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Effect of Nitrogen Impurity on Process Design of $CO_2$ Marine Geological Storage: Evaluation of Equation of State and Optimization of Binary Parameter (질소 불순물이 이산화탄소 해양 지중저장 공정설계에 미치는 영향 평가: 상태방정식의 비교 분석 및 이성분 매개변수 최적화)

  • Huh, Cheol;Kang, Seong-Gil
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.3
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    • pp.217-226
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    • 2009
  • Marine geological storage of $CO_2$ is regarded as one of the most promising options to response climate change. Marine geological storage of $CO_2$ is to capture $CO_2$ from major point sources, to transport to the storage sites and to store $CO_2$ into the marine geological structure such as deep sea saline aquifer. Up to now, process design for this $CO_2$ marine geological storage has been carried out mainly on pure $CO_2$. Unfortunately the captured $CO_2$ mixture contains many impurities such as $N_2$, $O_2$, Ar, $H_2O$, $SO_x$, $H_2S$. A small amount of impurities can change the thermodynamic properties and then significantly affect the compression, purification and transport processes. In order to design a reliable $CO_2$ marine geological storage system, it is necessary to perform numerical process simulation using thermodynamic equation of state. The purpose of the present paper is to compare and analyse the relevant equations of state including PR, PRBM, RKS and SRK equation of state for $CO_2-N_2$ mixture. To evaluate the predictive accuracy of the equation of the state, we compared numerical calculation results with reference experimental data. In addition, optimum binary parameter to consider the interaction of $CO_2$ and $N_2$ molecules was suggested based on the mean absolute percent error. In conclusion, we suggest the most reliable equation of state and relevant binary parameter in designing the $CO_2-N_2$ mixture marine geological storage process.

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A Study on the Factors Causing Analytical Errors through the Estimation of Uncertainty for Cadmium and Lead Analysis in Tomato Paste (불확도 추정을 통한 토마토 페이스트에서 카드뮴 및 납 분석의 오차 발생 요인 규명)

  • Kim, Ji-Young;Kim, Young-Jun;Yoo, Ji-Hyock;Lee, Ji-Ho;Kim, Min-Ji;Kang, Dae-Won;Im, Geon-Jae;Hong, Moo-Ki;Shin, Young-Jae;Kim, Won-Il
    • Korean Journal of Environmental Agriculture
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    • v.30 no.2
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    • pp.169-178
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    • 2011
  • BACKGROUND: This study aimed to estimate the measurement uncertainty associated with determination of cadmium and lead from tomato paste by ICP/MS. The sources of measurement uncertainty (i.e. sample weight, final volume, standard weight, purity, molecular weight, working standard solution, calibration curve, recovery and repeatability) in associated with the analysis of cadmium and lead were evaluated. METHODS AND RESULTS: The guide to the expression of uncertainty was used for the GUM (Guide to the expression of Uncertainty in Measurement) and Draft EURACHEM/CITAC (EURACHEM: A network of organization for analytical chemistry in Europe/Co-Operation on International Traceability in Analytical Chemistry) Guide with mathematical calculation and statistical analysis. The uncertainty components were evaluated by either Type A or Type B methods and the combined standard uncertainty were calculated by statistical analysis using several factors. Expected uncertainty of cadmium and lead was $0.106{\pm}0.015$ mg/kg (k=2.09) and $0.302{\pm}0.029$ mg/kg (k=2.16), on basis of 95% confidence of Certified Reference Material (CRM) which was within certification range of $0.112{\pm}0.007$ mg/kg for cadmium (k=2.03) and $0.316{\pm}0.021$ mg/kg for lead (k=2.01), respectively. CONCLUSION(s): The most influential components in the uncertainty of heavy metals analysis were confirmed as recovery, standard calibration curve and standard solution were identified as the most influential components causing uncertainty of heavy metal analysis. Therefore, more careful consideration is required in these steps to reduce uncertainty of heavy metals analysis in tomato paste.

