• Title/Summary/Keyword: Medical Engineering

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A Study on the Resolution Analysis of Digital X-ray Images with increasing Thickness of PMMA (조직 등가물질 두께 증가에 따른 디지털 엑스선 영상의 해상도 분석에 관한 연구)

  • Kim, Junwoo
    • Journal of the Korean Society of Radiology
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    • v.15 no.2
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    • pp.173-179
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    • 2021
  • Scattered x-ray generated by digital radiography systems also have the advantage of increasing signals, but ultimately detectability is reduced by decreasing resolution and increasing noise of x-ray images transmitted objects. An indirect method of measuring scattered x-ray in a modulation-transfer function (MTF) for evaluating resolution in a spatial-frequency domain can be considered as a drop in the MTF value corresponding to zero-frequency. In this study, polymethyl methacrylate (PMMA) was used as a patient tissue equivalent, and MTFs were obtained for various thicknesses to quantify the effect of scattered x-ray on resolution. X-ray image signals were observed to decrease by 35 ~ 83% with PMMA thickness increasing, which is determined by the absorption or scattering of x-rays in PMMA, resulting in reduced MTF and increased scatter fraction. The method to compensate for MTF degradation by PMMA resulted in the MTF inflation without considering the optical spreading generated by the indirect-conversion type detector. Data fitting or zero-padding are needed to compensate for MTF more reasonably on edge-spread function or line-spread function.

The history of ginseng cultivation in Orient (동양에 있어서의 인삼재배 역사)

  • Koh, Seungtae
    • Journal of Ginseng Culture
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    • v.1
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    • pp.57-66
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    • 2019
  • Ginseng has been recognized as a lifespan extending medicine which has been regarded as one of the medicines classified as top medicines, as the Boncho (medical herbs) study which is influenced by the idea of guidance's costume and food concept mainly in China is gaining its bona fide form. As the demand for ginseng has been expanded to other levels, the demand for ginseng has been increasing. Ginseng from the nature reached its supply chain limit due to its extinction and difficulty of picking, so it translated into ginseng cultivation of economy rather than harvesting in nature. After the start of ginseng cultivation, the ginseng cultivation was further enhanced by the rapid development of processing methods such as white-ginseng and red-ginseng, and the surge of consumption due to the traditional belief in ginseng drug efficacy and support of scientific research. In the Joseon Dynasty, the name Gasam (cultivated ginseng) had been created as ginseng was cultivated on farmland after the stage of SanYang (wild cultivated ginseng), the purpose of the new name Gasam is to differentiate from natural ginseng, and natural ginseng lost its firm position as the genuine ginseng as the Gasam replaced the genuine ginseng, and the natural ginseng got a new name of SanSam (wild ginseng). Because the real ginseng substance concept dissipated, and as Gasam is being called ginseng, the name Gasam was also disappeared. As a result, it was possible to grow large quantities according to the arrival of the Gasam era, and it was possible to supply the demand for ginseng, and it could become one agricultural industry. In this ginseng cultivation, in Japan where ginseng did not grow naturally, it was difficult to obtain ginseng from Joseon and faced with a shortage of ginseng at all times. Therefore, the shogun cultivated the Gasam systematically at the national level by the inside of the shogunate. However, since the natural ginseng is native to China and Korea, there is a concern about the deterioration of the quality of natural ginseng due to the incorporation of cultivated ginseng (Gasam). To protect the interests, the cultivation of ginseng was subject to control. For this reason, the lack of historical information on Gasam cultivation, which had to be started secretly, would be a natural result. In this paper, althouh not sufficient enough, the historical informations were used to summarize the history of ginseng cultivation in China, Japan and Korea.

