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A Study on Fuel Quality Characteristics of F-T Diesel for Production of BTL Diesel (BTL 디젤 생산을 위한 F-T 디젤의 연료적 특성 연구)

  • Kim, Jae-Kon;Jeon, Cheol-Hwan;Yim, Eui-Soon;Jung, Choong-Sub;Lee, Sang-Bong;Lee, Yun-Je;Kang, Myung-Jin
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.3
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    • pp.450-458
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    • 2012
  • In order to reduce the effects of greenhouse gas (GHG) emissions, the South Korean government has announced a special platform of technologies as part of an effort to minimize global climate change. To further this effort, the Korean government has pledged to increase low-carbon and carbon neutral resources for biofuel derived from biomass to replace fossil and to decrease levels of carbon dioxide. In general, second generation biofuel produced form woody biomass is expected to be an effective avenue for reducing fossil fuel consumption and greenhouse gas (GHG) emissions in road transport. It is important that under the new Korean initiative, pilot scale studies evolve practices to produce biomass-to-liquid (BTL) fuel. This study reports the quality characteristics of F-T(Fischer-Tropsch) diesel for production of BTL fuel. Synthetic F-Tdiesel fuel can be used in automotive diesel engines, pure or blended with automotive diesel, due to its similar physical properties to diesel. F-T diesel fuel was synthesized by Fischer-Tropsch (F-T) process with syngas($H_2$/CO), Fe basedcatalyst in low temperature condition($240^{\circ}C$). Synthetic F-T diesel with diesel compositions after distillation process is consisted of $C_{12}{\sim}C_{23+}$ mixture as a kerosine, diesel compositions of n-paraffin and iso-paraffin compounds. Synthetic F-T diesel investigated a very high cetane number, low aromatic composition and sulfur free level compared to automotive diesel. Synthetic F-T diesel also show The wear scar of synthetic F-T diesel show poor lubricity due to low content of sulfur and aromatic compounds compared to automotive diesel.

A Study on Construction and Application of Nuclear Grade ESF ACS Simulator (원자력등급 ESF 공기정화계통 시뮬레이터 제작 및 활용에 관한 연구)

  • Lee, Sook-Kyung;Kim, Kwang-Sin;Sohn, Soon-Hwan;Song, Kyu-Min;Lee, Kei-Woo;Park, Jeong-Seo;Hong, Soon-Joon;Kang, Sun-Haeng
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.4
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    • pp.319-327
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    • 2010
  • A nuclear plant ESF ACS simulator was designed, built, and verified to perform experiment related to ESF ACS of nuclear power plants. The dimension of 3D CAD model was based on drawings of the main control room(MCR) of Yonggwang units 5 and 6. The CFD analysis was performed based on the measurement of the actual flow rate of ESF ACS. The air flowing in ACS was assumed to have $30^{\circ}C$ and uniform flow. The flow rate across the HEPA filter was estimated to be 1.83 m/s based on the MCR ACS flow rate of 12,986 CFM and HEPA filter area of 9 filters having effective area of $610{\times}610mm^2$ each. When MCR ACS was modeled, air flow blocking filter frames were considered for better simulation of the real ACS. In CFD analysis, the air flow rate in the lower part of the active carbon adsorber was simulated separately at higher than 7 m/s to reflect the measured value of 8 m/s. Through the CFD analyses of the ACSes of fuel building emergency ventilation system, emergency core cooling system equipment room ventilation cleanup system, it was confirmed that all three EFS ACSes can be simulated by controlling the flow rate of the simulator. After the CFD analysis, the simulator was built in nuclear grade and its reliability was verified through air flow distribution tests before it was used in main tests. The verification result showed that distribution of the internal flow was uniform except near the filter frames when medium filter was installed. The simulator was used in the tests to confirm the revised contents in Reg. Guide 1.52 (Rev. 3).

