• Journal of the Korean Chemical Society
• /
• v.30 no.4
• /
• pp.389-393
• /
• 1986

The reaction of 2,5-hexanedione with a variety of primary amines using tetracarbonylhydridoferrate(O) as a selective reducing agent at room temperature or 60${\circ}C$ under an atmosphere of carbon monoxide gave the corresponding N-substituted 2,5-dimethylpyrrolidine derivatives. The reaction of synthesized 5-nitro-2-hexanone with benzaldehyde in the presence of tetracarbonylhydridoferrate(O) at 150${\circ}C$ under an atmosphere of carbon monoxide in an autoclave also gave N-benzyl-2,5-dimethylpyrrolidine in moderate yield. The mechanism of these reactions was investigated.

• Elastomers and Composites
• /
• v.50 no.4
• /
• pp.245-250
• /
• 2015

Recycling of ethylene-propylene-diene terpolymer (EPDM) scrap was tried by blending with polypropylene (PP). EPDM scrap powder was prepared by shear pulverization process at high temperature, which may lead to selective chain scission induced by difference in the critical elastic coefficient. On the other hand, EPDM scrap powder was prepared by adding a selected reclaiming agent during shear pulverization process at high temperature. Terpene as a bonding agent was then introduced to improve adhesion property. PP, used as a matrix for manufacturing thermoplastic elastomer, was modified by the incorporation of dicumyl peroxide and maleic anhydride. The functionalized EPDM and modified PP were blended and cured dynamically at $190^{\circ}C$. The blend materials prepared in this study showed the comparable results to those of conventional TPE in terms of tensile and flow properties. Also, the odor component of recycled EPDM was analyzed using GC-MS.

• Microbiology and Biotechnology Letters
• /
• v.47 no.4
• /
• pp.651-661
• /
• 2019

Targeting the pathogen viability using drugs is associated with development of drug resistance due to selective pressure. Hence, there is an increased interest in developing agents that target bacterial virulence. In this study, the inhibitory effect of ciclopirox, an antifungal agent with iron chelation potential, on the microbial virulence factors was evaluated in 26 clinical MDR Pseudomonas aeruginosa isolates collected from Alexandria Main University Hospital, a tertiary hospital in Egypt. Treatment with 9 ㎍/ml ciclopirox inhibited the hemolytic activity in 70% isolates, reduced pyocyanin production, decreased protease secretion in 46% isolates, lowered twitching and swarming motility, and decreased biofilm formation by 1.5- to 4.5-fold. The quantitative real-time PCR analysis revealed that treatment with ciclopirox downregulated the expression levels of alkaline protease (aprA) and pyocyanin (phzA1). Ciclopirox is used to treat hematological malignancies and the systemic administration of ciclopirox is reported to have adequate oral absorption with a satisfactory drug safety profile. It is important to calculate the appropriate clinical dose and therapeutic index to reposition ciclopirox from a topical antifungal agent to a promising virulence-modifying agent agent against P. aeruginosa, a problematic Gram-negative pathogen.

• Journal of Korea Game Society
• /
• v.7 no.4
• /
• pp.93-104
• /
• 2007

In the complex real-time multi-agent system such as game environment, dynamic task allocations are repeatedly performed to achieve a goal in terms of system efficiency. In this research, we present a task allocation scheme suitable for the real-time multi-agent environment. The scheme is to optimize the task allocation by complementing existing coordination agent with $A^*$ algorithm. The coordination agent creates a status graph that consists of nodes which represent the combinations of tasks and agents, and refines the graph to remove nodes of non-execution tasks and agents. The coordination agent performs the selective utilization of the $A^*$ algorithm method and the greedy method for real-time re-allocation. Then it finds some paths of the minimum cost as optimized results by using $A^*$ algorithm. Our experiments show that the coordination agent with $A^*$ algorithm improves a task allocation efficiency about 25% highly than the coordination agent only with greedy algorithm.

