• Title/Summary/Keyword: 사용-확산

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Optimizated pH and Mitigated Ammonia Emission in Pig Manure Slurry by Soluble Carbohydrate Supplementation (수용성 탄수화물을 이용한 분뇨슬러리 pH 적정화 및 암모니아 휘산의 저감)

  • Lim, Joung-Soo;Hwang, Ok-Hwa;Lee, Sang Ryong;Cho, Sung-Back;Kwag, Jung-Hoon;Lee, Dong-Hyun;Jung, Min Woong;Han, Deug-Woo
    • Journal of the Korea Organic Resources Recycling Association
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    • v.25 no.1
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    • pp.103-110
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    • 2017
  • In Concentrated Animal Feeding Operations(CAFOs), emission of ammonia from stored manure contributes negatively on the wellness of livestock. In CAFOs facilities, indoor aerial ammonia concentration oftentime surpasses the critical level potentially harmful to livestock's immune system. Understandably, numerous researches to control aerial ammonia have been conducted in countries where CAFOs were practiced for many decades. Some innovative technologies, such as scrubber, bio-filter, and additives emerged, as a result. Among them, microbial additives became popular in Korea, due to an easiness of use and affordability. However, microbial additives still have some weaknesses. Their price is still high enough to discourage farmers who run a small scale farm and their effectiveness are still questioned by many users and researchers. In the present study, we found soluble carbohydrates, such as sugar, glucose, and molasses, when supplemented to pig slurry manure, can mitigate ammonia emission. To be more specific, pig manure slurry(120kg), stored in container(200L), was supplemented with sugar at 0.1%(w/w) and was, subsequently, monitored for pH and aerial ammonia for next 10 days. From this experiment, it was found that the sugar supplementation was effective in mitigating the aerial ammonia concentration (33% in average) when monitored daily. Also, the pH of manure slurry was maintained at relatively low level(8.2) in sugar-supplemented manure slurry while it was elevated to 8.5 in untreated slurry. Conclusively, the obtained data suggest that soluble carbohydrate can mitigate ammonia emission by acidifying manure slurry. Additionally, it can be suggested that soluble carbohydrates, such as sugar, glucose, and molasses, can be reasonable choices for animal farmers who have been looking for an alternative choice to replace expensive microbial additives.

Research of z-axis geometric dose efficiency in multi-detector computed tomography (MDCT 장치의 z-축 기하학적 선량효율에 관한 연구)

  • Kim, You-Hyun;Kim, Moon-Chan
    • Journal of radiological science and technology
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    • v.29 no.3
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    • pp.167-175
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    • 2006
  • With the recent prevalence of helical CT and multi-slice CT, which deliver higher radiation dose than conventional CT due to overbeaming effect in X-ray exposure and interpolation technique in image reconstruction. Although multi-detector and helical CT scanner provide a variety of opportunities for patient dose reduction, the potential risk for high radiation levels in CT examination can't be overemphasized in spite of acquiring more diagnostic information. So much more concerns is necessary about dose characteristics of CT scanner, especially dose efficient design as well as dose modulation software, because dose efficiency built into the scanner's design is probably the most important aspect of successful low dose clinical performance. This study was conducted to evaluate z-axis geometric dose efficiency in single detector CT and each level multi-detector CT, as well as to compare z-axis dose efficiency with change of technical scan parameters such as focal spot size of tube, beam collimation, detector combination, scan mode, pitch size, slice width and interval. The results obtained were as follows ; 1. SDCT was most highest and 4 MDCT was most lowest in z-axis geometric dose efficiency among SDCT, 4, 8, 16, 64 slice MDCT made by GE manufacture. 2. Small focal spot was 0.67-13.62% higher than large focal spot in z-axis geometric dose efficiency at MDCT. 3. Large beam collimation was 3.13-51.52% higher than small beam collimation in z-axis geometric dose efficiency at MDCT. 4. Z-axis geometric dose efficiency was same at 4 slice MDCT in all condition and 8 slice MDCT of large beam collimation with change of detector combination, but was changed irregularly at 8 slice MDCT of small beam collimation and 16 slice MDCT in all condition with change of detector combination. 5. There was no significant difference for z-axis geometric dose efficiency between conventional scan and helical scan, and with change of pitch factor, as well as change of slice width or interval for image reconstruction. As a conclusion, for reduction of patient radiation dose delivered from CT examination we are particularly concerned with dose efficiency of equipment and have to select proper scanning parameters which increase z-axis geometric dose efficiency within the range of preserving optimum clinical information in MDCT examination.

