• Food Science of Animal Resources
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• v.38 no.5
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• pp.936-949
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• 2018

Changes in microbial community and physicochemical traits of chicken summer sausage made from spent layer thigh added with different level (0%, 0.1%, 0.3%, and 0.5% w/w) of ground chopi (Zanthoxylum piperitum) during manufacture were analyzed. The microbial community was profiled and analyzed by sequencing 16S rRNA gene using Illumina MiSeq. Samples were taken from raw sausage batter, after 15 h of fermentation, 8 h of cooking including cooling down, and 7 d of drying. The final pH of the sausage was reduced by the addition of ground chopi. However, no clear effect on water activity was observed. Ground chopi inhibited the development of red curing color after fermentation as it exhibited antimicrobial effect. However, the effect on species richness and microbial composition after cooking was unclear. Ground chopi delayed lipid oxidation during manufacture and the effect was dependent on the addition level. Fermentation reduced the species richness with a dominancy of lactic acid bacteria. The profile of microbiota in the raw batter was different from other stages, while the closest relationship was observed after cooking and drying. Proteobacteria was predominant, followed by Firmicutes and Bacteroidetes in raw samples. Firmicutes became dominating after fermentation and so forth, whereas other predominant phylum decreased. At genus level, unclassified Lactobacillales was the most abundant group found after fermentation and so forth. Therefore, the overall microbial composition aspects were mainly controlled during fermentation by the abundance of lactic acid bacteria, while bacterial counts and lipid oxidation were controlled by cooking and the addition of ground chopi.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.380-387
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• 2015

A lead slowing-down spectrometer (LSDS) system is a promising nondestructive assay technique that enables a quantitative measurement of the isotopic contents of major fissile isotopes in spent nuclear fuel and its pyroprocessing counterparts, such as $^{235}U$, $^{239}Pu$, $^{241}Pu$, and, potentially, minor actinides. The LSDS system currently under development at the Korea Atomic Energy Research Institute (Daejeon, Korea) is planned to utilize a high-flux ($>10^{12}n/cm^2{\cdot}s$) neutron source comprised of a high-energy (30 MeV)/high-current (~2 A) electron beam and a heavy metal target, which results in a very intense and complex radiation field for the facility, thus demanding structural shielding to guarantee the safety. Optimization of the structural shielding design was conducted using MCNPX for neutron dose rate evaluation of several representative hypothetical designs. In order to satisfy the construction cost and neutron attenuation capability of the facility, while simultaneously achieving the aimed dose rate limit (< $0.06{\mu}Sv/h$), a few shielding materials [high-density polyethylene (HDPE)eBorax, $B_4C$, and $Li_2CO_3$] were considered for the main neutron absorber layer, which is encapsulated within the double-sided concrete wall. The MCNP simulation indicated that HDPE-Borax is the most efficient among the aforementioned candidate materials, and the combined thickness of the shielding layers should exceed 100 cm to satisfy the dose limit on the outside surface of the shielding wall of the facility when limiting the thickness of the HDPE-Borax intermediate layer to below 5 cm. However, the shielding wall must include the instrumentation and installation holes for the LSDS system. The radiation leakage through the holes was substantially mitigated by adopting a zigzag-shape with concrete covers on both sides. The suggested optimized design of the shielding structure satisfies the dose rate limit and can be used for the construction of a facility in the near future.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.7
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• pp.946-951
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• 2010

The objective of this research was to evaluate the effects of dietary supplementation of blood meal (BM) as a source of histidine, and magnesium oxide (MgO) as a catalyst of carnosine synthetase, on carnosine (L-Car) content in the chicken breast muscle (CBM), laying performance, and egg quality of spent old hens. Four hundred eighty laying hens (Hy-Line$^{(R)}$ Brown), 95wk old, were allotted randomly into five replicates of six dietary treatments: T1; 100% basal diet, T2; 100% basal diet+MgO, T3; 97.5% basal diet+2.5% BM, T4; 97.5% basal diet+2.5% BM+MgO, T5; 95% basal diet+5% BM, T6; 95% basal diet+5% BM+MgO. Magnesium oxide was added at 0.3% of diets. The layers were fed experimental diets for 5wk. There were no significant differences in the weekly L-Car content in CBM among all treatments during the total experimental period, but some of the contrast comparisions showed higher L-Car in CBM of T6. The L-Car contents linearly decreased (p<0.01 or p<0.05) as the layers got older except in T4 (p>0.05). There were significant differences in egg weight (p<0.01) and soft and broken egg ratio (p<0.05). The control (T1) was highest in egg weight and T6 was lowest in soft and broken egg ratio. Among the parameters of egg quality, there were significant differences in eggshell strength (p<0.01) and egg yolk color (p<0.05). Magnesium oxide supplementation increased the eggshell strength and BM tended to decrease egg yolk color. Eggshell color, eggshell thickness, and Haugh unit were not influenced by BM and MgO. In conclusion, BM and MgO did not significantly influence the L-Car in CBM of spent layers. The L-Car content rapidly decreased as the layers became senescent. Eggshell strength was increased by MgO supplementation.

