• 공업화학
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• 제27권2호
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• pp.115-122
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• 2016

사람의 머리카락, 눈, 피부 등에서 발견되는 멜라닌은 자연의 생물체에 존재하는 어두운 색소를 가르치는 통칭이다. 멜라닌은 자유 라디컬을 흡수해서 제거하는 특성을 가지고 있어, 해로운 UV 광선이 생체로 침투할 때, 세포 및 조직을 보호하는 역할을 한다. 또한, 전기적 전도성 및 이온 전도성을 가지고 있으며, 항산화성, 젖은 상태에서의 접착성, 금속이온 킬레이팅 등 다기능성으로 인해, 다양한 분야에서의 응용이 주목받고 있다. 자연계에 존재하는 생체 멜라닌의 구조를 정확하게 정의할 수는 없지만, 멜라닌의 응용 분야는 센서, 의료기기 등으로 확대되고 있다. 본 미니총설에서는 멜라닌의 원천과 합성, 구조와 특성, 그리고 다양한 분야로의 응용 가능성에 대해서 구체적으로 논의한다.

• International Journal of Industrial Entomology and Biomaterials
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• 제35권2호
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• pp.83-88
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• 2017

Silk is appealing materials for many biomedical applications involving tissue engineering and implantable devices, because of its biocompatibility, environmental stability, controlled proteolytic biodegradability and morphologic flexibility. Silk matrix is required for the treatment of a wide wound area, but the present silk matrix is made by the second processing, and thus, the labor and the cost are high. In this work, we investigated the optimal production condition of natural silk 3D matrix using the silkworms and invented Automatic Silk Matrix Making Machine (ASMMM) for natural silk 3D matrix production. As a result, we determined that optimal production condition for making A4 paper size natural silk 3D matrix was used Rough aquarelle paper on surface at $25^{\circ}C$ and 30 silkworm larvae. These results are expected to provide basic data for the efficient production of the natural silk 3D matrix, and it is suggested that the produced natural silk 3D matrix is useful as a medical biomaterials.

• 한국멀티미디어학회논문지
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• 제22권2호
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• pp.242-249
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• 2019

Old people and patients with cardiovascular disease could die of a heart attack in the bath with heated water for a long time. Various researches have been studied to prevent these accidents from happening such as measuring the ECG signal when taking bath. However, these devices are hard to use and the higher price is not easily accepted by the public. In this paper, a low-cost and use-friendly, real time high precision water temperature monitoring device to prevent heart attack in the bath was developed. The device with waterproof design that lets the device can float on the surface of the water, and an accurate way to make water temperature measurement method was proposed by this paper that is immerging the sensor into water with 4cm depth to measure the temperature of underwater. The manufactured device was conducted to two experiments; one was to verify the basic functions of the device, and another one was for compare the proposed device with commercial products for monitoring the water temperature in the bathtub. As the experimental results shown, the proposed device has stable performance for the water temperature measurement and communicating with laptop in wireless.

• 대한의용생체공학회:의공학회지
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• 제40권2호
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• pp.55-61
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• 2019

Recently, various researches on materials and equipment have been actively conducted to overcome the limitations of conventional output methods due to the increase of diversity of 3D printing materials and to adopt an output method suitable for the characteristics of each material. As the range applicable to outputable materials is expanded, manufacturing of medical devices applied to patients is in a more rapid growth trend than other fields. In this study, we investigated the suitable materials for fabricating 3D printer using photocurable resin. As a result, one suitable material was selected through biological safety experiment and thermal stability experiment. Next, to optimize the output of the selected materials, we have developed a system that optimizes the equipment according to the characteristics of the material. The results of this study enabled the implementation of personalized medical implants that could not be made from 3D printer dependent materials, thereby overcoming the limitations of existing 3D printer output conditions and dedicated materials.

