렉테나 설계를 위한 이중대역 정합회로 설계

박명윤,최진형,조승호,이원준,한상민 순천향대학교 부설 산업기술연구소 2021 순천향 산업기술연구소논문집 Vol.27 No.2

Wireless Power Transfer(WPT) is very popular because it can wirelessly supply energy to the sensor. The Dual-Band rectenna with ISM matching(2.4-2.48GHz/5.72-5.82GHz) is presented. The dual-band rectenna system consists of harmonics rejection filter, dual-band impedance matching circuit, voltage multiplier rectifier. Especially, for system efficiency, it is important to perform dual-band matching to transfer maximum power to the rectifier. Dual-Band Rectenna can harvest more power than single-band rectenna and be high performance in communication environment using ISM band such as Wi-Fi, Bluetooth existing several-tone signal.

돼지 신장세포(PK15)의 이종이식 거부반응에 대한 재조합 IL-18의 영향

최연실,김은미,김영관,박상연,심정현,윤도영,강형식,명평근 충남대학교 생물공학연구소 2004 생물공학연구지 Vol.10 No.1

Various cytokines including IL-1β, IL-2, IL-4, IL-10, IL-12p40, IFN-γ, and TNF-α have been recently reported to play important roles in both host and donor cell activations during xenotransplantation. Interleukin (IL)-18, a proinflammatory cytokine, can induce IL-4 and IL-13 production in T cells, NK cells, B cells, mast cells, and basophils. IL-18 has the capacity to stimulate innate immunity and both Th1-and Th2- mediated responses, but little is known to involve in the xenograft rejection. In order to investigate the role of IL-18 in xenograft rejection, we transplanted the pig kidney (PK15) cells to C57BL/6 mouse with or without intraperitoneal injection of mouse recombinatant IL-18. It was analyzed the population of T cell, B cell and NK cell in the mice transplanted with PK 15 cells and recombinant IL-18 by flow cytometry. We found that splenic CD3+ T cells were increased in mice injected PK15 cells with recombinant IL-18. These results suggest that recombinant IL-18 is critical in the xenograft rejection by increasing T cell population of the recipients.

석탄회 펠렛의 미연탄소 연소 현상 분석

崔尙丁,李孝眞,吳明淑 弘益大學校 科學技術硏究所 2001 科學技術硏究論文集 Vol.12 No.-

As the number of coal fired power plants in the domestic power industry continues to increases, the amount of fly ash produced is also increasing, making the reutilization of fly ash a vital issue. Various methods to reutilize the fly ash from coal power plants have been investigated, and one of such areas with the potential to grow is the usage as light weight sintered construction materials. Sintered fly ash aggregates are produced in two steps; the first is the pellet formation step, during which the fly ash particles containing unburnt carbons were made into a pellet using caking components, and the second the pellet sintering by the combustion heat of the carbons. During the sintering process, the combustion rate of the carbon affects the characteristics of sintered pellets. The combustion of carbon occurs via adsorption of O₂ on the active sites, and desorption of CO/CO₂. The parameters which affect the rate of adsorption, desorption, and transfer of O₂ and CO/CO₂ include the O₂ partial pressure and flow rate, the pellet size, the porosity, the pore tortuosity, the pore size distribution, the carbon content and distribution. This study investigated the combustion of carbon during the production of sintered fly ash through modeling. A simple combustion model using Langmuir isotherm is used to calculate the pellet temperature. The oxygen diffusion through the pores is ignored. At the temperatures of sintering, the desoption process is a rate limiting process, making the overall rate sensitive to the desoption kinetic parameters. In addition, it was found that the carbon content and the heat capacity of the pellet affected both the rate of the reaction and the final pellet temperature, while the area of active sites only affect the reaction rate. The future work will include the combustion modeling with external and internal diffusion of O₂, and the model confirmation through experimentation.

