• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.1
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• pp.101-108
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• 2008

This study is to examine bond strength of beam reinforced with GFRP rebar under 4-point fatigue bending test by adopting BRITISH STANDARD. The variables were made to have bonding length of 5times(5db), and 15times(15db) of the nominal diameter of GFRP rebar and were done to analyze the relationship between the bonding strength and the slip. In the result of the test, pull-out failure was dominant in the 5db specimen, patterns of the pull-out failure and concrete shear failure appeared in the 15db specimen showed only concrete shear failure at the end of bonding length. Therefore, The strain development consist of three different stage : A rapid increases form 0 to about 10% of total fatigue life. A uniform increases form 10% to about 70%~90%. Then a rapid increases until failure, if failure takes place. It seems that stress level has not influence on the secant modules of elasticity. And also according to the outcome the existing strengthening method came out to be the most superiority in S-N graphs.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1194-1202
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• 2012

Remotely sensed satellite images can be applied to monitor and obtain land surface information on inaccessible areas. We classified paddy field area in North Korea based on on-screen digitization with visual interpretation using 291 RapidEye satellite images covering the whole country. Criteria for paddy field classification based on RapidEye imagery acquired at different time of rice growth period was defined. Darker colored fields with regular shape in the images with false color composite from early May to late June were detected as rice fields. From early July to late September, it was hard to discriminate rice canopy from other type of vegetation including upland crops, grass, and forest in the image. Regular form of readjusted rice field in the plains and uniform texture when compared with surrounding vegetation. Paddy fields classified from RapidEye imagery were mapped and the areas were calculated by administrative district, province or city. Sixty six percent of paddy fields ($3,521km^2$) were distributed in the west coastal regions including Pyeongannam-do, Pyeonganbuk-do, and Hwanghaenam-do. The paddy field areas classified from RapidEye images showed less than 1% of difference from the paddy field areas of North Korea reported by FAO/WFP (Food and Agriculture Organization/World Food Programme).

• The Korean Journal of Archival Studies
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• no.11
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• pp.181-214
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• 2005

Metropolitan rapid transit system plays an essential role in the public transportation system of any large city, and its managing agency is usually charged with the responsibility of storing and managing the design drawings of the system. The drawings are important and historically valuable documents that must be kept permanently because they contain comprehensive data that is used to manage and maintain the system. However, no study has been performed in Korea on how well agencies are preserving and managing these records. Seoul Metropolitan Rapid Transit Corporation(SMRT) is the managing agency established by the city of Seoul to operate subway lines 5, 6, 7, and 8 more efficiently to serve its citizens. By the Act on Records Management in Public Institutions(ARMPI), SMRT should establish a records center to manage its records. Furthermore, all drawings produced by SMRT and other third party entities should be in compliance with the Act. However, SMRT, as a form of local public corporation, can establish a records center by its own way. Accordingly, the National Archives & Records Service(NARS) has very little control over SMRT. Therefore, the purpose of this study is to research and analyze the present state of storage and management of the drawings of metropolitan rapid transit in SMRT and is to find a desirable method of preservation and management for drawings of metropolitan rapid transit. In the process of the study, it was found that a records center is being considered to manage only general official documents and not to manage the drawings as required by ARMPI. SMRT does not have a records center, and the environment of management on the drawings is very poor. Although there is a plan to develop a new management system for the drawings, it will be non-compliant of ARMPI. What's happening at SMRT does not reflect the state of all other cities' metropolitan rapid transit records management systems, but the state of creation of records center of local public corporation is the almost same state as SMRT. There should be continuous education and many studies conducted in order to manage the drawings of metropolitan rapid transit efficiently by records management system. This study proposes a records center based on both professional records centers and union records centers. Although metropolitan rapid transit is constructed and managed by each local public corporation, the overall characteristics and processes of metropolitan rapid transit projects are similar in nature. In consideration of huge quantity, complexity and specialty of drawings produced and used during construction and operation of metropolitan rapid transit, and overlap of each local public corporation's effort and cost of the storage and management of the drawings, they need to be managed in a professional and united way. As an example of professional records center, there is the National Personnel Records Center(NPRC) in St. Louis, Missouri. NPRC is one of the National Archives and Records Administration's largest operations and a central repository of personnel-related records on former and present federal employees and the military. It provides extensive information to government agencies, military veterans, former federal employees, family members, as well as researchers and historians. As an example of union records center, there is the Chinese Union Dangansil. It was established by several institutions and organizations, so united management of records can be performed and human efforts and facilities can be saved. We should establish a professional and united records center which manages drawings of metropolitan rapid transit and provides service to researchers and the public as well as members of the related institutions. This study can be an impetus to improve interest on management of not only drawings of metropolitan rapid transit but also drawings of various public facilities.

