Reduction of Bacillus cereus Contamination in Biofilms on Stainless Steel Surfaces by Application of Sanitizers and Commercial Detergent

Lee, Min-Jeong,Ha, Ji-Hyoung,Kim, Yong-Su,Ryu, Jee-Hoon,Ha, Sang-Do The Korean Society for Applied Biological Chemistr 2010 Applied Biological Chemistry (Appl Biol Chem) Vol.53 No.1

We established the effectiveness of a washing, detergent and sanitizer treatments for reducing Bacillus cereus (B. cereus) contamination in biofilms on stainless steel surfaces. A water treatment did not affect biofilms and chlorine treatments at 200 ppm for 10 min and 300 ppm for 5 min, iodophor at 200 ppm for 10 min, and QAC at 400 ppm for 10 min were used to eliminate all B. cereus cells. B. cereus cells after detergent treatment were eliminated by chlorine at 100 ppm for 10 min, 200 ppm for 5 min, and 300 ppm for 3 min, and with iodophor at 100 ppm for 10 min and 200 ppm for 10 min, and QAC at 400 ppm for 10 min.

이동형 스크러버를 이용한 암모니아 및 톨루엔의 제거 효율

김재영 ( Jae-young Kim ),김장윤 ( Jang-yoon Kim ),이연희 ( Yeon Hee Lee ),김민선 ( Min Sun Kim ),김민수 ( Min-su Kim ),김현지 ( Hyun Ji Kim ),류태인 ( Tae In Ryu ),정재형 ( Jae Hyeong Jeong ),황승율 ( Seung-ryul Hwang ),김균 ( Ky 한국환경농학회 2018 한국환경농학회지 Vol.37 No.1

본 연구는 국내에서 다량 취급되고 있는 암모니아 및 톨루엔을 흄 상태로 노출시킨 후 흡수/흡착방법을 달리한 이동형 스크러버를 이용해 각 유해화학물질의 제거효율을 비교 분석하였다. 이동형 스크러버는 기 개발된 장치를 개선하여 와류세정에 의한 흡수, 유입풍속 조절의 장점을 살리고, 활성탄 및 카본필터를 통한 기체상 유해화학물질의 흡착방법 도입을 통해 단점을 보완하였다. 개선된 장치는 기초성능평가를 통해 적정 제어풍속이 검증되었고, 5% 암모니아수 용액을 흄 상태로 노출시켜 후드 흡입부, 송풍기 배출부 및 세정기가 정상 작동함을 확인하였다. 흡수/흡착방법에 따른 암모니아 제거효율은 90분 경과 후 C≥PCA>SWA 순으로 가장 우수한 SWA 군의 노출 농도별 제거 효율은 시간이 경과할수록 노출 농도와 무관하게 배출 농도는 증가되었고, 세정액의 pH는 산성에서 염기성으로 변화되었다. 또한, 시간 경과에 따른 노출 농도 별 세정액의 pH 변화와 배출구 농도 변화 사이에 0.9429~0.9491 수준의 정의 상관관계를 나타내었다. 흡착방법에 따른 톨루엔의 제거 효율은 초기 10분 경과 후 배출구농도에서 C>CMA≥GCA 순을 나타내다 90분 경과까지 일정한 농도로 유지되었다. 가장 우수한 GCA 군의 노출 농도 별 제거 효율은 초기 10분 경과 시 노출 농도에 비례하여 배출 농도가 높은 경향이었다. 이와 같은 결과를 통해 개선된 이동형 스크러버는 중화반응에 의해 산성 또는 염기성 유해화학물질의 제거뿐 아니라, 활성탄 등의 흡착기능 개선을 통해 VOCs 제거에도 효과적이었다. 하지만, 실제 현장에서 활용이 가능하도록 세정액 pH를 지속적으로 유지하여 연속적으로 흡수 제거할 수 있는 방법과 노출되는 화학물질 농도와 흡착제의 관계에서 파괴점, 포화점, 흡착속도 등의 물리적인 요소가 추가적인 연구를 통해 도출되어야 할 것이다. BACKGROUND: The mobile vortex wet scrubber was developed to remove the harmful chemicals from accidental releases. However, there was a disadvantage that it was limitedly used for volatile organic compounds (VOCs) such as toluene according to the physicochemical properties. This study compared the removal efficiencies of an improved mobile scrubber on toluene and ammonia by applying diverse adsorption and absorption methods. METHODS AND RESULTS: The removal efficiencies on harmful chemicals were examined using various adsorption and absorption methods of water vortex process (C), phosphoric acid-impregnated activated carbon adsorption (PCA), pH-controlled water (pH 2.5) vortex process absorption with sulfuric acid (SWA) after ammonia exposure, granular activated carbon adsorption (GCA), and activated carbon mat adsorption (CMA) after toluene exposure. As a result, the best removal efficiency was shown in the SWA for ammonia and GCA for toluene. Also, the SWA and GCA methods were compared with different concentration levels. In the case of ammonia exposure (5, 10 and 25%), there was no difference by concentration levels, and the concentration in the outlet gradually increased, with pH change from acid to base. In the case of toluene exposure (50, 75 and 100%), the outlet concentration was higher relative to the exposure concentration in the initial 10 min, but the outlet concentration was remained steady after 10 min. CONCLUSION: The newly improved mobile scrubber was also effective in removing VOCs through adsorption techniques (activated carbon, activated carbon fiber, carbon mat filter etc.), as well as removing acid-base harmful chemicals by neutralization reaction.

