• Korean Journal of Poultry Science
• /
• v.38 no.1
• /
• pp.51-57
• /
• 2011

This study was conducted to investigate the effects of supplementation diets of pine needle powder on performance, proximate composition, carcass characteristics, blood cholesterol concentration, TBARS (thiobarbituric acid reactive substance), WHC (water holding capacity), and shear force of chicken meat. Broiler chicks were fed diets for five weeks containing 0% pine needle powder (Control), 0.3% pine needle powder (T1), 0.6% pine needle powder (T2), and 0.9% pine needle powder (T3). Performance was no significant difference among treatment groups, but mortality was decreased in diets by the supplementation of pine needle powder than that of T1 and control. The moisture, crude protein, crude fat, and crude ash were no significant difference. The liver weight and abdominal fat was significantly decreased by the supplementation of pine needle powder compare to the T1 and control (P<0.05). The total cholesterol and LDL-cholesterol concentration of control was higher than treatment groups, and the HDL-cholesterol concentration and glucose of control was lower than treatment groups (P<0.05). The TBARS value was significantly decreased by the supplementation of pine needle compared to the control (P<0.05). In conclusion, these data indicate that 0.6% pine needle powder supplementation (T2) was most effective in decreasing mortality, total cholesterol and LDL-cholesterol and increasing HDL-cholesterol concentration.

• The Journal of Engineering Geology
• /
• v.23 no.3
• /
• pp.283-292
• /
• 2013

A calcareous rock slope failed during excavation of the slope for construction of a tunnel entrance. The slope is located at the construction site for widening highway in Yeongwol, Korea. Field surveys, laboratory tests, and numerical analyses were performed to determine the reason for the slope failure. The numerical analysis revealed that the safety factor of the slope before construction of the entrance was less than 1, and that this decreased after construction. After construction of the entrance, the sliding zone of the slope increased and slope stability decreased because the shear strain and plastic zone in the slope over the tunnel entrance showed an increase relative to the lower part of the slope. To enhance the stability of the slope for construction of the tunnel entrance, countermeasures such as rock bolts, rock anchors, and FRP (Fiber glass Reinforced Plastic) grouting were adopted in light of the field conditions. Serial field monitoring performed to confirm the reinforcing effects of the adopted countermeasures revealed a small amount of horizontal deformation of the slope soils, most of the elastic deformation that can regain its former value. In addition, the axial forces of the rock bolt and anchor were more strongly affected by slope excavation during construction of the tunnel entrance than by tunnel excavation or the rainy season, and the axial forces tended to converge after excavation of the tunnel. Therefore, we can confirm that the slope is currently safe.

• Journal of Korean Society of Steel Construction
• /
• v.19 no.1
• /
• pp.15-27
• /
• 2007

Over the past decade, labor costs have increased relative to the cost of material hardware according to analysts in the construction industry. Therefore, the minimum weight design, which has been widely adopted in the literature for the optimal design of steel structures, is no longer the most economical construction approach. Presently, although connection- related costs is crucial in determining the most cost-effective steel structures, most studies on this subject focused on minimum-weight design or engaged in higher analysis. Therefore, in this study, we proposed a fabrication scheme for the most cost-effective moment-resisting steel frame structures that resist lateral loads without compromising overall stability. The proposed approach considers the cost of steel products, fabrication, and connections within the design process. The optimal design considered construction realities, with the optimal trade-off between the number of moment connections and total cost was achieved by reducing the number of moment connections and rearranging them using the combination of analysis that includes shear, displacement and interaction value based on the LRFD code and optimization scheme based on genetic algorithms. In this study, we have shown the applicability and efficiency in the examples that considered actual loading conditions.

• Journal of Korean Society of Water and Wastewater
• /
• v.34 no.3
• /
• pp.211-220
• /
• 2020

