• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.46 no.6
• /
• pp.41-49
• /
• 2014

The research was performed to investigate the weathering characteristics of fruit growth paper bags. The bags were used to cover fruits such as grapes and pears. And then they were collected after 30 and 60 days exposure at the orchard. The physical and optical properties of the bags tended to decrease with the exposure times. The larger change on the properties were found on the papers exposed for 30 days. The cover paper for pear showed the largest density changes. The air permeability were decreased with the exposure time in all bags. The cover paper for pear showed the very low values of air permeability. The mechanical properties of the fruit bags showed to be gradually decreased with the length of exposure time. The tear index showed the largest differences. The cover paper for pear showed the rapid decrease on the mechanical properties after 60 days of the exposure. The inner paper, however, showed the strength enough to cover the fruits. The precipitation showed more effect on the degradation of fruit growth paper bags than the light hours.

• Journal of Community Nutrition
• /
• v.6 no.3
• /
• pp.141-145
• /
• 2004

The purpose of this study was to explore the relationship between life style and metabolic syndrome. The cross-sectional survey was conducted in Pingliang community in Shanghai in Jan 2003. The data was collected by questionnaire, and the results were analyzed by SPSS. It was found that the prevalence of Metabolic Syndrome (MS) was $13.4\%$ in the community, and the body mass index (BMI), waist-to-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), serum triglyceride (TG), total cholesterol(TC), low density lipoprotein-cholesterol (LDL-C), and fast plasma glucose (FPG) in MS group were higher than that in non-MS group. Logistic regression analysis indicated that BMI and WHR were positively correlated to the prevalence of MS, and physical activity was negatively correlated to the prevalence of MS. People with higher education levels (${\geq}10y$) had lower BMI, SBP, DBP, LDL-C and FPG. The prevalence of MS in the higher education level group was significantly lower than that of the lower education level group. These results suggested that BMI, WHR and physical activity were important factors of MS, and education background played an important role in the occurrence of MS. Therefore, it is very important to build a healthy life style for preventing and controlling the incidence and developing of MS.

• Journal of the Korean Geotechnical Society
• /
• v.33 no.12
• /
• pp.127-139
• /
• 2017

Site investigation including boring and various in-situ borehole test (Pressuremeter test, Borehole shear test, Downhole test, Suspension PS logging, Density logging) and X-ray fluorescence analysis for rock core sample were performed to estimate geotechnical properties and weathering degree of weathered granite rock in Goyang. Deformation modulus, shear strength parameter and shear wave velocity estimated through in-situ borehole test had a tendency to increase with depth. And several chemical weathering indices evaluated by X-ray fluorescence analysis had a general tendency of reducing weathering degree in accordance with depth. Also, relationship between VR determined as a representative weathering index and the geotechnical properties was analyzed.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2018.05a
• /
• pp.140-141
• /
• 2018

There are three types of high fluidity concrete: powder based, VMA based, and combined. In the case of the powder based high fluidity concrete mixture, according to the textbook, increased viscosity due to the replaced fly ash can prevent segregation of coarse aggregate. On the other hand, decreased density of the powder due to the fly ash replacement can causes segregation but there is no report on this issue. Therefore, in this research, the segregation resistance and segregation evaluation method for powder based high fluid concrete mixture are evaluated. As a result, with increased replacing ration of supplementary materials, EIS value was decreased and apparently segregation resistance was increased. However, from the compressive strength evaluation depending on height of the cylindrical specimen, it was confirmed that the different of strength difference between top and bottom part of the specimen. Thus, following research regarding vertical segregation should be studied.

• Journal of The Korean Astronomical Society
• /
• v.34 no.4
• /
• pp.333-335
• /
• 2001

We study the properties of supernova (SN) driven interstellar turbulence with a numerical magnetohydrodynamic (MHD) model. Calculations were done using the RIEMANN framework for MHD, which is highly suited for astrophysical flows because it tracks shocks using a Riemann solver and ensures pressure positivity and a divergence-free magnetic field. We start our simulations with a uniform density threaded by a uniform magnetic field. A simplified radiative cooling curve and a constant heating rate are also included. In this radiatively-cooling magnetized medium, we explode SNe one at a time at randomly chosen positions with SN explosion rates equal to and 12 times higher than the Galactic value. The evolution of the system is basically determined by the input energy of SN explosions and the output energy of radiative cooling. We follow the simulations to the point where the total energy of the system, as well as thermal, kinetic, and magnetic energy individually, has reached a quasi-stationary value. From the numerical experiments, we find that: i) both thermal and dynamical processes are important in determining the phases of the interstellar medium, and ii) the power index n of the $B-p^n$ relation is consistent with observed values.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1985.01a
• /
• pp.21-23
• /
• 1985

