• Journal of Animal Science and Technology
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• v.63 no.3
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• pp.545-562
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• 2021

A 3 yr experiment was conducted to evaluate the influence of diet and feeding location on animal performance, carcass characteristics, whole blood counts, and internal parasite burden of lambs assigned to 1 of 4 treatments: 1) confinement fed 71% alfalfa, 18% barley pellet, 5% molasses, 0.013% Bovatec, 6.1% vitamin/mineral package diet (CALF), 2) confinement fed 60% barley, 26% alfalfa pellet, 4% molasses, 2.5% soybean-hi pro, 0.016% Bovatec, 7.4% vitamin/mineral package diet (CBAR), 3) field fed 71% alfalfa, 18% barley pellet, 5% molasses, 0.013% Bovatec, 6.1% vitamin/mineral package diet (FALF), and 4) field fed 60% barley, 26% alfalfa pellet, 4% molasses, 2.5% soybean-hi pro, 0.016% Bovatec, 7.4% vitamin/mineral package diet (FBAR). A year × location interaction was detected for ending body weight (BW), average daily gain (ADG), and dry matter intake (DMI); therefore results are presented by year. In all years, cost of gain and DMI were greater for CALF and FALF than for CBAR and FBAR feed treatments (p ≤ 0.03). In yr 2 and 3 field treatments had greater ending BW and ADG than confinement treatments. For all years, diet did not affect ending BW or ADG. In yr 1 dressing percent and rib eye area were greater for field finished lambs than confinement finished (p ≤ 0.02) and Warner-Bratzler shear force was greater for CALF and FALF (p = 0.03). In yr 2 lambs in FALF and FBAR treatments had greater leg scores and conformation than CALF and CBAR (p = 0.09). In yr 1, FALF had a greater small intestine total worm count than all other treatments. In yr 1, ending Trichostrongyle type egg counts were greater for FALF (p = 0.05). In yr 2, ending Nematodirus spp. egg counts were greater for FALF and lowest for CBAR (p < 0.01). Abomasum Teladorsagia circumcinta worm burden was greater in CALF than all other treatments (p = 0.07) in yr 2. While field finishing lambs with a grain- or forage-based diet we conclude that it is possible to produce a quality lamb product without adverse effects to animal performance, carcass quality or increasing parasite burdens.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.1
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• pp.13-29
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• 2021

A 3-D hydrodynamic model is applied in the Han River Estuary system, Gyeonggi Bay, to understand the mechanisms of salt transport. The model run is conducted for 245 days (January 20 to September 20, 2020), including dry and wet seasons. The reproducibility of the model about variation of current velocity and salinity is validated by comparing model results with observation data. The salt transport (FS) is calculated for the northern and southern part of Yeomha channel where salt exchange is active. To analyze the mechanisms of salt transport, FS is decomposed into three components, i.e. advective salt transport derived from river flow (QfS0), diffusive salt transport due to lateral and vertical shear velocity (FE), and tidal oscillatory salt transport due to phase lag between current velocity and salinity (FT). According to the monthly average salt transport, the salt in both dry and wet seasons enters through the southern channel of Ganghwa-do by FT. On the other hand, the salt exits through the eastern channel of Yeongjong-do by QfS0. The salt at Han River Estuary enters towards the upper Han River by FT in dry season, whereas that exits to the open sea by QfS0 in wet season. As a result, mechanisms of salt transport in the Han River Estuary depend on the interaction between QfS0 causing transport to open sea and FT causing transport to the upper Han River.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.5
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• pp.300-313
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• 2014

Most analytical solutions for wave-induced soil response have been mainly developed to investigate the influence of the progressive and standing waves on the seabed response in an infinite seabed. This paper presents a new analytical solution to the governing equations considering the wave-induced soil response for the partial standing wave fields with arbitrary reflectivity in a porous seabed of finite thickness, using the effective stress based on Biot's theory (Biot, 1941) and elastic foundation coupled with linear wave theory. The newly developed solution for wave-seabed interaction in seabed of finite depth has wide applicability as an analytical solutions because it can be easily extended to the previous analytical solutions by varying water depth and reflection ratio. For more realistic wave field, the partial standing waves caused by the breakwaters with arbitrary reflectivity are considered. The analytical solutions was verified by comparing with the previous results for a seabed of infinite thickness under the two-dimensional progressive and standing wave fields derived by Yamamoto et al.(1978) and Tsai & Lee(1994). Based on the analytical solutions derived in this study, the influence of water depth and wave period on the characteristics of the seabed response for the progressive, standing and partial standing wave fields in a seabed of finite thickness were carefully examined. The analytical solution shows that the soil response (including pore pressure, shear stress, horizontal and vertical effective stresses) for a seabed of finite thickness is quite different in an infinite seabed. In particular, this study also found that the wave-induced seabed response under the partial wave conditions was reduced compared with the standing wave fields, and depends on the reflection coefficient.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.1
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• pp.49-64
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• 2014