Nutrient Recovery from Sludge Fermentation Effluent in Upflow Phosphate Crystallization Process (상향류 인 결정화공정을 이용한 슬러지 발효 유출수로 부터의 영양소 회수)

  • Ahn, Young-Ho
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.8
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    • pp.866-871
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    • 2006
  • The nutrient recovery in phosphate crystallization process was investigated by using laboratory scale uptlow reactors, adopting sequencing batch type configuration. The industrial waste lime was used as potential cation source with magnesium salt($MgCl_2$) as control. The research was focused on its successful application in a novel integrated sludge treatment process, which is comprised of a high performance fermenter followed by a crystallization reactor. In the struvite precipitation test using synthetic wastewater first, which has the similar characteristics with the real fermentation effluent, the considerable nutrient removal(about 60%) in both ammonia and phosphate was observed within $0.5{\sim}1$ hr of retention time. The results also revealed that a minor amount(<5%) of ammonia stripping naturally occurred due to the alkaline(pH 9) characteristic in feed substrate. Stripping of $CO_2$ by air did not increase the struvite precipitation rate but it led to increased ammonia removal. In the second experiment using the fermentation effluent, the optimal dosage of magnesium salt for struvite precipitation was 0.86 g Mg $g^{-1}$ P, similar to the mass ratio of the struvite. The optimal dosage of waste lime was 0.3 g $L^{-1}$, resulting in 80% of $NH_4-N$ and 41% of $PO_4-P$ removal, at about 3 hrs of retention time. In the microscopic analysis, amorphous crystals were mainly observed in the settled solids with waste lime but prism-like crystals were observed with magnesium salt. Based on mass balance analysis for an integrated sludge treatment process(fermenter followed by crystallization reactor) for full-scale application(treatment capacity Q=158,880 $m^3\;d^{-1}$), nutrient recycle loading from the crystallization reactor effluent to the main liquid stream would be significantly reduced(0.13 g N and 0.19 g P per $m^3$ of wastewater, respectively). The results of the experiment reveal therefore that the reuse of waste lime, already an industrial waste, in a nutrient recovery system has various advantages such as higher economical benefits and sustainable treatment of the industrial waste.

Novel Gap Junction Molecules, Connexin 37, Enhances the Bystander Effect in HSVtk/GCV Gene Therapy (Herpes Simplex Virus thymidine Kinase/Ganciclovir 유전자 치료에서 새로운 간격결합분자 Connexin 37에 의한 방관자 효과의 증가)

  • Kim, Sun Young;Yi, Ho Keun;Lee, Jung Chang;Hwang, Dong Jin;Hwang, Pyoung Han;Lee, Dae Yeol;Cho, Soo Chul
    • Clinical and Experimental Pediatrics
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    • v.46 no.6
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    • pp.541-547
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    • 2003
  • Purpose : Gap junction intercellular communication(GJIC) is an important mechanism of the bystander effect in herpes simplex thymidine kinase/ganciclovir(HSVtk/GCV) gene therapy Therefore, we attempted to enhance the bystander effect in vitro by exogenous overexpressing connexin 37(Cx37) in cells to increase GJIC. Methods : NIH3T3 cells were transfected with the Cx37 and HSVtk gene or the HSVtk gene alone by the calcium phosphate method, and we detected their expression from these cells by RT-PCR. GCV-mediated cytotoxicity and the bystander effect of each transfectant was then assessed and compared. Results : Cells transfected with HSVtk became sensitive to low concentration of GCV. We found significantly increased cytotoxicity in HSVtk/GCV gene therapy after introduction of the HSVtk and Cx37 genes together compared with the cytotoxicity seen after introduction of the HSVtk gene in vitro. Co-expression of the HSVtk and Cx37 genes potentiates HSVtk/GCV gene therapy through the bystander effect. Conclusion : These results indicated that the increase of GJIC using Cx37 have potentiated the bystander effect of HSVtk/GCV therapy, and may be a new approach to improve response in suicidal cancer gene therapy.

