• 열처리공학회지
• /
• 제2권2호
• /
• pp.38-45
• /
• 1989

The Cu-Fe permanent magnet were prepared in situ process, which has economic and mass productive merits in producing multi filamentary composites. The purpose of this research was to study the effect of reduction ratio and heat treatment on magnetic property. As the reduction ratio of Cu-Fe wire increased, the filament structure became finer and interfilament distances decreased and the morphology of filament cross section became ribbon shape. As Fe content increased significantly. The coercivity and squareness of Cu-55 wt%Fe composite increased as a reduction ratio became higher, whereas they increased to maximum values at 0.09 mm ${\phi}$ for Cu-30 wt%Fe, and 0.066 mm ${\phi}$ for CU-45 wt%Fe respectively, and decreased for further reduction. The magnetic properties of Cu-Fe composites can be more enhanced by intermediate heat treatment. The best magnetic properties were obtained from Cu-55 wt%Fe composite deformed to 0.054 mm ${\phi}$ and annealed.

• 한방재활의학과학회지
• /
• 제19권2호
• /
• pp.275-287
• /
• 2009

Objectives : In order to observe clinical effects, carboxytherapy and electroacupuncture, we analyzed relation effect and patients' character, and researched correlation among reduction of BFM(Body Fat Mass), WHR(Waist-Hip Ratio) and AC(Arm Circumference). Methods : Among outpatients who had admitted to department of oriental rehabilitation medicine, Dae-Jeon oriental medicine hospital, Dae-Jeon university from January to September, 2008 for obesity treatment and abdominal fat, 44 subjects were chosen and carboxytherapy and electroacupuncture were practiced concurrently. Results : 1. The group under the concurrent practice of carboxytherapy and electroacupuncture showed significant decrease in BFM, BFR(Body Fat Rate), WHR and AC. 2. The group under the concurrent practice of carboxytherapy and electroacupuncture did not show statistical significance but showed decrease in BFM, WHR. The degree of decrease was proportional to that of obesity. 3. As AC decreased, BFM, WHR reduction tended to increase as well in the group under the concurrent practice of carboxytherapy and electroacupuncture. 4. Compared to the group under the sole practice of electroacupuncture, the group under the concurrent practice of carboxytherapy and electroacupuncture showed less change in BFM reduction and greater change in WHR reduction. Conclusions : From the above results, the concurrent practice of carboxytherapy and electroacupuncture had an effect on obesity and reducing abdominal fat, but did not show statistically significant decrease compare to the sole practice of electroacupuncture.

• 한국물환경학회지
• /
• 제31권4호
• /
• pp.407-417
• /
• 2015

Soil loss is one of the significant disasters which have threatened human community and ecosystem. Particularly, Korea has high vulnerability of soil loss because rainfall is concentrated during summer and mountainous regions take more than 70% of total land resources. Accordingly, the sediment control management plan are required to prevent the loss of soil resources and to improve water quality in the receiving waterbodies. In this regard, the objectives of this study are 1) to quantify the effect of the Vegetative Filter Strip (VFS) on sediment runoff reduction and 2) to analyze the relationship of rainfall intensity and sediment runoff. For this, SATEEC and VFSMOD were used to estimate sediment runoff according to rainfall intensity and to quantify the effect of VFS on sediment runoff reduction, respectively. In this study, the VFS has higher impact on sediment reduction for lower maximum rainfall intensity, which means that the maximum rainfall intensity is one of significant factors to control sediment runoff. Also, the sediment with VFS considered was highly correlated with maximum rainfall intensity. For these results, this study will contribute to extend the applicability of VFS in establishing eco-friendly sediment control plans.

• 재활간호학회지
• /
• 제6권2호
• /
• pp.248-256
• /
• 2003

Purpose: This research was for checking the effect of meridian massage on the reduction of pain and subjective symptoms of myofascial pain syndrome. Method: The method of the research was interruptive time series design. The research objects are 25 hospital workers with myofascial pain syndrome at B hospital in Busan from July 22, 2002 to August 18, 2002. SPSS Win 10.0 was used for data analysis, paired t-test and repeated measures ANOVA for hypothesis test. Result: The recipients of meridian massage felt less pain than before(F=12.587, p=.000). The recipients of meridian massage felt less often than before (F=6.705, p=.001). The recipients of meridian massage got lower score on subjective symptoms of myofascial pain than before(F=12.857, p=.000). The recipients of meridian massage had lower blood pressure than before(systolic blood pressure; t=4.697, p=.000, diastolic blood pressure; t=3.426, p=.002). The recipients of meridian massage did not get the lower number of pulse than before(t=0.33, p=.744). Conclusion: The above results show that meridian massage is effective on the reduction of pain and subjective symptoms of myofascial pain syndrome and makes stable the blood pressure. Therefore meridian massage can be apply as the effective intervention for the reduction of pain and subjective symptoms of myofascial pain syndrome.