Whiplash Injury Conditions of Rear-End Collisions at Low-Speed (저속 추돌사고에서 목 상해 조건에 대한 연구)

  • Kim, Myeongju;Yun, Ilsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.2
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    • pp.58-76
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    • 2019
  • As the number of reported injuries has tended to increase over time, large hospitalization expenditure from excessive medical treatments and hospitalization, and insurance frauds associated with moral hazard in minor collisions have caused a global societal problem. Many occupants of rear-ended vehicles involved in rear-end collisions complain of whiplash injury, which is also known as neck injury, without any anatomical and radiological evidence. With only clinical symptoms, stating that a whiplash injury is a type of injury defined by the Abbreviated Injury Scale would be difficult. Therefore, this study focuses on minor rear-end collisions, where the rear-ender vehicle collides with the rear-ended vehicle at rest. The mathematics dynamic model is employed to simulate a total of 100 rear-end collision scenarios based on various weights and collision speeds and identify how the weights and speeds of both vehicles influence the risk of whiplash injury in occupants involved in minor rear-end collisions. The possibility of an injury is very high when the same-weight vehicles are involved in accidents at collision speeds of 15 km/h or higher. The possibilities are 36% and 84% with collision speeds of 15 km/h and 20 km/h, respectively, if weights are disregarded.

Morphologic Alterations in Amygdala Subregions of Adult Patients with Bipolar Disorder

  • Lee, Hyun-Jae;Han, Kyu-Man;Kim, Aram;Kang, Wooyoung;Kang, Youbin;Kang, June;Won, Eunsoo;Tae, Woo-Suk;Ham, Byung-Joo
    • Korean Journal of Biological Psychiatry
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    • v.26 no.1
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    • pp.22-31
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    • 2019
  • Objectives Previous studies have revealed inconsistent results on amygdala volume in adult bipolar disorder (BD) patients compared to healthy controls (HC). Since the amygdala encompasses multiple subregions, the subtle volume changes in each amygdala nucleus might have not been fully reflected in the measure of the total amygdala volume, causing discrepant results. Thus, we aimed to investigate volume changes in each amygdala subregion and their association with subtypes of BD, lithium use and clinical status of BD. Methods Fifty-five BD patients and 55 HC underwent T1-weighted structural magnetic resonance imaging. We analyzed volumes of the whole amygdala and each amygdala subregion, including the anterior amygdaloid area, cortico-amygdaloid transition area, basal, lateral, accessory basal, central, cortical, medial and paralaminar nuclei using the atlas in the FreeSurfer. The volume difference was analyzed using a one-way analysis of covariance with individual volumes as dependent variables, and age, sex, and total intracranial volume as covariates. Results The volumes of whole right amygdala and subregions including basal nucleus, accessory basal nucleus, anterior amygdaloid area, and cortico-amygdaloid transition area in the right amygdala of BD patients were significantly smaller for the HC group. No significant volume difference between bipolar I disorder and bipolar II disorder was found after the Bonferroni correction. The trend of larger volume in medial nucleus with lithium treatment was not significant after the Bonferroni correction. No significant correlation between illness duration and amygdala volume, and insignificant negative correlation were found between right central nucleus volume and depression severity. Conclusions Significant volume decrements of the whole amygdala, basal nucleus, accessory basal nucleus, anterior amygdaloid area, and cortico-amygdaloid transition area were found in the right hemisphere in adult BD patients, compared to HC group. We postulate that such volume changes are associated with altered functional activity and connectivity of amygdala nuclei in BD.

Comparative Research on Global Policy in ICT Accessibility for Vulnerable Groups -Focusing on Implementation of Legislative System- (취약계층을 위한 정보통신 접근성 정책에 대한 국가 간 비교 연구 -관련제도 중심으로-)