• Integrative Medicine Research
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• 제6권3호
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• pp.254-259
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• 2017

Background: Those classified as Tae-Eum (TE)-type people in Sasang constitutional medicine (SCM) are prone to obesity. Although extensive clinical observations have confirmed this tendency, the underlying physiological mechanisms are unknown. Here, we propose a novel hypothesis using integrative physiology to explain this phenomenon. Methods: Hypoactive lung function in the TE type indicates that respiration is attenuated at the cellular level - specifically, mitochondrial oxygen consumption. Because a functional reduction in cellular energy metabolism is suggestive of intrinsic hypoactivity in the consumption (or production) of metabolic energy, we reasoned that this tendency can readily cause weight gain via an increase in anabolism. Thus, this relationship can be derived from the graph of cellular metabolic power plotted against body weight. We analyzed the clinical data of 548 individuals to test this hypothesis. Results: The statistical analysis revealed that the cellular metabolic rate was lower in TEtype individuals and that their percentage of obesity (body mass index >25) was significantly higher compared to other constitutional groups. Conclusion: Lower cellular metabolic power can be an explanation for the obesity trend in TE type people.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2021년도 제63차 동계학술대회논문집 29권1호
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• pp.45-46
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• 2021

의료영상이란 의료영상장비로부터 DICOM이라는 의료영상표준에 따라 저장되며, 의료영상관리 시스템인 PACS를 통해 관리된다. 이러한, 의료영상장비 ICT기술이 융합되어 급격하게 발전되고 있으며 다양한 의료영상장치가 개발되어지고 있다. 하지만, 기술력은 높아지고 있으나 개발된 의료영상장비로부터 촬영된 영상품질관리에 대한 문제점이 제기되고 있다. 이와 관련하여 다기관의 의료영상장비 개발과 해당 기기로부터 수집된 의료영상에 대한 품질을 관리할 필요성이 증가하고 있다. 따라서 코로나 19와 같은 상황에서 의료기기 개발 지원과 관리를 비대면 관리서비스 시스템 개발과 의료영상장치 개발 정도를 관리할 수 있을 뿐만 아니라 의료영상에 대한 품질까지 모니터링하여 및 개선 할 수 있는 시스템을 제안하고자 한다.

• 반도체디스플레이기술학회지
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• 제22권3호
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• pp.101-105
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• 2023

Organic photo Diodes (OPDi) give multiple advantages in the growing interest of the flexible optoelectronic devices. Organic semiconductors are freeform as they can deposit on any substrate, so it could be flexible. But the inorganic material photodiodes (PDs) are usually fabricated on silicon wafers which are solid. So, normally PDs are inflexible. By those reasons, we decided to make the vacuum deposited small molecule OPDi. We have investigated the OPDi's J-V characteristic by changing the thickness of p-type layer of OPDi. This device consists of indium-tin-oxide (ITO) / 2,3:6,7-dibenzanthracene (pentacene) / buckminsterfullerene (C60) / aluminum (Al). Its J-V characteristics were measured in the probe station(4156C) that can give dark condition while measuring. And for the luminance characteristics, the photocurrent was measured with the bright halogen lamp and a probe station.

• 대한의용생체공학회:의공학회지
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• 제38권4호
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• pp.143-152
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• 2017

The main purpose of this research was to examine the EMG characteristics of driver's upper limb and driving performance for operating accelerator and brake pedal by using four types of left hand control devices(Push/Pull, Push/Right angle, Push/Rock, Push/Twist) during simulated driving. The persons with disabilities in the lower extremity have problems in operation of the vehicle because of functional impairments for controlling accelerator and brake pedal. Therefore, if hand control device is used for adaptive driving controls in persons with lower extremity loss, the disabled people could improve their quality of mobility life by driving a car. Twenty subjects were involved in this research to assess driving performance and EMG activities for operating accelerator and brake pedal by using four types of left hand controls in driving simulator. We measured EMG responses of six muscles(posterior deltoid, middle deltoid, biceps, triceps, extensor carpi radialis, and flexor carpi radialis) during pulling and pushing movement with four types of left hand controls for acceleration and braking. STISim Drive 3 program was used for evaluation test of four types of left hand control devices in straight lane course for time to reach target speed and brake reaction time. While operating the four types of left hand controls for acceleration, EMG activities of posterior deltoid in normal subjects were significantly increased(p < 0.05) compared to the disabled subjects. It was also found that EMG responses of triceps and posterior deltoid were significantly increased(p < 0.05) when using the Push/Right angle type than Push/Pull type. While operating the four types of left hand controls for braking, EMG activities of flexor carpi radialis and triceps in subjects with disability were significantly increased(p < 0.05) compared to the normal subjects. It was shown that muscle responses of posterior deltoid, middle deltoid and triceps were significantly increased when using the Push/Right angle type than Push/Rock type. Time to reach target speed and brake reaction time in subjects with disability was increased by 2.5% and 4.6% on average compared to normal subjects. The person with disabilities showed a tendency to relatively slow performance in acceleration at the straight lane course.