Medico-Surgical Cooperative Treatment of Pulmonary Atresia with Intact Ventricular Septum (심실중격 결손이 없는 폐동맥 폐쇄의 내과-외과적 협동치료)

  • Kim, Kyeong Sik;Kweon, Byeong Chul;Lee, Jong Kyun;Choi, Jae Young;Sul, Jun Hee;Lee, Sung Kyu;Park, Young Whan;Cho, Bum Koo
    • Clinical and Experimental Pediatrics
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    • v.46 no.3
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    • pp.250-258
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    • 2003
  • Purpose : The actual clinical examples of co-appliance of catheter intervention with surgical procedures in the treatment of pulmonary atresia with an intact ventricular septum(PA/IVS) which we have experienced in our institution are here shown, and the anatomical and hemodynamical profiles between each method is compared. Methods : Medical records of 33 patients with PA/IVS who underwent various treatment from January, 1995 to December, 2000 were reviewed for a retrograde study. Results : In three out of 10 patients who underwent percutaneous balloon pulmonary valvotomy (PPV), residual pulmonary stenosis were observed in their out patient department(OPD) follow-ups, eventually necessitatig balloon pulmonary valvuloplasty(BPV). One out of three patients exhibited deterioration of tricuspid regurgitation after BPV, requiring surgical tricuspid annuloplasty(TAP). Two out of the seven patients who received primarily surgical right ventricle outlet tract(RVOT) repair without any systemic-pulmonary shunt or intervention needed additional intervention employing cardiac catheterization after operation. Two patients received interventional catheterization before surgical RVOT repair. In five out of 11 cases of Fontan type operation, coil embolization of collateral circulation was done before total cavo-pulmonary connection(TCPC), and in three cases, interventional catheterization was needed after TCPC. Conclusion : Both medical and surgical treatment modalities are widely used in management of PA/IVS patients, and recent results prove that medico-surgical cooperative treatment is essential.

Residual Characteristics and Safety Assessments of Bifenthrin, Carbendazim and Metconazole in Angelica gigas Nakai (당귀 중 bifenthrin, carbendazim, metconazole의 잔류 특성 및 안전성 평가)

  • Jeong, Hye Rim;Noh, Hyun Ho;Lee, Jae Yun;Park, Hyo Kyoung;Jin, Me Jee;Kim, Jin Chan;Hong, Su Myeong;Kyung, Kee Sung
    • The Korean Journal of Pesticide Science
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    • v.21 no.1
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    • pp.97-105
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    • 2017
  • This study was carried out to determine residual characteristics and to evaluate safety of bifenthrin, carbendazim and metconazole in minor crop, Angelica gigas Nakai. The test pesticides were sprayed onto the crop according to the combinations of spray days before harvest and frequency and then sampling was performed at the harvest day. Non-systemic pesticide bifenthrin was not detected in all samples, whereas systemic pesticides, carbendazim and metconazole, were detected from the crop in the range of from 0.14 to 0.49 and from 0.19 to 0.26, respectively. These results indicated that residual characteristics of the test pesticides in Angelica gigas Nakai were affected by their systemic properties. Also, residual concentration of carbendazim and metconazole in the crop was increased as more spraying frequency and spraying more closer to harvest day. And residual concentration of carbendazim in the crop on the last spraying day was 2.1 times higher than that of metconazole because nominal spraying dose of carbendazim was higher than that of metconazole by 1.9 times. The residue levels of the test pesticides in the crop were evaluated to be safe, considering their %ADIs were less than 0.9%.

Analysis of the consumption pattern of delivery food according to food-related lifestyle (식생활라이프스타일에 따른 배달음식의 소비성향 분석)

  • Heo, So-Jeong;Bae, Hyun-Joo
    • Journal of Nutrition and Health
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    • v.53 no.5
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    • pp.547-561
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    • 2020
  • Purpose: This study was conducted to segment the delivery food market and to develop customized products and services. Methods: This study analyzed 636 responses collected from customers who ordered delivery food. Statistical analyses were conducted using the SPSS program (ver. 25.0) for frequency analysis, χ2-test, one-way analysis of variance, factor analysis, and cluster analysis. Results: Four factors were extracted by exploratory factor analysis (safety-orientation, convenience-orientation, taste-orientation, and economy-orientation) to explain the consumers' food-related lifestyles. The results of cluster analysis indicated that the 'low-interest group', 'convenience and economy-oriented group', and 'gourmet and economy-oriented group' should be regarded as the target segments. Characteristic analysis of each cluster showed that lowinterest group had higher rates of married (67.1%) and living with family (85.4%) than other clusters. The convenience and the economy-oriented group had higher rates of living alone (28.9%) than others. The gourmet and the economy-oriented group had a higher percentage of unmarried (62.0%) than the others. In addition, the average age of convenience and economy-oriented group (32.3 years) and gourmet and economy-oriented group (32.5 years) were significantly lower than the safety seeker (40.0 years) (p < 0.001). Difference analysis of the consumption practice according to the cluster, revealed significant differences in the order frequency (p < 0.001), main day to order (p < 0.05), source of information about delivery food (p < 0.001), order method (p < 0.001), and co-consumer (p < 0.01). In addition, the convenience and the economy-oriented group had significantly higher overall satisfaction than the others (p < 0.001). Conclusion: These findings suggest that customer segmentation based on a food-related lifestyle can be used to build a successful marketing strategy. Therefore, restaurant managers and delivery platform operators should consider developing products and services according to the segmentation to maximize customer satisfaction.