Cascade-Neuro-Fuzzy-PID 적응제어에 대한 연구

유민수,선우창신 全南大學校 觸媒硏究所 2003 觸媒硏究 論文集 Vol.24 No.-

The Cascade-Neuro-PID controller has been developed and applied for the gas heating process. The parameters of the master PID controller were obtained as the outputs of the neural networks using system jacobian calculated from neural identifier. To do not fall in local minimum point optimized parameters of Neuro-PID controller, learn rate of neural network was calculated by fuzzy logic algorithm. In simulation results, the Cascade-Neuro-Fuzzy-PID controller has shown the good robust control response characteristics without overshoots.

광폭하구에서의 오염물질 확신이송 모형 (BAYQUAL) 개발

류병로,한양수,두민호,유병연 大田産業大學校 1998 한밭대학교 논문집 Vol.15 No.1

The objective of this research is to develop the water quality simulation model (BAYQUAL) that deal with the physical and chemical aspects of rate/behavior of pollutants in the bay BAYQUAL is a two dimensional, time-variable finite element water quality model. This modeling system was designed to provide the generality and flexibility necessary for analyzing a verity of water quality problems in a diverse set of water bodies. The algorithm is composed of a hydrodynamic module(BAYQUAL) which solves the equations of motion and continuity, a pollutant dispersion module which solves the dispersion-advection equation. The applicability and feasibility of the model are discussed by applications of the model to the Kwangyang bay of South Coastal Waters of Korea. Based on the field data, the BAYQUAL model was calibrated and verified. The results were in good agreement with measured value within relative error of 3% for COD. Numerical simulations of velocity components and tide amplitude were agreed closely with the actual data.

용존산소농도 예측을 위한 추계학적 다중 입력모형

류병로,한양수,두민호,조성근 大田産業大學校 1998 한밭대학교 논문집 Vol.15 No.1

In the most cases we analyze a single time series without explicitly using information contained in the related time series In many forecasting situations, other events will systematically influence the series to be forecasted(the dependent variables), and therefore, there is need to go beyond a univariate forecasting model. Thus, we must build a forecasting model that incorporates more than one time series and introduces explicitly the dynamic characteristics of the system. Such a model in called a multiple time series model or transfer function model. The purpose of this study is to develop the stochastic stream water quality model of Puyea station in Keum river system. The performance of the multiplicative ARIMA model and the multiple input-single output transfer function model were examined through comparisons between the historical and generated monthly dissolved oxygen series. The result reveal that the multiple input-single output model lead to teh improved accuracy.