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Human Resource Management Policy for University Faculty enhancing University-Industry Cooperation (산업현장친화형 대학교원 인사제도의 방향)

  • Jang, Seungkwon;Choi, Jong-In;Hong, Kilpyo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.8 no.4
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    • pp.95-109
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    • 2013
  • The practices and processes of HRM (Human Resource Management) for university faculty in Korea depend heavily on assessment of research and teaching rather than the UIC (University-Industry Cooperation) performance. In this regard, HRM of Korean universities is said to be far distant from UIC. Although policy initiatives by the Korean government, notably the MoE (Ministry of Education) have implemented in most universities, the desirable level of UIC could not be achieved yet. Moreover, the very notion of 'university' in Korea is much more to do with 'pure' education and research institution than with 'applied' and 'vocational' purpose. Considering upon HRM practices and organizational culture, for enhancing UIC in Korea, the government's policy should be linked to alter deep-rooted university culture. So the aims of the research are to describe the current state of HRM in Korean and foreign universities; to find out the critical factors of UIC in Korean universities; to analyze the gaps between university research and industrial commercialization based on a conceptual framework, the 'valley of the death'; and to recommend HRM policies fostering UIC for the MoE. For achieving these objectives, we deploy multiple methodologies, namely, in-depth interview, literature survey, and statistical data analysis with regard to UIC. Analyzing the data we have collected, the present research sheds light on all aspects of HRM processes and UICs. And the main policy implication is restricted to the Korean universities, even if we have collected and analyzed foreign universities, notably universities in the USA. The research findings are mainly two folds. Firstly, the HRM practices among Korean universities are very similar due to the legally institutionalized framework and the government's regulations. Secondly, the difficulties of UIC can be explained by notion of the 'valley of death' ways in which both parties of university and industry are looking for different purposes and directions. In order to overcome the gap in the valley of death, the HRM policy is better to be considered as leverage. Finally, the policy recommendations are as follows. Firstly, various kinds of UIC programs are able to enhance the performances of not only UIC, but also education and research outcome. Secondly, fostering organizational climate and culture for UIC, employing various UIC programs, and hiring industry-experienced faculty are all very important for enhancing the high performance of university. We recommend the HRM policies fostering UIC by means of indirect way rather than funding directly for university. The HRM policy of indirect support is more likely to have long-term effectiveness while the government's direct intervention to UIC will have likely short-term effectiveness as the previous policy initiatives have shown. The MEST's policy means of indirect support might vary from financial incentives to the universities practicing HRM for UIC voluntarily, to information disclosure for UIC. The benefits of the present research can be found in suggesting HRM policy for UIC, highlighting the significance of industry-experienced faculty for UIC, and providing statistical analysis and evidences of UIC in Korean universities.

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Analysis of the 'Problem Solving and Invention' Units of Technology and Home Economics 1 Textbook (기술.가정 1 교과서 '문제해결과 발명' 단원 분석)

  • Jung, Jin Woo
    • 대한공업교육학회지
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    • v.38 no.1
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    • pp.49-67
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    • 2013
  • The purpose of this study is to analyze the external systems and the units 'problem solving and invention' of the middle school technology and home economics 1 textbooks of the revised 2011 national curriculum in an effort to provide some information on the content system of invention education in technology class, as invention education was provided as part of a regular subject for the first time. The findings of the study were as follows: First, 'Technology and Inventions' chapter of Technology and Home Economics 1 Textbooks occupied 10-18% share, with the subchapter of 'Problem Solving and Invention' unit taking up 6.7-29% of the textbooks. Second, for most textbooks, 'Technological Problem Solving', 'Idea Generation' 'Multi-dimensional Projection Method', 'Expansive Thought-Processing Methodology', 'Converging Thought Methodology' and 'Invention in Everyday Lives' were included as main contents based on the accomplishment criteria presented in education process interpretation documents. Third, the detailed structures were generally made up as follows: Introduction (Broad Chapter Title, Subchapter Table of Contents, Introduction, Subchapter Title, Study Objectives, Open Thinking); Development (Unit Title, Thinking Ahead, Core Terms, Main Text, Study Helper, Activities, Research Exercises, Supplemental Readings, In-depth Study Topics, Technology in Everyday Lives, Reading Topics, Discussion Topics, and Career Helpers); and Summary (Subchapter Summary, Study Summary, Terms Summary, Writing Follow-up, Self Review, Broad Chapter Evaluation). Fourth, based on the analysis of figures included, photographs had the largest share, followed by figures, tables, and graphs. The photos were used to illustrate various inventions, invention methodologies, and exercise activities, while figures were included to depict the contents included in the main text, and the tables to assist to preparation of process diagrams or materials lists. Fifth, based on the analysis of content weights, greater weights were placed on 'Inventions and Thoughts', and 'Invention Experiment Activities,' while 'Understanding Inventions' and 'Invention and Patents' chapters did not have a lot of texts involved. Sixth, based on the analysis of content presentation methods, most textbooks combined figures, tables, illustrations and texts to discuss the topics. Based on the above study results, we suggest the following: First, a consistent education curriculum should be developed over the topic of invention; and second, more precise and systematic analysis of textbooks would need to be performed.

