• Journal of Pharmaceutical Investigation
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• 제23권4호
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• pp.225-229
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• 1993

The stability of omeprazole in the aqueous solutions containing arginine or sodium phosphate dibasic(SPD) was examined at 30, 40 and $50^{\circ}C$. Arginine or anhydrous SPD was added to omeprazoie solution ($200{\mu}g/\;ml$ in distilled water) to yield $100{\mu}g/\;ml$ concentration of each. Then, the solution was kept at 30, 40 or $50^{\circ}C$ for 90 hrs. Aliquots of the solution were withdrawn at specified time intervals and assayed by HPLC for intact omeprazole. The remaining percentage-time curves revealed that omeprazole was degraded rapidly as funtions of time and temperature following pseudo first-order kinetics. The rate constant in the SPD solution was much higher than in the arginine solution. In other words. the degradation half-lives of omeprazole at $30^{\circ}C$, for example, was 148 and 76 hr in arginine and SPD solutions respectively. The initial pH of the solution containing $100{\mu}g/\;ml$ of arginine or SPD was 9.7 or 8.7, respectively. Since omeprazole is more stable as the pH of its solution becomes more alkaline, the longer half-life of omeprazole in arginine solution could be explained by the more alkaline characteristics of arginine than SPD in the solution. The activation energy necessary for the degradation reaction was almost identical in both solutions, indicating similar degradation mechanisms of omeprazole in the solutions. In conclusion, omprazole was more stable in the presence of arginine than of SPD.

• 한국산학기술학회논문지
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• 제10권7호
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• pp.1729-1734
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• 2009

해마다 전 세계적으로 약 4천만 대, 우리나라에서는 약 55만 대의 자동차가 그 수명을 다하고 폐차장으로 보내지고 있다. 폐차에 의한 환경오염을 줄이기 위하여 각 국은 규제를 강화하고 있으며 EU(European Union)에서는 현재 84%에 머무르고 있는 재활용율을 2015년까지 95%로 올릴 것을 요구하고 있다. 자동차 중량의 75%를 차지하는 철은 95% 이상의 높은 재활용율을 보이고 있으나 나머지 25%를 구성하는 플라스틱, 유리 고무 등의 비금속류와 구리, 니켈 알루미늄 등의 비철금속류는 재활용율이 이에 미치지 못하고 있다. 따라서 95%의 재활용 요구를 만족시키기 위해서는 비철금속류의 재활용이 획기적으로 향상되어야 한다. 본 논문에서는 자동차에서 가장 많이 사용되는 비철금속인 구리와 니켈 재활용 향상을 통하여 전체 재활용율 변동을 산출하고자 한다.

• Childhood Kidney Diseases
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• 제14권1호
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• pp.1-9
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• 2010

긴 잔여 수명을 가진 소아-청소년기에 발생한 만성 콩팥병의 진행을 억제하는 것은 매우 중요하다. 콩팥 기능의 변화는 공식을 이용하여 혈청 크레아틴이나 시스타틴 C 치를 이용한 사구체 여과율의 추정치를 계산하는 것이 비교적 정확하고 편리하다. 고혈압과 단백뇨는 엄격하게 조절되어야 하며 빈혈은 에리트로포이에틴으로 교정되어야 한다. 혈압이 정상인 경우에도 특별한 금기사항이 없는 한 ACE 억제제나 안지오텐신 수용체 차단제를 사용하는 것이 필요하나 부작용의 발생에 주의할 필요가 있다. 만성 콩팥병의 진행 억제를 위한 노력은 만성 콩팥병이 확인되는 대로 가능한 일찍 시작되어야 하며 콩팥 이식을 받을 때까지 잔여 신기능이 남아 있는 한 계속되어야 한다. 온라인 한국 소아 만성 콩팥병 등록 시스템이 만성 콩팥병의 진료에 도움을 준다.

