• Journal of the Korean Wood Science and Technology
• /
• v.43 no.4
• /
• pp.446-455
• /
• 2015

Based on comparative studies on standards and grading procedures of machine graded lumber in Korea and other countries, this study proposed a procedure of determining the grade classification and design strengths of domestic machine graded lumber. Differences between machine stress rated lumber and E-rated laminations were detailed in order to clarify the need for the procedure improvement. To this improvement the use of average MOE requirement for grading was introduced instead of the fixed minimum MOE requirement which is currently used in the Korean standards. It was found that the fixed minimum MOE requirement method was easier for an inspector to grade but, less efficient as a strength predictor than the average MOE requirement method. The advantage of average MOE requirement method is statistically MOR-MOE regression-based MOR prediction and highly efficient in quality control though it requires a computer-aided operation system in an initial setup. A major weakness of the current Korean grading system was found that different strength characteristics depending on wood species were not reflected on the grade classification and the tabulated allowable design stress. The proposed procedures were developed taking advantages of respective merits of both methods and based on MOR-MOE regression analysis. Through this procedure, the grades of machine stress rated lumber should be revised to become interchangeable with E-rated lamination, which would be beneficial to the cost competitiveness of domestic machine graded lumber and glued laminated timber industry.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.6 no.3
• /
• pp.142-151
• /
• 2001

Detailed interpretation of some high-resolution seismic profiles in Yosu Strait reveals that Late Quaternary deposits consist of three allostratigraphic units (UH, LH, PL) formed by fluvial and tidal controls. The top mud unit, UH, thins onshore, and overlies the backstepping modem Seomjin delta deposits, which is interpreted as a transgressive systems tract (757) related to Holocene relative sea-level rise. The unit LH below the unit UH is composed of delta, valley- and basin-fill facies. The delta facies (Unit $LH_1$) occurs only in Gwangyang Bay and shows two prograding sets retrogradationaly stacked, thus it is also interpreted as a transgressive systems tract(757). On the contrary, the valley- and basin-fill facies (Unit $LH_2$), interpreted as 757, occur between the units UH and PL (Pleistocene deposits) in Yosu Strait. The bounding surface between UH and $LH_2$ can be interpreted as a tidal ravinement surface on the basis of trends thinning toward inner bay and becoming young landward. Furthermore its geomorphological pattern is similar to that of recent tidal channels. This allostratigraphy in'ffsu Strait suggests that two 757 deposits (UH and $LH_2$), divided by tidal ravinement surface, have been formed in Yosu Strait, whereas in Gwangyang Bay backstepping delta deposits ($LH_1$) without tidal ravinement surface have been formed during Holocene sea-level rise. These characteristics indicate that different stacking patterns could be formed in these two areas according to different increasing rate of accommodation space caused by different geomorphology, sediment supply and tidal-current patterns even in the same period of Holocene sea-level rise.

• Journal of Life Science
• /
• v.20 no.1
• /
• pp.55-59
• /
• 2010

In this study, the physicochemical and sensory characteristics of chicken press ham not fed with citrus byproduct (T0) and fed with citrus byproduct (T1) were compared. There was not a significant difference in moisture, crude protein, crude fat, crude ash, crude fiber, Hunter's $L^*$ (lightness), $a^*$ (redness), $b^*$ (yellowness), hardness, springiness, cohesiveness, gumminess, chewiness, shear force, water holding capacity and pH between T0 and T1. There was not a significant difference between T0 and T1 in terms of the chicken ham's VBN (volatile basic nitrogen) content for the first three weeks of storage, but after the fourth week of storage, the VBN content was 15.1 and 13.7 mg% for T0 and T1, respectively, which implies that feeding citrus byproduct significantly reduced the VBN content. There was not a significant difference between T0 and T1 in terms of the chicken press ham's TBARS (2-thiobarbituric acid reactive substances) value for the first two weeks of storage. However, the TBARS value was 0.31 and 0.22 mg malonaldehyde/kg for T0 and T1 during the third week of storage, and 0.49 and 0.32 mg malonaldehyde/kg for T0 and T1 during the fourth week of storage. There was not a significant difference between T0 and T1 in terms of the chicken press ham's TPC (total plate counts) for the first three weeks of storage, but after the fourth week of storage, the TPC was 4.96 and 4.72 log CFU/g for T0 and T1, respectively, which implies that T1 showed a significantly lower TPC than T0. T1 showed significantly higher aroma, taste, and palatability of the chicken press ham than T0, but there was a not significant difference in texture and juiciness between T0 and T1.