Clinical and Bacteriologic Efficacy of Cefdinir on Pharyngitis and Pharyngotonsillitis Caused by Group A Beta Hemolytic Streptococci in Children (Group A-beta Hemolytic Streptococci에 의한 소아 인두편도염에 있어서 Cefdinir의 항균력과 임상적 및 세균학적 효과에 관한 연구)

  • Chung, Ji-Young;Sin, Seon-Hee;Ahn, Young-Min;Ahn, Byung-Moon;Sin, Young-Gyu;Bae, Young-Min;Park, Soo-Eun;Kim, Jong-Guk;Lee, Jong-Guk;Ma, Saung-Hyuk;Chang, Jin-Kun;Cha, Sung-Ho
    • Pediatric Infection and Vaccine
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    • v.10 no.1
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    • pp.95-101
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    • 2003
  • Objective : To determine the clinical and bacteriologic efficacy and safety of Cefdinir in acute pharyngitis and pharyngotonsillitis caused by group A beta hemolytic streptococci in pediatric patients. Methods : Children aged 3 through 12 years who visited the hospitals enrolled in this study with signs and symptoms of pharyngitis or pharyngotonsillitis since May to December 2002, were taken throat culture and given Cefdinir(12 mg/kg/day, in three divided doses) for 7 days. Two hundred thirty five patients were enrolled and 90 patients who showed positive culture results were followed up for the signs and symptoms during the treatment to determine clinical efficacy. Follow-up culture were done at the end of the study and bacteriologic efficacy was determined Results : Ninety out of 235 patients who visited the hospitals with the signs and symptoms of pharyngitis showed positive growth on throat culture. Seventy nine patients were clinically and microbiologically assessable. The bacteriologic eradication rates of S. pyogenes were 100% in all the children treated with Cefdinir. Clinical cure rates were not different between less than 7 days-treated group(75%) and just 7 days-treated group(98.6%)(P=0.077). Two patients reported adverse reaction during Cefdinir treatment. Antimicrobial sensitivity of Cefdinir against S. pyogenes was 100% with range of MIC being less than 0.5 ${\mu}g/mL$. Conclusion : It seems that Cefdinir is one of reliable and well-tolerated drugs for the treatment of group A beta hemolytic streptococcal pharyngotonsillitis in children. It needs to be investigated short term efficacy in terms of improving drug compliance and impact of economic point of view. We can recognized that still high rate of the erythromycin resistant group A streptococci in our community should be monitored every year.

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Environmental Assessment of the Shihwa Lake by using the Benthic Pollution Index (저서오염지수(BPI)를 이용한 시화호 환경평가)

  • Lee, Jae-Hac;Park, Ja-Yang;Lee, Hyung-Gon;Park, Heung-Sik;Kim, Dong-Sung
    • Ocean and Polar Research
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    • v.25 no.2
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    • pp.183-200
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    • 2003
  • In order to assess the ecological changes induced by organic pollutants of the Shihwa Lake, BPI (Benthic Pollution Index) based on the benthic faunal community was employed. It was modified from Infaunal Trophic Index (ITI), and recommended as a pollution detecting method for the environmental assessment. The BPI values were calculated from the benthos data, which were collected for three terms: in 1980, before the Shihwa Lake was built up; in 1994-1997, which the Shihwa Lake was completely isolated from the outer seawater; in 1997-1999, after inflow of the outer seawater. Since the Shihwa Dike was constructed in February 1994, the pollution intensity of the lake had been increased from the narrow and inner part of the former Gyeonggi Bay and spread fast along the coast line of the Shihwa Lake. Then, in 1996 it showed the very high BPI levels all around the Lake. This serious polluted condition had been lasted till 1997, when the inflow of the seawater was begun. In 1998, from the nearest part of the Shihwa Gate, the BPI levels gradually became low in most area of the Lake, except its inner and narrow part. These greatly lowered BPI levels mean that the seawater inflow could be assumed to affect positively in the lake. Furthermore, BPI gave the same results from the other environmental assessment based on the abundance and the species richness of macrobenthic community. It shows that BPI could be useful as an effective method to assess the marine environment and evaluate the status of environmental conditions.