• Structural Engineering and Mechanics
• /
• 제24권3호
• /
• pp.275-290
• /
• 2006

In this paper, the performance of a tuned liquid damper (TLD) in suppressing the seismic response of buildings is investigated with shake table testing of a four-story steel frame model that rests on pile foundation. The model tests were performed in three phases with the steel frame structure alone, the soil and pile foundation system, and the soil-foundation-structure system, respectively. The test results from different phases were compared to study the effect of soil-structure interaction on the efficiency of a TLD in reducing the peak response of the structure. The influence of a TLD on the dynamic response of the pile foundation was investigated as well. Three types of earthquake excitations were considered with different frequency characteristics. Test results indicated that TLD can suppress the peak response of the structure up to 20% regardless of the presence of soils. TLD is also effective in reducing the dynamic responses of pile foundation.

• Geomechanics and Engineering
• /
• 제12권2호
• /
• pp.257-267
• /
• 2017

This paper presents laboratory investigation of stabilization of subgrade soil. One type of soil and three types of stabilizers i.e., hydrated lime, class F fly ash and polypropylene fibres are selected in the study. Atterberg limit, compaction, california bearing ratio (CBR), unconfined compressive strength and triaxial shear strength tests are conducted on unstabilized and stabilized soil for varying percentage of stabilizers to analyze the effect of stabilizers on the properties of soil. Vertical compressive strains at the top of unstabilized and stabilized subgrade soil were found out by elasto-plastic finite element analysis using commercial software ANSYS. Strategy for design of optimum pavement section was based on extension in service life (TBR) and reduction in layer thickness (LTR). Extension in service life of stabilized subgrade soil is 6.49, 4.37 and 3.26 times more due to lime, fly ash and fibre stabilization respectively. For a given service life of the pavement, there is considerable reduction in layer thicknesses due to stabilization. It helps in reduction in construction cost of pavement and saving in natural resources as well.

• 한국지진공학회논문집
• /
• 제17권4호
• /
• pp.159-169
• /
• 2013

The purpose of this study is to investigate the inelastic behavior of hollow reinforced concrete bridge column sections with reinforcement details for material quantity reduction and to provide the details and reference data. Among the numerous parameters, this study concentrates on the shape of the section, the reinforcement details, the diameter of the transverse reinforcement and loading types. Eighteen column section specimens were tested under quasi-static monotonic loading. In this study, the computer program RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) was used. A modified lateral confining effect model was adopted for the hollow bridge column sections. This study documents the testing of hollow reinforced concrete bridge column sections with reinforcement details for material quantity reduction and presents conclusions based on the experimental and analytical findings.

• 전기화학회지
• /
• 제16권3호
• /
• pp.138-144
• /
• 2013

Electrochemical reductions of $UO_2$ at various anode-to-cathode distances (1.3, 2.3, 3.2, 3.7 and 5.8 cm) were carried out to investigate the effect of the anode-to-cathode distance on the electrochemical reduction rate. The geometry of the electrolysis cell in this study, apart from the anode-to-cathode distance, was identical for all of the electrolysis runs. Porous $UO_2$ pellets were electrolyzed by controlling a constant cell voltage in molten $Li_2O-LiCl$ at $650^{\circ}C$. A steel basket containing the porous $UO_2$ pellets and a platinum plate were used as the cathode and anode, respectively. The metallic products were characterized by means of a thermogravimetric analyzer, an X-ray diffractometer and a scanning electron microscope. The electrolysis runs conducted during this study revealed that a short anode-to-cathode distance is advantageous to achieve a high current density and accelerate the electrochemical reduction process.

• 산업공학
• /
• 제19권4호
• /
• pp.316-323
• /
• 2006

In this study, based on Weibull proportional age reduction model and age replacement policy, we analyze economic life of cutting tool which allows re-grinding. Re-grinding task, usually for high-priced machining tools(e.g., broaching tool), is a kind of preventive maintenance activities to extend tool life at the completion of a lot production. The numerical results are also presented. Among the parameters of Weibull proportional age reduction model, the re-grinding effect parameter and Weibull shape parameter have a strong effect on economic tool life, and in the cost parameters, shortage cost is most sensitive. With further study on the parameter estimation of tool life process and cost function, this study can be expected to give more practical contribution to management of general machining tools.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제19권1호
• /
• pp.63-69
• /
• 2014

This paper presents the feasibility of using different iron oxides (microscale hematite (HT), microscale magnetite (MT), and nanoscale maghemite (NMH)) in enhancing nitrate reduction by zero-valent iron (Fe(0)) under two solution conditions (artificial acidic water and real groundwater). Addition of MT and NMH into Fe(0) system resulted in enhancement of nitrate reduction compared to Fe(0) along reaction, especially in groundwater condition, while HT had little effect on nitrate reduction in both solutions. Field emission scanning electron microscopy (FESEM) analysis showed association of MT and NMH with Fe(0) surface, presumably due to magnetic attraction. The rate enhancement effect of the minerals is presumed to arise from its role as an electron mediator that facilitated electron transport from Fe(0) to nitrate. The greater enhancement of MT and NMH in groundwater was attributed to surface charge neutralization by calcium and magnesium ions in groundwater, which in turn facilitated adsorption of nitrate on Fe(0) surface.