비대칭 CTA막을 이용한 전위차법 Adenosine 생체계측기의 개발

유민수 全南大學校 觸媒硏究所 1998 觸媒硏究 論文集 Vol.20 No.-

Two kinds adenosine sensors based on asymmetric cellulose triacetate membranes are made. The asymmetric membranes are formed by first casting a thin layer of cellulose triacetate without carrier, hydrolyzing this film with base, and then on the other side casting a second layer of cellulose triacetate containing the membrane active component. The hydrolyzed surface of asymmetric membranes is activated in aqueous solution with carbonyldiimidazole. One kind of adenosine sensors is made by immobilization of adenosine deaminase on these membranes (hydroxylated method). The other is made by immobilization of adenosine deaminase on aminated membranes (aminated method). The response of the hydroxylated sensor is faster than the aminated sensor. Linearity, sensitivity and detection limits of two kinds of sensors are similar. Therefore hydroxylated method is better than aminated method.

전류제어형 PWM컨버터를 이용한 동기발전기용 여자시스템에 관한 연구

장수진,류동균,서민성,김준호,원충연,이진국 성균관대학교 2003 학술회의지원논문목록집 Vol.2003 No.-

동기발전기 출력전압은 여자시스템의 계자전류 제어에 의해 일정하게 유지된다. 고주파 PWM 컨버터(전류제어모드 buck컨버더)형태의 여자시스템은 부하변동이 발생하였을 때 동기발전기의 계자전류를 제어하게 된다. 이 논문은 정상상태 및 과도상태에서의 안정화를 개선하기 위하여 여자시스템의 설계 및 실험에 대해 다루었다. 시뮬레이션 및 실험 결과는 제안된 여자시스템이 50kW 동기발전기의 DVR에 의해 응답시간이 개선되었음을 보여주었다. The output voltage of synchronous generator is regulated constantly by field current control in excitation system. High frequency PWM converter (current control mode buck conveter) type excitation system for synchronous generator is able to control exciter current when the load change happened. This paper deals with the design and evaluation of the excitation system for a synchronous generator to improve the steady state and transient stability. The simulation and experimental results show that the proposed excitation system is able to improve the response time by the DVR(digital voltage regulator) of 5O[kW] synchronous generator.

하악골 절제술후 재이식된 돌결자가골 재이식 : 치험 3례

김 식,김수관,김운규,김수민,류종희,이준길,조경안,김수흥,정태영,여환호 대한악안면성형재건외과학회 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.2

We described three cases of immediate reimplantation of a frozen-thawed autogenous mandible composed of a mixture of iliac bone, marrow, and particulate hydroxyapatite in tumors of the mandible. Acceptable outcomes were obtained in three patients who underwent immediate autogenous mandibular graft reconstruction. The conditions leading to successful outcome of the procedure are also discussed. Reimplantation of frozen autogenous lesioned mandible was performed in three patients with mandibular tumors. Two reimplanted grafts survived without complications following surgery. One case had postoperative infection that resolved with appropriate antibiotic treatment. There were no recurrences of the primary lesions. Satisfactory facial contour after surgery was achieved. These results are most promising, and we believe that, with further refinement, this technique will offer a new and acceptable modality for facial reconstruction in patients with cancer.

퍼지 뉴런에 의한 연속교반탱크가열기의 신경망 온도 제어

김종대,박종호,유민수 전남대학교 촉매연구소 2001 觸媒硏究 論文集 Vol.22 No.-

To improve the performance of neural adaptive control method, fuzzy neuron has been developed and applied for the temperature control of CSTH with large time delay. In the on-line neural adaptive control, the slope of sigmoid transfer function has tuned out to be important factor for the characteristics of control response. Fuzzy neuron has changed the shape of transfer function for the response of system in real-time. In the case of using fuzzy neuron of neural controller, the overshoots and the response time were better reduced than using general neuron.

인공신경망을 이용한 PID 제어기의 자동조정

김종대,김동오,유민수 전남대학교 촉매연구소 2001 觸媒硏究 論文集 Vol.22 No.-

The Auto-tuning PID controller based on neural networks has been developed and applied for the temperature control of continuous stirrer tank heater(CSTH) with large time delay. The parameter of the PID controller is obtained as the outputs of the neural networks using system jacobian calculated from neural identifer. In simulation and experimental results, the neural Auto-tuning PID controller has shown the good response characteristics without overshoots. The control output of the proposed controller with significant disturbance system has shown robust control response by simulation.