• Journal of The Korean Society of Integrative Medicine
• /
• v.8 no.4
• /
• pp.79-92
• /
• 2020

Purpose : The purpose of this study was to evaluate the prescription pattern of NSAIDs and GPAs in the arthritis patients over 65 years old to prevent the GI adverse events. Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most commonly used agents to treat arthritis, can cause gastrointestinal (GI) adverse effects. Recent guidelines recommend that moderate risk patients who have one or two risk factors, should be prescribed either combination of non-selective NSAID (nsNSAIDs) and gastroprotective agent (GPAs) or selective NSAID alone. Methods : Study population was National Patient Sample of 2011. Number of drugs used were 138 for NSAIDs and 21 for GPAs. Chi-square test was used to compare prescribing patterns. Results : The appropriate prescription rate follows the guideline was 11.2%: co-prescription with nsNSAID and proton pump inhibitor (PPI) or misoprostol was 1.6% and selective NSAID alone was 9.6%. Inappropriate prescription rates were as follows: co-prescription with nsNSAID and Histamine-2 receptor antagonist (H2RA) or antiacid was 53.8% and nsNSAID alone was 35.0%. The appropriate prescription rate among the types of medical institute was 54.4% in tertiary hospital, 31.2% in secondary hospital, and 6.0% in primary hospital. The appropriate prescription rate among the regions was 19.4%, highest in Seoul and 4.2%, lowest in Jeju. The appropriate prescription rate among the medical departments was as follow: 12.2% in orthopaedic surgery, 11.0% in internal medicine, and 7.7% in other departments. Conclusion : This finding suggests the needs to revise the national medical insurance imbursement policy, provide continuing medical education about the guideline of medical doctors.

• Korean Journal of Clinical Pharmacy
• /
• v.27 no.4
• /
• pp.250-257
• /
• 2017

Objective: The prevalence rate of osteoarthritis in Koreans aged 50 years or older is 14.3%, and the total amount of medical costs is more than KRW 1 trillion. Recently, the reimbursement guidelines for osteoarthritis treatment have changed. Methods: In this study, we sought to describe prescription patterns of nonsteroidal anti-inflammatory drugs (NSAIDs) and gastro-protective agent (GPA) and analyze the clinical and economic impacts of the new policy using the national health insurance claims data. The incidence of upper gastrointestinal adverse event by policy change was identified through the odds ratio, and changes in medicine and medical costs related to osteoarthritis through mean and median. Results: There were 204,552 patients before the reimbursement guidelines relaxation and 239,710 after it, a 17.2% rise. The prescription ratio was 3.3% for the patients prescribed with COX-2 selective NSAIDs alone and 1.3% for those with both COX-2 selective NSAIDs and GPA combination before the reimbursement guidelines relaxation. The reimbursement guidelines relaxation significantly increased their ratios to 6.9% and 2.8%, respectively. Gastrointestinal adverse events significantly reduced by 1.21%p after reimbursement guidelines relaxation. The average medicine cost per person increased significantly to KRW 140,291 from KRW 137,323 after the reimbursement guidelines relaxation, while the average medical cost per person slightly decreased from KRW 311,605 to KRW 310,755 after the relaxation, showing no meaningful difference. Conclusion: The reimbursement guidelines relaxation may influence on decreasing the upper gastrointestinal adverse event, increasing the medicine costs and maintaining the medical costs for osteoarthritis.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.3B
• /
• pp.325-338
• /
• 2004

As the recent rapid development of internet technology and the wide spread of multimedia communication, massive increase of network traffic causes some problems such as the lack of network paths and the bad quality of service. To resolve these problems, this paper presents a traffic control agent that can perform the dynamic resource allocation by controlling traffic flows on a DiffServ network. In addition, this paper presents a router that can support DiffServ on Linux to support selective QoS in IP network environment. To implement a method for selective traffic transmission based on priority on a DiffServ router, this paper changes the queuing discipline in Linux, and presents the traffic control agent so that it can efficiently control routers, efficiently allocates network resources according to service requests, and relocate resources in response to state changes of the network. Particularly for the efficient processing of Assured Forwarding(AF) Per Hop Behavior(PHB), this paper proposes an ACWF$^2$Q$^{+}$ packet scheduler on a DiffServ router to enhance the throughput of packet transmission and the fairness of traffic services.s.