Seabed beneath and near the coastal structures may undergo large excess pore water pressure composed of oscillatory and residual components in the case of long durations of high wave loading. This excess pore water pressure may reduce effective stress and, consequently, the seabed may liquefy. If the liquefaction occurs in the seabed, the structure may sink, overturn, and eventually fail. Especially, the seabed liquefaction behavior beneath a gravity-based structure under wave loading should be evaluated and considered for design purpose. In this study, to evaluate the liquefaction potential on the seabed, numerical analysis was conducted using 2-dimensional numerical wave tank. The 2-dimensional numerical wave tank was expanded to account for irregular wave fields, and to calculate the dynamic wave pressure and water particle velocity acting on the seabed and the surface boundary of the structure. The simulation results of the wave pressure and the shear stress induced by water particle velocity were used as inputs to a FLIP(Finite element analysis LIquefaction Program). Then, the FLIP evaluated the time and spatial variations in excess pore water pressure, effective stress and liquefaction potential in the seabed. Additionally, the deformation of the seabed and the displacement of the structure as a function of time were quantitatively evaluated. From the analysis, when the shear stress was considered, the liquefaction at the seabed in front of the structure was identified. Since the liquefied seabed particles have no resistance force, scour can possibly occur on the seabed. Therefore, the strength decrease of the seabed at the front of the structure due to high wave loading for the longer period of time such as a storm can increase the structural motion and consequently influence the stability of the structure.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.35-41
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• 2007

This study was conducted to determine the effect of pH adjustment and addition of sodium chloride (NaCl) on quality characteristics of pork leg surimi. The pork leg surimi was manufactured with one of following pH 3.0 or pH 11.0 adjustment and contained 2% NaCl or not; C (Alaska pollack surimi, two times washing, 0% NaCl), T1 (pork leg surimi pH 3.0 adjustment, 0% NaCl), T2 (pork leg surimi, pH 3.0 adjustment, 2% NaCl), T3 (pork leg surimi, pH 11.0 adjustment 0% NaCl), T4 (pork leg surimi, pH 11.0 adjustment, 2% NaCl). The $L^*$ and W values was increased with increasing of pH value, but the $a^*$ and $b^*$ values lower. The W values were higher (p<0.05) as addition of NaCl, but $a^*$ and $b^*$ values were lower. In textural properties, the cohesiveness was increased with increasing of pH value, however with the exception of springiness all traits were higher (p<0.05) as addition of NaCl. The breaking force and gel strength was increased with increasing of pH value. The breaking force, gel strength and breaking force u deformation were higher as addition of NaCl, but shear force lower. In sensory evaluation, the tenderness was increased with increasing of pH value and all traits of sensory evaluation also were higher (p<0.05) as addition of NaCl. There were no differences in interaction of pH adjustment and without or with NaCl on color, textural properties, breaking force, deformation, gel strength, shear force and sensory evaluation of pork leg surimi. The color, textural and physical characteristics and sensory evaluation ot T2 and T4 were similar to treatment C. Therefore, the pH 11.0 and 2% NaCl addition on process of manufacture of pork leg surimi would be recommended.

• Economic and Environmental Geology
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• v.47 no.4
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• pp.317-333
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• 2014

The Pocheon iron (-copper) deposit, located at the northwestern part of the Precambrian Gyeonggi massif in South Korea, genetically remains controversial. Previous researchers advocated a metamorphosed (-exhalative) sedimentary origin for iron enrichment. In this study, we present strong evidences for skarnification and Fe mineralization, spatially associated with the Myeongseongsan granite. The Pocheon deposit is composed of diverse carbonate rocks such as dolostone and limestone which are partially overprinted by various hydrothermal skarns such as sodic-calcic, calcic and magnesian skarn. Iron (-copper) mineralization occurs mainly in the sodic-calcic skarn zone, locally superimposed by copper mineralization during retrograde stage of skarn. Age data determined on phlogopites from retrograde skarn stage by Ar-Ar and K-Ar methods range from $110.3{\pm}1.0Ma$ to $108.3{\pm}2.8Ma$, showing that skarn iron mineralization in the Pocheon is closely related to the shallow-depth Myeongseongsan granite (ca. 112 Ma). Carbon-oxygen isotopic depletions of carbonates in marbles, diverse skarns, and veins can be explained by decarbonation and interaction with an infiltrating hydrothermal fluids in open system ($XCO_2=0.1$). The results of sulfur isotope analyses indicate that both of sulfide (chalcopyrite-pyrite composite) and anhydrites in skarn have very high sulfur isotope values, suggesting the $^{34}S$ enrichment of the Pocheon sulfide and sulfate sulfur was derived from sulfate in the carbonate protolith. Shear zones with fractures in the Pocheon area channeled the saline, high $fO_2$ hydrothermal fluids, resulting in locally developed intense skarn alteration at temperature range of about $500^{\circ}$ to $400^{\circ}C$.