급속응고된 Al-Zr 합금의 시효현상에 미치는 Si첨가의 영향

최상욱,박홍일,김명호 울산대학교 1987 연구논문집 Vol.18 No.2

본 연구에서는 급속응고된 Al-Zr 합금의 과포화 고용도에 미치는 제3첨가 원소 Si의 영향 및 급속응고된 Al-Zr-Si 합금계의 시효특성에 관하여 실험적으로 조사하였다. Twin-roller 장치에 의하여 급속응고시킨 시편의 응고속도는 10?? K/s 정도였으며, 이때 Al기지내에 Zr은 약 1 wt.% 정도만이 과포화 고용되었다. 그러나 Si의 첨가량이 증가됨에 따라 Zr의 과포화 고용도는 증대되어 Si의 첨가량이 1 wt.% 일때 Zr은 1.7 wt.% 정도 Al기지내에 완전 과포화 고용되었다. 그리고 Si의 첨가량이 증가됨에 따라 Al-Zr 합금의 미소경도는 증대되었다. Al -1.7wt.%Zr -1.0wt.%Si 합금을 시효처리하면 Si이 우선 미세한 구상석출물을 형성하며 초기 시효경화를 일으킨 후, 잇따라 Zr의 준안정 석출물이 불연속 석출되어 성장하며 최대 시효경화를 나타냄을 알 수 있었다. An experimental investigation has been made about the effects of the third alloying element silicon on the sold solubility of zirconium in the aluminium, and on the ageing phenomena of Al-Zr-Si alloys. Rapidly solidified specimens were prepared by a twin-roller quenching apparatus in the form of long, thin ribbon, whose cooling rate was estimated to be about 10?? K/s. Under such a cooling rate, the maximum solubility of zirconium in solid aluminum was extended to about 1.0wt.%. However, it was extended up to 1.7wt.% by addition of 1.0wt.% silicon. With the increase of silicon content, the microhardness of Al-Zr alloys were increased as well. Ageing of supersaturated Al-1.7wt.% Zr-1.0wt.% Si solid solution appeared to occur in three sequential stages; Ⅰ. precipitation of silicon as fine spherical particles which harden the alloys, followed by Ⅱ. discontinuous precipitation of metastable zirconium phases which produce remarkable age hardening of the alloys, and finally Ⅲ. formation of coarse equilibrium zirconium phases.

도시주민의 B형 간염에 대한 예방적 건강행위 이행에 관한 연구

崔翔旭,李明淑,廉容泰 고려대학교 의과대학 1990 고려대 의대 잡지 Vol.27 No.3

Hepatitis B infection is one of the most prevalent epidemic diseases in Korea. As a control measure, improving the preventive health behavior and concerns of appropriate people cannot be overemphasized. In light of the above reasons, an interview survey was performed to clarify the relationships between the variables related to health behavior and those related to health beliefs on hepatitis B infection. A total of 509 housewives who were invited to a hepatitis B screening campaign was selected for the study. These women were separated into two groups :those who participated in the campaign(258 persons) and those who did not participate(251 persons). The results were as follows : 1. Variables of socio-demographic characteristics, cue to action, and health belief were significantly associated with variables of preventive health behavior on serological test for hepatitis B. 2. The participating group had higher degree of general knowledge, susceptibility, severity, benefit and health concerns of hepatitis B infection. 3. Results of multiple regression study with variables of health beliefs, cue to action, and socio-demographic characteristics showed that the total of those variables could explain 65.4% of preventive health behavior for hepatitis B. 4. Stepwise discriminant analysis study between the participating and nonparticipating group with all the detailed variables of health belief, cue to action, and socio-demographic characteristics resulted in a hit ratio of 89.5%.

돼지 신장세포(PK15)의 이종이식 거부반응에 대한 재조합 IL-18의 영향

최연실,김은미,김영관,박상연,심정현,윤도영,강형식,명평근 충남대학교 형질전환복제돼지연구센터 2004 논문집 Vol. No.8

Various cytokines including IL-1β, IL-2, IL-4, IL-10, IL-12p40, IFN-r, and TNF-α have been recently reported to play important roles in both host and donor cell activations during xenotransplantation. Interleukin (IL)-18, a proinflammatory cytokine, can induce IL-4 and IL-13 production in T cells, NK cells, B cells, mast cells, and basophils. IL-18 has the capacity to stimulate innate immunity and both Th1-and Th2- mediated responses, but little is known to involve in the xenograft rejection. In order to investigate the role of IL-18 in xenograft rejection, we transplanted the pig kidney (PK15) cells to C57BL/6 mouse with or without intraperitoneal injection of mouse recombinatant IL-18, It was analyzed the population of T cell, B cell and NK cell in the mice transplanted with PK 15 cells and recombinant IL-18 by flow cytometry. We found that splenic CD3+ T cells were increased in mice injected PKl5 cells with recombinant IL-18. These results suggest that recombinant IL-18 is critical in the xenograft rejection by increasing T cell population of the recipients.

