• Title/Summary/Keyword: BCM

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The Effects of DO, HRT, and Media Packing Ratio on Nitrogen Removal Efficiency in BCM-ASR System (고정상 담체를 충전한 활성슬러지 공정에서 DO농도와 HRT 및 담체 충전율 변화가 질소 제거효율에 미치는 영향)

  • Whang, Gye-Dae;Han, Bong-Seok
    • Journal of Korean Society on Water Environment
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    • v.24 no.6
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    • pp.659-669
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    • 2008
  • Two sets of four parallel activated sludge reactors (ASRs) maintaining an MLSS of 3000 mg/L were operated to investigate the effect of DO, HRTs and bio-contact media (BCM) packing ratios on the removal efficiency of organic matters and nitrogen. Packing ratios of BCM to BCM-ASR systems 1, 2, 3, and 4 were 0% (suspended growth only), 10%, 15% and 20%, respectively. All systems were operated at an HRT of 4 hr, 6 hr, and 8 hr, respectively; DO concentration was maintained 0.5~1.0 mg/L and 1.5~2.0 mg/L for each HRT condition. In terms of TSS, TCODcr and SCODcr removal efficiency, all systems had a similar level of the removal efficiency under varied HRTs, and DO. But organic removal efficiency of systems with BCM was approximately 3~5% higher than systems without BCM at the same HRT and the DO. About the nitrification efficiency, with high DO (1.5~2.0 mg/L), as HRT (4 hr, 6 hr, 8 hr) or BCM packing ratio increased, the slight increment of nitrification efficiency was observed. However, under the low DO (0.5~1.0 mg/L), increase of BCM packing ratio and HRT resulted in large increase of the nitrification efficiency. At the same HRT and BCM packing ratio, the nitrification efficiency increased greatly with up to 15% as DO increased. When the HRT increased from 4hr to 8hr, the denitrification efficiency slightly increased by 5~10% only, under all DO conditions. Systems with BCM had higher denitrification efficiency, ranged 62.7~91.1% than systems without BCM showed 32.1~65.6%. And the increase in BCM packing ratio from 10% to 20% resulted in about 14~16% denitrification efficiency increment. BCM packing ratio showed great effect on the denitrification. The increase of the DO (from 0.5~1.0 mg/L to 1.5~2.0 mg/L) at the same HRT and BCM packing ratio resulted in slight decrease of denitrification efficiency with up to 7% for systems with BCM. But for systems without BCM, the denitrification efficiency decreased with up to 28%. In all system, the denitrification efficiency had more influence on the TN removal efficiency than nitrification efficiency. So, BCM packing ratio (0%, 10%, 15%, 20%) has greater effect on the TN removal than HRT and DO. The TN removal efficiency increased as packing ratio of BCM increased with up to 45%. As a result, the highest TN removal efficiency was observed 73.7% at the condition showed the highest denitrification efficiency that DO of 0.5~1.0 mg/L, an HRT of 8 hr, and 20% of BCM packing ratio was maintained.

Transmitted Reference UWB Systems Based on Block-Coded Modulation (블럭부호변조 기반의 Transmitted Reference 광대역 통신 시스템)

  • Min, Seungwook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.3
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    • pp.289-293
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    • 2013
  • In the noncoherent methods for UWB-IR (ultra-wideband impulse radio), block coded modulation (BCM) is better than the transmitted reference (TR) systems in terms of the energy efficiency and data rate. However, even BCM suffers from the performance degradation in the presence of strong inter-frame interference and inter symbol interference. We propose the transmitted reference based on the BCM (TR-BCM) which is the hybrid system of TR and BCM. Performance evaluation shows that the performance of TR-BCM is better than that of BCM in the high SNR range.

