• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.232.1-232
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• 1999

No Abstract, See Full Text

• International Journal of Air-Conditioning and Refrigeration
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• v.14 no.3
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• pp.118-123
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• 2006

A few commonly used correlation equations of the enthalpy of vaporization essential to the analysis of refrigeration cycles are reviewed. A new four-parameter correlation equation is proposed assuming that the enthalpy of vaporization could be represented with a linear form of the temperature and an additional function which slowly decreases as the temperature increases. It is not a common practice to measure the enthalpy of vaporization by experiment; therefore, performance of the new correlation is examined using numeric data from the ASHRAE tables for 22 pure substance refrigerants. The new correlation equation and other existing ones are fitted to the data optimizing the root mean squared deviation. All data points are weighted equally and NBP (normal boiling point) is used as a fixed point since the NBP is important for refrigeration application. The new four-parameter equation yields an average absolute deviation of 0.05% for 22 refrigerants which is smaller than those of other four-parameter equations, such as Guermouche-Vergnaud (0.08%), Aerebrot (0.13%), Radoz-Lyderson (0.08%), and Somayajulu four-parameter equation (0.08%).

• Journal of Environmental Health Sciences
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• v.27 no.2
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• pp.43-50
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• 2001

This paper reviews the results of a series of efforts to develop structure-activity models for slow-reacting chemicals and olefins whose toxicity may be enhanced by the ultraviolet radiation. Photoinduced toxicity of 14 compounds was found to be a different result of competing factors of structure, having carbon-carbon double bonds. To mimic the biological consequences of photooxidative damage in mammalian cells, the photochemical mutagenicith of 14 chemicals was tested in the CAS. Simple olefins were photochemically mutagenic or carcinogenic with irradiation, increasing the alkylating activity from zero level to 0.87(abs/gram) for styrene, 0.25 for 1-butene, 0.11 for 1-hexene, respectively, whereas no photochemical mutagenicity was observed with 1-octene in the absence of the CAS. Oxide compounds, however, showed a decreasing trend of photoalkylating activities in the presence or absence of the CAS. We found that the structure-activity relationship was not applicable to our data.

• Korean Chemical Engineering Research
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• v.43 no.4
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• pp.458-466
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• 2005

Full-scale utilizations of batch separation process often require knowledge about thermodynamics and correlation techniques of physical properties of complex mixture consisting of a great number of many unknown components. Various empirical correlations have been proposed to predict the physical properties mostly about the pseudocomponent of petroleum. In this study, one parameter correlations are developed for the calculations of the critical physical properties and ideal heat capacity of the pseudo-component of coal tar fractions. Developed model can provide a tool for the design and operations for the batch distillation of coal tar mixture.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.2
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• pp.397-404
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• 2018

As the usage of internet is increasing, a lot of user behavior are written in a log file and the researches and industries using the log files are getting activated recently. This paper uses the Hadoop based on open source distributed computing platform and proposes a customized tourism system by analyzing user behaviors in the log files. The proposed system uses Google Analytics to get user's log files from the website that users visit, and stores search terms extracted by MapReduce to HDFS. Also it gathers features about the sight-seeing places or cities which travelers want to tour from travel guide websites by Octopus application. It suggests the customized cities by matching the search terms and city features. NBP(next bit permutation) algorithm to rearrange the search terms and city features is used to increase the probability of matching. Some customized cities are suggested by analyzing log files for 39 users to show the performance of the proposed system.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1945-1950
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• 2004

In this paper, The performance of Kim-Chi refrigerator with three evaporator and one compressor was investigated in employing 55% propane and 45% isobutane (R290/R600a) refrigerant mixture as an alternative refrigerant of R134a. The drop in test was performed by varying both refrigerant charge amount and capillary tube length in order to find both the performance and reliability of a small multi-refrigeration system. As a result, Both the power consumption and COP is increased by about 15% and 10%, respectively as compared to the baseline R134a system. In addition, the propane/isobutene refrigerant mixture system took advantage of the minimization of modification and redesigning of system components because of similar thermodynamic properties with R134a such as saturation pressure, temperature, normal boiling point(NBP) characteristics

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2015.08a
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• pp.102-106
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• 2015

• The korean journal of orthodontics
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• v.33 no.3 s.98
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• pp.185-197
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• 2003

This study was performed to identify the characteristics of the OFC1 gene (locus: chromosome 6p24.3) in Korean patients, which is assumed to be the major gene behind the nonsyndromic cleft lip and palate. The sample consisted of 80 subjects: 40 nonsyndromic cleft lip and palate patients (proband, 20 males and females, mean age 14.2 years); and 40 normal adults (20 males and 20 females, mean age 25.6 years). Using PCR-based assay, the OFC1 gene was amplified, sequenced, and then searched for similar protein structures. Results were as follows: 1. The OFC1 gene contains the microsatellite marker 'CA' repeats. The number of the reference 'CA' repeats was 21 times, and formed as TA(CA)11TA(CA)10. But, in Koreans, the number of tandem 'CA' repeats was varied from 17 to 26 except 18, and 'CA' repeats consisted of TA(CA)n. 2. Nine allelic variants were found. Distribution of the OFC1 allele was similar between the patients and control group. 3. There was a replacement of the base 'T' to 'C' after 11 tandem 'CA' repeats in Koreans compared with Weissenbach's report. However, the difference did not seem to be the ORF prediction results between Koreans and Weissenbach's report. 4. The BLAST search results showed the Telomerase reverse transcriptase (TERT) and the Nucleotide binding protein 2 (NBP2) as similar proteins. The TERT was a protein product by the hTERT gene in the locus 5p15.33 (NCBI Genome Annotation; NT023089) The NBP2 was a protein product by the ABCC3 (ATP-binding cassette, sub-family C) gene in the locus 17q22 (NCBI Genome Annotation; NT010783). 5. In the Pedant-Pro database analysis, the predictable protein structure of the OFC1 gene had at least one transmembrane region and one non-globular region.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.779-782
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• 2005

Cell-free expression is a powerful tool for rapid protein analysis, enabling an efficient identification of gene without cumbersome procedure of transformation and cell culture. Epoxide hydrolase (EH) gene of Rhodotorula glutinis was simply amplified by PCR, and the resultant gene was expressed in vitro using a coupled Transcription/translation system. The cell-free expressed EH protein mixture exhibited the enantioselective hydrolysis activity toward (R)-styrene oxide, representing that cell-free protein synthesis system can be used for the rapid expression of an enantioselective enzyme for an efficient identification of the chiral activity.

• Advances in materials Research
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• v.4 no.3
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• pp.145-164
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• 2015

Biodegredable and injectable nanocomposites based on polypropylene fumarate (PPF) as unsaturated polyester were prepared. The investigated polyester was crosslinked with three different monomers namely N-vinyl pyrrolidone (NVP), methyl methacrylate (MMA) and a mixture of NVP and MMA (1:1 weight ratio) and was filled with 45 wt% of hydroxyapatite (HA) incorporated with different concentrations of chemically treated natural bone powder (NBP) (5, 10 and 15 wt%) in order to be used in treatment of orthopedics bone diseases and fractures. The nanocomposites immersed in the simulated body fluid (SBF) for 30 days, after the period of immersion in-vitro bioactivity of the nanocomposites was studied through Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy dispersive X-ray (EDX) in addition to dielectric measurements. The degradation time of immersed samples and the change in the pH of the SBF were studied during the period of immersion.