• Journal of Biomedical Engineering Research
• /
• v.36 no.5
• /
• pp.162-168
• /
• 2015

In this study, we suggested the performance and safety testing guideline for low intensity pulsed ultrasound (LIPUS) represented by the ultrasound fracture treatment device and cartilage treatment device and low intensity focused ultrasound (LIFU) represented by ultrasonic face lifting device. For these study, the international standards and management regulations of Korea, Japan and United State were analyzed. And the usefulness and applicability were evaluated by testing with commercial equipment and reflecting the views of the industry and experts. As a result of this study, the safety and performance test guidelines for low intensity therapeutic ultrasound device were proposed by presenting the 10 items for LIPUS and 12 items for LIFU. The suggested guidelines are considered a high utilization in the domestic testing and approval authorities. And they are also thought to be useful to new technology development.

• Journal of the Korean Society of Industry Convergence
• /
• v.25 no.2_1
• /
• pp.141-148
• /
• 2022

In this paper, the evaluation equations proposed by Tange et al. and Ando et al. were used to evaluate the threshold stress intensity factor ∆K^R_th(s) and fatigue limit ∆𝜎^R_wc, according to the small crack of offshore structural steel F690. Despite the differences in concept and shape of the two equations, the ∆K^R_th(s) and ∆𝜎^R_wc proved completely consistent. It is possible to use these equations to evaluate the dependence of the crack length on the ∆K^R_th(s) and ∆𝜎^R_wc of structures made of all steel grades. With these equations, the characteristics of microcracks can be quantitatively evaluated, and the safety and reliability of the structure can be secured.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.47 no.2
• /
• pp.103-113
• /
• 2014

This study compared the food quality of freshwater rainbow trout Oncorhynchus mykiss cultured (in Pyeongchang, Pyeongtaek, Jecheon and Geochang) with that of imported salmon Oncorhynchus keta. The proximate composition of the four types of rainbow trout was 74.4-75.7% moisture, 18.3-19.4% crude protein, 3.1-4.3% crude lipid, and 1.3-1.7% ash. There were slight differences in the proximate composition of the four types of rainbow trout. No significant (P>0.05) differences were found in the red color and odor and taste intensities of the four types of rainbow trout based on the Hunter a values, volatile basic nitrogen content, odor intensity using an electronic nose and taste intensity using an electronic tongue. The crude protein, total amino acid, and mineral contents of rainbow trout cultured in Pyeongtaek were superior or similar to those of the trout cultured in the other three places. The rainbow trout cultured in Geochang had the highest hardness, at 858.5 g.

• Journal of Korea Technology Innovation Society
• /
• v.8 no.1
• /
• pp.116-134
• /
• 2005

This paper investigates the relationships between export and firm characteristics, focusing on technology factors. It is based on a longitudinal data covering listed firms in the Korean manufacturing industry. A regression model for the determinant of export/sales ratio including dynamic adjustment process is tested on a cross-section sample of the year 2001. Empirical findings suggest that there is no significant relationship between export/sales ratio and firm's technological level. The hypotheses concerning human capital intensity and physical capital intensity are also rejected. But we found a positive and inversely U-shaped relationship between firm size and export/sales for basic material and capital good industry. As a dynamic aspect, we found that the pattern of export/sales ratio changed unstably over the last decade. Finally, some policy implications are presented.

• Journal of the Korean Society of Industry Convergence
• /
• v.6 no.4
• /
• pp.367-371
• /
• 2003

In order to determine the effective way of measuring the Mode I stress intensity factor for a material containing a two-dimensional surface crack by means of the alternating current potential drop(ACPD) technique, the change in magnetic flux density between crack surfaces and above the specimen surface due to load was studied theoretically. The magnetic flux density in the air between crack surfaces is uniform and above the specimen surface is not changed by increasing the load in the material. Therefore, the change in potential drop due to load in a measuring system which was designed to induce a large amount of electro-motive force was caused by the change in internal inductance of material, the change in the mutual inductance between internal inductance of material and measuring system and the change in the mutual inductance between internal inductance of material and power supply line.

• Journal of Technology Innovation
• /
• v.16 no.2
• /
• pp.1-16
• /
• 2008

This paper shows that labor mobility is positively related to R&D intensity at the industry level in Korea. Different from the perception based on individual firm-level studies arguing that firms can be reluctant to R&D in fear of the job transfer of employees, firms in industries which have high job transfer of employees turn out not to reduce investment in R&D. This result is also confirmed by 2SLS regression. This result supports that, if there exist spillover effects through the job transfer of employees, job transfer can positively contribute to R&D activities.

• Journal of the Korean Society of Industry Convergence
• /
• v.7 no.1
• /
• pp.129-132
• /
• 2004

In order to determine the effective way of measuring the Mode I stress intensity factor, $K_I$, by means of the alternating current potential drop(ACPD) technique for a material containing a two-dimensional surface crack, the change in magnetic flux density above the cracked specimen surface was studied experimentally. The change in magnetic flux in the air above the cracked specimen made of aluminum alloy is measured by changing the load by four-point bending. The magnetic flux in the air is almost not changed by increasing the load in teh specimen. The change in potential drop due to load is not caused by the change in electro-motive force induced in the coiled measuring system. This experimental result agree to the result of theoretical analysis in reference 7).

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.32 no.5
• /
• pp.8-13
• /
• 2000

X-ray diffraction technique was used to quantify change of cellulose crystallinity during refining. XRD data confirmed that fiber wall delamination was caused by the structural conversion of celluloses which occurred in a liquid medium during refining. The quantified crystallinity of celluloses in pulp fibers was closely associated with the change of fiber wall delamination, which was defined by measurement of fiber wall thickness. In particular, it was well recognized that low intensity beating showed a better response in the change of crystallinity than high intensity one. The decrease o cellulose crystallinity during refining considerably enhanced the improvement of interfiber bonding ability of a dried sheet.

• Korean Business Review
• /
• v.9
• /
• pp.286-309
• /
• 1996

• Bulletin of Food Technology
• /
• v.22 no.4
• /
• pp.693-699
• /
• 2009