The Effect of the Attached Growth in Aerobic Reactor on Nitrogen Removal in A2/O processes (포기조에 충진된 고정상 담체가 A2/O공정에서 질소제거에 미치는 영향)

  • Whang, Gye-Dae;Bae, Sung-Hyun
    • Journal of Korean Society on Water Environment
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    • v.22 no.6
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    • pp.1022-1030
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    • 2006
  • Activated sludge reactors maintaining an MLSS of 3,000 mg/L and packed Bio Contact Media (BCM fixed beds) was studied in lab-scale to determine the optimal packing ratio and an HRT of aerobic reactor in terms of organic removal, nitrification, denitrification efficiencies. At all HRTs of 3 hr, 5 hr, 7 hr respectively, reactors without BCM, control reactors, had the lowest TCODcr removal efficiency about 74.6%, and reactors with the BCM packing ratios of 10%, 15%, 20% had a greater TCODcr removal efficiency above 81.4%. As HRT decreased, the TCODcr removal efficiency decreased also in all reactors. However, a better utilization of TCODcr even at a higher organic loading was observed in reactors with BCM. The nitrification efficiency at all reactors was greater than 94%, and reactor with 20% packing of BCM had the highest nitrification efficiency at 97.9% while the TKN loading increased at $0.085mgTKN/m^3{\ast}day$ as HRT decreased, In terms of denitrification efficiency, the reactor without BCM ranged from 11.6% to 13.7%, and the reactors with BCM ranged from 28.3% to 63.4% which suggests that the more BCM is packed in the reactors, the higher the denitrification efficiency is achieved. Two parallel $A^2/O$ systems maintaining an MLSS of 3,000 mg/L were operated to investigate the effect of BCM packing ratio of 20% on organic removal, nitrification, denitrification efficiencies. Packing with BCM in system of aerobic reactor affected the SCODcr removal efficiency that increased from 73% to 78%. The nitrification efficiency for both systems with or without BCM was greater than 95%. The denitrification efficiency of systems with BCM and without BCM was 85.8% and 81.8%, respectively which appears that the denitrification efficiency was increased slightly by packing BCM. Compared denitrification efficiency in $A^2/O$ system to previous experimental study with activated sludge reactors operates with the same HRT $A^2/O$ system showed only 29% greater denitrification efficiency. It suggests that $A^2/O$ system with BCM can achieve a similar level of denitrification efficiency when the HRT of anoxic reactor is decreased to some extent.

A Study on How to Effectively apply BCMS for small-scale manufacturing under 50 employees (50인 이하 소규모 제조업에 대한 효과적인 BCMS 적용)

  • Lee, Dae-Hyeong;Cheung, Chong-Soo
    • Proceedings of the Korean Society of Disaster Information Conference
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    • 2017.11a
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    • pp.255-256
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    • 2017
  • 본 논문에서는 50인 이하 소규모 제조업에 대해 어떤 방법으로 접근하는 것이 BCMS를 적용 하는데 효과적인지 연구하였다. BCMS의 적용범위가 상당히 광범위하고 현재 BCMS를 적용하고 있는 기업의 규모는 대부분 크며, 기업인들의 인식도 큰 규모만이 BCMS가 적용될 수 있다고 믿고 있다. 이에 실질적으로 한국의 기업군을 대부분 차지하고 있는 50인 이하의 제조업이 어떻게 BCMS를 적용하는 것이 효과적인지를 개발하여 소규모 기업도 어떠한 상황 하에서도 사업이 지속가능할 수 있도록 BCMS를 적용 하고자 한다. 일단 50인 이하 소규모 업체는 조직의 상황이 대기업이나 중견기업에 비해 간단하다. 또한 이해관계자도 대부분 많지 않다. 그렇기 때문에 BCMS를 수립하기 위해 파악하여야 할 핵심 업무나 관련 리스크도 많지 않을 것이다. 여기에 착안을 하여 기존에 대부분 갖추고 있는 품질, 환경, 안전보건시스템과 연계하여 사업연속성관리 시스템을 구축하면 50인 이하 기업도 별도의 추가시스템이 아닌 통합시스템의 일환으로 손쉽게 BCMS를 적용하여 어떠한 리스크에도 사업의 연속성을 갖출 수 있는 능력을 가질 것이다. BCMS에서 요구하는 사항에 대해 개별적인 접근방식보다 기존에 갖추고 있는 시스템을 적용하여 통합시스템 접근방식이 키포인트이다.

