알긴산나트륨 기반 100% 자연분해 음식물 쓰레기봉투 개발

이우석,이태규,김재현 한국공업화학회 2022 한국공업화학회 연구논문 초록집 Vol.2022 No.1

상안검에 국한되어 발생한 Merkel 세포 종양 1예

이우석,김상원,노주헌.Woo Seok Lee. MD. Sang Won Kim. MD. Joo Heon Roh. MD. PhD 대한안과학회 2012 대한안과학회지 Vol.53 No.6

Purpose: To report a case of Merkel cell carcinoma on the left upper eyelid without metastasis and its immunohistochemical features. The carcinoma was successfully treated with excisional surgery and prophylactic radiation therapy. Case summary: A 76-year-old woman presented to the hospital complaining of a 0.6 × 0.9-cm-sized painless and purplish- red colored mass that had grown rapidly on her left upper eyelid margin over the previous two months. An excisional biopsy was performed. On immunohistochemical examination of the lesion, the tumor cells expressed immunoreactivity for synaptophysin and were negative for LAC and cytokeratin, confirming the diagnosis of Merkel cell carcinoma. Additional surgery was performed because the surgical margins were positive. No other primary or metastatic lesions were found. The patient was treated with local prophylactic irradiation and remained disease-free at her 10-month follow-up visit. J Korean Ophthalmol Soc 2012;53(6):856-860

[논문]결정화 유리첨가에 의한 BNT 계 세라믹 복합체의 소결 및 유전특성

이우석,이병철,류봉기 釜山大學校生産技術硏究所 2003 生産技術硏究所論文集 Vol.62 No.-

본 연구에서는 BaO-Nd2O3-TiO2계 마이크로파 유전체 세라믹스에 결정화 유리를 첨가하여 적충일체형 RF 수동소자 모률 구현을 위한 저온소결 유전체소재를 개발하고자 하였다. BaO-Nd2O3-TiO2에 결정화 유리를 5~3Owt% 범위로 첨가하여 소결온도를 1300°C 에서 1050 °C 로 낮추었으며, 첨가량의 증가에 따라서 소결밀도의 증가 및 입성장이 뚜렸이 일어났고 결정화 유리를 20wt% 첨가하여 1050 °C의 소결온도에서 95% 이상의 상대밀도를 갖는 소결체를 얻을 수 있었다. 이때 유전율(Er),72,품질계수(Q . f),1500, 공진주파수 온도계수(tf), 22 ppm/°C 을 나타내었으며 이는 LTCC 재료로서 응용가능성이 있다고 판단되었다.

殺鼠劑 中毒의 臨床的 考察

李愚奭 우석대학교 의과대학 1971 우석의대잡지 Vol.8 No.1

Improvement of CH selection of WSN Protocol

이우석,정계동,이종용 한국인터넷방송통신학회 2017 Journal of Advanced Smart Convergence Vol.6 No.3

A WSN (Wireless Sensor Network) is a network that is composed of wireless sensor nodes. There is no restriction on the place where it can be installed because it is composed wirelessly. Instead, sensor nodes have limited energy. Therefore, to use the network for a long time, energy consumption should be minimized. Several protocols have been proposed to minimize energy consumption, and the typical protocol is the LEACH protocol. The LEACH protocol is a cluster-based protocol that minimizes energy consumption by dividing the sensor field into clusters. Depending on how you organize the clusters of sensor field, network lifetimes may increase or decrease. In this paper, we will improve the network lifetime by improving the cluster head selection method in LEACH Protocol

식품 접촉 모사 환경에서 식품유사용매의 LDPE-나노 TiO₂ 복합필름 재질특성 영향 평가

이우석,최재천,박세종,김미경,고성혁,Lee, Wooseok,Choi, Jae Chun,Park, Se-jong,Kim, MeeKyung,Ko, Seonghyuk 한국포장학회 2017 한국포장학회지 Vol.23 No.3

The effect of food simulants on properties and light barrier function of LDPE-nano $TiO_2$ composite film has been investigated. LDPE-nano $TiO_2$ composite films were prepared with 5.0wt% $TiO_2$ content by melt-extrusion. To simulate food contact environment, according to KFDA standards and specifications for food utensils, containers and packages, food simulants were selected with deionized water, 50% ethanol, 4% acetic acid and n-heptane and composite films were immersed in each food simulant at $70^{\circ}C$, 30 min except n-heptane ($25^{\circ}C$, 60 min). A variety of material properties, including crystallinity, chemical bonds, surface morphology, mechanical, oxygen barrier and optical properties, of LDPE-nano $TiO_2$ composite film were examined with and without the food simulants treatment. As a result, under regulated migration condition, LDPE-nano $TiO_2$ composite showed extremely stable in all properties tested in the study in contact with food simulants indicating that $TiO_2$ nanoparticles are physicochemically stable and quite compatible with LDPE. Results enable us to anticipate migration of $TiO_2$ will probably not occur. To evaluate influence of migration of $TiO_2$ on food stuffs, their color, pH and acidity were observed as well.

