• Journal of Biosystems Engineering
• /
• v.32 no.3
• /
• pp.137-144
• /
• 2007

An anti-backlash gear was developed to reduce the rattle noise generated from the gearbox of a direct-engine PTO driveline of agricultural tractors under idling. A pair of gears using the anti-backlash gear as driven part was modeled and verified. Using the verified model, a computer simulation was conducted to investigate the effects of design parameters of the anti-backlash gear on the reduction of rattle noise. The optimum values of the design parameters were also determined by the computer simulation. The optimized anti-backlash gear was then manufactured and installed on the experimental PTO driveline for the performance test. Measurement of rattle noise was made to evaluate its performance before and after the driven gear of the PTO gearbox was replaced by the optimized anti-backlash gear. Results of the study were as follows: The optimum values of the design parameters, spring constant and deformation, may be determined by a relationship: $$k{\ge}\frac{4364.7}{150{\delta}-23.564}$$ The optimized anti-backlash gear reduced the rattle noise maximally by 16.9 dBA. This concluded that it would be most effective to use the optimized anti-backlash gear to eliminate the rattle noise in the PTO driveline.

• Natural Product Sciences
• /
• v.20 no.4
• /
• pp.301-305
• /
• 2014

The aim of our study is to investigate the anti-nociceptive and anti-inflammatory properties of an ethanol extract of the leaf and stem of Aralia cordata. Writhing responses induced by acetic acid, tail immersion test, and formalin-induced paw pain response for nociception and formalin-induced paw edema for inflammation were evaluated in mice. A. cordata (50 - 200 mg/kg, p.o.) and ibuprofen (100 mg/kg, p.o.), a positive non-steroidal anti-inflammatory drugs (NSAIDs), inhibited the acetic acid-induced writhing response, but they did not protect the thermal nociception in tail immersion test. However, morphine (5 mg/kg, s.c.) used as positive opioid control alleviated both the acetic acid-induced writhing response and thermal nociception in tail immersion test. In the formalin test, A. cordata (50 - 200mg/kg) and ibuprofen (200mg/kg) inhibited the second phase response (peripheral inflammatory response), but not the first phase response (central response), whereas morphine inhibited both phase pain responses. Both A. cordata (100 mg/kg) and ibuprofen (200 mg/kg) significantly alleviated the formalin-induced increase of paw thickness, the index of inflammation. These results show for the first time that the leaf and stem of A. cordata has a significant anti-nociceptive effect that seems to be peripheral, but not central. A. cordata also displays an anti-inflammatory activity in an acute inflammation model. The present study supports a possible use of the leaf and stem of A. cordata to treat pain and inflammation.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.29 no.5
• /
• pp.422-433
• /
• 2015

This study was conducted to investigate the anti-hyperlipidemic and anti-oxidative activities of Ikgihwaetang-gamibang (IK). We observed the effect of IK on lipid factor, inflammation factor, body weight and organ weight, and liver after administering IK to hyperlipidemia mice triggered by high fat diet. Additionally, we used Raw 264.7 cells to investigate the changes in anti-oxidative activity and the effects of anti-inflammation. Administration of IK resulted in reduction of total cholesterol, LDL cholesterol, TG, and glucose in blood serum while a clear increase in HDL cholesterol. The production of IL-1β and IL-6, and ROS and NO also decreased. The results showed that IK has anti-hyperlipidemic and anti-oxidative effects, and suggested its potential use in prevention and treatment of hyperlipidemia and its associated diseases.

• Journal of the military operations research society of Korea
• /
• v.6 no.2
• /
• pp.151-184
• /
• 1980

Simple models for a defense consisting of a preinstalled mine field possibly defended by an anti-tank weapon are derived and analyzed. This paper uses a special Poisson process to model the one or two positions of mines in the mine field. The duel between the anti-tank weapon and offensive tanks crossing the field is modeled with a continuous time Markov chain. Some algebraic solutions and numerical results are obtained for specific scenarios.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1996.04a
• /
• pp.11-18
• /
• 1996

We have established an air pouch-type allergic inflammation model in rats [1,2] and a peritoneal eosinophilia model in rats [3]. Employing the two models, chemical mediators and cytokines responsible for the development of inflammation induced by at allergic mechanisms are investigated to clarify the usefulness of the two models for the screening of anti-allergic inflammatory drugs.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.41 no.2
• /
• pp.74-83
• /
• 2018

It is very crucial activities that Korean army have to detect and recognize enemy's locations and types of weapon of their artillery firstly for effective operation of friendly force's artillery weapons during wartime. For these activities, one of the most critical artillery weapon systems is the anti-artillery radar (hereafter; radars) for immediate counter-fire operations against the target. So, in early wartime these radar's roles are very important for minimizing friendly force's damage because arbiters have to recognize a several enemy's artillery positions quickly and then to take an action right away. Up to date, Republic of Korea Army for tactical artillery operations only depends on individual commander's intuition and capability. Therefore, we propose these radars allocation model based on integer programming that combines ArcGIS (Geographic Information System) analysis data and each radar's performances which include allowable specific ranges of altitude, azimuth (FOV; field of view) and distances for target detection, and weapons types i.e., rocket, mortars and cannon ammo etc. And we demonstrate the effectiveness of their allocation's solution of available various types of radar asset through several experimental scenarios. The proposed model can be ensured the optimal detection coverage, the enhancement of artillery radar's operations and assisting a quick decision for commander finally.