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Study on Evaluation Factors Determining Satisfaction and Revisiting of Broadcasting Contents Market (방송콘텐츠마켓 만족도와 재방문에 미치는 평가요인: 부산콘텐츠마켓(BCM) 사례를 중심으로)

  • Gu, Jong-Sang;Lee, Wan-Soo;Lee, Jin-Ro
    • Korean journal of communication and information
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    • v.52
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    • pp.111-134
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    • 2010
  • This paper explored satisfaction and revisiting of participants on Busan Contents Market(BCM) programme in 2009. Specifically, this study conducted regression analysis for finding satisfaction and revisiting factors on main events, broadcasting-telecom convergence forum, broadcasting business marketing forum, world culture contents forum and BCM academy. Results show as following. Firstly, Participants satisfied on comfortable lodging and possibilities as international events, but not satisfied on facilities, managements, public relations, contents and service. In particular, regional attraction and interpretation service are one of factors for revisiting in BCM main events. Secondly, one of competition factors for revisiting intention in BCM main events is production and investment. Thirdly, contents, theme and qualities of presenters and discussants are main factors for revisiting in BCM. Fourthly, satisfaction degree on education contents and lectures in BCM academy is high and contents, time, line up of lectures analyzed as determined factor for revisiting. Fifthly, documentary planning, production and marketing with international investors drive to induce revisiting BCM. We discussed motivation and utility values for revisiting of broadcasting contents market.

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A Study on the Effect of an HRT of Anoxic Reactors on Organic Matter and Nitrogen Removal in A2/O Processes with Bio Contact Media in Aerobic Tank (호기조에 고정상 담체를 충진한 A2/O공정에서 무산소조 체류시간 변화가 유기물질 및 질소 제거에 미치는 영향)

  • Whang, Gye-Dae;Han, Bong-Seok
    • Journal of Korean Society on Water Environment
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    • v.23 no.4
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    • pp.451-457
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    • 2007
  • Four parallel $A^2/O$ systems maintaining an MLSS of 3,000 mg/L were operated to investigate the effects of varying an HRT of anoxic reactors and packing Bio contact media (BCM, fixed beds) in aerobic reactors on organic matter removal and nitrification/denitrification efficiencies. All systems were operated under conditions that the external recycle ratio was kept 0.5 Q while the internal recycle ratio was changed 1.0 Q to 1.5 Q with that $NH_4-N$ concentration of feed was increased to 40 mg/L by adding $NH_4Cl$. In terms of TSS and TCODcr removal efficiency, both systems with BCM and a system without BCM, respectively, had a similar level of the removal efficiency under varied HRTs of anoxic reactors (0.6 hr, 1.3 hr, 2 hr, 2 hr; control, without BC M) showing that varying an HRT of anoxic reactors did not affect the removal efficiency. While SCODcr removal efficiency of systems with BCM was improved approximately 4~5% at the same HRT of anoxic reactor, the removal efficiency of system with BCM was slightly decreased by reducing an HRT of anoxic reactor. The nitrification efficiency for both systems with BCM and a system without BCM was above 94% showing that packing BCM in aerobic reactors and varying an HRT of anoxic reactors did not affect the efficiency significantly despite of increasing $NH_4-N$ concentration of feed. The denitrification efficiency increased from 81.4% to 85.4% at system with BCM while the efficiency decreased when a shorter HRT of anoxic reactors was kept. The excellent effluent quality for $NO_3-N$ concentration was observed although the $NO_3-N$ concentration increased in anoxic reactors that $NH_4-N$ concentration of feed sufficiently converted into nitrate through nitrification. As a result, packing 20% BCM to an aerobic reactor with HRT of 1.3 hr of anoxic reactor in $A^2/O$ system can achieve a similar level of nitrogen removal efficiency in $A^2/O$ system which the aerobic reactor had no BCM and HRT of 2 hr for anoxic reactor is maintained.