  • Kim, Jung-Yeon;Park, Sung-Woo;Kang, Byung-Gwon;Son, Chang-Yong;Jung, Bong-Keun
    • 재활복지
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    • v.20 no.1
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    • pp.131-150
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    • 2016
  • This study aims to compare global policies on ICT accessibility and to suggest possible solutions that help to enhance ICT accessibility for socially disadvantaged groups. The results indicated that related laws and standards in Korea are relatively well established than Asian countries' whereas they need improvements when compared to the US or the UK. Particularly, in spite of rapid development in information communication technology industry, incorporating the definition of newly developed technologies into existing laws related to ICT accessibility seemed slow that caused reluctancy of related parties to address accessibility issues the new technologies create. In addition, Korean government seems less effortful to develop policies and standards apart from web and mobile application accessibility. In order to resolve the problems, firstly, the period or process of enacting and amending laws can be shorten. Next, a government affiliated research institute can be established to do research and develop ICT accessibility related to user scenarios so that effective policies and standards could be readily provided. Even though other possible solutions can be suggested, what is more important than that is that any interested parties should sustainably make efforts to provide equal opportunities for the underserved populations.

Compatibility Analysis Through the System of Chief, Deputy, Assistant, and Envoy for Socheongnyong-tang (소청룡탕(小靑龍湯)의 군신좌사(君臣佐使) 배오(配伍) 분석)

  • Kim, Do Hoy;Yoon, Michung;Shin, Soon Shik
    • Herbal Formula Science
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    • v.26 no.4
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    • pp.363-380
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    • 2018
  • Objectives : We analyzed the principle of compatibility of socheongnyong-tang and expanded the range of application in clinical practice. Methods : Socheongnyong-tang was analyzed by the compatibility principle through the system of chief, deputy, assistant, and envoy, but the basic formulas of "Discussion of Cold Damage" and "Synopsis of the Golden Chamber" was used. Results : Socheongnyong-tang treats exterior wind-cold and interior water accumulation. Exterior wind-cold is treated mainly by exterior-releasing herbs constituting mahwang-tang and gyeji-tang in "Discussion of Cold Damage", and interior water accumulation is treated mainly by retained fluid-resolving herbs constituting yeonggamomigangsinha-tang, yeonggamomigagangsinbanhahaengin-tang and yeonggamomigagangsinbanhaengdaehwang-tang in "Synopsis of the Golden Chamber". Depending on the weight of exterior wind-cold and interior water accumulation, the disease condition is classified as a case where exterior wind-cold is heavier than interior water accumulation, a case where exterior wind-cold is lighter than interior water accumulation, and a case where it is equivalent. When exterior wind-cold is heavier than interior water accumulation, chief herbs are Ephedrae Herba and Cinnamomi Ramulus of exterior-releasing herbs series and deputy herbs are Zingiberis Rhizoma and Asari Radix et Rhizoma of retained fluid-resolving herbs series. When exterior wind-cold is equal to the disease condition of interior water accumulation, chief herbs are Ephedrae Herba of exterior-releasing herbs series and Zingiberis Rhizoma of retained fluid-resolving herbs series, and deputy herbs are Cinnamomi Ramulus of the exterior-releasing herbs series and Asari Radix et Rhizoma of retained fluid-resolving herbs series. When exterior wind-cold is lighter than interior water accumulation, chief herbs are Zingiberis Rhizoma and Asari Radix et Rhizoma of retained fluid-resolving herbs series and deputy herbs are Ephedrae Herba and Cinnamomi Ramulus of exterior-releasing herbs series. In any case, assistant herbs are Pinelliae Rhizoma, Paeoniae Radix alba, and Schisandrae Fructus, and envoy herb is Glycyrrhizae Radix preparata. Conclusions : In conclusion, socheongnyong-tang must differently formulate the system of chief, deputy, assistant, and envoy according to the grade of exterior wind-cold and interior water accumulation. These results suggest that socheongnyong-tang can be applied flexibly when applied in clinical practice to enhance the therapeutic effect.