• Journal of Life Science
• /
• v.27 no.2
• /
• pp.123-130
• /
• 2017

This study was conducted to investigate the physicochemical quality characteristics of pork patty added with four different amount (T0:0%, T1:0.3%, T2:0.7%, T3:1.0%) of tangerine (Citrus unshiu) peel. There was no significant difference in chemical composition, cooking yield, water holding capacity, moisture retention, fat retention, hardness, springiness, cohesiveness, gumminess, chewiness, VBN content, L-value. In taste, texture, juiciness and palatability, the addition of 0.3%~1.0% tangerine peel in pork patty showed no significant difference on sensory properties compared to the pork patty without tangerine peel. Total polyphenol content was highest in T3, and DPPH radical scavenging activity was highest in T2 and T3 (p<0.001). The TBARS contents decreased as tangerine peel become added (p<0.001). The pH was highest in T0, and was lowest in T3 (p<0.001). The external a-value of T2 and T3 were significantly higher than that of T0 (p<0.01). The external and internal b-value of T2 and T3 were higher than those of T0 (p<0.01). Flavor of T2 and T3 were higher than those of T0 and T1 (p<0.01). In conclusion, the results of this study indicate that an addition of tangerine peel could be utilized as an ingredient in pork patty in promotion of function of tangerine by-products.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.25 no.2
• /
• pp.109-123
• /
• 2009

The aim of the study was to assess the influence of insertion torque of bone quality and to compare axial force, moment and von Mises stress using finite element analysis of plastoelastic property for bone stress and strain by dividing bone quality to its thickness of cortical bone, density of trabecular bone and existence of lower cortical bone when implant inserted to mandibular premolar region. The $Br{\aa}nemark$ MKIII. RP implant and cylindrical bone finite model were designed as cortical bone at upper border and trabecular bone below the cortical bone. 7 models were made according to thickness of cortical bone, density of trabecular bone and bicortical anchorage and von Mises stress, axial force and moment were compared by running time. Dividing the insertion time, it seemed 300msec that inferior border of implant flange impinged the upper border of bone, 550msec that implant flange placed in middle of upper border and 800msec that superior border of implant flange was at the same level as bone surface. The maximum axial force peak was at about 500msec, and maximum moment peak was at about 800msec. The correlation of von Mises stress distribution was seen at both peak level. The following findings were appeared by the study which compared the axial force by its each area. The axial force was measured highest when $Br{\aa}nemark$ MKIII implant flange inserts the cortical bone. And maximal moment was measured highest after axial force suddenly decreased when the flange impinged at upper border and the concentration of von Mises stress distribution was at the same site. When implant was placed, the axial force and moment was measured high as the cortical bone got thicker and the force concentrated at the cortical bone site. The influence of density in trabecular bone to axial force was less when cortical bone was 1.5 mm thick but it might be more affected when the thickness was 0.5 mm. The total axial force with bicortical anchorage, was similar when upper border thickness was the same. But at the lower border the axial force of bicortical model was higher than that of monocortical model. Within the limitation of this FEA study, the insertion torque was most affected by the thickness of cortical bone when it was placed the $Br{\aa}nemark$ MKIII implant in premolar region of mandible.

• Tuberculosis and Respiratory Diseases
• /
• v.54 no.4
• /
• pp.439-448
• /
• 2003

