• Title/Summary/Keyword: packing factor

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An Experimental Study on the Thermal Characteristics of Ice Storage Tank - Focusing on the Adiabatic Effects of Ice Storage Tank - (직접접촉식 빙축열조의 전열특성에 관한 연구 - 빙축열조의 단열영향을 중심으로 -)

  • Lee, Chae-Moon;Park, Jung-Won;Cho, Nam-Chul;Park, Sang-Rok;Kim, Il-Gyoum;Kim, Dong-Chun;Kim, Young-Ki;Yim, Chang-Soon
    • Solar Energy
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    • v.17 no.2
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    • pp.75-89
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    • 1997
  • In this paper, the operating thermal characterictics of liquid-ice was expeimentally investigated in an adiabatic and a non-adiabatic direct contact liquid-ice heat exchanger. Experiments were carried out varing inlet temperature, Ice Packing Factor, and the flow rate of heat transfer fluid. The higher inlet temperature and the more much inlet flow rate, thermal stratification in liquid-ice heat exchanger was established faster. In the case of adiabatic ice storage tank, temperature distribution was a little higher at all conditions than that of non-adiabatic one. The ratio of latent energy to total discharge energy($E_{\lambda}/E_[tot}$) was about 80%, and the discharge of latent heat energy was appeared rapidly as inlet temperature and flow rate were higher.

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Studies on the Problems about Preparation and Packagin of Granular Enzymic Digestives (과립소화효소제(顆粒消化酵素劑)의 제조(製造) 및 포장(包裝)에 따른 문제점(問題點) 검토(檢討))

  • Lee, Seung-Koo;Yi, Pyung-Kuk;Kim, Cheong-Soo;Bae, Young-Hwan
    • Journal of Pharmaceutical Investigation
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    • v.1 no.1
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    • pp.90-100
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    • 1971
  • It is well known that the commonly used granular enzymic digestives are easy to diminish it's potency through preparation and custody. We made an experinent to know the proper way of manufacturing and keeping the granules without a loss of potency by $L_8$ orthogonal Tables. The factors, we considered, decomposition of enzyme activity through manufacturing are (1) sufficiency of granules drying (2) with or without sodium bicarbonate $(NaHCO_3)$ in gramules (3) separate wet granulation of enzyme and the rest of the component or mix together (4) kind of packing materials (Polycello or quartet silner paper) Besides we counted (5) humidity (6) temperature as block factors. Then we tested the potency of each sample by intervals of. a week, 2 weeks and we foretelled the potency of after one year by the life test. From the experimental results, main factor of activity loss is preserving humidity. Therefor the sufficiency of packing is became a main problem and the granules have to be made by separate wet granulation to inhibit it's decomposition. Temperature is the factor that accelerates loss of activity by humidity but does not so much by itself mixing enzyme toge therwith $NaHCO_3$ is not became a matter so far as it is dried.

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Importance of Green Density of Nanoparticle Precursor Film in Microstructural Development and Photovoltaic Properties of CuInSe2 Thin Films

  • Hwang, Yoonjung;Lim, Ye Seul;Lee, Byung-Seok;Park, Young-Il;Lee, Doh-Kwon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.471.2-471.2
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    • 2014
  • We demonstrate here that an improvement in precursor film density (green density) leads to a great enhancement in the photovoltaic performance of CuInSe2 (CISe) thin film solar cells fabricated with Cu-In nanoparticle precursor films via chemical solution deposition. A cold-isostatic pressing (CIP) technique was applied to uniformly compress the precursor film over the entire surface (measuring 3~4 cm2) and was found to increase its relative density (particle packing density) by ca. 20%, which resulted in an appreciable improvement in the microstructural features of the sintered CISe film in terms of lower porosity, reduced grain boundaries, and a more uniform surface morphology. The low-bandgap (Eg=1.0 eV) CISe PV devices with the CIP-treated film exhibited greatly enhanced open-circuit voltage (VOC, from 0.265 V to 0.413 V) and fill factor (FF, from 0.34 to 0.55), as compared to the control devices. As a consequence, an almost 3-fold increase in the average power conversion efficiency, 3.0 to 8.2% (with the highest value of 9.02%), was realized without an anti-reflection coating. A diode analysis revealed that the enhanced VOC and FF were essentially attributed to the reduced reverse saturation current density (j0) and diode ideality factor (n). This is associated with the suppressed recombination, likely due to the reduction in recombination sites such as grain/air surfaces (pores), inter-granular interfaces, and defective CISe/CdS junctions in the CIP-treated device. From the temperature dependences of VOC, it was confirmed that the CIP-treated devices suffer less from interface recombination.