When domestic sewage and rainwater runoff are discharged into a single sewer pipe, it is called a "combined sewer system." The sewage design standards in Korea specify the flow velocity based only on the volume of rainfall; therefore, sedimentation occurs on non-rainy days owing to the reduced flow rate and velocity. This sedimentation reduces the discharge capacity, causes unpleasant odors, and exacerbates the problem of combined sewer overflow concentration. To address this problem, the amount of sewage on non-rainy days, not just the volume of rainfall, should also be considered. There are various theories on sedimentation in sewer movement. This study introduces a self-cleansing velocity based on tractive force theory. By applying a self-cleansing velocity equivalent to the critical shear stress of a sand particle, sedimentation can be reduced on non-rainy days. The amount of sewage changes according to the water use pattern of citizens. The design hourly maximum wastewater flow was considered as a representative value, and the velocity of this flow should be more than the self-cleansing velocity. This design method requires a steeper gradient than existing design criteria. Therefore, the existing sewer pipelines need to be improved and repaired accordingly. In this study, five types of improvement and repair methods that can maximize the use of existing pipelines and minimize the depth of excavation are proposed. The key technologies utilized are trenchless sewer rehabilitation and complex cross-section pipes. Trenchless sewer rehabilitation is a popular sewage repair method. However, it is complex because the cross-section pipes do not have a universal design and require continuous research and development. In an old metropolis with a combined sewer system, it is difficult to carry out excavation work; hence, the methods presented in this study may be useful in the future.

• Food Science of Animal Resources
• /
• v.25 no.3
• /
• pp.265-270
• /
• 2005

This study was carried out to investigate the effects of washing times on quality characteristics of chicken breast surimi. The surimi was prepare after 2 (C), 4 (T1) and 6 (T2) times washed with a ratio 6 : 1 distilled water-chicken breast meat. The moisture and crude protein content of T1 and T2 were higher than that of C. The myofibrillay protein and yield of C was higher (p<0.05) than those of T1 and T2. The pH of C was higher (p<0.05) compare to other treatments. The WHC was no significant differences between the all treatments. The shear force of all treatments were tended to higher as washing times increased. The breaking force and deformation value of T2 were lower than other treatments. The $L^{*}$ values in C and $b^{\ast}$ values in T1 were significantly (p<0.05) lower among the treatments group. The hardness and gumminess of T1 was higher (p<0.05) compared to T2. The springiness of treatments increased as washing times increased. The sensory score of surimi made from chicken breast meat was not affected by the washing times.

• Food Science of Animal Resources
• /
• v.38 no.3
• /
• pp.606-614
• /
• 2018

It is important to understand how marbling traits and tenderness differ among beef steaks from the carcass grading site and other regions within the longissimus thoracis (LT) muscle, as these characteristics are closely associated with consumer acceptability and willingness to purchase. Thus, the aim of this study was to compare the marbling fleck traits and objective tenderness parameters in the groups classified by the coarseness index (CI) of marbling fleck (high and low groups) at the carcass grading site ($13^{th}$ thoracic vertebra; 13T) and three different locations (13T, 9T, and 6T) within the LT muscle from well-marbled (marbling score 7 to 9) Hanwoo steer. Image analysis showed that the longitudinal locations had a significant effect on marbling fleck traits. The total area of large marbling fleck divided by the total marbling area (coarseness) was higher at the central region (13T to 12T) compared to the front thoracic region (6T to 5T) in the high CI group (0.23 vs. 0.17, p<0.05), whereas no significant differences were observed in the total number of marbling fleck within the LT muscle in the high or low CI groups (p>0.05). Location effect on objective tenderness parameters within the LT muscle was somewhat limited, although the high CI group had a lower Warner-Bratzler shear force (WBS) value than did the low group (p<0.05). Taken together, the degree of coarseness of marbling fleck decreased from the carcass grading site to the front thoracic site, whereas the objective tenderness parameters, including WBS and hardness, of the grading site did not differ from the other regions within the LT muscle.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.30 no.3
• /
• pp.295-303
• /
• 2012

Clarify wind energy productivity depends on three factors: the wind probability density function(PDF), the turbine's power curve, and the air density. The wind PDF gives the probability that a variable will take on the wind speed value. Wind shear refers to the change in wind speed with height above ground. The wind speed tends to increase with the height above ground. also, Wind PDF refers to the change with height above ground. Wind analysts typically use the Weibull distribution to characterize the breadth of the distribution of wind speeds. The Weibull distribution has the two-parameter: the scale factor c and the shape factor k. We can use a linear least squares algorithm(or Ln-least method) and moment method to fit a Weibull distribution to measured wind speed data which data was located same site and different height. In this study, find that the scale factor is related to the average wind speed than the shape factor. and also different types of terrain are characterized by different the scale factor slop with height above ground. The gross turbine power output (before accounting for losses) was caculated the power curve whose corresponding air density is closest to the air density. and air desity was choose two way. one is the pressure of the International Standard Atmosphere up to an elevation, the other is the measured air pressure and temperature to calculate the air density. and then each power output was compared.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.1
• /
• pp.40-47
• /
• 2018