Genetic Analysis of Natural Microflora in the Stored Joraengyi Rice Cake and Their Capability of Propionic Acid Production (조랭이 떡에 존재하는 자연균총 유전자 군집분석 및 천연유래 프로피온산 생성능 분석)

  • Park, Hee-Dae;Chae, Jung-Kyu;Ha, Sang-Do
    • Journal of Food Hygiene and Safety
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    • v.33 no.5
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    • pp.375-382
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    • 2018
  • This study was conducted to analyze the microbial community and propionic acid production ability of natural microflora in the rice cakes. Genetic analysis of natural microflora in Jorangyi rice cake was performed to select propionic acid - producing bacteria. Selected propionic acid-producing bacteria were cultivated in TSB (tryptic soy broth) supplemented with glucose, and growth characteristics were analyzed by temperature and production of propionic acid was analyzed by gas chromatography (GC-FID). Linearity, detection limit, quantitative limit, and recovery rate were measured to verify propionic acid assay. A total of 98 microbial strains were detected from microflora of Joraengyi rice cake that grew after expiration of shelf life. Lactobacillus casei group accounted for 50.48% and Lactobacillus buchneri was 29.60%. Propionic acid - producing bacteria were Propionibacterium thoenii, P. cyclohexanicum, Propionibacterium_uc, P. jensenii, and P. freudenreichii. Natural bacteria and Lactobacillus spp. did not produce propionic acid during 14 days but P. cyclohexanicum, P. freudenreichii subsp. Shermanii, P. thoenii and P. jesenii produced $263.47{\mu}g/mL$, $338.90{\mu}g/mL$, $325.43{\mu}g/mL$ and $222.17{\mu}g/mL$ during 4 days and 2,462.02 and 2,904.78, 2,220.64, $3,519.17{\mu}g/mL$ during 14 days. As a result of this study, it was affirmed that the natural microflora of Joraengyi rice cake during storage can produce propionic acid from natural sources even if a high concentration of propionic acid is not intentionally added. Because of characteristics of rice cake composed of starch and glucose. This study will be used as a recognition criterion to detect natural preservatives such as propionic acid in starchy foods such as rice cakes and as reference standard safety management data.

Packing effects on the intracavitary radiation therapy of the utaine lervix cancer ($^{192}Ir$source를 이용할 자궁경부암 강내치료시 사용하는 packing의 효과에 대한 고찰)

  • Cho, Jung-Kun;Lee, Du-Hyun;Si, Chang-Kun;Choi, Yoon-Kyung;Kim, Tae-Yoon
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.1
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    • pp.73-77
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    • 2004
  • Purpose of the radio-therapy is maximize the radiation dose to the tumor while minimizing the dose to the critical organ. Carcinoma of the uterine cervix treatment are external irradiation or an interstitial brachtheraphy make use of isotope. Brachytherapy is a method of radiotherapy in advantage to achieve better local control with minimum radiation toxicity in comparison with external irradiation because radiation dose is distributed according to the inverse square low of gamma-ray emitted from the implanted sources. Authors make use of the patients data which 192Ir gives medical treatment intrcavity. Intracavitary radiation of the uterine cervix cancer, critical organ take $20\%$ below than exposure dose of A point in the ICRU report. None the less of the advice, Radiation proctitis and radiation cystitis are frequent and problematic early complications in patients treated with radiation for the uterine cervix cancer. In brachytherapy of uterine cervical cancer using a high dose rate remote afterloading system, it is of prime importance to deliver a accurate dose in each fractionated treatment by minimizing the difference between the pre-treatment planned and post-treatment calculated doses. Use of packing to reduce late complications intracavitary radiation of the uterine cervix cancer. Bladder and rectum changes exposure dose rate by radiotherphy make use of packing.

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$CO_2$ Transport for CCS Application in Republic of Korea (이산화탄소 포집 및 저장 실용화를 위한 대한민국에서의 이산화탄소 수송)

