UHF RFID 태그 칩용 저전력 EEPROM설계

이원재,이재형,박경환,이정환,임규호,강형근,고봉진,박무훈,하판봉,김영희,Yi, Won-Jae,Lee, Jae-Hyung,Park, Kyung-Hwan,Lee, Jung-Hwan,Lim, Gyu-Ho,Kang, Hyung-Geun,Ko, Bong-Jin,Park, Mu-Hun,Ha, Pan-Bong,Kim, Young-Hee 한국정보통신학회 2006 한국정보통신학회논문지 Vol.10 No.3

본 논문에서 는 플래쉬 셀을 사용하여 수동형 UHF RFID 태그 칩에 사용되는 저전력 1Kb 동기식 EEPROM을 설계하였다. 저전력 EEPROM을 구현하기 위한 방법으로 다음과 같은 4가지 방법을 제안하였다. 첫째, VDD(=1.5V)와 VDDP(=2.5V)의 이중 전원 공급전압 방식을 사용하였고, 둘째, 동기식 회로 설계에서 클럭(clock) 신호가 계속 클럭킹(clocking)으로 인한 스위칭 전류(switching current)가 흐르는 것을 막기 위해 CKE(Clock Enable) 신호를 사용하였다. 셋째, 읽기 사이클에서 전류 센싱(current sensing) 방식 대신 저전력 소모를 갖는 clocked inverter를 사용한 센싱 방식을 사용하였으며, 넷째, 쓰기 모드시 Voltage-up 변환기(converter) 회로를 사용하여 기준전압 발생기(Reference Voltage Generator)에는 저전압인 VDD를 사용할 수 있도록 하여 전력 소모를 줄일 수가 있었다. $0.25{\mu}m$ EEPROM 공정을 이용하여 칩을 제작하였으며, 1Kb EEPROM을 설계한 결과 읽기 모드와 쓰기 모드 시에 소모되는 전력은 각각 $4.25{\mu}W$와 $25{\mu}W$이고, 레이아웃 면적(layout area)은 $646.3\times657.68{\mu}m^2$이다. In this paper, a low-power 1Kb synchronous EEPROM is designed with flash cells for passive UHF RFID tag chips. To make a low-power EEPROM, four techniques are newly proposed. Firstly, dual power supply voltages VDD(1.5V) and VDDP(2.5V), are used. Secondly, CKE signal is used to remove switching current due to clocking of synchronous circuits. Thirdly, a low-speed but low-power sensing scheme using clocked inverters is used instead of the conventional current sensing method. Lastly, the low-voltage, VDD for the reference voltage generator is supplied by using the Voltage-up converter in write cycle. An EEPROM is fabricated with the $0.25{\mu}m$ EEPROM process. Simulation results show that power dissipations are $4.25{\mu}W$ in the read cycle and $25{\mu}W$ in the write cycle, respectively. The layout area is $646.3\times657.68{\mu}m^2$.

A comparative study on the inhibitory effects of mast cell-mediated allergic reactions by artificially cultured and wild Acanthopanax senticosus

Yi, Jin-Mu,Jeong, Hyun-Ja,Shim, Kyung-Shik,Lee, Kang-Yong,Kim, Jeong-Sook,Zheng, Cui,Tomoko, Jippo,Lee, Young-Mi Kyung Hee Oriental Medicine Research Center 2000 International journal of oriental medicine Vol.1 No.2

We compared the effect between CAS and WAS(root, stem) on mast cell-mediated allergic reaction. CAS, WAS-root and WAS-stem, significantly inhibited compound 48/80-induced systemic allergic reaction(1g/kg) and histamine release from RPMC(1mg/ml). CAS, WAS-root and WAS-stem also inhibited passive cutaneous anaphylactic reaction. In addition, IgE-induced $TNF-{\alpha}$ secretion from RBL-2H3 was inhibited by pretreatment of CAS, WAS-root or WAS-stem$(0.01{\mu}g/ml)$. Taken together, inhibitory effect on mast cell-mediated allergic reactions of WAS-root is greater than those of WAS-stem but less than those of CAS.

Characterization of Inkjet-Printed Silver Patterns for Application to Printed Circuit Board (PCB)

Shin, Kwon-Yong,Lee, Minsu,Kang, Heuiseok,Kang, Kyungtae,Hwang, Jun Young,Kim, Jung-Mu,Lee, Sang-Ho The Korean Institute of Electrical Engineers 2013 Journal of Electrical Engineering & Technology Vol.8 No.3

In this paper, we describe the analysis of inkjet-printed silver (Ag) patterns on epoxy-coated substrates according to several reliability evaluation test method guidelines for conventional printed circuit boards (PCB). To prepare patterns for the reliability analysis, various regular test patterns were created by Ag inkjet printing on flame retardant 4 (FR4) and polyimide (PI) substrates coated with epoxy for each test method. We coated the substrates with an epoxy primer layer to control the surface energy during printing of the patterns. The contact angle of the ink to the coated epoxy primer was $69^{\circ}$, and its surface energy was 18.6 $mJ/m^2$. Also, the substrate temperature was set at $70^{\circ}C$. We were able to obtain continuous line patterns by inkjet printing with a droplet spacing of $60{\mu}m$. The reliability evaluation tests included the dielectric withstanding voltage, adhesive strength, thermal shock, pressure cooker, bending, uniformity of line-width and spacing, and high-frequency transmission loss tests.

