• Clean Technology
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• v.26 no.2
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• pp.102-108
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• 2020

In recent years, packed column has been widely used in separation processes, such as absorption, desorption, distillation, and extraction, in the petrochemical, fine chemistry, and environmental industries. Packed column is used as a contacting facility for gas-liquid and liquid-liquid systems filled with random packed materials in the column. Packed column has various advantages such as low pressure drop, economical efficiency, thermally sensitive liquids, easy repairing restoration, and noxious gas treatment. The performance of a packed column is highly dependent on the maintenance of good gas and liquid distribution throughout a packed bed; thus, this is an important consideration in a design of packed column. In this study, hydraulic pressure drop, hold-up as a function of liquid load, and mass transfer in the air, air/water, and air-NH₃/water systems were studied to find the geometrical characteristic for raschig super-ring experiment dry pressure drop. Based on the results, design factors and operating conditions to handle noxious gases were obtained. The dry pressure drop of the random packing raschig super-ring was linearly increased as a function of gas capacity factor with various liquid loads in the Air/Water system. This result is lower than that of 35 mm Pall-ring, which is most commonly used in the industrial field. Also, it can be found that the hydraulic pressure drop of raschig super-ring is consistently increased by gas capacity factor with various liquid loads. When gas capacity factor with various liquid loads is increased from 1.855 to 2.323 kg^-1/2 m^-1/2 S^-1, hydraulic pressure drop increases around 17%. Finally, the liquid hold-up related to packing volume, which is a parameter of specific liquid load depending on gas capacity factor, shows consistent increase by around 3.84 kg^-1/2 m^-1/2 S^-1 of the gas capacity factor. However, liquid hold-up significantly increases above it.

• Journal of Ginseng Research
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• v.32 no.3
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• pp.179-186
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• 2008

Effect of pulverization on total solid, crude saponin, and acidic polysaccharide contents of dried red ginseng main root were tested. Several particle size samples, including red ginseng main root (non pulverized), $10{\sim}40$ mesh powder, $40{\sim}100$ mesh powder, and >100 mesh powder were used in the extraction. The sequential solvent extraction method (1st: 70% EtOH at $70^{\circ}C$ for 12 hr, 2nd: 70% EtOH at $70^{\circ}C$ for 12 hr, 3rd: water at $70^{\circ}C$ for 12 hr) was applied to extract the saponins and acidic polysaccharide. Extraction yield of total solid of pulverized red ginseng ($10{\sim}40$ mesh size) was increased to 20% compared with that of non-pulverized. Especially, the crude saponin content of pulverized red ginseng ($10{\sim}40$ mesh size) showed an increase of 47% over non-pulverized. No difference in the component ratio was observed by pulverization, when the individual ginsenosides were quantified by HPLC. Also, extraction yield of acidic polysaccharide of pulverized red ginseng ($10{\sim}40$ mesh size) was increased 57% compared with that of non-pulverized. The results suggested that pulverization might be useful for increasing the extraction yield of red ginseng components.

• Journal of Dairy Science and Biotechnology
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• v.33 no.2
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• pp.111-118
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• 2015