Background : Surfactant protein B(SP-B) and surfactant protein C(SP-C) are important in accelerating surface spreading of surfactant phospholipid. The glucocorticoids accelerate the morphologic differentiation of epithelial cells into type II cells and increase the rate of phosphatidylcholine synthesis. The hydrophobic surfactant protein has been shown to be upregulated by glucocorticoids in vitro, however, its regulation in vivo is not well established. Methods : The authors investigated the effects of glucocorticoid on the accumulation of mRNA encoding SP-B and SP-C protein content of the lung. Adult rats were given different doses of subcutaneous dexamethasone and sacrificed at 24 hours and 1 week. SP-B and SP-C mRNA were measured by a filter hybridization method. Results : 1) The accumulation of SP-B mRNA at 24 hours after 0.2 mg/kg dexamethasone treatment was increased by 23.7%. 2) The accumulation of SP-B mRNA at 1 week after 2 mg/kg dexamethasone treatment was significantly increased by 96.6%(P<0.001). 3) The accumulation of SP-C mRNA at 24 hours after 0.2 mg/kg dexamethasone treatment was significantly increased by 42.7%(P<0.01). 4) The accumulation of SP-C mRNA at 1 week after 2 mg/kg dexamethasone treatment was significantly increased by 60.0% (P<0.01). Conclusion : The authors concluded that dexamethasone treatment in vivo resulted in increased levels of SP-B mRNA and SP-C mRNA. These results suggested that dexamethasone stimulates the synthesis of hydrophobic proteins associated with surfactant.

• Geophysics and Geophysical Exploration
• /
• v.12 no.1
• /
• pp.121-131
• /
• 2009

In recent years, microtremor array observations have been used for estimation of shear-wave velocity structures. One of the methods is the conventional spatial autocorrelation (SPAC) method, which requires simultaneous recording at least with three or four sensors. Modified SPAC methods such as 2sSPAC, and linear array methods, allow estimating shear-wave structures by using only two sensors, but suffer from instability of the spatial autocorrelation coefficient for frequency ranges higher than 1.0 Hz. Based on microtremor measurements from four different size triangular arrays and four same-size triangular and linear arrays, we have demonstrated the stability of SPAC coefficient for the frequency range from 2 to 4 or 5 Hz. The phase velocities, obtained by fitting the SPAC coefficients to the Bessel function, are also consistent up to the frequency 5 Hz. All data were processed by the SPAC method, with the exception of the spatial averaging for the linear array cases. The arrays were deployed sequentially at different times, near a site having existing Parallel Seismic (PS) borehole logging data. We also used the imaginary part of the SPAC coefficients as a data-quality indicator. Based on perturbations of the autocorrelation spectrum (and in some cases on visual examination of the record waveforms) we divided data into so-called 'reliable' and 'unreliable' categories. We then calculated the imaginary part of the SPAC spectrum for 'reliable', 'unreliable', and complete (i.e. 'reliable' and 'unreliable' datasets combined) datasets for each array, and compared the results. In the case of insufficient azimuthal distribution of the stations (the linear array) the imaginary curve shows some instability and can therefore be regarded as an indicator of insufficient spatial averaging. However, in the case of low coherency of the wavefield the imaginary curve does not show any significant instability.

• Food Science and Preservation
• /
• v.8 no.4
• /
• pp.427-433
• /
• 2001

The purpose of this study was to investigate the effect of chitosan on the shelf-life and quality of Paeksulkis(Korea rice cake). Paeksulgis containing 0-0.5% chitosan were stored at 5$^{\circ}C$ for 4 week and 2$0^{\circ}C$ for 1 week to test the effect of extenting shelf-life of Paeksulgis by chitosan. The pH of Paeksulkis was 5.65 without chitosan and pH of those were about 7.0(6.94-7.01) with 0.05-0.5% level of chitosan. Moisture content of Paekrukis wish or without chitosan was 38-40%. In Hunter’s color values of Paeksulkis of control, the lightness (L) was 84.28, redness(a) was -1.56 and yellowness(b) was 7.68. The lightness (L), redness(a) and yellowness(b) of Paeksulkis were increased by the increasing concentration of chitosan. In mechanical characteristics, cohesiveness concentration of Paeksulkis were the highest in control while obtained the highest score in color, after swallowing and overall quality (p<0.05). The score of flavor and consistency of Paeksulkis with different levels of chitosan wre not significant while the score of moisture in Paeksulkis with 0.05-0.5% level of chitosan was significantly higher than control (p<0.05). The score of flavor and consistency of Paeksulkis with different levels of chitosan were not significant while the score of moisture in Paeksulkis with 0.05-0.5% level of chitosan was significantly higher than control (p<0.05). Total bacterial counts (TBC) of Paeksulgis immediately before storage were 4.2$\times$10$^2$CFU/g in control and those containing 0.3-0.5% of chitosan were 0.5-1.0 log cycle lower than control. TBC of Paelsulgis containing chitosan was lower than increased for 2 weeks, reached at 1.8$\times$10$^{5}$ CFU/g and decreased for 2 weeks, reached at 1.8$\times$10$^4$CFU/g during storage at 5$^{\circ}C$. TBC of Paeksulkis with more than 0.3% of chitosan were 1.9 log cycles lower than that of control during storage at 5$^{\circ}C$. TBC of Paeksulkis with more than 0.3% of chitosan were 1.9 log cycles lower than that of control during storage at 5$^{\circ}C$ for 4 weeks. TBC of Paeksulgis increased to 10$^{8}$ CFU/g in control and 10$^{6}$-10$^{7}$ CFU/g in more than 0.3% chitosan during storage at 20$^{\circ}C$ for 1 week. The shelf-life of Paeksulkis was increased with increasing concentration of chitosan both temperature at 5$^{\circ}C$ and 20$^{\circ}C$.