Risk Assessment of 5-Chloro-2-Methylisothiazol-3(2H)-One/2-Methylisothiazol-3(2H)-One (CMIT/MIT) Used as a Preservative in Cosmetics

Kim, Min Kook,Kim, Kyu-Bong,Lee, Joo Young,Kwack, Seung Jun,Kwon, Yong Chan,Kang, Ji Soo,Kim, Hyung Sik,Lee, Byung-Mu Korean Society of ToxicologyKorea Environmental Mu 2019 Toxicological Research Vol.35 No.2

The mixture of 5-chloro-2-methylisothiazol-3(2H)-one (CMIT) and 2-methylisothiazol-3(2H)-one (MIT), CMIT/MIT, is a preservative in cosmetics. CMIT/MIT is a highly effective preservative; however, it is also a commonly known skin sensitizer. Therefore, in the present study, a risk assessment for safety management of CMIT/MIT was conducted on products containing 0.0015% of CMIT/MIT, which is the maximum MIT level allowed in current products. The no observed adverse effect level (NOAEL) for CMIT/MIT was 2.8 mg/kg bw/day obtained from a two-generation reproductive toxicity test, and the skin sensitization toxicity standard value for CMIT/MIT, or the no expected sensitization induction level (NESIL), was $1.25{\mu}g/cm^2/day$ in humans. According to a calculation of body exposure to cosmetics use, the systemic exposure dosage (SED) was calculated as 0.00423 mg/kg bw/day when leave-on and rinse-off products were considered. Additionally, the consumer exposure level (CEL) amounted to $0.77512{\mu}g/cm^2/day$ for all representative cosmetics and $0.00584{\mu}g/cm^2/day$ for rinse-off products only. As a result, the non-cancer margin of safety (MOS) was calculated as 633, and CMIT/MIT was determined to be safe when all representative cosmetics were evaluated. In addition, the skin sensitization acceptable exposure level (AEL)/CEL was calculated as 0.00538 for all representative cosmetics and 2.14225 for rinse-off products; thus, CMIT/MIT was considered a skin sensitizer when all representative cosmetics were evaluated. Current regulations indicate that CMIT/MIT can only be used at concentrations 0.0015% or less and is prohibited from use in other cosmetics products. According to the results of this risk assessment, the CMIT/MIT regulatory values currently used in cosmetics are evaluated as appropriate.

전해공정에 의한 피혁폐수의 질소제거

이무강,김영철,강현이 慶星大學校 環境問題硏究所 1997 環境硏報 Vol.7 No.1

This study was conducted to investigate the removal efficiency of COD and NH??-N from the discharge of tannery industrial complex wastewater treatment plant by electrochemical oxidation process, which was used as pretreatment process for enhancing the biological removal efficiency. On the variation of electric current 1,2, and 4A, the removal efficiencies of COD after the lapse of 2hr of electrolysis were 9.0, 27.8, and 66.0%, and those of NH??-N after the lapse of 3hr reaction were 30%, 61% and 99%, respectively. The result of pH effect demonstrated that COD removal efficiency was not much influenced by initial pH but NH??-N removal was very effective in the initial pH4. Through the electrolysis at constant pH conditions(pH4, 8, and 10), it was observed that pH10 was the best reaction condition for NH??-N removal In the result of the effect of NaCl addition as much as 0, 1, 3, and 7g, the removal efficiencies of COD were 27.8, 82.0, 88.0, and 95.0% and those of NH??-N were 33.0, 67.4, 70.8, and 99.97% after the laspe of 2hr reaction, respectively.

RBC工程에 依한 LAS와 都市 混合廢水의 處理

李武康,金薰洙 慶星大學校 1988 論文集 Vol.9 No.2

In this study, though the biodegradation rate of the surfactant itself is important, of which influence to the sewage treatments is important too, and therefore, when the municipal sewage including surfactant(LAS) is treated by the activaed sludge process, large quantity of bubble is produced by aeration in the reaction tank ,and also the sludge bulking phenomenon is caused in the sedimentation tank, so the municipal sewage is applied and treated by RBC which has no such faults and its results have been obtained as follow: 1) when the LAS concentration is 0,10,50,100,200 �/�, the COD removal efficiency is 90,87,85,81 and 75%, so it is recognized that as the cocentration increase, COD removal efficiency decrease. 2) when the hydraulic retention time is 0.1 day, more than about 80% can be removed when LAS is not added, while the more the added concentration of LAS increase, the slower the biodegradation rate becomes, so it is understood that more than 0.4day is required in order to obtain the same removal efficiency as the condition of the without added LAS. 3) when LAS concentration is 0,50 and 100�/�, the sludge yield parameter, Y, is 1.086, 0.949 and 0.792�VSS/�COD respectively, and endogenous respiration parameter, kd, is 0.078, 0.088 and 0.163day?. The reaction rate constant, k, is 0.087, 0.415 and 0.415 and 0.155day? and the half velocity constant, Ks, is obtained 1187,710.1, and 360.7�COD/�respectively.