  • Huh, Cheol;Kang, Seong-Gil;Cho, Mang-Ik
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.13 no.1
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    • pp.18-29
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    • 2010
  • Offshore subsurface storage of $CO_2$ is regarded as one of the most promising options to response severe climate change. Marine geological storage of $CO_2$ is to capture $CO_2$ from major point sources, to transport to the storage sites and to store $CO_2$ into the offshore subsurface geological structure such as the depleted gas reservoir and deep sea saline aquifer. Since 2005, we have developed relevant technologies for marine geological storage of $CO_2$. Those technologies include possible storage site surveys and basic designs for $CO_2$ transport and storage processes. To design a reliable $CO_2$ marine geological storage system, we devised a hypothetical scenario and used a numerical simulation tool to study its detailed processes. The process of transport $CO_2$ from the onshore capture sites to the offshore storage sites can be simulated with a thermodynamic equation of state. Before going to main calculation of process design, we compared and analyzed the relevant equation of states. To evaluate the predictive accuracies of the examined equation of states, we compare the results of numerical calculations with experimental reference data. Up to now, process design for this $CO_2$ marine geological storage has been carried out mainly on pure $CO_2$. Unfortunately the captured $CO_2$ mixture contains many impurities such as $N_2$, $O_2$, Ar, $H_{2}O$, $SO_{\chi}$, $H_{2}S$. A small amount of impurities can change the thermodynamic properties and then significantly affect the compression, purification and transport processes. This paper analyzes the major design parameters that are useful for constructing onshore and offshore $CO_2$ transport systems. On the basis of a parametric study of the hypothetical scenario, we suggest relevant variation ranges for the design parameters, particularly the flow rate, diameter, temperature, and pressure.

Estimation of Biomass Resource Conversion Factor and Potential Production in Agricultural Sector (농업부문 바이오매스 자원 환산계수 및 잠재발생량 산정)

  • Park, Woo-Kyun;Park, Noh-Back;Shin, Joung-Du;Hong, Seung-Gil;Kwon, Soon-Ik
    • Korean Journal of Environmental Agriculture
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    • v.30 no.3
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    • pp.252-260
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    • 2011
  • BACKGROUND: Currently, national biomass inventory are being established for efficient management of the potential energy sources. Among the various types of biomass, agricultural wastes are considered to take the biggest portion of the total annual biomass generated in Korea, implying its importance. However, the currently estimated amount is not reliable because the old reference data are still used to estimate total annual amount of agricultural wastes. METHODS AND RESULTS: Therefore, to provide reliable estimation data, a correct conversion factor obtained by taking into account the current situation is required. For this, the current study was conducted to provide the conversion factors for each representative 8 crop through a field cultivation study. Also conversion factors for 18 crops were calculated using the average amount of each crop produced during 2004 and 2008, subsequently; total amount of agricultural wastes generated in 2009 was estimated using these conversion factors. The total biomass of rice straw and rice husk generated in 2009 were 6.5 and 1.1 million tons, respectively, which consist 75% of the total agricultural based wastes, while the total biomass of pepper shoots and apple pruning twigs were 1.0 and 0.6 million tons, respectively. Despite the high amount of rice-based biomass, their applicability for bio-energy production is low due to conventional utilization of these materials for animal feeds and beds for animal husbandry. In addition to exact estimation of the total biomass, temporal variations in both generated amount and the type of agricultural biomass materials are also important for efficient utilization; fruit pruning twigs (January to March); barley-, been-, and mustard-related waste materials (April to June); rice-related waste (September to October). CONCLUSION(s): Such information provided in this study can be used to establish a master plan for efficient utilization of the agricultural wastes on purpose of bio-energy production.

Influence of lime and phosphorus application on nutrient uptake by corn in newly reclaimed acidic soils -I. With special reference to P sources and distribution of Zn among leaves (산성신개간토양(酸性新開墾土壤)에서 석회(石灰) 및 인산(燐酸)이 옥수수의 양분(養分) 흡수(吸收)에 미치는 영향(影響) -I. 인산비종(燐酸肥種)과 아연(亞鉛)의 흡수(吸收) 및 엽위별분포(葉位別分布))

  • Kim, Young Koo;Hong, Chong Woon;Oh, Yong Taeg
    • Korean Journal of Soil Science and Fertilizer
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    • v.8 no.4
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    • pp.189-194
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    • 1975
  • On a newly reclaimed acidic soil, investigation was made to find out the influence of lime and P application at a largeg uantity on the uptake of Zn by corn and its distribution among the leaves, under afactorial combination with two levels of Zn, lime, and P. The results are summarized as following. 1. The application of lime for neutralization of soil significantly reduced the uptake of Zn by corn. 2. Liberal doses of P (5% of P absorption coefficient of soil; 500ppm) applied before sowing did not influence the uptake of Zn. 3. The concentration of Zn in bottom leaves better reflected the Zn uptake status of corn than the upper leaves. The concentration of Zn in bottom leaves responded clearly to the treatments of lime and Zn, while those of upper leaves tended to be constant unresponding to application of lime and Zn. 4. On the present experimental condition, the yield of corn was increased with the increase of P application. But the concentration of P in plant tissue remained constant under different P levels. 5. Application of lime (calcium hydroxide) on low P plots, depressed the yield of corn significantly. It was speculated that the lime applied at large dose made the applied P less available to corn.