• 비교문화연구
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• 제31권
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• pp.155-175
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• 2013

Meantime there has been a tendency to keep silent about the role of Afro-Ibero America Diaspora which contributed to the spirit of independence and the realization of country foundation ideology in the official history of Latin America. In some countries, although the collective resistance of Afro-Ibero America Diaspora, which intended to establish a liberal and equal society resisting against slavery and colonization system, was the foundation of independence and the establishment of a new country, their contribution has been difficult to leave an official trace in Caucasian criollo-centered history system. Along with the development of Hcienda in 17th Century, black slaves' collective resistance was developed mainly with el Virreinato de la Nueva Granada, the center of the Independence movement of Brazil and South America. The black people who escaped resisting against slavery formed communities and developed organized activities through various politics and social activities. However, such communities were mostly dispersed or destroyed by the colonial power, and the collective resistance of Afro-Ibero America Diaspora lost life. On the other side, in case of Colombia, a community of escaped black slaves which was formed in the early 17th Century is solely remaining in Latin America, moreover, Afro-Ibero America Diaspora's struggle for liberty and equality became the foundation for Comuneros revolution and Independence movement in the late 18th Century. Comuneros revolution which occurred in 1781 awoke self-awareness of liberty and equality, and became an ideological base for independence movement based on revolutional republicanism and philosophy of enlightenment. It is considered that South America's independence movement lead by $Sim{\acute{o}}n$ Boívar was a history that could not have started without historical base of Afro-Ibero America Diaspora's resistance against colonization system. Therefore, this study intends to discuss the role and achievement of Afro-Ibero America Diaspora in the process of independence of Latin America mainly with Colombia, which is the center of Independence movement of South America. Through this process, this study intends to revaluate historical contribution of Afro-Ibero America which has been relatively neglected meanwhile in the process of independence and the establishment of country.

• 한국기계가공학회지
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• 제18권9호
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• pp.29-35
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• 2019

The structure of the machinery industry due to the 4th industrial revolution is changing from precision and durability to intelligent and smart machinery through sensing and interconnection(IoT). There is a growing need for research on prognostics and health management(PHM) that can prevent abnormalities in processing machines and accurately predict and diagnose conditions. PHM is a technology that monitors the condition of a mechanical system, diagnoses signs of failure, and predicts the remaining life of the object. In this study, the vibration generated during machining is measured and a classification algorithm for normal and fault signals is developed. Arbitrary fault signal is collected by changing the conditions of un stable supply cutting oil and fixing jig. The signal processing is performed to apply the measured signal to the learning model. The sampling rate is changed for high speed operation and performed machine learning using raw signal without FFT. The fault classification algorithm for 1D convolution neural network composed of 2 convolution layers is developed.

• Smart Structures and Systems
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• 제23권3호
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• pp.263-278
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• 2019

Moving train load parameters, including train speed, axle spacing, gross train weight and axle weights, are identified based on strain-monitoring data. In this paper, according to influence line theory, the classic moving force identification method is enhanced to handle time-varying velocity of the train. First, the moments that the axles move through a set of fixed points are identified from a series of pulses extracted from the second derivative of the structural strain response. Subsequently, the train speed and axle spacing are identified. In addition, based on the fact that the integral area of the structural strain response is a constant under a unit force at a unit speed, the gross train weight can be obtained from the integral area of the measured strain response. Meanwhile, the corrected second derivative peak values, in which the effect of time-varying velocity is eliminated, are selected to distribute the gross train weight. Hence the axle weights could be identified. Afterwards, numerical simulations are employed to verify the proposed method and investigate the effect of the sampling frequency on the identification accuracy. Eventually, the method is verified using the real-time strain data of a continuous steel truss railway bridge. Results show that train speed, axle spacing and gross train weight can be accurately identified in the time domain. However, only the approximate values of the axle weights could be obtained with the updated method. The identified results can provide reliable reference for determining fatigue deterioration and predicting the remaining service life of railway bridges.

• 대한통합의학회지
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• 제9권4호
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• pp.49-58
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• 2021

Purpose : This study investigates the effects of the application of traditional occupational therapy and the korean computerized cognition training system on the cognitive function and performance of daily activities of stroke patients with cognitive impairment. Methods : From inpatients referred for rehabilitation treatment at L Rehabilitation Hospital located in Busan, 20 patients diagnosed with stroke from April 05. 2021 to May 02. 2021 (study period) were selected, They were divided into two, an experimental group consisting of 10 subjects who underwent a computerized cognitive rehabilitation program and traditional occupational therapy in combination and a control group of 10 subjects who underwent traditional occupational therapy alone. In order to measure the cognitive function of the subjects before the intervention, two assessment tests were conducted: a Neurobehavioral Cognitive Status Examination (NCSE), which evaluates stroke-related cognitive ability, and a Functional Independence Measure (FIM) test, which evaluates life activities. Then, both groups received a total of 20 training sessions at 30 minutes per session, five times a week for four weeks. Results : A statistically significant difference was found in cognitive function between before and after the cognitive training for both the experimental group and the control group. For the FIM scores, statistically significant differences were observed after intervention in the categories of handling personal matters and social cognition, and in the total score. The average scores of the remaining items also improved. Conclusion : The results of this study showed that both the computerized cognition rehabilitation program and the traditional occupational therapy had a positive effect on the improvement of cognitive function in stroke patients.