• Economic and Environmental Geology
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• v.47 no.4
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• pp.335-349
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• 2014

The Pocheon skarn deposit, located at the northwestern part of the Precambrian Gyeonggi massif in South Korea, occurs at the contact between the Cretaceous Myeongseongsan granite and the Precambrian carbonate rocks, and is also controlled by N-S-trending shear zone. The skarn distribution and mineralogy reflects both structural and lithological controls. Three types of skarn formations based on mineral assemblages in the Pocheon skarn exist; a sodiccalcic skarn and a magnesian skarn mainly developed in the dolostone, and a calcic skarn developed in the limestone. Iron mineralization occurs in the sodic-calcic and magnesian skarn zone, locally superimposed by copper mineralization during retrograde skarn stage. The sodic-calcic skarn is composed of acmite, diopside, albite, garnet, magnetite, maghemite, anhydrite, apatite, and sphene. Retrograde alteration consists of tremolite, phlogopite, epidote, sericite, gypum, chlorite, quartz, calcite, and sulfides. Magnesian skarn mainly consists of diopside and forsterite. Pyroxene and olivine are mainly altered to tremolite, with minor phlogopite, talc, and serpentine. The calcic skarn during prograde stage mainly consists of garnet, pyroxene and wollastonite. Retrograde alteration consists of epidote, vesuvianite, amphibole, biotite, magnetite, chlorite, quartz, calcite, and sulfides. Microprobe analyses indicate that the majority of the Pocheon skarn minerals are enriched by Na-Mg composition and have high $Fe^{3+}/Fe^{2+}$, $Mg^{2+}/Fe^{2+}$, and $Al^{3+}/Fe^{2+}$ ratios. Clinopyroxene is acmitic and diopsidic composition, whereas garnet is relatively grossular-rich. Amphiboles are largely of tremolite, pargasite, and magnesian hastingsite composition. The prograde anhydrous skarn assemblages formed at about $400^{\circ}{\sim}500^{\circ}C$ in a highly oxidized environment ($fO_2=10^{-23}{\sim}10^{-26}$) under a condition of about 0.5 kbar pressure and $X(CO_2)=0.10$. With increasing fluid/rock interaction during retrograde skarn, epidote, amphibole, sulfides and calcite formed as temperature decreased to approximately $250^{\circ}{\sim}400^{\circ}C$ at $X(CO_2)=0.10$.

• Journal of the Korean earth science society
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• v.37 no.4
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• pp.218-229
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• 2016

The bedform stability diagram indicates the shape and size of bedforms that will occur to a given grain size and flow velocity. The diagram has been constructed from experimental data which have been mostly acquired by flume experiments. Generally, the flume experiments have been performed on well sorted sediments with unimodal grain size distribution, in order to understand relationship between grain size and flow velocity. According to the diagram, a ripple structure initiates to be formed from lower flow regime flat bed, as the flow velocity increases on the surface of fine-sand or medium-sand sediments. This study aims to verify that the experimental result of bedform stability diagram will be reproduced in our flume experimental systems, and also to confirm that the result is consistent not only on well-sorted sand sediments but also on poorly-sorted sand sediments with bimodal grain size distribution. The experimental results in this study show that initiation of 2D or 3D ripple structure on poorly-sorted sand sediments requires higher flow velocity and shear stress than those for initiation of the structure on well-sorted sand sediments. In general, carbonate sediments are characterized by poor sorting due to inactive hydraulic sorting and bimodal grain size distribution with allochems and matrices. The results suggest that the carbonate depositional system possibly need a higher flow velocity for initial formation of 2D or 3D bedform structures. The reason might be the fact that pulling off and lifting of a grain in poorly sorted sediments require more energy due to sorting, friction, stabilization, armour effects, and their complex interaction. This preliminary study warrants additional experiments under various conditions and more accurate analysis on the relationship between formation of bedforms and grain size distribution.