Alachlor 農藥廢水의 오존酸化

李武康,黃泰九 경성대학교 1989 論文集 Vol.10 No.1

The batch and cotinuous study were performed to determine the optimum condition for the ozonization of alachlor. In the batch study, alachlor removal per unit ozone application rate was found to be 1.44 when the initial concentration of alachlor was 5 folds or greater than the ozone concentration. Alachlor removal was inhibited with the addition of NH??Cl and methanol. The removal, however, increased with pH and temperature. A continuous ozone oxidation study was also performed with alachlor wastewater. The COD removal efficiency was 21.4% at 10 minutes of reaction time, but alachlor removal was 3.8% only.

단일반응조에서 이상 생물막법에 의한 질소제거

이무강,김영철,강호진 慶星大學校 環境問題硏究所 1996 環境硏報 Vol.6 No.1

The effects of C/N ratios on COD removal rate, nitrification and denitrification were investigated by using anoxic reactor and oxic reactor in two phase biofilm. The C/N ratios of reactors was controlled to the level of 12.1/1, 6/1, 3/1, 1.6/1, respectively. The nitrification and denitrification using two phase biofilm in single reactor system reached the following results. The effects of DO on nitrification and denitrification were not influenced by DO concentration, the DO concentration of anoxic reactor and oxic reactor showed 2.3∼5.0㎎/a, 0.2∼0.9㎎/1, respectively. The pH of anoxic reactor and oxic reactor reached most suitable pH at 7.2∼8.4. The COD removal rate increased according to increasing C/N ratios from 3/1 of C/N ratio increased ammonia removal rate at 43%∼78%. The denitrification rate reached the maximum at 40.9%∼51.4%, when C/N ratios were 3/1∼6/1. At 12.1/1 of C/N ratio, in generlly nitrogen removal used synthetic biomass, relatively decreased denitrification rate.

폴리에스테르 제조폐수의 전해처리

이무강,김영철,임경천,김현국 경성대학교 생산기술연구소 1997 생산기술연구지 Vol.4 No.-

This study emphasize on removal of organic matter by indirect oxidation process. In the electrolytic treatment, ??, ?? is producted by chloride. ??, ?? is used to organic matter oxidation. This study was conducted for the effects of organic matter oxidation, electrolysis time, electric current, ?? concentrations, and pH due to production of ??, ?? by electrolysis. Also, possibility on the second treatment by activated carbon adsorption was investigated. The results obtained were as follows : pH was rapidly increased less than 10 minutes, and was maintained after 30 minutes. When the temperature was not constantly maintained. The removal rate of TOC was increased up to 32% with the increasing of ?? concentrations and the increasing of electrolytic current. Effects of pH was not observed. When electrolysis was not carried out, adsorption constant k and 1/n were 0.017, 1.684, respectively. After the electrolysis with 1, 3, 5, 8A electrolysis, k and 1/n were 0.02, 0.022, 0.025, 0.018, 0.874, 0.518, and 0.887, 0.77, respectively. This result indicated that the wastewater included some material which is difficult to decompose. This wastewater need to pretreatment rather than independent electrolysis.

長期 曝氣法에 依한 LAS 含有 都市下水의 處理時 設計 Parameter의 決定

李武康,許烈,崔基園 慶星大學校 環境問題硏究所 1991 環境硏報 Vol.1 No.1

This study was conducted by using the mixture of synthetic wastewater, linear alkyl benzene sulfonate(LAS) and Glucose as influent substrate. The mean value of influent COD, LAS concentration was maintained 540mg/ℓ, 25mg/ℓ, respectively. Reactor temperature was maintained constantly as 25±10℃ and hydraulic retention time was varied from 1 day to 2.5 day. The kinetic parameter such as half-velocity contant Ks, maximum substrate utilization rate qmax, sludge yield coefficient Y, endogenous respiration coefficient kd, specific substrate removal rate constant k were investigated through the experiment with bench-scale Extended Aeration process. The Kinetic parameters and treatment efficiency were as follows, * In the influent substrate concentration (540mg/ℓ), the estimated values for the kinetic parameters were Ks=42.96mg/ℓ,qmax=0.444 day-1, Y=0.292, kd=0.04 day¹, k=0.005 day-1 respectively. *The LAS removal rate was over 84% with Hydraulic retention time 1 day, 1.5 day, 2.5 day respectively. The substrate removal rate was became to 94% with 1 day 2.5 day hydraulic retention time, respectively.