6주간의 淸暑益氣湯 經口投與가 에너지대사 및 호르몬 변화에 미치는 영향

최용어,강명신,유종만,이규성,오재근,조준용 韓國體育大學校附屬 體育科學硏究所 1994 韓國體育大學校附屬 體育科學硏究所論文集 Vol.13 No.1

The purpose of this study was to investigate the effects of chung-seo-ik-gi -tang administration on the metabolic responses and hormones in 18 healthy-male elite boxes. All subjects were divided randomly with two groups, Chung-sea-ik-gi-tang Group(N=18) and placebo group(N=18) and perfored with 70% of HR max using bycicle ergometer unfil exhaustion. During the submaximal exercise, heart rate was maesured every two min. The blood samples were collected from antecubital vein by 10ml syranges(6ml/each) before immediately after exhaustion, recover-10 min, recover-20 min and recover-30 min. The samples were to analyzed for the level of glucose, lactate, TG, TC, HDL-C, insulin and catecholamine. The results of various blood parameters were summarized as follow; l. Energy substrates (plasma glucose, TG, TC, HDL-C) changes in group C were significantly different from group P. Plasma glucose in group C was significantly lowered at recover-10 min compared to group P (P<0.05). and also TG, TC and HDL-C in group C were significantly increased after 3 weeks compared to group P (P<0.05) whereas. Lactate accumulation in group C was significantly decreased after 3 weeks compared to group P (P<0.05). 2. Plasma insulin level was not showed significant difference between two groups. But insulin depression tendency after 3, 6 weeks in group C was allevated compared to group P. Increasing rate of norepinephrine in group C at Post-exhaustion after 3weeks lowered compared to group P. Norepinephrine in group C at rest periods after 3 weeks showed significant difference compared to group C. The results indicated that Chung-seo-ik-gi-tang had the effects of ergogenic aids on fatigue resistance and recovery from exhaustive exercise at the level of 70% HR max.

중소기업형 CIM시스템 구축을 위한 생산계획수립 및 실적파악 모듈

최후곤,신완선,장중순,서준성,여명구,안동근,김진봉 成均館大學校 科學技術硏究所 1996 論文集 Vol.47 No.2

This study Focuses on developing several modules involved in an integrated production information system for medium- or small-sized industries. The modules of order management, quality control, production scheduling, and shop management are executed for an example case industry. The potential values of this research includes that the major information modules to collect, analysis, and display production data and shop data for constructing the computer integrated manufacturing system(CIMS) are programmed with various features of medium- or small-sized industries

호텔기업의 로열티 프로그램이 몰입과 고객 애호도에 미치는 영향에 관한 연구

최우성,황명호 한국문화관광학회 2003 문화관광연구 Vol.5 No.2

In the hotel industry, the royalty (membership) program is very important because the profit or loss in their hotels income depends on it. The revenue from VIP membership takes 30~40% of total profits in the total hotel revenue. The utility value of the membership system is very powerful and hotels use this system to gain dominance over others. The hotels royalty program is a very important method in managing customers examining how to activate customer relationships, and analyzing how to affect customer loyalty. In the hotels royalty program, I researched how to influence level of commitment and loyalty.

품종 및 성숙 정도에 따른 박종자의 건열처리 반응성

최성민,이정명 경희대학교 생명자원과학연구원 2002 硏究論文集 Vol.22 No.-

수박 대목으로 사용되는 박종자의 발아특성과 건열처리효과를 과실의 숙도 및 건열처리후 저장기간에서 3품종을 공시하여 실험하였는데 셀트레이에서의 출협율을 보면 어느 품종에서나 과실의 성속도가 높은 품종이 종자의 충실도도 높고 발아세와 발아율이 모두 높게 나타났으며 이러한 차이는 다른 품종에서도 동일하였다. 이들 종자에 건열처리를 가하였을 경우 품종에 따라서 다양한 반응 차가 나타났다 즉 원앙참박에서는 건열처리 된 종자의 묘 출현율이 무처리종자보다 월등히 높았는데 이러한 차이는 오나숙종자 보다 미숙종자에서 더욱 크게 나타났다. 그러나 차후 다른 품종의 결과를 보면 건열처리가 오히려 모 출현율을 현저히 저하시켰다. Fully mature seeds of bottle gourd (Lagenaria siceraria) showed higher germination vigor and final emergence rate at compared to mature or immature seeds in all 3 cultivars tested. Dry heat treatment (DHT) for 3 days at 75℃ ignificantly reduced early and final seedling emergence rate in 'Gangryuk' and 'FR King Ⅱ' gourds regardless of the seed maturity. In 'Weonang' bottle gourd, however, DHT significantly increased the early and final seedling emergence rate as compared to the non-treated ones and this promotion effect was more pronounced in immature seeds as compared to mature or fully-mature seeds.