• 대한의용생체공학회:의공학회지
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• 제38권2호
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• pp.74-81
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• 2017

The purpose of this study was to investigate the EMG characteristics of driver's upper extremity and driving performance for manipulating brake and accelerator pedal by using left and right hand control devices during simulated driving. The people with disabilities in the lower limb have problems in operation of the motor vehicle because of functional loss for manipulating brake and accelerator pedal. Therefore, if hand control device is used for adaptive driving controls in people with lower limb impairments, the disabled people can improve their quality of life by driving a motor vehicle. Six subjects were participated in this study to evaluate driving performance and muscle activities for operating brake and accelerator pedal by using two different hand controls (steering column mounted hand control and floor mounted hand control) in driving simulator. We measured EMG activities of six muscles (posterior deltoid, middle deltoid, triceps, biceps, flexor carpi radialis, and extensor carpi radialis) during pushing and pulling movement with different hand controls for acceleration and braking. STISim Drive 3 software was used for the performance test of different hand control devices in straight lane course for time to reach target speed and brake reaction time. While pulling the hand control lever toward the driver, normalized EMG activities of middle deltoid, triceps and flexor carpi radialis in subjects with disabilities were significantly increased (p < 0.05) compared to the normal subjects. It was also found that muscle responses of posterior deltoid were significantly increased (p < 0.05) when using the right hand control than left hand control. While pushing the hand control lever forward away from the driver, normalized EMG activities of posterior deltoid, middle deltoid and extensor carpi radialis in subjects with disability were significantly increased (p < 0.05) compared to the normal subjects. It was shown that muscle responses of middle deltoid, biceps and extensor carpi radialis were significantly increased when using the right hand control than left hand control. Brake reaction time and time to reach target speed in subjects with disability was increased by 12% and 11.3% on average compared to normal subjects. The subjects with physical disabilities showed a tendency to relatively slow acceleration at the straight lane course.

• 한국음향학회지
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• 제39권4호
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• pp.303-317
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• 2020

체외충격파치료술(Extracorporeal Shock Wave Therapy, ESWT)은 보존적인 치료가 어려운 근골격계 난치성 통증 치료 뿐 아니라 심혈관계 질환까지 적용 분야가 확대되고 있는 혁신적인 치료술이다. 본 연구에서는 국내에서 사용되는 집속형 ESWT 치료기의 성능을 결정하는 충격파 음향 출력의 분포를 조사했다. 분석에 사용된 데이터는 식약처에 등록된 30개 기술 문서를 통해 수집했다. 조사 결과, ESWT 치료기 충격파의 집속 특성은, 초점 거리가 5 mm ~ 65 mm, 초점 폭이 3 mm ~ 30 mm, 초점 깊이가 4 mm ~ 108 mm 범위에서 변화하고 있다. 충격파의 최대 양압(P+)는 7 MPa ~ 280 MPa, 초점에서 에너지 밀도 Energy Flux Density(EFD)는 0.0035 mJ/㎟ ~ 35 mJ/㎟, 펄스당 에너지(E)는 0.737 mJ ~ 80.86 mJ로 매우 넓은 범위에서 분포하고 있다. P+ 및 EFD 상관성 분석에 포함된 모든 국내산 PE 방식 제품(5개) 및 1개의 EM 방식 국산 치료기는 P+ 및 EFD가 통상적인 범위를 크게 벗어나고 있으며, 예상되는 상관성을 따르지 않고 있어, 데이터의 신뢰성을 인정하기 어려운 상태이다. 음향 출력의 값에 신뢰성을 부여하기 어려운 경우, 식약처에서 인정하는 시험 검사 기관을 통해 사후 시험 검사 및 관리가 요구된다. 충격파 음향 출력에 대한 통과 기준이 치료기의 적응증에 대한 임상 시험 결과를 근거로 설정될 수 있도록 식약처의 규정 및 가이드라인 개선이 필요하다.