• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.78-81
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• 2002

This paper describes on the design structure and development temperature stable strip-line junction isolator operating in above resonance mode. Temperature characteristics of isolator depend on magnet, YIG(Yttium Iron Garnet) ferrite, and conductor etc. These require temperature stability and possible methods of compensation for the temperature dependent effects. In this paper, the analysis and measurement of the temperature characteristics were carried out for the material isolator prototype. The bandwidth of isolator was expended and the center frequency shift was reduced in temperature range of -20∼8O$^{\circ}C$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.12
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• pp.1075-1078
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• 2002

This paper describes on the design structure and development of temperature stable strip-line function isolator operating In above resonance mode. Temperature characteristics of isolator depend on magnet, YIG(Yttium Iron Garnet) ferrite, and conductor etc. These require temperature stability and possible methods of compensation for the temperature dependent effects. In this paper, the analysis and measurement of the temperature characteristics were carried out for the material isolator prototype. The bandwidth of isolator was expended and the frequency shift at center was reduced in the temperature range of -20∼80$\^{C}$.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.169-169
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• 2005

• Journal of Positioning, Navigation, and Timing
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• v.3 no.4
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• pp.143-147
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• 2014

The mean temperature is one of the key parameters in computing Precipitable Water Vapor (PWV) from Global Positioning System (GPS) measurements and is usually derived as a function of surface temperature through the use of a mean temperature equation (MTE). In this study, two new types of MTEs were developed as functions solely of the observation time so that the mean temperature can be obtained without surface temperature measurements. To validate the new models, we created one-year time series of GPS-derived PWV using the new MTEs and compared them with the radiosonde-observed PWV. The bias and root-mean-square error were on the other of ~1 mm and ~2 mm, respectively.

• Journal of Welding and Joining
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• v.20 no.4
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• pp.544-550
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• 2002

Arc-spot welding is generally used in joining of precise parts such as case and core in electronic compressor. It is important to control joining deformation in electronic compressor because clearance control in micrometer order is needed for excellent airtightness and anti-nose. The countermeasures far this deformation in field have mainly been dependent on the rule of try and error by operator's experience because of productivities. For control this deformation problem without influence on productivities, development of exact simulation model should be needed. In this study, to solve this deformation problem in arc-spot welded structure with case and core, we intend to make a simulation model that is able to predict deformation in precise order by tuning and feedback between sensing data and simulation results. This paper include development of heat input model for arc-spot welding, temperature monitoring and make a heat transfer model using sensing data in product.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.165-172
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• 2022

Insects have evolved successfully by adapting to their environments through development and reproduction. Temperature-dependent models have been used to calculate the intrinsic optimal, optimal development, and optimal fecundity temperatures of insects and mites; for this study, we reviewed 112 works that focused on these parameters. The insects and mites investigated in this study include 14 Acari, 8 Coleoptera, 5 Diptera, 31 Hemiptera, 7 Hymenoptera, 18 Lepidoptera, 1 Orthoptera, 5 Psocoptera, and 5 Thysanoptera species. The results of this study showed that the interval distance between the intrinsic optimal and optimal fecundity temperatures was smaller than that between the intrinsic optimal and optimal development temperatures of the all insects and mites investigated except for those in the order Thysanoptera. We found that there is a close relationship between the intrinsic optimal and optimal fecundity temperatures.

• Geomechanics and Engineering
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• v.19 no.2
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• pp.193-199
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• 2019

A frozen fringe plays a key role in frost heave development in soils. Previous studies have focused on the physical and mechanical properties of the frozen fringe, such as overall hydraulic conductivity, water content and pore pressure. It has been proposed that the thickness of the frozen fringe controls frost heave behavior, but this effect has not been thoroughly evaluated. This study used a temperature-controllable cell to investigate the impact of frozen fringe thickness on the characteristics of frost heave. A series of laboratory tests was performed with various temperature boundary conditions and specimen heights, revealing that: (1) the amount and rate of development of frost heave are dependent on the frozen fringe thickness; (2) the thicker the frozen fringe, the thinner the resulting ice lens; and (3) care must be taken when using the frost heave ratio to characterize frost heave and evaluate frost susceptibility because the frost heave ratio is not a normalized factor but a specimen height-dependent factor.