A Secure and Lightweight Authentication Scheme for Ambient Assisted Living Systems (전천 후 생활보조 시스템을 위한 안전하고 경량화 된 인증기법)

  • Yi, Myung-Kyu;Choi, Hyunchul;Whangbo, Taeg-Keun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.4
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    • pp.77-83
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    • 2019
  • With the increase in population, the number of such senior citizens is increasing day by day. These senior citizens have a variety of care needs, but there are not enough health workers to look after them. Ambient Assisted Living (AAL) aims at ensuring the safety and health quality of the older adults and extending the number of years the senior citizens can live independently in an environment of their own preference. AAL provides a system comprising of smart devices, medical sensors, wireless networks, computer and software applications for healthcare monitoring. AAL can be used for various purposes like preventing, curing, and improving wellness and health conditions of older adults. While information security and privacy are critical to providing assurance that users of AAL systems are protected, few studies take into account this feature. In this paper, we propose a secure and lightweight authentication scheme for the AAL systems. The proposed authentication scheme not only supports several important security requirements needed by the AAL systems, but can also withstand various types of attacks. Also, the security analysis results are presented to show the proposed authentication scheme is more secure and efficient rather than existing authentication schemes.

Understanding and Prevention of Fall-related Injuries in Older Adults in South Korea: A Systematic Review (한국 노인의 넘어짐과 연계된 인체손상에 대한 이해와 예방: 체계적 문헌 고찰)

  • Lim, Ki-taek;Lee, Ji-eun;Park, Ha-eun;Park, Su-young;Choi, Woochol Joseph
    • Physical Therapy Korea
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    • v.26 no.2
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    • pp.34-48
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    • 2019
  • Background: Fall-related injuries in older adults are a major health problem, and the risks and mechanisms of these injuries should be affected by race, culture, living environment, and/or economic status. Objects: Research articles have been systematically reviewed to understand fall-related injuries in older adults in South Korea. Methods: 128 published research papers have been found through the Korea Citation Index and the Korean Studies Information Service System, and reviewed in various perspectives, including incidents, fall death rates, medical costs, causes, injury sites and types, locations where falls occurred, prevention strategies, scholarly fields interested in fall injuries, and the role of physical therapy. Results: Fall-related injuries were found to be more common in women than in men, and the number of incidents increased with age, with the highest rate found in individuals over 85 years old. Risk of fall injury was associated with education level, comorbidities, and fear of falling. Common places where falls occurred included the bathroom, living room, stairs, and hallway. Common types of injury included bruises, fractures, and sprains in the lower extremities. Intervention strategies included exercise programs, education, and protective clothing. Scholarly fields interested in fall-related injuries in older adults included medicine, nursing, physical therapy, occupational therapy, physical education, pharmacology, oriental medicine, biomedical engineering, design, clothing, and textiles. Physical therapy intervention using proprioceptive neuromuscular facilitation has been used to improve one's balance. Conclusion: Any movement during the activities of daily living can lead to a fall. Physical therapists are highly educated to analyze human movements and should be involved in more research and practices to solve fall-related injuries in older adults.

A Clinical Study on the Pattern-Specific Cut-Point for the Pattern Identification Diagnostic Tool for Climacteric and Postmenopausal Syndrome (갱년기장애 및 폐경기증후군 변증진단 도구의 진단결과 도출을 위한 변증별 절단점 연구)