Porous walkway blocks are constructed for the purpose already, but reserved water is easily consumed due to the bigger permeability than necessary. Furthermore, porous structure reduces the strength of blocks, which resulting cracking and settlements in walkways. In this study, we suggested a solution for given problems by determination for the location of minimum principal stress in walkway blocks against moving foot loads in order to design and verifying the determined location of minimum principal stress. An optimum design with a verification example for determined location of minimum principal stress have been presented in a two dimensional Block member on elastic foundation for pedestrian walkway for reserving water inside. The minimum value for sum of shear forces is found when ${\times}1$ is 58.58 mm(30% of total span, 200mm), while the minimum deformation is located at ${\times}2=80mm$(70% of total span, 200 mm). In a modified model, When moving boundary condition(walkway foot loads) is located at ${\times}1$(=0 mm), the location of minimum principal stresses is found at 168 mm( 84% of span, 200 mm), in which the stress concentration due to the foot load is modeled as two layers of distributed loads(reactions of foundation modeled as springs). Consequently, zero deformed reservoirs for rainwater on the neutral axis (${\times}2=167mm$) has been determined in the modified model with three dimensional FEM analysis verifications.

• Food Science of Animal Resources
• /
• v.24 no.4
• /
• pp.393-398
• /
• 2004

To investigate the effect of dietary mugwort pellet on the growing performance and meat quality barrow (T1) and boar (T2) were alloted into six treatments : 1) commercial feed, 2) T1-1 and T2-1 (commercial feed supplemented with 3.0％ mugwort pellet), 3) T1-2 and T2-2 (commercial feed supplemented with 5.0％ mugwort pellet). They were fed experimental diets for 60 days before slaughtered. Meat samples were taken in wrap package and stored at 4$\pm$1$^{\circ}C$. Daily gain in both groups (T1 and T2) were higher than those of the control (p<0.05). Feed conversion tended to be lower in barrow group than boar group and tended to be decreased according to supplementation of mugwort pelleted diet in barrow group. In both barrow and boar groups, proximate compositions of pork were not sigificantly different, except for crude fat. Crude fat content was tended to be low in barrow when fed mugwort pelleted diet. Shear force value and sensory properties were siginificantly higher in barrow group than in boar group (p<0.05) and these results were also seemed due to great fed mugwort pelleted aiet(p<0.05). In the barrow group, values of tenderness and flavor were the highest in pigs fed diet supplemented with 3.0％ mugwort. The catechin content of pork tended to be higher in boar group than in barrow group and catechin tended to increase with supplementation of mugwort in the diet.

• Food Science of Animal Resources
• /
• v.26 no.2
• /
• pp.189-196
• /
• 2006

To investigate the effects of stretching and temperature of pre-rigor muscle on sarcomere length and tenderness of beef, hot boned M. Iongissimus dorsi thoracis were stretched or non-stretched, and stored at $0^{\circ}C$ for 48 hrs ($0^{\circ}C$ stretched and $0^{\circ}C$ non-stretched) or at $10^{\circ}C$ for 7 hrs followed by $0^{\circ}C$ for 41 hrs ($10^{\circ}C$ stretched and $10^{\circ}C$ non-stretched). There was no significant difference in muscle pH and drip loss between $10^{\circ}C$ stretched and $10^{\circ}C$ non-stretched samples, but they were significantly (p<0.05) lower in pH and drip loss than $0^{\circ}C$ stretched and $0^{\circ}C$ non-stretched samples. Stretched muscles at $0^{\circ}C$ showed significantly (p<0.05) higher cook loss than control muscles. Sarcomere length of $10^{\circ}C$ stretched muscle was significantly (p<0.05) longer than that of control. However, control muscle showed significantly (p<0.05) higher value of shear force at 2 and 14 days postmortem compared to that of $10^{\circ}C$ stretched muscle. Panels rated $10^{\circ}C$ stretched muscle as having a significantly (p<0.05) better tenderness, flavor and overall acceptability compared to those of control muscle. Results suggest that longer sarcomere length and tender beef could be obtained by stretching of pre-rigor muscle and storing it at $10^{\circ}C$ for 7 hrs followed by $0^{\circ}C$ for 41 hrs.