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A Study on the Costumes of the Characters of Higyongru Banghwoedo (<희경루방회도(喜慶樓榜會圖)> 속 인물들의 복식 고찰)

  • Bae, Jin-Hee;Lee, Eun-Joo
    • Korean Journal of Heritage: History & Science
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    • v.51 no.4
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    • pp.44-65
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    • 2018
  • This study examined the costumes of the characters in the painting titled Hig yongru Banghwoedo, which was designated as National Treasure No. 1879 in September 2015, and is currently kept in the Dongguk University Museum. The painting depicts a social gathering of Joseon aristocrats held at the higyongru, or watch tower, of the Gwangjumok, a government office, in 1567. It is characterized by the delicate illustration of the government officials, the main characters of the gathering, and the hyangri, ajeon, najang, chorye, akgong, and yeogi, the lower-class employees of the office. In order to investigate the costumes they wore, diverse materials including literature, costume artifacts, and paintings were used as reference sources. The scope of the study was limited to the characters' headdress and gown, and the accessories attached to the former. The study of men's clothing revealed that officials wore a samo and a red dalryeong as basic attire. In addition, it is presumed that they wore a belt indicating their official rank in the hierarchy, and a pair of black shoes. Retired officials wore a heuklip wrapped in horsehair or silk fabric with a red jing-nyeong and a doah. The hyangri wore a heukjukbanglip on their head, as well as a white jing-nyeong and a belted doah. In the Goryeo period, the banglip was a type of official headdress worn by members of the aristocratic elite ranked immediately below the king, but in Joseon it was demoted as the official headgear of the hyangri class, which was confirmed through Higyongru Banghwoedo. The ajeon wore a heuklip on their head, and a white jing-nyeong and a doah at the waist. As a rule, the najang wore a chogun on the head, and a banbieui on cheolrik and chungmokdai, but the najang in Higyongru Banghwoedo are depicted wearing a chogun and a cheolrik without a banbieui. Also, the chorye wore a heuklip wrapped in hemp cloth with a red cheolrik, whereas the akgong wore a somoja and a red cheolrik. Female entertainers, both adults and children, are depicted in the painting as either serving the aristocrats, dancing, or playing a musical instrument, wearing their hair in a voluminous, round, high bun, and dressed in a red daiyo, a hwangjangsam with a straight or reclined collar, and a belt. Notably, the donggi, i.e. young gisaeng, are shown wearing their hair in two short braids, and ddressed in a red gown with a y-shaped collar, or po.

The food and nutrient intakes from daily processed food in Korean adults: based on the 6th Korea National Health and Nutrition Examination Survey data (2013~2015) (한국 성인의 가공식품으로부터의 식품 및 영양소 섭취량 평가 : 제 6기 (2013~2015) 국민건강영양조사를 바탕으로)