An Efficient Estimation of Place Brand Image Power Based on Text Mining Technology (텍스트마이닝 기반의 효율적인 장소 브랜드 이미지 강도 측정 방법)

  • Choi, Sukjae;Jeon, Jongshik;Subrata, Biswas;Kwon, Ohbyung
    • Journal of Intelligence and Information Systems
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    • v.21 no.2
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    • pp.113-129
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    • 2015
  • Location branding is a very important income making activity, by giving special meanings to a specific location while producing identity and communal value which are based around the understanding of a place's location branding concept methodology. Many other areas, such as marketing, architecture, and city construction, exert an influence creating an impressive brand image. A place brand which shows great recognition to both native people of S. Korea and foreigners creates significant economic effects. There has been research on creating a strategically and detailed place brand image, and the representative research has been carried out by Anholt who surveyed two million people from 50 different countries. However, the investigation, including survey research, required a great deal of effort from the workforce and required significant expense. As a result, there is a need to make more affordable, objective and effective research methods. The purpose of this paper is to find a way to measure the intensity of the image of the brand objective and at a low cost through text mining purposes. The proposed method extracts the keyword and the factors constructing the location brand image from the related web documents. In this way, we can measure the brand image intensity of the specific location. The performance of the proposed methodology was verified through comparison with Anholt's 50 city image consistency index ranking around the world. Four methods are applied to the test. First, RNADOM method artificially ranks the cities included in the experiment. HUMAN method firstly makes a questionnaire and selects 9 volunteers who are well acquainted with brand management and at the same time cities to evaluate. Then they are requested to rank the cities and compared with the Anholt's evaluation results. TM method applies the proposed method to evaluate the cities with all evaluation criteria. TM-LEARN, which is the extended method of TM, selects significant evaluation items from the items in every criterion. Then the method evaluates the cities with all selected evaluation criteria. RMSE is used to as a metric to compare the evaluation results. Experimental results suggested by this paper's methodology are as follows: Firstly, compared to the evaluation method that targets ordinary people, this method appeared to be more accurate. Secondly, compared to the traditional survey method, the time and the cost are much less because in this research we used automated means. Thirdly, this proposed methodology is very timely because it can be evaluated from time to time. Fourthly, compared to Anholt's method which evaluated only for an already specified city, this proposed methodology is applicable to any location. Finally, this proposed methodology has a relatively high objectivity because our research was conducted based on open source data. As a result, our city image evaluation text mining approach has found validity in terms of accuracy, cost-effectiveness, timeliness, scalability, and reliability. The proposed method provides managers with clear guidelines regarding brand management in public and private sectors. As public sectors such as local officers, the proposed method could be used to formulate strategies and enhance the image of their places in an efficient manner. Rather than conducting heavy questionnaires, the local officers could monitor the current place image very shortly a priori, than may make decisions to go over the formal place image test only if the evaluation results from the proposed method are not ordinary no matter what the results indicate opportunity or threat to the place. Moreover, with co-using the morphological analysis, extracting meaningful facets of place brand from text, sentiment analysis and more with the proposed method, marketing strategy planners or civil engineering professionals may obtain deeper and more abundant insights for better place rand images. In the future, a prototype system will be implemented to show the feasibility of the idea proposed in this paper.