By adding La$_2$O$_3$ to optical multicomponent glass composition, after making mother glass and core fiber that enable to enlarge the infrared transmittance region, then surveyed the optical properties. Through thermal analysis of the glass abstained by melt-quenching after selecting stable basic composition on devitrification and replace SiO$_2$ by 4-12wt% La$_2$O$_3$. As La$_2$O$_3$ increases up to l2wt% transition temperature, refractive index, density, deformation temperature increased, whereas thermal expansion coefficient decreased. As a result of inspectig transmittance in UV/VIS/IR region, visable region indicated the decrease of transmittance by increasing the La$_2$O$_3$ and transmittance region was enlarged by increasing the La$_2$O$_3$ in IR region. Also, fabricate core fiber at 820$^{\circ}C$ and severy the optical loss we could fact that La$_2$O$_3$ composition added 12wt% showed the minimum optical loss.

• Korean Journal of Materials Research
• /
• v.28 no.7
• /
• pp.428-434
• /
• 2018

Hydrogen evolution on a steel surface and subsequent hydrogen diffusion into the steel matrix are evaluated using an electrochemical permeation test with no applied cathodic current on the hydrogen charging side. In particular, cyclic operation in the permeation test is also conducted to clarify the corrosion-induced hydrogen evolution behavior. In contrast to the conventional perception that the cathodic reduction reaction on the steel in neutral aqueous environments is an oxygen reduction reaction, this study demonstrates that atomic hydrogen may be generated on the steel surface by the corrosion reaction, even in a neutral environment. Although a much lower permeation current density and significant slower diffusion kinetics of hydrogen are observed compared to the results measured in acidic environments, they contribute to the increase in the embrittlement index. This study suggests that the research on hydrogen embrittlement in ultra-strong steels should be approached from the viewpoint of corrosion reactions on the steel surface and subsequent hydrogen evolution/diffusion behavior.

• Polymer(Korea)
• /
• v.25 no.4
• /
• pp.528-535
• /
• 2001

Polyurethane specimens were mainly composed of polyol, MDI, silicone surfactant, and water. The effects of ethylene glycol on the cell size, forming magnification, cream time, gel time, take free time, final free rising height, and reactive temperature were investigated. The cyclopentane was used for PU foam as a physical blowing agent. The components were hand-mixed at about 5000 rpm within 4 seconds at room temperature. The mixtures with various ethylene glycol contents were foamed in the wood mold. When the index of isocyanate was fixed, as the amount of ethylene glycol increased, cell size and thermal conductivity were decreased by about 5.1% and 14%, respectively.

• Korean Journal of Optics and Photonics
• /
• v.8 no.1
• /
• pp.37-41
• /
• 1997

The optical property, the environmental stability and the crystallization of ZnS thin films prepared by ion-assisted deposition (IAD) were investigated and compared with those of conventional electron-beam deposited thin films. The humidity(R.H. 85%) test and the thermal(15$0^{\circ}C$) show that the IAD films have relatively higher refractive index, smaller extinction coefficient and environmentally more stable than the conventional films. It is believed to originate from the reduced adsorption of moisture which reflect the increased packing density and the improved microstructure by ion bombardment. XRD experiments also confirm that conventionally grown films have an amorphous in comparison with the crystalline structured IAD films.

• The Research Journal of the Costume Culture
• /
• v.22 no.2
• /
• pp.339-345
• /
• 2014

This study analyzes and compares Hanji made with loess to Hanji made with kaolin, two yellow-based inorganic pigments, in terms of its physical properties, optical properties, and color fastness to light with the aim of using it as a fashion material. Hanji made by adding inorganic pigments showed an approximately 20% retention ratio on average. This figure was similar to those of loess and kaolin. Physical properties were analyzed, with the following results. A higher amount of additives lowered the apparent density and increased thickness and bulk. In general, inorganic pigment-added Hanji had lower tensile strength, bursting strength, and folding endurance compared to non-additive Hanji. The analysis of optical properties showed a lower brightness index for Hanji made with inorganic pigments compared to non-additive Hanji. When comparing the two inorganic pigments, the brightness of Hanji made with kaolin was higher. Regarding color fastness to light, loess showed level 4 and kaolin showed level 5 when 25% inorganic pigments on pulp were added to Hanji. Thus, Hanji made by adding inorganic pigments during the manufacturing process may perform well as materials for fashion because the additives enhanced both the color fastness to light and the bulk while maintaining the strength. In addition, Hanji dyed with inorganic pigments may have the potential to serve as materials for the fashion industry while still retaining the characteristics of Hanji.