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Study of The Combined High Flowing Self-Compacting Concrete's Cast in Place (병용계 고유동 자기충전 라이닝콘크리트의 현장 타설에 관한 연구)

  • Choi, Wook;Park, Hyun-Myo;Choi, Yun-Wang;Lee, Kwang-Myong;Kim, Gi-Beom;Yoon, Tae-Jung
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.977-980
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    • 2008
  • Recently, the study on the application of SCC(Self-Compacting Concrete) is actively underway, in order to solve the lack of flowability and the poor compacting which is one of the chronic problems of tunnel lining concrete. The aim of this study is that to verify the validity of the application of SCLC(Self-Compacting Lining Concrete) for tunnel lining concrete and to examine the characteristic of flowing and mechanics of SCLC in term of comparing before and after casting SCLC was developed by Packing Factor mix method and casted in field mix-design according to the condition of site and the characteristic of aggregate. Before casting, the tests of the capability of flowability and durability was performed by slump flow, air void and so on. Additionally, the slump flow loss is measured to evaluated the possibility of cast-in-place. Furthermore, considering on the first time SCLC casting applied to the tunnel lining in Korea, it is provided that the careful items and the correct way for construction when applied the SCLC on site.

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Study on the Modeling Technique for Prediction about Pressure Drop of an Intravenous Lung Assist Device (혈관 내 폐 보조장치의 압력손실 예측을 위한 모델링기법에 관한 연구)

  • 김기범;권대규;정경락
    • Journal of Biomedical Engineering Research
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    • v.24 no.4
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    • pp.293-299
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    • 2003
  • In this paper, the correlation of Pressure drop about the Newtonian and non-Newtonian fluid was investigated experimentally for vibrating intravascular lung assist device (VIVLAD) and we determined correlation equation to make a prediction about Pressure drop for designing VIVLAD. Design conditions to predict the pressure drop of the modules were studied through an experimental modeling before inserting the artificial lung assist device into as venous. Experiments were performed by distilled water, glycerol/water mixed solution(40% glycerol) of Newtonian fluids. and the bovine blood of non-Newtonian fluids. These fluids were flowed outside and parallel of hollow fiber membranes. Also we measured pressure drop according to the number of the fiber membranes which ware inserted into the inside diameter of shell of 3 cm, and developed the prediction equations by curve fitting method based on correlation between the experimental pressure drop and the frontal area or the packing density of device. The result showed that the Pressure drop and the friction factor of the water/glycerol mixed solution were similar to that of bovine blood. It was showed that the water/glycerol mixed solution (40% glycerol) could be used for measuring the pressure drop and the friction factor instead of the bovine blood. Also, we could estimate the prediction equation of pressure drop and friction factor as the function of Packing density at the number of hollow fibers. We obtained the reliance of the prediction equations because the pressure drop and the friction factor measured from the experiments were similar to that from the prediction equation. These results may be used to further usefulness for the design of VIVLAD.

Effects of Logistics organization practices and Resources Circulation factor on Firm Performance (물류분야에서의 자원순환형시스템 구축 활동요인과 물류조직특성이 물류성과에 미치는 효과)

  • Lim, Jae-Hwa;Park, Seog-Ha
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.30 no.1
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    • pp.48-58
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    • 2007
  • For a sustainable development, the resources circulation system should be established and required alternative logistics area of enterprises. In this paper, we are to suggest a direction through analysis effects, and reduce, recycle, reuse factor of transportation, material handling, packing, information, management in logistics function, and effects of logistics organization on Firm Performance. We found significant correlations between the constructs extracted above, and between the constructs and firm's performance. This study was conducted with the subjects of manufacturing enterprises with concurrent reviews of literature and statistical analysis, and the meaning of this study would be the analysis of the influencers of the resources circulation system.

Treatment of non-resonant spatial self-shielding effect of double heterogeneous region

  • Tae Young Han;Hyun Chul Lee
    • Nuclear Engineering and Technology
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    • v.55 no.2
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    • pp.749-755
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    • 2023
  • A new approximation method was proposed for treating the non-resonant spatial self-shielding effects of double heterogeneous region such as the double heterogeneous effect of VHTR fuel compact in the thermal energy range and that of BP compact with BISO. The method was developed based on the effective homogenization method and a spherical unit cell model with explicit coated layers and a matrix layer. The self-shielding factor was derived from the relation between the collision probabilities for a double heterogeneous compact and the effective cross section for the homogenized compact. First, the collision probabilities and transmission probabilities for all layers of the spherical model were calculated using conventional collision probability solver. Then, the effective cross section for the homogenized sphere cell representing the homogenized compact was obtained from the transmission probability calculated using the probability density function of a chord length. The verification calculations revealed that the proposed method can predict the self-shielding factor with a maximum error of 2.3% and the double heterogeneous effect with a maximum error of 200 pcm in the typical VHTR problems with various packing fractions and BP compact sizes.

