• Journal of IKEEE
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• v.10 no.1 s.18
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• pp.49-54
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• 2006

Recently, e-mail has become an important way of communications in IT societies, but it creates various social problems due to increase of spam mails. Even though many organizations and cooperation have been trying researches to develop spam mail blocking technologies, a lot of cost and system complexities are required because of varieties of spam blocking technologies. In this paper, we designed of the SMBC(Spam Mail Blocking Center) using the Fit FA(Filtering Algorithm) Finder. Fit-FA Finder that search and applises spam mail filtering algorithm of the most suitable confrontation according to type of spam mail. The system of spam mail filtering is decided performance of the system by procedure that spam filter is used. Go through designed Fit-FA Finder and reduced unnecessary filtering process and processing time and load than appointment order filter application way of existent spam mail interception system.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.295-300
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• 2009

Formaldehyde (FA) is an important irritant compound in pesticide to induce asthma and allergy in respiratory system. Alveolar macrophage is also an pivotal cell in the immune response of respiratory system. However, the effect of FA in macrophage cell viability has not been elucidated. Thus, this study was conducted to investigate the effect of FA on apoptosis in Raw 264.7 cells, alveolar macrophage cell line. In this study, FA decreased cell viability of lung alveolar macrophage cells in a dose-dependent manner (>$100{\mu}M$). FA-induced decrease of cell viability was blocked by the treatment of antioxidants (vitamin C, NAC, and catalase). Indeed, FA induced lipid peroxide formation in Raw 264.7 cells. FA decreased Bcl-2 expression but increased Bax expression in lung alveloar macrophage cells. In addition, FA also increased the cleaved form of caspase-3. In conclusion, FA induced apoptosis via oxidative stress in cultured Raw 264.7 cells.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.102-108
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• 2004

The present experiment was conducted to assess the efficacy of methionine hydroxy analogue free fatty acid (MHAFA) in comparison to DL-methionine (DL-Met) utilizing day-old commercial broiler chicks (n=300). The chicks were randomly distributed into 30 groups of 10 chicks each. Three dietary treatments, viz. D1-maize-soybean meal based basal diet (Control), D2- control diet supplemented with DL- methionine to meet its requirements and D3-control supplemented with MHA-FA @ 1.54 times of DL-methionine used in D2, were formulated. Each dietary treatment was offered to 10 replicated groups of chicks following completely random design (CRD). The chicks fed on supplemental DL-Met had significantly higher (p<0.01) gain in body weight, followed by MHA-FA group and control during 0-3 weeks of age. During overall growth period (0-6 weeks), chicks in DL-Met and MHA-FA groups grew better (p<0.01) than those in control. Feed conversion ratio (FCR) improved (p<0.01) on supplementation of either DL- Met or MHA-FA in the basal (Control) diet during 0-3 weeks of age. The FCR for overall period, however, did not differ statistically (p>0.05) amongst the treatments. The eviscerated yields emanated from diets with DL-Met or MHA-FA were higher (p<0.01) than that in Control. Abdominal fat pad was also more (p<0.01) in broilers fed control diet than in DL-Met or MHA-FA supplemented group. Breast yield was higher (p<0.05) in MHA-FA fed broilers than those fed DL-methionine supplemented or un-supplemented diets. The efficacy of MHA-FA in comparison to DL-Met for growth was 62.11, 64.82 and 63.88% and for feed efficiency was 62.98, 67.73 and 64.01% at 0-3, 3-6 and 0-6 weeks of age, respectively, while it was 65.85, 71.40 and 67.49% for eviscerated yield, abdominal fat pad reduction and breast yield at 6 weeks of age, respectively.

• Journal of Internet Computing and Services
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• v.5 no.1
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• pp.25-32
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• 2004

Mobile computing environment makes it possible for computing activities to be maintained during movement even if a user changes its network point of attachment. Mobile IP is a standard protocol designed to be used in such mobile computing environment. However, Mobile IP has a drawback to incur a lot of handoff delays and waste network resources, since CoA(Care of Address) registration packets need to go through a HA(Home Agent) first whenever a mobile node moves. To solve this long-standing problem, this paper proposes a new scheme that, for infra-domain movement, efficiently performs local handoff without notifying the HA Specifically, based on the notion of load balance, the proposed scheme allows every FA(Foreign Agent) in a domain to become the root FA(also known as domain FA) dynamically, thus distributing the registration task into many other foreign agents. The dynamic root assignment through load balancing ultimately leads to fast network response due to less frequent transmission of registration packets.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.889-892
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• 2008

This study, having combined and displaced fly ash known as admixture material that delays hydration reaction with coarse particle cement("CC" hereinafter) collected in particle classification method during ordinary portland cement("OPC" hereinafter), reviewed the hydration heat characteristics affecting the concrete. To reduce hydration heat, the study plain-mixed which used 100% OPC for WB 50% level 1, displaced CC at level 3 of 25%, 50% and 75% for OPC, and by displacing FA with admixture material at level 5 of 0%, 10%, 20%, 30% and 40%, experimented totally 16 batches. As a result of experiment, in the case of flow, the more CC displacement rate increased, the more it tended to decrease, and the more FA displacement rate increased, the more it decreased. As for simple adiabatic temperature rise by the CC and FA displacement rates, it decreased as displacement rate increased, and particularly in the case of FA40, temperature rise amount, $5.8{\sim}7.4^{\circ}C$, was very low. Compressive strength decreased in proportion to displacement rate, however strength reduction increment was shown to decrease with age progress.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.12 s.354
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• pp.89-94
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• 2006