  • Ha, Ae Wha;Kim, Woo Kyoung
    • Journal of Nutrition and Health
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    • v.52 no.5
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    • pp.422-434
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    • 2019
  • Purpose: The consumption of processed foods has recently been increasing due to changes in the living environment. The purpose of this study was to identify the contribution of processed food to the nutrient intake of adult Koreans. Methods: A total of 15,760 adult people in the $6^{th}$ National Health and Nutrition Examination Survey (2013 ~ 2015) were included in this study. According to the Korea Food and Drug Administration's classification criteria for processed foods, the 24 hour dietary recall data of the subjects were classified as processed food or natural food. The processed food intake, nutrient intake and major processed food sources by food groups were analyzed. Results: Men consumed more processed foods than did the women. Consumption of processed foods decreased with age, but it increased with the education level and the income level. The total daily processed food intake accounted for 68.1% of the total food intake. The food groups with high processed food intake were beverage, vegetables, cereals and grain products, fruits, and milk and dairy products in this order. The top food source of each food groups were beer, kimchi, bread, processed apple products, and milk. After adjusting for age, gender, and energy intake, all the nutrient intakes and percentage of dietary reference intakes for Koreans, except carbohydrates, were significantly higher in processed foods than in natural foods. The sodium intake from the processed food was 96.3% of total daily sodium intake. The intakes of nutrients from processed foods, excluding vitamins C, dietary fiber, iron, and vitamin A, were higher in men than in women. The intake of sodium from processed foods was highest for people of 30 ~ 49 years of age, and the intake of sodium from processed foods decreased for people over 50. Conclusion: Korean adults consumed more processed food than the natural food, consuming more calories and most of the nutrients from the processed food overall total daily intakes. The intake of processed foods is expected to further increase in the future, and nutritional education and research on the ingestion and selection of healthy processed foods are necessary.

The Effect of Consumers' Value Motives on the Perception of Blog Reviews Credibility: the Moderation Effect of Tie Strength (소비자의 가치 추구 동인이 블로그 리뷰의 신뢰성 지각에 미치는 영향: 유대강도에 따른 조절효과를 중심으로)

  • Chu, Wujin;Roh, Min Jung
    • Asia Marketing Journal
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    • v.13 no.4
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    • pp.159-189
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    • 2012
  • What attracts consumers to bloggers' reviews? Consumers would be attracted both by the Bloggers' expertise (i.e., knowledge and experience) and by his/her unbiased manner of delivering information. Expertise and trustworthiness are both virtues of information sources, particularly when there is uncertainty in decision-making. Noting this point, we postulate that consumers' motives determine the relative weights they place on expertise and trustworthiness. In addition, our hypotheses assume that tie strength moderates consumers' expectation on bloggers' expertise and trustworthiness: with expectation on expertise enhanced for power-blog user-group (weak-ties), and an expectation on trustworthiness elevated for personal-blog user-group (strong-ties). Finally, we theorize that the effect of credibility on willingness to accept a review is moderated by tie strength; the predictive power of credibility is more prominent for the personal-blog user-groups than for the power-blog user groups. To support these assumptions, we conducted a field survey with blog users, collecting retrospective self-report data. The "gourmet shop" was chosen as a target product category, and obtained data analyzed by structural equations modeling. Findings from these data provide empirical support for our theoretical predictions. First, we found that the purposive motive aimed at satisfying instrumental information needs increases reliance on bloggers' expertise, but interpersonal connectivity value for alleviating loneliness elevates reliance on bloggers' trustworthiness. Second, expertise-based credibility is more prominent for power-blog user-groups than for personal-blog user-groups. While strong ties attract consumers with trustworthiness based on close emotional bonds, weak ties gain consumers' attention with new, non-redundant information (Levin & Cross, 2004). Thus, when the existing knowledge system, used in strong ties, does not work as smoothly for addressing an impending problem, the weak-tie source can be utilized as a handy reference. Thus, we can anticipate that power bloggers secure credibility by virtue of their expertise while personal bloggers trade off on their trustworthiness. Our analysis demonstrates that power bloggers appeal more strongly to consumers than do personal bloggers in the area of expertise-based credibility. Finally, the effect of review credibility on willingness to accept a review is higher for the personal-blog user-group than for the power-blog user-group. Actually, the inference that review credibility is a potent predictor of assessing willingness to accept a review is grounded on the analogy that attitude is an effective indicator of purchase intention. However, if memory about established attitudes is blocked, the predictive power of attitude on purchase intention is considerably diminished. Likewise, the effect of credibility on willingness to accept a review can be affected by certain moderators. Inspired by this analogy, we introduced tie strength as a possible moderator and demonstrated that tie strength moderated the effect of credibility on willingness to accept a review. Previously, Levin and Cross (2004) showed that credibility mediates strong-ties through receipt of knowledge, but this credibility mediation is not observed for weak-ties, where a direct path to it is activated. Thus, the predictive power of credibility on behavioral intention - that is, willingness to accept a review - is expected to be higher for strong-ties.

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