Carpal Tunnel Syndrome among Packing Workers in A Rayon Manufacturing Factory (모 사업장 포장부서 근로자들에서 발생한 수근터널증후군에 대한 조사연구)

  • Lee, Won-Jin;Lee, Eun-Il;Cha, Chul-Whan
    • Journal of Preventive Medicine and Public Health
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    • v.25 no.1 s.37
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    • pp.26-33
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    • 1992
  • The carpal tunnel syndrome is one of the most common peripheral nerve entrapment syndromes. The typical symptoms are pain, numbness and paresthesia in the median nerve territory of the hand. Recently, it is widely recognized that occupational factor is regarded as the important cause of the carpal tunnel syndrome. Clinical study is performed in the 42 female workers who is repetitively working at packing department in a rayon manufacturing factory from November 1991 till March 1992. The study included a questionnaire, physical examinations, and the neurophysiological test. The summary of the results obtained was as follows : 1. Among 42 packing workers, 9 workers(21.4%) were diagnosed as carpal tunnel syndrome by electromyography. The affected side was bilateral in 4 workers(9.5%), right in 4 workers(9.5%), and left in one worker(2.4%). 2. Among 42 subjects, 28 workers(66.7%) complained the clinical symptoms related to carpal tunnel syndrome, 11 workers(26.2%) showed positive Phalen sign, and 7 workers(16.7%) showed positive Tinel sign. 3. Researchers regard electromyographic finding as the gold standard for diagnosis of carpal tunnel syndrome. The sensitivity and specificity of the clinical symptoms to diagnose the carpal tunnel syndrome were 0.89, 0.39 respectively. If the carpal tunnel syndrome is diagnosed by the combination of the positive findings of the symptoms and the physical examinations, either Tinel or Phalen sign, the sensitivity and specificity were 0.67 and 0.76 respectively. Considering above results, though this small number of workers is not adequate for epidemiologic conclusions, carpal tunnel syndrome seems to be an important occupational disorder among packing workers in a rayon manufacturing factory.

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Integrity Evaluation for 3D Cracked Structures(I) (3차원 균열을 갖는 구조물에 대한 건전성 평가(I))

  • Lee, Joon-Seong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.8
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    • pp.3295-3300
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    • 2012
  • Three Dimensional finite element method (FEM) was used to obtain the stress intensity factor for subsurface cracks and surface cracks existing in inhomogeneous materials. A geometry model, i.e. a solid containing one or several 3D cracks is defined. Several distributions of local node density are chosen, and then automatically superposed on one another over the geometry model. Nodes are generated by the bubble packing, and ten-noded quadratic tetrahedral solid elements are generated by the Delaunay triangulation techniques. To examine accuracy and efficiency of the present system, the stress intensity factor for a semi-elliptical surface crack in a plate subjected to uniform tension is calculated, and compared with Raju-Newman's solutions. Then the system is applied to analyze interaction effects of two dissimilar semi-elliptical cracks in a plate subjected to uniform tension.

Microbiological Hazard Analysis for HACCP System Application to Vinegared Pickle Radishes (식초절임 무의 HACCP 시스템 적용을 위한 미생물학적 위해 분석)

  • Kwon, Sang-Chul
    • Journal of Food Hygiene and Safety
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    • v.28 no.1
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    • pp.69-74
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    • 2013
  • This study has been performed for 150 days from February 1 - June 31, 2012 aiming at analyzing biologically hazardous factors in order to develop HACCP system for the vinegared pickle radishes. A process chart was prepared as shown on Fig. 1 by referring to manufacturing process of manufacturer of general vinegared pickle radishes regarding process of raw agricultural products of vinegared pickle radishes, used water, warehousing of additives and packing material, storage, careful selection, washing, peeling off, cutting, sorting out, stuffing (filling), internal packing, metal detection, external packing, storage and consignment (delivery). As a result of measuring Coliform group, Staphylococcus aureus, Salmonella spp., Bacillus cereus, Listeria Monocytogenes, E. coli O157:H7, Clostridium perfringens, Yeast and Mold before and after washing raw radishes, Bacillus cereus was $5.00{\times}10$ CFU/g before washing but it was not detected after washing and Yeast and Mold was $3.80{\times}10^2$ CFU/g before washing but it was reduced to 10 CFU/g after washing and other pathogenic bacteria was not detected. As a result of testing microorganism variation depending on pH (2-5) of seasoning fluid (condiment), pH 3-4 was determined as pH of seasoning fluid as all the bacteria was not detected in pH3-4. As a result of testing air-borne bacteria (number of general bacteria, colon bacillus, fungus) depending on each workplace, number of microorganism of internal packing room, seasoning fluid processing room, washing room and storage room was detected to be 10 CFU/Plate, 2 CFU/Plate, 60 CFU/Plate and 20 CFU/Plate, respectively. As a result of testing palm condition of workers, as number of general bacteria and colon bacillus was represented to be high as 346 $CFU/Cm^2$ and 23 $CFU/Cm^2$, respectively, an education and training for individual sanitation control was considered to be required. As a result of inspecting surface pollution level of manufacturing facility and devices, colon bacillus was not detected in all the specimen but general bacteria was most dominantly detected in PP Packing machine and Siuping machine (PE Bulk) as $4.2{\times}10^3CFU/Cm^2$, $2.6{\times}10^3CFU/Cm^2$, respectively. As a result of analyzing above hazardous factors, processing process of seasoning fluid where pathogenic bacteria may be prevented, reduced or removed is required to be controlled by CCP-B (Biological) and threshold level (critical control point) was set at pH 3-4. Therefore, it is considered that thorough HACCP control plan including control criteria (point) of seasoning fluid processing process, countermeasures in case of its deviation, its verification method, education/training and record control would be required.