• Archives of design research
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• v.19 no.1 s.63
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• pp.263-272
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• 2006

People's values as well as their behavioral form of using a product are changing due to the rapid introduction of diverse cultures and the Five-day workweek system. The single and the married are the subjects of this study: it is aimed to evaluate and analyze, thus grasping their difference in behavioral form of using a washing machine, the main factors they consider to be important when purchasing one, and the level of satisfaction they get from their own washers. A questionnaire was used as a tool for a better Factor Analysis and Frequency Analysis research. There were 6 essential factors which unmarried people take into consideration when purchasing a washer: economical efficiency, measure of capacity, design, type, brand and advertising, function. On the other hand, economical efficiency, convenience, measure of capacity, function, and type was what the married thought would be the 6 central factors.

• Journal of Technologic Dentistry
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• v.37 no.1
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• pp.23-29
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• 2015

Purpose: The selective laser melting (SLM) process for dentistry, which is one of the additive manufacturing technologies (AM) allows for rapid production of a three-dimensional model with complex shape by directly melting metal powder. This process generates detailed items of a three-dimensional model shape through consolidation of a thin powder layer by utilizing both selective melting and laser beam simultaneously. In regard to SLM process, Fe-base powder, Ti-6AI-4V powder, AI-base powder, etc. have been researched. It is believed that the aforementioned technologies will be widely utilized in manufacturing metal parts using metal powder of raw material. This study chose Ni-Cr-Mo metal powder in order to manufacture metal powder materials that would be used in the selective laser melting for dentistry. Methods: This study manufactured metal powder using mechanical alloying technique (MA) among those metal powder manufacturing techniques. Moreover, this study aimed to utilize the metal powder manufactured after observing the characteristics of powder as preliminary data of Ni-Cr-Mo metal powder. This study could obtain the following conclusions within the experimental limitations. Results: As a result of mechanically alloying Ni-Cr-Mo powder over time, its mean particle size was $66.93{\mu}m$ $54.4{\mu}m$ and $45.39{\mu}m$ at 10h, 20h and 30h, respectively. The gtain form of metal powder by mechanical alloying technique was a sponge-like shape of irregular plate; however, the gtain form manufactured by high-pressure water aromization process had the following three types: globular type, chain type and oval type. Conclusion: This study found $37.65{\mu}m$ as the mean particle size of Ni-Cr-Mo metal powder, which was manufactured using water atomization technique under the following conditions: water atomization flux of 300 liter/min, hydraulic pressure of $400kgf/cm^2$ and injection angle of $45^{\circ}$. This study confirmed that the grain form of powder (solid particle form) would vary depending on the manufacturing process.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.725-731
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• 1998

Nine crossbred female pigs fitted with the bladder catheters were used to investigate the effects of dietary protein form on the efficiency of absorbed nitrogen for nitrogen retention in growing pigs. Combinations of the main protein sources were corn-soybean meal (CSM; slow + slow absorption rate form), corn-hydrolyzed casein (CAS; slow + rapid absorption rate form) and corn-porcine plasma (CPL; slow + intermediate absorption rate form). All experimental diets were formulated to be isonitrogenous (CP 11%) and isocaloric (3.5 Mcal/kg) and synthetic amino acids were added to the diet as required to maintain an equivalent amino acid profile among diets. Fecal digestibility of nitrogen was not different among treatments (p > 0.10). Ingested nitrogen was absorbed with an apparent efficiency of 82% to 84%. Mean nitrogen retention in pigs fed the CSM diet was as high as for pigs fed the CPL diet (0.74 g N/kg $BW^{0.75}$ per d), which was higher than the N retention rate in pigs fed CAS diet (0.68 g/kg $BW^{0.75}$ per d; P < 0.05). Apparent biological values (ABV = 100 ${\times}$ N retention/absorbed nitrogen) were 63.3%, 58.0% and 61.6% for CSM, CAS, and CPL groups, respectively (p < 0.05). There was no difference in mean energy digestibility among treatments. The efficiency of absorbed lysine utilization was significantly different among treatments (p < 0.05). Pigs fed the CAS diet were inferior to counterparts on the other diets in utilizing absorbed lysine. The ratios of free (and small peptide-bound) to protein-bound amino acids in CSM diet differed considerably from the CAS diet. This may affect the efficiency of amino acids utilization for nitrogen retention if hydrolyzed and intact amino acid pools reach the blood at different times.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.3
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• pp.87-95
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• 2008