Carbon Storage and Uptake by Deciduous Tree Species for Urban Landscape (도시 낙엽성 조경수종의 탄소저장 및 흡수)

  • Jo, Hyun-Kil;Ahn, Tae-Won
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.5
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    • pp.160-168
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    • 2012
  • This study generated regression models to estimate the carbon storage and uptake from the urban deciduous landscape trees through a direct harvesting method, and established essential information to quantify carbon reduction from urban greenspace. Tree species for the study included Acer palmatum, Zelkova serrata, Prunus yedoensis, and Ginkgo biloba, which are usually planted as urban landscape trees. Tree individuals for each species were sampled reflecting various diameter sizes at a given interval. The study measured biomass for each part including the roots of sample trees to compute the total carbon storage per tree. Annual carbon uptake per tree was quantified by analyzing radial growth rates of stem samples at breast height. The study then derived a regression model easily applicable in estimating carbon storage and uptake per tree for the 4 species by using diameter at breast height(dbh) as an independent variable. All the regression models showed high fitness with $r^2$ values of 0.94~0.99. Carbon storage and uptake per tree and their differences between diameter classes increased as the diameter sizes got larger. The carbon storage and uptake tended to be greatest with Zelkova serrata in the same diameter sizes, followed by Prunus yedoensis and Ginkgo biloba in order. A Zelkova serrata tree with 15cm in dbh stored about 54kg of carbon and annually sequestered 7 kg, based on a regression model for the species. The study has broken new grounds to overcome limitations of the past studies which substituted, due to a difficulty in direct cutting and root digging of urban landscape trees, coefficients from the forest trees such as biomass expansion factors, ratios of below ground/above ground biomass, and diameter growth rates. Study results can be useful as a tool or skill to evaluate carbon reduction by landscape trees in urban greenspace projects of the government.

A Study on the Stability Test for the Cream Containing Suaeda Asparagoides Extract (나문재 추출물 함유 크림의 안정성 평가에 관한 연구)

  • Park, Soo-Nam;Jeon, So-Mi;Ahn, Jeung-Youb
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.33 no.4
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    • pp.231-238
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    • 2007
  • In the previous study, the anti-oxidant activity of extract/fraction of Sueada asparagoides (SA) was investigated and the results showed that the ethylacetate (EtOAc) fraction and its aglycone fraction had the best performance on the free radical scavenging activity, reactive oxygen species scavenging (ROS) activity and cell protective activity (J. Soc. Cosme. Scientists Korea, 33(3), 145 (2007)). In this study, the stability of cream containing 0.3% SA EtOAc extract (called extract below) was evaluated. pH, viscosity and absorbance (363 nm) were measured under the 4 different temperatures ($0^{\circ}C,\;25{\circ}C,\;37{\circ}C\;and\;45{\circ}C$) and under the sun light at the 4 week intervals during the 12 weeks in total. The control cream without containing the extract did not show pH change under the different temperatures mentioned above. However, the pH of the cream the extract was decreased 0.08 at the temperature ranges of $0^{\circ}C\;to\;37^{\circ}C$. Under the $45^{\circ}C$ and sun light condition, the pH was decreased 0.51 and 0.66, respectively. The cream containing the extract did not show absorbance change at the temperature ranges of 0 to $37^{\circ}C$ for 12 weeks. Instead, the absorbance of the cream treated under $45^{\circ}C$ and sun light condition was decreased 7.6 % and 7.4 %, respectively. This decrease in absorbance is relatively small compared to the 48.3 % decrease of the extract sampled from the cream using ethanol solution. This indicates that the extract is stabilized in the cream. After treating the cream for 12 weeks under the different temperatures, the viscosity was measured for the cream containing the extract and control cream. The values were increased by 1,748 cPs in average compared to the initial value for the former and by 951 cPs in average for the latter. On the other hand, the viscosity of control cream treated under the sun light for 12 weeks was significantly decreased (4,022 cPs) relative to the cream containing the extract, which showed 2,484 cPs increase in viscosity. This indicates that the SA extract contributes to the stability of the emulsion product by protective effect to maintain the viscosity of the cream against sun light. In addition, any change in color or smell was not observed through 12 weeks of the experimental time period. Thus, it is concluded that it is still not clear in the stability of the cream containing the extract when it is stored for the long time. Accordingly, it is suggested that further study is needed to provide more information to the manufactures, who are seeking for the application of the extract to improve the anti-oxidant activity and stability of cosmetic products.