Probiotic, prebiotic, and synbiotic substances as well as microorganisms were added to infant formula in an attempt to influence the intestinal microflora with an aim to stimulate the growth of lactic acid bacteria, especially bifidobacteria and lactobacilli. Over the last 10 years, new synbiotic infant formulas containing probiotics and prebiotics have been proposed in order to simulate the effect of breast-feeding on the intestinal microflora. Owing to their synergistic effect, the new synbiotics are expected to be more helpful than using probiotics and prebiotics individually. Maintenance of the viability of the probiotics during food processing and the passage through the gastrointestinal tract should be the most important consideration, since a sufficient number of bacteria ($10^8cfu/g$) should reach the intended location to have a positive effect on the host. Storage conditions and the processing technology used for the manufacture of products such as infant formula adversely affect the viability of the probiotics. When an appropriate and cost-effective microencapsulation methodology using the generally recognized as safe (GRAS) status and substances with high biological value are developed, the quality of infant formulas would improve. The effect of probiotics may be called a double-effect, where one is an immunomodulatory effect, induced by live probiotics that advantageously alter the gastrointestinal microflora, and the other comprises anti-inflammatory responses elicited by dead cells. At present, a new terminology is required to define the dead microorganisms or crude microbial fractions that positively affect health. The term "paraprobiotics" (or ghost probiotics) has been proposed to define dead microbial cells (not damaged or broken) or crude cell extracts (i.e., cell extracts with complex chemical composition) that are beneficial to humans and animals when a sufficient amount is orally or topically administered. The fecal microflora of bottle-fed infants is altered when the milk-based infant formula is supplemented with probiotics or prebiotics. Thus, by increasing the proportion of beneficial bacteria such as bifidobacteria and lactobacilli, prebiotics modify the fecal microbial composition and accordingly regulate the activity of the immune system. Therefore, considerable attention has been focused on the improvement of infant formula quality such that its beneficial effects are comparable to those of human milk, using prebiotics such as inulin and oligosaccharides and potential specific probiotics such as bifidobacteria, which selectively stimulate the proliferation of beneficial bacteria in the microflora and the indigenous intestinal metabolic activity of the microflora.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.797-806
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• 2000

The objectives were to compare the biodegradable threshold concentrations of phenol with the different composition of the influent carbon source and examine the SMA (Specific Methanogenic Activity)and the possibility of simultaneous removal of high-strength organics and nitrogen compounds in UASB(Upflow Anaerobic Sludge Blanket) - PBR(Packed Bed Reactor) process. The results showed that UASB reactors were efficient to remove phenol and phenol + glucose from synthetic wastewater. At phenol conc, of 600 mg/L and SCOD conc. of 2100 mg/L in UASB reactor(with only phenol as substrate), the removal efficiencies of phenol and SCOD were over 99% and 93% respectively, under MLVSS of 20 g. The activity of microorganism was $0.112g\;phenol/g\;VSS{\cdot}d$, $0.351g\;SCOD/g\;VSS{\cdot}d$. The gas production rate was $0.115L/g\;VSS{\cdot}d$ and $CH_4$ content in gas was about 70%. At phenol conc. of 760 mg/L and SCOD conc. of 4300 mg/L in UASB reactor( with phenol + glucose as substrates), the removal efficiencies of phenol and of SCOD were over 99% and 90% respectively, under MLVSS of 20 g. The activity of microoganism was $0.135g\;phenol/g\;VSS{\cdot}d$, $0.696g\;SCOD/g\;VSS{\cdot}d$. The gas production rate was $0.257L/g\;VSS{\cdot}d$ and $CH_4$ content in gas was about 70%. Serum bottle test showed that the activity of granule was inhibited over 1600 mg/L phenol conc, and denitrification and methanogenesis simultaneously took place in UASB granules under co-substrates conditions. PBR reactor packed with cilium type media, was efficient in nitrification. In condition of $0.038kg\;NH_4-N/m^3-media{\cdot}d$. 10~12 mg/L phenol conc. and 200~500 mg/L SCOD conc., nitrification efficiency was over 90% and phenol removal efficiency was over 98%.

• Proceedings of The Korean Society of Health Promotion Conference
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• 2005.09a
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• pp.91-119
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• 2005