• Journal of Chest Surgery
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• 제54권1호
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• pp.59-64
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• 2021

Background: Diaphragmatic injuries following blunt or penetrating thoraco-abdominal trauma are rare, but can be life-threatening. Rib fractures are the most common associated injury in patients with a traumatic diaphragmatic injury (TDI). We hypothesized that the pattern of rib fracture injuries could dictate the likelihood of acute TDIs. Methods: A retrospective study was carried out between April 2014 and October 2018 to analyze patients with TDIs and rib fractures at a major trauma center in London, United Kingdom. Results: Over the study period, 1,560 patients had rib fractures, of whom 14 had associated diaphragmatic injuries. Left-sided diaphragmatic injuries were found in 8 patients (57%). A significant proportion of the rib fractures were located posterolaterally (44.9%). The highest frequency of fractures was found in ribs 5-10, which accounted for 74% of all the fractures. Ten patients underwent surgery, of whom 7 were diagnosed with a diaphragmatic injury intraoperatively after video-assisted thoracoscopic surgery assessment of the pleural cavity. Two patients died due to severe injuries of other organs and the remaining 2 patients were managed conservatively. Conclusion: Our series of patients demonstrates a relationship between significant rib fractures and diaphragmatic injuries in trauma patients, and the diagnostic difficulties in identifying the condition. We found that the location of the rib fractures and the pattern of injury in patients with TDIs were much lower and posterolateral in the chest wall without a preference for laterality. We suggest using a thoracoscope in patients undergoing chest wall surgery post-trauma to aid in diagnosing this condition.

• 전력전자학회논문지
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• 제26권3호
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• pp.192-198
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• 2021

The battery's State of Health (SOH) is a critical parameter in the process of battery use, as it represents the Remaining Useful Life (RUL) of the battery. Electrochemical Impedance Spectroscopy (EIS) is a widely used technique in observing the state of the battery. The measured impedance at certain frequencies can be used to evaluate the state of the battery, as it is intimately tied to the underlying chemical reactions. In this work, a low-cost portable EIS instrument is developed on the basis of the ARM Cortex-M4 Microcontroller Unit (MCU) for measuring the impedance spectrum of Li-ion battery packs. The MCU uses a built-in DAC module to generate the sinusoidal sweep perturbation signal. Moreover, it performs the dual-channel acquisition of voltage and current signals, calculates impedance using a Digital Lock-in Amplifier (DLA), and transmits the result to a PC. By using LabVIEW, an interface was developed with the real-time display of the EIS information. The developed instrument was suitable for measuring the impedance spectrum of the battery pack up to 1000 V. The measurement frequency range of the instrument was from 1 hz to 1 Khz. Then, to prove the performance of the developed system, the impedance of a Samsung SM3 battery pack and a Bexel pouch module were measured and compared with those obtained by the commercial instrument.

• 한국압력기기공학회 논문집
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• 제16권2호
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• pp.1-9
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• 2020

Large-scale industrial facility structures continue to deteriorate due to the effects of operating and environmental conditions. The problems of these industrial facilities are potentially causing economic losses, environmental pollution, casualties, and national losses. Accordingly, in order to prevent disaster accidents of large structures in advance, the necessity of diagnosing structures using non-destructive inspection techniques is being highlighted. The defect occurrence, location and defect type of the structure are important parameters for predicting the remaining life of the structure, so continuous defect observation is very important. Recently, many researchers have been actively researching real-time monitoring technology to solve these problems. Structure Health Monitoring Inspection is a technology that can identify and respond to the occurrence of defects in real time, but there is a limit to check the degree of defects and the direction of growth of defects. In order to compensate for the shortcomings of these technologies, the importance of defect imaging techniques is emerging, and in order to find defects in large structures, a method of inspecting a wide range using guided ultrasonic is effective. The work presented here introduces a calculation for the shape factor for evaluation of the damaged area, as well as a variable β parameter technique to correct a damaged shape. Also, we perform research in modeling simulation and an experiment for comparison with a suggested inspection method and verify its validity. The curved structure image obtained by the advanced RAPID algorithm showed a good match between the defect area and the shape.