Improving Hot Spot Problem in Layer of DL-LEACH

이우석,진승연,정계동,이종용 한국인터넷방송통신학회 2017 International Journal of Internet, Broadcasting an Vol.9 No.2

The abstract should summarize the contents of the paper and written below the author information. Use th In Wide-area Wireless Sensor Networks, network lifetime is short due to energy consumption due to transmission distance. To improve this, we divide the sensor field into layers and reduce transmission distance through multi-hop transmission. However, there is a problem in that the transmission rate drops because there is no Cluster Head in the layer, or the transmission distance increases due to the layer, and energy is wasted. There are DL-LEACH and EDL-LEACH as Protocols to improve this. DL-LEACH uses either single-hop transmission or multi-hop transmission depending on the situation. As a result, the transmission distance is optimized, thereby reducing energy consumption. In case of EDL-LEACH, it is proposed to improve the data rate in DL-LEACH. It is the same as DL-LEACH, but the Cluster Head is mandatory for all layers to improve the transmission rate. Although there is no Cluster Head for each layer, the transmission rate is improved, but the network life is shortened. In this paper, we try to improve the network lifetime while maintaining the EDL-LEACH transmission rate. The shortened network lifetime is due to Cluster Head overload near the base station. To improve this, the Cluster Head distribution method is improved and the network lifetime is improved.

The Improved Efficiency Network Life-time in TEEN

이우석,이성로,이종용 한국인터넷방송통신학회 2016 Journal of Advanced Smart Convergence Vol.5 No.1

In this paper, we’re compared network protocol which is network lifetime longer when using LEACH Protocol, SEP, and TEEN in a heterogeneous Wireless Sensor Network with a Large Sensor Area. Also, we propose a method of divided layer the wide-area sensor filed and transmitting a multi-hop to improve the network lifetime. And we’re compared network protocol which is network lifetime more improved apply the proposed method to LEACH Protocol, SEP, and TEEN. We tried to compare results, TEEN showed the best network lifetime. Apply the proposed method to divided the sensor field, L-TEEN (Layered TEEN)’s network lifetime rates of improvement is highest.

Enhance Charge Cycle Efficiency of Lead-acid Battery using Solar Power System

이우석,박한밀,신은수 적정기술학회 2018 적정기술학회지(Journal of Appropriate Technology) Vol.4 No.2

In developing countries, many areas are not supplied with electricity due to lack of electric power infrastructure, and many others are suffering from unstable power quality and frequent power outages. As an alternative, power supply using renewable energy, such as solar, wind, and small hydro power, is being activated. Among these, the most widely used source is photovoltaic power generation system, which is easy to install and maintain. In developed countries where power supply is smooth, grid connected photovoltaic systems that use conventional electricity together are generally used for the purpose of reducing electricity bill. However, in developing countries, because conventional electricity supply is unstable, independent solar power generation systems using batteries are mainly used. Among these, a solar panel is a semi-permanent product that can be used for more than 20 years, whereas a typical battery is a consumable with a maximum life span of less than five years, accounting for most maintenance cost of solar power systems. In addition, in the case of a lead storage cell, which is readily available in developing countries and therefore is most widely used, lifespan has been drastically reduced depending on environmental conditions such as pre-charge method, temperature, and humidity, which frequently makes it replaced in six months. For these reasons, management methods to extend lifespan of lead storage cell have become an important research topic. In this study, a voltage level was set as a measure value to identify and manage the characteristics of charging and discharging of lead storage batteries, and standardized discharge curves were created using LED lamps that consume the most stable power. Based on this, the discharging characteristics for different kinds of DC and AC products were identified. Also, the proper isolation voltage level to extend the battery lifespan was verified. The study will be used to design an optimized solar power system along with the further study on charging efficiency of solar power systems in developing countries.

A Study on Science Experimental Serious Game based on the Elementary and Middle School Curriculum : Focused on the Newton’s Laws of Motion

이우석,오규환 (사)한국컴퓨터게임학회 2019 한국컴퓨터게임학회논문지 Vol.32 No.2

Smart education, a perspective which combines suitable data and technologies with the learning experience, is an important objective of Korean education. A key consideration of science education content for smart education is to create self-directed and engaging content tailored to the user based on their level and aptitude. Within science education, which relies on experimentation to teach concepts and theory, smart education content should include aspects allowing users to experiment and learn on their own. The present research aims to develop such smart education content, which meets the goals of the elementary and middle school science curricula. Newton's laws of motion was selected as the education topic, as they are the basis for physics education curriculum at the elementary and middle school level. In a traditional science classroom, a single teacher must consider and compensate for the many constraints to the experiment such as time, location, cost, safety from accidents, as well as aim to ensure that the large number of students receive equal learning opportunities. Through teaching Newton's laws of motion through a developed serious game—which satisfies early-level physics curriculum—the present research demonstrates the possibilities of experimental science education content in the era of actual smart education field.