Material Characteristics and Provenance Presumption for Stone Artifacts of Bronze Age from the Hyocheon Site in Gwangju, Korea (광주 효천유적 출토 청동기시대 석기의 재질특성과 원산지 추정)

  • Park, Sung-Mi;Lee, Chan-Hee;Kim, Ji-Young;Jeong, Il
    • Journal of Conservation Science
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    • v.21
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    • pp.5-20
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    • 2007
  • The stone artifacts in Bronze age from the Hyocheon sites in the Gwangju, Korea were studied on the basis of material characteristics and provenance presumptions. The use and rock names of the artifacts are a stone shovel by andesite, the stone grinding pestle by pyrophyllite, the stone sickle by schist and four stone semifinished artifacts by slates. Andesitic stone shovel could be observed easily around the Hyocheon relic site. But, rocks of the stone grinding pestle, the stone sickle, the stone arrowhead and the stone semifinished artifacts could be confirmed typical occurrences of the all kinds of rocks around the Hwasun coal mine area above 10km from the site. These are made the coupled samples with each stone artifact to the same kinds of raw material rocks based on analysis of the lithology and geochemistry. As a result a geochemical evolution trends of both a stone artifact and the rock showed very similar patterns based on normalization using the behavior, enrichment, compatibility and incompatibility of the elements. Therefore, the source rock of the stone shovel was convey from Mudeung mountain possible interpreted that the domestic-type artifacts are distributed in the vicinity of the Hyocheon site. On the other hand, the stone grinding pestle, the stone sickle, the stone arrowhead and the stone semifinished artifacts were convey from the Hwasun coal mine area possible foreign-type stone artifacts interpreted that the source rocks. Consequently, in the foreign-type stone artifacts are should archaeologic research which it can examine various possibilities clearly that the possibility to coming the introduction with the mankind migration, diffusion to dealings of tribe, the captured enemy equipment through the war and the trade with the behavior of the materials.

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Prevalence of CTX-M-type Extended-Spectrum $\beta$-Lactamases Producing Escherichia coli and Klebsieilla pneumoniae Isolates in General Hospitals in 2005 (임상에서 분리된 CTX-M형 Extended-Spectrum $\beta$-Lactamases를 생산하는 Escherichia coli와 Klebsiella pneumoniae의 유행)

  • Kim, Yun-Tae;Kim, Tae-Un
    • Microbiology and Biotechnology Letters
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    • v.34 no.4
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    • pp.342-351
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    • 2006
  • The aim of this study was to survey susceptibilities of Escherichia coli and Klebsiella pneumoniae isolates against cefotaxime and to determine the prevalences of CTX-M type extended-spectrum $\beta$-lactamases (ESBLs) producing E. coli and K. pneumoniae in Korea. During the period of February to July, 2005, 153 E. coli and 52 K. neumoniae isolates were collected from 2 hospitals in Busan. Antimicrobial susceptibilities to cefotaxime were tested by the disk diffusion method. ESBL production of E. coli and K. pneumoniae was determined by the double disk synergy test. MICs of $\beta$-lactam antibiotics were determined by the agar dilution method. Blac$_{CTX-M}$ genes of the organism were detected by PCR. Among 153 isolates of E. coli and 52 isolates of K. neumoniae, 27 (17.6%) and 25 (48.0%) were intermediate or resistant to cefotaxime, respectively. Twenty-three (15.0%) isolates out of 153 E. coli and 13 (25.0%) out of 52 K. neumoniae isolates showed positive results for ESBL by the double disk synergy test. Twenty isolates out of 23 ESBL producing E. coli and 12 out of 13 ESBL producing K. neumoniae isolates harbored biacTx-M gene,11 of ESBL producing E. coli and 12 of ESBL producing K. neuinoniae isolates harbored bla$_{CTX-M}$ gene, 11 of the ESBL producing E. coli and 2 of ESBL producing K. neumoniae isolates harbored bla$_{TEM}$ gene, and 1 of the ESBL producing E. coli and 12 of ESBL producing K. neumoniae isolates harbored bla$_{SHV}$ gene. E. coli and K. neumoniae isolates producing CTX-M-type ESBLs were not uncommon in Korea. It is thought that continuous survey are necessary for inspecting the spread and novel variants of CTX-M-type ESBL genes. Further me]'e investigation and research on ESBL producing strains are needed in order to prevent the spread of resistant bacteria.