오타와 헌장에 따르면 건강증진은 건강형평성을 성취하는 것이다. 건강격차를 감소시키고, 모든 사람들이 건강잠재력을 달성할 수 있도록 동등한 기회와 자원이 제공되어야 한다. 또한 각 개인들은 자신의 건강에 대한 결정요인들에 대한 통제능력을 가져야 한다. 미국의 조기사망은 40%가 행동양식에 의하여, 30%가 유전적인 문제로, 15%가 사회적 환경에 의하여, 10%는 의료적 치료의 부족으로, 그리고 5%는 환경위해 물질에 대한 노출로 발생한다. 건강불평등을 발설시키는 사회적 요인으로는 경제적 요인을 들 수 있다. 이러한 요인으로 야기되는 건강불평등의 문제를 해결하여 건강형평성을 달성하기 위해서는 절대적 목표들과 평등관련 목표들이 모두 필요하다. 건강형평성은 인구집단의 건강과 함께 향상되는 것으로 나은 건강상태에 있는 사람들의 건강을 악화시키면서 건강형평성을 달성하는 것은 아니다. 각자의 관심이 형평성을 어떻게 규정하는가에 영향을 미친다. 혜택을 받은 사람들은 성과/투입의 정의를 선호하며, 소외계층은 똑같은 성과 또는 요구에 기반한 정의를 선호한다. Healthy People 2010은 미국의 국가적 예방체계를 의미하며, 가장 중요하며 예방 가능한 건강위협들을 파악하고 이러한 위협들을 감소하기 위한 목적들이 설정되어 있다. 궁극적인 목적은 건강한 삶의 질적인 면과 양적인 측면을 향상시키는 것이며, 건강불평등을 제거하는 것이다. 그러나 미국이 유럽의 국가들에 비해서 사회 프로그램에 대한 투자가 적은 이유는 재분배는 소수인종만을 위한 것이라는 믿음과, 우리는 개방되고 공정한 사회에 살고 있기 때문에 가난하다는 것은 가난한 사람들 자신들의 잘못으로 인한 것이라는 믿음 그리고 재분배를 방지하는 정치체계 때문이다. 국가기관인 CDC의 예방연구센터(Prevention Research Centers)는 지역사회 파트너들과 함께 건강증진, 질병예방, 그리고 질병과 상해로 인한 합병증을 관리하게 위한 효과적인 예방 전략을 개발하고 있다. 예방연구센터의 프로그램들은 지역사회 기반 참여연구와 소외된 계층에 중점을 두며, 다학제 간 접근방법을 활용하고, 교육기관, 공공보건기관 그리고 지역사회의 파트너들 간의 네트웍을 형성을 통한 협력관계를 강조하고 있다. 지역사회 위원회가 구성되어 있으며, 또한 근거중심 프로그램을 개발하고 있다. 이들은 건강 결정요인에 관한 연구, 형성적 연구, 개입 프로그램 및 프로그램의 확산에 관한 연구를 진행한다. UC Berkeley의 가족/지역사회 보건센터(Center for Family & Community Health)는 1993년에 설립되었다. 사업의 대상이 되는 주요 지역사회는 한국교민사회이며, 한국교민사회 자문위원회(Korean Community Advisory Board, KCAB)가 구성되어 있다. 1993년부터 2003년까지는 'Health is Strength' 사업이 시범연구사업으로 진행되었는데, 그 내용은 유방암과 자궁경부암 검진 프로그램이었다. 2003년부터 2009년까지 진행될 'Quitting is Winning'이라는 두 번째 시범연구사업은 남성들의 금연에 중점을 둔 사업이다. 'Health is Strength'는 아시아 보건서비스 및 한국교민사회 자문위원회가 함께 협력하여 진행된 사업으로, 주요 목표는 18세 이상 여성의 자궁암 조기 검진(Pap test)과 자가 유방검진 실천을 증가시키는 것이며, 50세 이상여성의 유방 임상검사와 유방 X선촬영 비율을 증가시키는 것이었다. 한 지역의 카운티에 거주하는 한국 여성들은 4년간의 개입프로그램의 대상이 되었으며, 이들을 대상으로 횡단적인 전화조사를 3번(사전, 중간, 사후)실시하였다. 개입 프로그램은 교회에서 워크샵 개최, Tell-A-Friend Form 작성하기, 포스터 및 책자 발행, 신문광고 등과 함께 자궁암 조기 검진(Pap test)과 유방 X선 촬영권을 무료로 제공하는 것으로 구성되었다. 'Quitting is Winning'은 지역사회 기반 참여 연구모형으로 한국교민사회 자문위원회는 흡연을 1순위의 사업으로 선정하였고, 근거에 기반한 금연 프로그램에 대한 연구들을 검토하여, 기존의 보편적 방법이 아닌 인터넷을 활용하는 프로그램을 진행하는 것으로 결정되었다. 이는 무작위 임상실험으로 연구대상으로 미국에 거주하는 한국인 남성흡연자 2300명을 모집하였다. 이들의 1/2은 실험군인 인터넷 프로그램 집단에, 또 다른 1/2은 대조군인 인쇄책자 집단에 무작위 할당되었다. 12개월 동안 11번의 진단이 인터넷을 통하여 진행되었으며, 참여와 참여유지에 대한 금전적인 보상이 제공되었다.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.29-40
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• 2005