The purpose of this study is to provide a decision support to select an appropriate rapid prototyping(RP) machine that suits the application of a part. Selection factors include concept model, form/fit/functional model, pattern model for molding, material property, build time and part cost that greatly affect the performance of RP machines. However, the selection of a RP is not an easy decision because they are uncertain and vague. For this reason, the aim of this research is to propose hybrid multiple attribute decision making approaches to effectively evaluate RP machines. In addition, because subjective considerations are relevant to selection decision, a fuzzy logic approach is adopted. The proposed selection procedure consists of several steps. First, we identify RP machines that the users consider. After constructing the evaluation criteria, we calculate the weights of the criteria by applying the fuzzy Analytic Hierarchy Process(AHP) method. Finally, we construct the fuzzy Technique of Order Preference by Similarity to Ideal Solution(TOPSIS) method to achieve the ranking order of all machines providing the decision information for the selection of RP machines.

• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.549-552
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• 2004

A sensitive, selective and rapid method has been developed for the determination of mercury based on the rapid reaction of mercury(II) with p-sulfobenzylidenethiorhodanine (SBDTR) and the solid phase extraction of the colored chelate with $C_{18}$ disks. In the presence of pH 3.5 sodium acetate-acetic acid buffer solution and Emulsifier-OP medium, SBDTR reacts with mercury(II) to form a red chelate of a molar ratio 1 : 2 (mercury to SBDTR). This chelate was prconcentrated by solid phase extraction with $C_{18}$ disks. An enrichment factor of 50 was achieved. The molar absorptivity of the chelate is $1.28{\times}10^5 L{\cdot}mol^{-1}{\cdot}cm^{-1}$ at 545 nm in measured solution. Beer's law is obeyed in the range of 0.01-3 ${\mu}$g/mL. The relative standard deviation for eleven replicates sample of 0.01 ${\mu}$g/mL is 1.65%. This method was applied to the determination of mercury in tobacco and tobacco additive with good results.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.263-266
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• 2004

A sensitive, selective and rapid method has been developed for the determination ${\mu}$g/L level of vanadium ion based on the rapid reaction of vanadium(V) with 2-(2-quinolylazo)-5-diethylaminophenol (QADEAP) and the solid phase extraction of the colored chelate with $C_{18}$ cartridge. The QADEAP reacts with V(V) in the presence of citric acid-sodium hydroxide buffer solution (pH = 3.5) and cetyl trimethylammonium bromide (CTMAB) medium to form a violet chelate of a molar ratio 1 : 2 (V(V) to QADEAP). This chelate was enriched by solid phase extraction with $C_{18}$cartridge and the enrichment factor of 50 was obtained by elution of the chelates from the cartridge with ethanol. The molar absorptivity of the chelate is $1.28 {\times}10^5L\;mol^{-1}cm^{-1}$ at 590 nm in the measured solution. Beer's law is obeyed in the range of 0.01-0.6 ${\mu}$g/mL. The detection limit is 0.04 ${\mu}$g/L in the original samples. This method was applied to the determination of vanadium(V) in water and biological samples with good results.

• BMB Reports
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• v.32 no.3
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• pp.273-278
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• 1999

Cytolysin produced by Vibrio vulnificus has been known to be lethal to mice by increasing vascular permeability and neutrophil sequestration in the lung. In the present study, a cytotoxic mechanism of V. vulnificus cytolysin on the neutrophil was investigated. Cytolysin rapidly bound to neutrophils and induced cell death, as determined by the trypan blue exclusion test. V. vulnificus cytolysin caused the depletion of cellular ATP without the release of ATP or lactate dehydrogenase. Formation of transmembrane pores was evidenced by the rapid efflux of potassium and 2-deoxy-D-[$^3H$]glucose from cytolysin-treated neutrophils. It was further confirmed by the rapid flow of monovalent ions in the patch clamp of cytolysin-treated neutrophil membrane. The pore formation was accompanied by the oligomerization of cytolysin monomers on the neutrophil membrane as demonstrated by immunoblot, which exhibited a 210 kDa band corresponding to a tetramer of the native cytolysin of $M_r$ 51,000. These findings indicate that V. vulnificus cytolysin rapidly binds to the neutrophil membrane and oligomerizes to form small transmembrane pores, which induce the efflux of potassium and the depletion of cellular ATP leading to cell death without cytolysis.