  • Lee, In-Seon;Kim, Jong-Won;Jeon, Soo-Hyung;Chi, Gyoo-Yong;Kang, Chang-Wan
    • The Journal of Korean Obstetrics and Gynecology
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    • v.32 no.2
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    • pp.29-49
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    • 2019
  • Objectives: This study was a methodological study to verify the reliability and validity and to make a diagnosis of a diagnostic tool for climacteric and postmenopausal syndrome pattern identification (CaPSPI). Methods: This study was conducted from June 1, 2018 to October 18, 2018 with ${{\bigcirc}{\bigcirc}}$ University Korean Medicine Hospital IRB's approval (2018-3). To make a diagnosis using CaPSPI, we decided the cut-points for the tool. Three professors of ${{\bigcirc}{\bigcirc}}$Korean Medical University conducted pattern identification diagnosis. The result is marked from 0 to 3, 0 is 'No', 1 is 'Slightly Yes', 2 is 'Yes' and 3 is 'Very Yes'. And if two or more professors' diagnoses are the same, we took the diagnoses as a diagnostic criteria. The decision of pattern by three experts converted to 0-1 scores in two ways. In "method 1", if the diagnosis was zero points, the score was 0 (have no such identification), and the rest was 1 (have such identification). In "method 2", if the diagnosis was zero or 1 point, the score was 0, and the rest was 1. After that, intraclass correlation was calculated for experts agreement. And logistic regression was conducted. A response variable was the results of the experts' diagnosis and an explanatory variable was the results of the pattern identification diagnostic tool. Results: The diagnosis of the three experts showed excellent concordance of more than 0.794 and showed a significant correlation with the diagnostic tool. Both 'Method 1' and 'Method 2' showed statistically significant effects with the diagnosis of 3 experts and the results of the diagnostic tool. The frequency of cumulative pattern identification diagnosis in 'Method 1' and 'Method 2' were found to be 578 occasions and 203 occasions, respectively. The average number of pattern held by participants in 'Method 1' and 'Method 2' were found to be 5.26 and 1.85, respectively. In both "Method 1" and "Method 2," the yield frequency of liver qi depression was the highest, and the frequency of kidney yin deficiency and liver-kidney yin deficiency was relatively high. Conclusions: Based on the above results, it is thought that, in diagnosis using CaPSPI of menopausal women, 'method 1' could be used for the health diagnosis and prevention, 'method 2' could be used for the pattern diagnosis. On the conclusion, CaPSPI is thought to be available for pattern diagnosis of menopause women.

Gintonin-mediated release of astrocytic vascular endothelial growth factor protects cortical astrocytes from hypoxia-induced cell damages

  • Choi, Sun-Hye;Kim, Hyeon-Joong;Cho, Hee-Jung;Park, Sang-Deuk;Lee, Na-Eun;Hwang, Sung-Hee;Rhim, Hyewon;Kim, Hyoung-Chun;Cho, Ik-Hyun;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.43 no.2
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    • pp.305-311
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    • 2019
  • Background: Gintonin is a ginseng-derived exogenous ligand of the G protein-coupled lysophosphatidic acid (LPA) receptor. We previously reported that gintonin stimulates gliotransmitter release in primary cortical astrocytes. Astrocytes play key roles in the functions of neurovascular systems. Although vascular endothelial growth factor (VEGF) is known to influence the normal growth and maintenance of cranial blood vessels and the nervous system, there is little information about the effect of gintonin on VEGF regulation in primary astrocytes, under normal and hypoxic conditions. Methods: Using primary cortical astrocytes of mice, the effects of gintonin on the release, expression, and distribution of VEGF were examined. We further investigated whether the gintonin-mediated VEGF release protects astrocytes from hypoxia. Results: Gintonin administration stimulated the release and expression of VEGF from astrocytes in a concentration- and time-dependent manner. The gintonin-mediated increase in the release of VEGF was inhibited by the LPA1/3 receptor antagonist, Ki16425; phospholipase C inhibitor, U73122; inositol 1,4,5- triphosphate receptor antagonist, 2-APB; and intracellular $Ca^{2+}$ chelator, BAPTA. Hypoxia further stimulated astrocytic VEGF release. Gintonin treatment stimulated additional VEGF release and restored cell viability that had decreased due to hypoxia, via the VEGF receptor pathway. Altogether, the regulation of VEGF release and expression and astrocytic protection mediated by gintonin under hypoxia are achieved via the LPA receptor-VEGF signaling pathways. Conclusion: The present study shows that the gintonin-mediated regulation of VEGF in cortical astrocytes might be neuroprotective against hypoxic insults and could explain the molecular basis of the beneficial effects of ginseng on the central nervous system.