Heterogeneous Oxidation of Liquid-phase TCE over $CoO_x/TiO_2$ Catalysts (액상 TCE 제거반응을 위한 $CoO_x/TiO_2$ 촉매)

  • Kim, Moon-Hyeon;Choo, Kwang-Ho
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.3
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    • pp.253-261
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    • 2005
  • Catalytic wet oxidation of ppm levels of trichloroethylene (TCE) in water has been conducted using $TiO_2$-supported cobalt oxides at a given temperature and weight hourly space velocity. 5% $CoO_x/TiO_2$ might be the most promising catalyst for the wet oxidation at $36^{\circ}C$ although it exhibited a transient behavior in time on-stream activity. Not only could the bare support be inactive for the wet decomposition reaction, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Characterization of the $CoO_x$ catalyst by acquiring XPS spectra of both fresh and used Co surfaces gave different surface spectral features of each $CoO_x$. Co $2p_{3/2}$ binding energy of Co species exposed predominantly onto the outermost surface of the fresh catalyst appeared at 781.3 eV, which is very similar to the chemical states of $CoTiO_x$ such as $Co_2TiO_4$ and $CoTiO_3$. The spent catalyst possessed a 780.3 eV main peak with a satellite structure at 795.8 eV. Based on XPS spectra of reference Co compound, the TCE-exposed Co surfaces could be assigned to be in the form of mainly $Co_3O_4$. XRD measurements indicated that the phase structure of Co species in 5% $CoO_x/TiO_2$ catalyst even before reaction is quite comparable to the diffraction lines of external $Co_3O_4$ standard. A model structure of $CoO_x$ present on titania surfaces would be $Co_3O_4$, encapsulated in thin-film $CoTiO_x$ species consisting of $Co_2TiO_4$ and $CoTiO_3$, which may be active for the decomposition of TCE in a flow of water.

Characteristics of Hydrodynamics, Heat and Mass Transfer in Three-Phase Inverse Fluidized Beds (삼상 역 유동층의 수력학, 열전달 및 물질전달 특성)

  • Kang, Yong;Lee, Kyung Il;Shin, Ik Sang;Son, Sung Mo;Kim, Sang Done;Jung, Heon
    • Korean Chemical Engineering Research
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    • v.46 no.3
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    • pp.451-464
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    • 2008
  • Three-phase inverse fluidized bed has been widely adopted with its increasing demand in the fields of bioreactor, fermentation process, wastewater treatment process, absorption and adsorption processes, where the fluidized or suspended particles are small or lower density comparing with that of continuous liquid phase, since the particles are frequently substrate, contacting medium or catalyst carrier. However, there has been little attention on the three-phase inverse fluidized beds even on the hydrodynamics. Needless to say, the information on the hydrodynamics and transport phenomena such as heat and mass transfer in the inverse fluidized beds has been essential for the operation, design and scale-up of various reactors and processes which are employing the three-phase inverse beds. In the present article, thus, the information on the three-phase inverse fluidized beds has been summarized and reorganized to suggest a pre-requisite knowledge for the field work in a sense of engineering point of view. The article is composed of three parts; hydrodynamics, heat and mass transfer characteristics of three-phase inverse fluidized beds. Effects of operating variables on the phase holdup, bubble properties and particle fluctuating frequency and dispersion were discussed in the section of hydrodynamics; effects of operating variables on the heat transfer coefficient and on the heat transfer model were discussed in the section of heat transfer characteristics ; and in the section of mass transfer characteristics, effects of operating variables on the liquid axial dispersion and volumetric liquid phase mass transfer coefficient were examined. In each section, correlations to predict the hydrodynamic characteristics such as minimum fluidization velocity, phase holdup, bubble properties and particle fluctuating frequency and dispersion and heat and mass transfer coefficients were suggested. And finally suggestions have been made for the future study for the application of three-phase inverse fluidized bed in several available fields to meet the increasing demands of this system.