• Food Science and Preservation
• /
• v.18 no.5
• /
• pp.692-699
• /
• 2011

This study was conducted to investigate the physicochemical characteristics of yanggaeng prepared with pear juice and dried pear powder. The proximate composition and total polyphenol content, antioxidant activities, Hunter's color values, texture, sensory properties of pear yanggaeng variants [pear juice (PJ), pear juice and hot-air-dried pear powder (PJH), pear juice and freeze-dried pear powder (PJF) yanggaeng] were examined. The moisture content was highest (27.9%) in the control (C) yanggaeng, but the latter's energy and carbohydrate content were lower than in the pear yanggaeng variants. The differences between the pear yanggaeng variants were not significant.The total polyphenol content was highest in the 20.7 mg/100g PJF yanggaeng. The antioxidant activities of PJF yanggaeng were higher than those of the other pear yanggaeng varients. The Hunter color value results showed that the lightness (L) values were highest in C yanggaeng whereas the redness(a) and yellowness(b) values were highest in PJH yanggaeng. The springiness in texture was lowest in C yanggaeng and not significant in the others. The hardness and chewiness were highest in PJH and PJF yanggaeng, but adhesiveness was lowest therein. The results of the sensory test showed that PJF yanggaeng was the highest in flavor, color, taste, hardness, chewiness, and overal quality. Based on these results, it can be concluded that pear juice and freeze-dried pear powder yanggaeng has excellent physicochemical and antioxidant activities.

• Journal of the East Asian Society of Dietary Life
• /
• v.21 no.3
• /
• pp.345-352
• /
• 2011

TMR feed was developed by adding mugwort (Artemisia capillaris), and was fed to Hanwoo cattle to investigate the effects of feeding mugwort on the physicochemical and sensory characteristics of rump meat, and to determine the feasibility of producing Hanwoo beef with high quality and functionality. The experimental samples consisted of the Hanwoo rump from cattle fed with fattening TMR feed without mugwort (T0), and those fed with fattening cattle TMR feed supplemented with mugwort (T1). T1 was significantly higher than T0 for Hanwoo rump characteristics of Hunter's $L^*$, $a^*$, $b^*$ values (p<0.05). VBN content for T0 was significantly higher than for T1, and EDA for T1 was significantly higher than for T0 (p<0.05). There was no significant difference between T0 and T1 in terms of pH, TBARS, and total bacterial numbers. Water holding capacity for T1 was significantly higher than for T0 (p<0.05), but there was no significant difference between T0 and T1 in terms of freezing loss, thawing loss, and cooking loss. Springiness for T1 was significantly higher than for T0 (p<0.05), and there was no significant difference between T0 and T1 in terms of hardness, cohesiveness, gumminess, chewiness, and shear force. There was no significant difference between T0 and T1 in terms of acid value, peroxide value, and iodine value. However, the melting point for T1 was significantly lower than for T0 (p<0.05). Aroma of raw meat for T1 was significantly superior to aroma for T0 (p<0.05). Taste, palatability of boiled meat, and juiciness of roasted meat for T1 were significantly superior to those parameters for T0 (p<0.05). These results suggest that the feed containing mugwort can be used to improve color and sensory characteristics, inhibit VBN formation, and also to increase antioxidant ability as a functional feed.