According as base of digital hologram has been magnified, discussion of compression technology is expected as a international standard which defines the compression technique of 3D image and video has been progressed in form of 3DAV which is a part of MPEG. As we can identify in case of 3DAV, the coding technique has high possibility to be formed into the hybrid type which is a merged, refined, or mixid with the various previous technique. Therefore, we wish to present the relationship between various image/video coding techniques and digital hologram In this paper, we propose an efficient coding method of digital hologram using standard compression tools for video and image. At first, we convert fringe patterns into video data using a principle of CGH(Computer Generated Hologram), and then encode it. In this research, we propose a compression algorithm is made up of various method such as pre-processing for transform, local segmentation with global information of object image, frequency transform for coding, scanning to make fringe to video stream, classification of coefficients, and hybrid video coding. Finally the proposed hybrid compression algorithm is all of these methods. The tool for still image coding is JPEG2000, and the toots for video coding include various international compression algorithm such as MPEG-2, MPEG-4, and H.264 and various lossless compression algorithm. The proposed algorithm illustrated that it have better properties for reconstruction than the previous researches on far greater compression rate above from four times to eight times as much. Therefore we expect that the proposed technique for digital hologram coding is to be a good preceding research.

• Clean Technology
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• v.20 no.4
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• pp.375-382
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• 2014

This work investigated the plasma-catalytic decomposition of isopropyl alcohol (IPA) and the behavior of the byproduct compounds over monolith-supported metal oxide catalysts. Iron oxide ($Fe_2O_3$) or copper oxide (CuO) was loaded on a monolithic porous ${\alpha}-Al_2O_3$ support, which was placed inside the coaxial electrodes of plasma reactor. The IPA decomposition efficiency itself hardly depended on the presence and type of metal oxides because the rate of plasma-induced decomposition was so fast, but the behavior of byproduct formation was largely affected by them. The concentrations of the unwanted byproducts, including acetone, formaldehyde, acetaldehyde, methane, carbon monoxide, etc., were in order of $Fe_2O_3/{\alpha}-Al_2O_3$ < $CuO/{\alpha}-Al_2O_3$ < ${\alpha}-Al_2O_3$ from low to high. Under the condition (flow rate: $1L\;min^{-1}$; IPA concentration: 5,000 ppm; $O_2$ content: 10%; discharge power: 47 W), the selectivity towards $CO_2$ was about 40, 80 and 95% for ${\alpha}-Al_2O_3$, $CuO/{\alpha}-Al_2O_3$ and $Fe_2O_3/{\alpha}-Al_2O_3$, respectively, indicating that $Fe_2O_3/{\alpha}-Al_2O_3$ is the most effective for plasma-catalytic oxidation of IPA. Unlike plasma-alone processes in which tar-like products formed from volatile organic compounds are deposited, the present plasma-catalyst hybrid system did not exhibit such a phenomenon, thus retaining the original catalytic activity.

• Clean Technology
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• v.20 no.2
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• pp.189-201
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• 2014

Partial oxidation, $CO_2$ reforming and the oxidative $CO_2$ reforming of $CH_4$ to produce synthesis gas over supported Ni hydrotalcite-type ($Ni_{0.5}Ca_{2.5}Al$ catalyst) catalysts were carried out and the effects of metal supports (i.e.; Mg and Ca) on the formation of a stable double-layer structure on the catalysts were evaluated. The $CH_4$ reforming stability was determined to be affected by the differences in the interaction strength between the active Ni ions and support metal ions. Only a Ni-Mg-Al composition produced a highly stable hydrotalcite-type double-layered structure; while the Ni-Ca-Al-type composition did not. Such structure provides excellent stability for the catalyst (-80% efficiency) as confirmed by the long-term $CO_2$ reforming test (-100 h), while the Ni-Ca-Al catalyst exhibited deactivation phases starting at the beginning of the reaction. The interaction strength between the active metal (Ni) and the supporting components (Mg and Al) was determined by temperature-programed reduction (TPR) analyses. The affinity was also confirmed by the TPR temperature because the Ni-Mg-Al catalyst required a higher temperature to reduce the Ni relative to the Ni-Ca-Al catalyst. The highest initial activity for synthesis gas production was observed for the $Ni_{0.5}Ca_{2.5}Al$ catalyst; however, this activity decreased quickly due to coke formation. The $Ni_{0.5}Ca_{2.5}Al$ catalyst exhibited a high reactivity and was more stable than the other catalysts because it had a higher resistance to coke formation.