• Nutrition Research and Practice
• /
• v.9 no.1
• /
• pp.3-10
• /
• 2015

BACKGROUND/OBJECTIVES: Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, involves chronic inflammation of the gastrointestinal tract. Previously, Sasa quelpaertensis leaves have been shown to mediate anti-inflammation and anti-cancer effects, although it remains unclear whether Sasa leaves are able to attenuate inflammation-related intestinal diseases. Therefore, the aim of this study was to investigate the anti-inflammatory effects of Sasa quelpaertensis leaf extract (SQE) using an in vitro co-culture model of the intestinal epithelial environment. MATERIALS/METHODS: An in vitro co-culture system was established that consisted of intestinal epithelial Caco-2 cells and RAW 264.7 macrophages. Treatment with lipopolysaccharide (LPS) was used to induce inflammation. RESULTS: Treatment with SQE significantly suppressed the secretion of LPS-induced nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), IL-6, and IL-$1{\beta}$ in co-cultured RAW 264.7 macrophages. In addition, expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and tumor necrosis factor (TNF)-${\alpha}$ were down-regulated in response to inhibition of $I{\kappa}B{\alpha}$ phosphorylation by SQE. Compared with two bioactive compounds that have previously been identified in SQE, tricin and P-coumaric acid, SQE exhibited the most effective anti-inflammatory properties. CONCLUSIONS: SQE exhibited intestinal anti-inflammatory activity by inhibiting various inflammatory mediators mediated through nuclear transcription factor kappa-B (NF-kB) activation. Thus, SQE has the potential to ameliorate inflammation-related diseases, including IBD, by limiting excessive production of pro-inflammatory mediators.

• Korean Journal of Veterinary Research
• /
• v.39 no.4
• /
• pp.715-723
• /
• 1999

Bee venom (BV) has been traditionally applied to relieve pain and to cure inflammatory diseases such as rheumatoid arthritis (RA) and neuritis. While several investigators have evaluated the anti-inflammatory effect of BV treatment, the anti-nociceptive effect of BV treatment on inflammatory pain is not reported. Therefore, we decided to evaluate the analgesic effect of BV treatment using Freund's adjuvant induced chronic arthritis model. Freund's adjuvant-induced arthritis has been used as an experimental animal model for RA in humans to assess the efficacy of the anti-inflammatory/analgesic drugs. In this study, subcutaneous BV treatment (1mg/kg/day) produced significantly reductions of symptoms related to arthritic pain (i.e. mechanical hyperalgesia and thermal hyperalgesia). The anti-nociceptive effect of BV was observed from at least 12 days after BV treatment. Furthermore, BV treatment significantly suppressed adjuvant induced Fos expression in lumbar spinal cord. We also found that local injection of BV into near the inflammatory site (especially Zusanli-acupoint) showed more potent analgesic effect on arthritic pain rather than distant injection of BV from inflammatory site (arbitrary side of back). The present study demonstrates that BV treatment has anti-nociceptive effect on arthritis induced inflammatory pain. The analgesic effect of BV on RA is probably mediated by the effect of BV itself or possible other mechanism such as counter-irritation. Furthermore, it is possible that BV acupuncture is one of the promising candidates for long-term therapy of RA.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.32 no.2
• /
• pp.181-192
• /
• 2022

The emergence of new malware is incapacitating existing signature-based malware detection techniques., and applying various anti-analysis techniques makes it difficult to analyze. Recent studies related to signature-based malware detection have limitations in that malware creators can easily bypass them. Therefore, in this study, we try to build a machine learning model that can detect and classify the anti-analysis techniques of packers applied to malware, not using the characteristics of the malware itself. In this study, the n-gram opcodes are extracted from the malicious binary to which various anti-analysis techniques of the commercial packers are applied, and the features are extracted by using TF-IDF, and through this, each anti-analysis technique is detected and classified. In this study, real-world malware samples packed using The mida and VMProtect with multiple anti-analysis techniques were trained and tested with 6 machine learning models, and it constructed the optimal model showing 81.25% accuracy for The mida and 95.65% accuracy for VMProtect.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.523-530
• /
• 2005

This paper addresses sliding mode control (SMC) of the anti-lock braking system (ABS) with a compensator of model uncertainties such as vehicle parameter variation, unmodeled dynamics, and external disturbances. A sliding mode controller (SMC) is designed with a nominal vehicle model to achieve a desired wheel slip ratio. A disturbance observer (DOB) is introduced to compensate the model uncertainties and is designed with a transfer function of a hydraulic brake dynamics. Through simulations on the model uncertainties, it is verified that the sliding mode control with the DOB can give the simulation results better than the sliding mode control without the DOB.