• The Journal of the Petrological Society of Korea
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• v.13 no.1
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• pp.34-45
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• 2004

This paper describes the textural relations of mantle xenoliths and fluid inclusions in mantle-derived rocks found in alkaline basalts from Jeju Island which contain abundant ultramafic, felsic, and cumulate xenoliths. Most of the ultramafic xenoliths are spinel-lherzolites, composed of olivine, orthopyroxene, clinopyroxene and spinel. The felsic xenoliths considered as partially molten buchites consist of quartz and plagioclase with black veinlets, which are the product of ultrahigh-temperature metamorphism of lower crustal materials. The cumulate xenoliths, clinopyroxene-rich or clinopyroxene megacrysts, are also present. Textural examination of these xenoliths reveals that the xenoliths are typically coarse grained with metamorphic characteristics, testifying to a complex history of evolution of the lower crust/upper mantle source region. The ultramafic xenoliths contain protogranular, porphyroclastic and equigranular textures with annealing features, indicating the presence of shear regime in upper mantle of the Island. The preferential associations of spinel and olivine with large orthopyroxenes suggest a previous high temperature equilibrium in the high-Al field and the original rock-type was a Al-rich orthopyroxene-bearing peridotite without garnet. Three types of fluid inclusions trapped in mantle-derived xenoliths include CO$_2$-rich fluid (Type I), multiphase silicate melt (glass ${\pm}$ devitrified crystals ${\pm}$ one or more daughter crystals ＋ one or more vapor bubbles) (Type II), and sulfide (melt) inclusions (Type III). C$_2$-rich inclusions are the most abundant volatile species in mantle xenoliths, supporting the presence of a separate CO$_2$-rich phase. These CO$_2$-rich inclusions are spatially associated with silicate and sulfide melts, suggesting immiscibility between them. Most multiphase silicate melt inclusions contain considerable amount of silicic glass. reflecting the formation of silicic melts in the lower crust/upper mantle. Combining fluid and melt inclusion data with conventional petrological and geochemical information will help to constrain the fluid regime, fluid-melt-mineral interaction processes in the mantle of the Korean Peninsula and pressure-temperature history of the host xenoliths in future studies.

• Korean Journal of Organic Agriculture
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• v.19 no.2
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• pp.199-214
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• 2011

This study was conducted to investigate the effect of organic dietary metabolizable energy (ME) and crude protein (CP) on productivity, meat quality and blood composition of crossbred chicks (hanhyub 3 ho) for different growring periods. Experiments were factorially designed with ME 3,000, 3,100kcal/kg and CP 21, 22, 23% for starter (0-4wks); ME 3,100, 3,150, 3,200kcal/kg and CP 18, 19, 20% for grower (5-8wks); ME 3,100, 3,150, 3,200kcal/kg and CP 15, 16, 17% for finisher (9-10wks). The total number of chicks and replicate of each treatment for starter, grower, finisher were 720, 4; 702, 6; 468, 4, respectively. The diets was mixed with more 90% organic feed ingredients. The productivity were not influence by dietary ME for starting period. Weight gain and feed intake were significantly increased in CP 23% treatment than CP 21, 22% treatment (P<0.05). FCR was improved as dietary CP increased (P<0.05). Weight gain was tended to be increased by decreaing ME content and increasing CP contents for growing period. Feed intake showed no difference among the ME and CP treatment groups. FCR improved significantly in CP 19, 20% compared with CP 18% (P<0.05). Weight gain was not significantly different between ME and CP treatments for finishing period. Feed intake was lower in ME 3,150, 3,200kcal/kg than the ME 3,100 kcal/kg treatment (P<0.05). FCR was higher in ME 3,100kcal/kg than ME 3,150, 3,200kcal/kg treatment (P<0.05). Interaction on productivity was not exited between ME and CP treatment groups for different feeding periods. There was no difference in the total protein, albumin, glucose and triglyceride amount in blood depending on dietary ME and CP contents. Total cholesterol was greatly decreased in ME 3,100kcal/kg than the ME 3,200kcal/kg (P<0.05), but not different between CP treatments. Cooking loss of breast meat was lower in ME 3,150kcal/kg than the ME 3,200kcal/kg (P<0.05). Moisture, shear force and pH were not statistically different among treatments. Protein solubility was increased by increasing ME and CP in diets. The collagen was tended to increase as dietary ME increased. Redness was remarkably higher in ME 3,150kcal/kg than the ME 3,100kcal/kg (P<0.05). Yellowness of meat fed ME 3,150kcal/kg showed significantly lower than other treatments (P<0.05). Therefore, the optium ME and CP to improve the productivity for each period were 3,000kcal/kg, 23%; 3,100kcal/kg, 19%; 3,150kcal/kg, CP 16%, repectively.