• Journal of the Korea Society of Computer and Information
• /
• v.22 no.1
• /
• pp.63-69
• /
• 2017

In this paper, we propose a method to optimize the geometry and installation position of the mixer in the selective catalytic reduction (SCR) system by computational fluid dynamic(CFD). Using the commercial CFD software of CFD-ACE+, the flow dynamics of the flue gas was numerically analyzed for improving the injection uniformity of the reduction agent. Numerical analysis of the mixed gas heat flow into the upstream side of the primary SCR catalyst layer was performed when the denitrification facility was operated. The characteristics such as the flow rate, temperature, pressure loss and ammonia concentration of the mixed gas consisting of the flue gas and the ammonia reducing gas were examined at the upstream of the catalyst layer of SCR. The temperature difference on the surface of the catalyst layer is very small compared to the flow rate of the exhaust gas, and the temperature difference caused by the reducing gas hardly occurs because the flow rate of the reducing gas is very small. When the mixed gas is introduced into the SCR reactor, there is a slight tendency toward one wall. When the gas passes through the catalyst layer having a large pressure loss, the flow angle of the exhaust gas changes because the direction of the exhaust gas changes toward a smaller flow. Based on the uniformity of the flow rate of the mixed gas calculated at the SCR, it is judged that the position of the test port reflected in the design is proper.

• 한국연소학회:학술대회논문집
• /
• 2006.04a
• /
• pp.79-85
• /
• 2006

In this study, to increase the mixing between flue gas and reducing agent, new shapes of $NH_3$ ejection nozzles are designed and experimentally and numerically tested. The nozzles have six holes perpendicular to the ambient flue gas flow and the tilting angle between direction of ambient flow and the hole axis is varied. To evaluate the mixing efficiency of the proposed nozzles, numerical and experimental tests are applied to several flow conditions comparing with single hole nozzle, which is commonly used in conventional SCR process. From the results the nozzle with tilted multi-holes has the large region of high turbulent intensity compared with conventional single hole nozzle. This is originated from the high vorticity near the upstream of the jet flow issuing from the hole. The high turbulent intensity and vorticity magnitude lead to enhanced mixing between flue gas and reducing agent. Hence, the most suitable moral ratio between NOx and reducing agent for the catalytic reaction can be obtained on behalf of the intensified scalar mixing within shorter physical mixing length.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.19 no.4
• /
• pp.17-32
• /
• 2006

Purpose : The aim of this study is to investigate the antibiotic effects of 14 herbs among blood-activating stasis-dispelling medicinals on vaginal microorganisms. Methods : Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus, Candida albicans, and Gardnerella vaginalis were used for vaginal pathogenic microorganisms. Lactobacillus gasseri, Streptococcus spp. and Escherichia coli HB101 were used for vaginal normal flora. The blood-activating stasis-dispelling medicinals, Mucunae Caulis, Salviae Radix, Persicae Semen, Myrrha, Zedoariae Rhizoma, Achuranthis Radix, Leonuri Herba, Melandrii Herba, Gleditsiae Spina, Lycopi Herba, Scirpi Rhizoma, Caesalpiniae Lignum, Corydlais Tuber and Polygoni Cuspidati Radix were used in this study. In vitro antibiotic activities were observed by optical density and colony test. Results : The optical density and colony test showed that Gleditsiae Spina, Scirpi Rhizoma, Corydlais Tuber, Polygoni Cuspidati Radix and Melandrii Herba of herbs among blood-activating stasis-dispelling medicinals had antimicrobial effect. Gleditsiae Spina had antimicrobial susceptibility and selective toxicity in Gardnerella vaginalis and MRSA. Scirpi Rhizoma had antimicrobial susceptibility and selective toxicity in Staphylococcus aureus and MRSA. Corydlais Tuber had antimicrobial susceptibility and selective toxicity in MRSA. Polygoni Cuspidati Radix had antimicrobial susceptibility and selective toxicity in Gardnerella vaginalis, Staphylococcus aureus and MRSA. Melandrii Herba had antimicrobial susceptibility and selective toxicity in Gardnerella vaginalis. Conclusion : According to the above results, we could suggest that Gleditsiae Spina, Scirpi Rhizoma, Corydlais Tuber, Polygoni Cuspidati Radix and Melandrii Herba of herbs among blood-activating stasis-dispelling medicinals be available to antimicrobial agent of vaginal pathogenic microbial species in vitro.