leq}-18$, and $0.005{\leq}XCO_2{\leq}0.01$, while those of the early skarn to be $420^{\circ}C{\leq}T{\leq}550^{\circ}C$ at 1 Kb.