In the Mobile IP, the movement of Mobile Host(MH) causes packets to be transmitted through a long route. A Correspond Node(CN) first communicate with a Home Agent(HA) when a Mobile Host moved from one subnet to another subnet. The HH-MIP algorithm reduces an inefficient transmission of packets by regarding a Foreign Agent(FA) near a mobile host as a Temporary Home Agent(THA). However, The algorithm costs the unnecessary signaling by measuring the distance of route between a FA and a THA for handover in the case that a Mobile host comes from a THA which a current FA never communicated. To solve this problem, we propose a scheme called Hierarchical Home Agent Handover in Mobile IP(HHH-MIP) algorithm. Our HHH-MIP algorithm only searches tables in a router by using the hierarchical structure between a FA and a THA. The simulation results show that the HHH-MIP algorithm reduces the additional signaling cost.

• Journal of the Korean Institute of Gas
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• v.8 no.2 s.23
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• pp.1-7
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• 2004

The physical properties of rigid polyurethane foam(PUF) synthesized using various types of blowing agents such as water, HFC-365mfc, HFC-245fa, HCFC-l4lb, CFC-11 and n-pentane were studied. The blending effect of blowing agents were also studied. The thermal conductivity, reaction rate, and cell morphology of the PUF with various blending ratio of blowing agents were investigated. The PUF blown by water shows the highest compressive strength among other single blowing agents. The thermal conductivity of PUFs blown by HFC-245fa and HFC-365mfc are close to that of PUFs blown by CFC-11. When HFC-365mfc was mixed with HFC-245fa(30mo1e$\%$) as coblowing agent, the mechanical property shows the highest value among other coblowing agents. It is that the thermal conductivity of PUFs depends on cell size of PUFs as well as thermal conductivity of blowing agent in gaseous form.

• Journal of Digital Convergence
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• v.19 no.8
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• pp.275-283
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• 2021

This study was intended to help improve assessment in college EFL classes by examining the relationship between formative assessment (FA) and summative assessment (SA). Participants for the study were 75 undergraduates, taking an eight-week optional college English course at a four-year college in China. FA data were collected in the final course of the course by a self-reporting survey using the online training platform Mosoteach. To achieve the finding, the relationship between FA scores and SA scores (final exam and performance scores) was analyzed in SPSS by means of Pearson correlation analyses. Significant positive correlations were found between FA and SA scores overall. In addition, students' performance on chapter tests, online discussions, brainstorming, quick-responses, assignments and the number of thumbs-up clicks by teachers were significantly correlated with SA scores. The results suggested that FA administered through the Mosoteach app could improve students' academic performance, thus providing an empirical basis for improving educational assessment. Based on these findings, implications for assessment in EFL classes were described.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.8
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• pp.555-562
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• 2007

In this study, condensation heat transfer coefficients (HTCs) of R22, R134a, R245fa and R123 are measured on a horizontal plain tube. All data are taken at the vapor temperature of $39^{\circ}C$ with a wall subcooling temperature $3-8^{\circ}C$. Test results show the HTCs of newly developed alternative low vapor pressure refrigerant, R245fa, on a plain tube are 9.5% higher than those of R123 while they are 3.3% and 5.6% lower than those of R134a and R22 respectively. Nusselt's prediction equation for a plain tube underpredicts the data by 13.7% for all refrigerants while a modified equation yielded 5.9% deviation against all data. From the view point of environmental safety and condensation heat transfer, R245fa is a long term good candidate to replace R123 used in centrifugal chillers.

• Journal of Environmental Health Sciences
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• v.34 no.5
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• pp.387-394
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• 2008

The toxicity of methyl tert-butyl ether (MTBE), tert-butyl alcohol (TBA) and formaldehyde (FA) on the indigenous microbial community in forest soil was studied. MTBE, TBA and FA with different concentrations were added into microcosms containing forest soil samples. After 10 and 30 days, total viable cell number and dehydrogenase activity in the microcosms were evaluated. Bacterial communities in the microcosms were also analyzed using a denaturing gradient gel electrophoresis (DGGE). Dehydrogenase activity and total viable cell number were decreased according to the increase of MTBE, TBA and FA concentrations (P<0.05). FA toxicity was the highest, but TBA toxicity was the lowest. The results of principal component analysis using DGGE fingerprints showed that the microbial communities contaminated MTBE, TBA and FA were grouped by exposure time not exposure concentration. Dominant species in the microcosms were as follows: Photobacterium damselae sub sp. and Bacillus sp. KAR28 for MTBE; Mycobacterium sp. and Uncultured Clostridium sp. for TBA; and Uncultured Paenibacillaceae bacterium and Anxynobacillus, Flavithermus for FA.