• Membrane Journal
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• v.19 no.4
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• pp.317-323
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• 2009

In this study the nanofiltration (NF) membrane treatment of a nitric acid waste solutions containing $Pb^{+2}$ heavy metal ion discharging from the etching processes of an electronics and semiconductors industry has been studied for the purpose of recycling of nitric acid etching solutions. Three kinds of NF membranes (General Electric Co. Duraslick NF-4040 membrane, Dow Co. Filmtec LP-4040 membrane and Koch Co. SelRO MPS-34 4040 membrane) were tested for their separation efficiency (total rejection) of $Pb^{+2}$ ion and membrane stability in nitric acid solution. NF experiments were carried out with a dead-end membrane filtration laboratory system. The membrane permeate flux was increased with the increasing storage time in nitric acid solution and lowering pH of acid solution because of the enhancing of NF membrane damage by nitric acid. The membrane stability in nitric acid solution was more superior in the order of Filmtec LP-4040 < Duraslick NF-4040 < SelRO MPS-34 4040 membrane. The total rejection of Pb+2 ion was decreased with the increasing storage time in nitric acid solution and lowering the pH of acid solution. The total rejection of $Pb^{+2}$ ion after 4 months NF treatment was decreased from 95% initial value to 20% in the case of Duraslick NF-4040 membrane, from 85% initial value to 65% in the case of SelRO MPS-34 4040 membrane and from 90% initial value to 10% in the case of Filmtec LP-4040 membrane. These results showed that SelRO MPS-34 4040 NF membrane was more suitable for the treatment of an acidic etching waste solutions containing heavy metal ions.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.1
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• pp.39-46
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• 2011

NO oxidation is an important prerequisite step to assist the selective catalytic reduction (SCR) at low temperatures ($<200^{\circ}C$). Therefore, we conducted the lab- and bench-scales experiments appling the sodium chlorite powder ($NaClO_2(s)$) for the oxidation of NO to $NO_2$ and the carbon-based catalyst for the reduction of $NO_x$ and $SO_2$; the lab- and bench-scales experiments were conducted in laboratory and iron-ore sintering plant, respectively. In the lab-scale experiment, known concentrations of $NO_x$ (200 ppm), $SO_2$ (75 ppm), $H_2O$ (10%) and $NH_3$ (400 ppm) in 2.6 L/min were introduced into a packed-bed reactor containing $NaClO_2(s)$, then gases produced by the reaction with $NaClO_2(s)$ were fed into the carbon-based catalyst (space velocity = $2,000hr^{-1}$) at $130^{\circ}C$. In the bench-scale experiment, flue gases of $50Nm^3/hr$ containing 120 ppm NO and 150 ppm $SO_2$ were taken out from the duct of iron-ore sintering plant, then introduced into the flow reactor; $NaClO_2(s)$ were injected into the flow reactor using a screw feeder. Gases produced by the reaction with $NaClO_2(s)$ were introduced into the carbon-based catalyst (space velocity = $1,000hr^{-1}$). Results have shown that, in both lab- and bench-scales experiments, NO was oxidized to $NO_2$ by $NaClO_2(s)$. In addition, above 90% of $NO_x$ and $SO_2$ removal were obtained at the carbon-based catalyst. These results lead us to suggest that the combination of $NaClO_2(s)$ with the carbon-based catalyst has the potential to achieve the simultaneous removal of $NO_x$ and $SO_2$ at low temperature ($<200^{\circ}C$).