• Structural Engineering and Mechanics
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• v.46 no.1
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• pp.53-73
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• 2013

Prediction of prestressed concrete girder integral abutment bridge (IAB) load effect requires understanding of the inherent uncertainties as it relates to thermal loading, time-dependent effects, bridge material properties and soil properties. In addition, complex inelastic and hysteretic behavior must be considered over an extended, 75-year bridge life. The present study establishes IAB displacement and internal force statistics based on available material property and soil property statistical models and Monte Carlo simulations. Numerical models within the simulation were developed to evaluate the 75-year bridge displacements and internal forces based on 2D numerical models that were calibrated against four field monitored IABs. The considered input uncertainties include both resistance and load variables. Material variables are: (1) concrete elastic modulus; (2) backfill stiffness; and (3) lateral pile soil stiffness. Thermal, time dependent, and soil loading variables are: (1) superstructure temperature fluctuation; (2) superstructure concrete thermal expansion coefficient; (3) superstructure temperature gradient; (4) concrete creep and shrinkage; (5) bridge construction timeline; and (6) backfill pressure on backwall and abutment. IAB displacement and internal force statistics were established for: (1) bridge axial force; (2) bridge bending moment; (3) pile lateral force; (4) pile moment; (5) pile head/abutment displacement; (6) compressive stress at the top fiber at the mid-span of the exterior span; and (7) tensile stress at the bottom fiber at the mid-span of the exterior span. These established IAB displacement and internal force statistics provide a basis for future reliability-based design criteria development.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.556-566
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• 2022

The temperature-dependent development of Poinsettia thrips, Echinothrips americanus was studied at eight constant temperatures (15.0, 17.5, 20.0, 22.5, 25.0, 27.5, 30.0, and 32.5±1℃), 65±5% RH and photoperiod of 16L:8D conditions. The developmental stages were divided into egg, 1st instar, 2nd instar, pre-pupa, pupa, and adult. The total developmental time in the immature stage was 40.4 days at 15.0℃ and 11.6 days at 30.0℃, and it decreased with increasing temperature. The lowest temperature of the whole immature period was 10.7℃, and the cumulative temperature to complete the entire immature period was 217.4 degree days. The optimal development temperature (T_opt) for the whole immature stage was estimated to be in the range of 30.51-31.21℃. T_opt for each immature stage was 31.64-35.47℃ at egg, 30.02-33.08℃ at 1st instar, 29.16-34.43℃ at 2nd instar, 27.63-29.21℃ at pre-pupa, and 29.81-30.12℃ at pupa. In the analysis of the six non-linear models, Logan 6 model was the most appropriate as Zi(Weighting Factors) was 0.18.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.319-323
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• 2008

Mutant rice cv. Goami2 (G2) and Baegjinjoo (BJJ) derived from a high-quality japonica rice cv. Ilpumbyeo (IP) were extruded under different feed moisture (20 and 30%) and barrel temperature (90, 110, and $130^{\circ}C$). Increasing feed moisture at fixed barrel temperature increased extrudate density (ED) in IP and BJJ. Whereas, G2 showed a varied ED depending on extrusion conditions; increasing barrel temperature decreased the ED of G2 extrudate with low feed moisture, but increased with high moisture. Results indicated a positive barrcl temperature effect on volume expansion in IP and G2, but a negative effect on 811, probably due to shrinkage of expanded products containing low-amylose contents. A significant increase of water absorption was found in G2 and BJJ extruded flour, while an increase of water solubility in those from IP. Non-digestible carbohydrates measured by total dietary fiber (TDF) indicated that extrusion increased slightly TDF in IP and BJJ extrudates, but decreased in G2 products, which might be variety-dependent.