A Comparative Study of Catalytic Ozone processes for Removal of Refractory Organics (난분해성 유기물질 제거를 위한 오존/촉매 공정의 비교에 관한 연구)

  • Lee, Gyu-Hwan;Lee, Yu-Mi;Rhee, Dong-Seok
    • Journal of Industrial Technology
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    • v.26 no.A
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    • pp.199-205
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    • 2006
  • Ozone alone and catalytic ozone processes were introduced for treatment of humic acid, which is representative refractory organic compound. The treatment efficiencies of humic acid in each process were analyzed in pH variation, DOC removal, and $UV_{254}$ decrease. Mn loaded GAC catalyst was prepared by loading potassium permanganate onto the granular activated carbon surface. BCM-GAC and BCM-Silica gel catalyst were prepared by BCM. $UV_{254}$ decrease in all processes was comparatively high with efficiency over 87%. DOC removal in ozone/GAC process was the highest with 78%, and removal rates for other processes followed the order ozone/BCM-GAC(62%) > ozone/BCM-silica gel(45%) > ozone/silica gel(43%) > ozone/Mn Loaded GAC(42%) > ozone alone(37%).

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Enhancement of cis,cis-Muconate Productivity by Overexpression of Catechol 1,2-Dioxygenase in Pseudomonas putida BCM114

  • Kim, Beum-Jun;Park, Won-Jae;Lee, Eun-Yeol;Park, Cha-Yong
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.3 no.2
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    • pp.112-114
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    • 1998
  • For enhancement of cis,cis-muconate productivity from benzoate, catechol 1,2-dioxygenase (C12O) which catalyzes the rate-limiting step (catechol conversion to cis,cis-muconate) was cloned and expressed in recombinant Pseudomonas putida BCM114. At higher benzoate concentrations (more than 15 mM), cis,cis-muconate productivity gradually decreased and unconverted catechol was accumulated up to 10 mM in the cae of wild-type P. putida BM014, whereas cis,cis-muconate productivity continuously increased and catechol was completely transformed to cis,cis-muconate for P. putida BCM114. Specific C12O activity of P. putida BCM114 was about three times higher than that of P. putida BM014, and productivity was enhanced more than two times.

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The Effects of Breath-Counting Meditation and Deep Breathing on Heart Rate Variability

  • Kim, Ji-Hwan;Bae, Hyo-Sang;Park, Seong-Sik
    • The Journal of Korean Medicine
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    • v.37 no.2
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    • pp.36-44
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    • 2016
  • Objectives: This study aimed to evaluate the effects of breath-counting meditation (BCM) and deep breathing (DB) on heart rate variability (HRV). These breathing techniques have the characteristics of non-paced and self-controlled breathings, resulting in less increase of HRV. We also compared BCM and DB with usual breathing (UB) or relaxing breathing (RB) which can reveal the characteristics of those. Methods: 83 healthy volunteers sitting in chairs performed non-paced breathing; UB, RB, BCM, and DB each for 5 minutes. One minute of relaxation was permitted between breathings. Participants surfed the internet sitting in front of a computer during UB, while for RB, they remained steady with eyes closed. For BCM, they breathed inwardly counting from 1 to 10 repetitively, while they took a deep breath during DB. Physiological indices were simultaneously recorded with a biofeedback system. Results: Respiration rate, thoracic amplitude, and mean heart rate decreased in RB compared with UB, but there was no change in HRV. Respiration rate in BCM and DB was lower than that in UB or RB, and the amplitude of thorax or abdomen, and HRV all increased (p<0.05). However, mean heart rate and skin conductance decreased in BCM compared with UB (p<0.05), whereas those were no different between DB and UB. Conclusion: BCM, just concentrating mentally on breathing with counting each breath, can increase HRV with less sympathetic activation, while DB, actively moving thorax and abdomen for achieving the deepest respiration rate, can greatly raise HRV with the maintenance of mean vagal or sympathetic tone.