• Development and Reproduction
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• v.20 no.3
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• pp.247-254
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• 2016

Cytological changes of the epithelial cells according to the developmenatal phases of the seminal vesicle related to the spermatogenic stages in the testicular lobules during spermagenesis in male Neptunea (Barbitonia) cumingii (Gastropoda: Buccinidae) were investigated monthly by electron microscopical and histological observations. N. (B) cumingii is dioecious, and an internal fertilization species. The male genital organ is located near the tentacles. The spermatozoon is approximatley $50{\mu}m$ in length. The axoneme of the tail flagellum consists of nine pairs of microtubles at the periphery and one pair at the center. The process of germ cell development during spermatogenesis can be divided into five succesive stages: (1) spermatogonia, (2) primary spermatocytes, (3) secondary spermatocytes, (4) spermatids, and (5) spermatozoa. A considerable amount of spermatozoa make their appearance in the testicular lobules (or acini) and some of them are tranported from the testis towards the seminal vesicles until late July. In this study, the developmental phases of the epithelial cells of the seminal vesicles of N. (B.) cumingii could be classified into four phases: (1) S-I phase (resting), (2) S-IIphase (early accumulating), (3) S-III phase (accumulating), and (4) S-IV phase (spent). However, in case of N. (B.) arthritica cumingii, the developmental phases of the seminal vesicle were devided into three phases: (1) resting, (2) accumulating and (3) spent. Granular bodies in the inner layer of the seminal vesicles are involved in resorption of digestion of residual spermatozoa.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.5-10
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• 2005

We deal with the sliding mode control using the time delay estimation. The time delay estimation is able to weaken the need for obtaining a quantitative plant model analogous to the real plant so the sliding mode control with a time delay estimation (SMCTE) is very suitable for plant such as SMA actuators whose quantitative model is difficult to obtain. We have already studied the application of the time delay control (TDC) to SMA actuators in other literature. Based on the previous study on the TDC, we developed the gain tuning method for the SMCTE, which results were nearly the same as the TDC. With respect to the step response, the SMCTE proved its predominance in a comparison with other control schemes such as the PID control and the relay control. As well as the contribution of the above control methodology, the model identification for SMA actuators has also been studied. The dynamics for an SMA actuator was newly derived using the modified Liang's model. The derived dynamics showed a continuity at the change of the phase transformation process but the original Liang's model could not.

• Corrosion Science and Technology
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• v.19 no.1
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• pp.1-7
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• 2020

Chalk River Unidentified Deposits (CRUDs) were collected from the Korean pressurized water reactor (PWR) plant (A, B, and C) where the axial offset anomaly (AOA) occurred. AOA, also known as a CRUD-induced power shift, is one of the key issues in maintaining stable PWR plant operations. CRUDs were sampled from spent nuclear fuel rods and analyzed using an electron probe micro-analyzer (EPMA). This paper describes the characteristics of boron-deposits from the CRUDs sampled from twice-burnt assemblies from the Korean PWR. The primary coolant of a PWR contains boron and lithium. It is known that boron deposition occurs in a thick CRUD layer under substantial sub-cooled nucleate boiling (SNB). The results of this study are summarized as follows. Boron was not found at the locations where the existence was confirmed in simulated CRUDs, in other words, the cladding and CRUD boundaries. Nevertheless, we clearly observed the presence of boron and confirmed that boron existed as a lump in crystalline form. In addition, the study confirmed that CRUD existed in a crystal form with a unique size of about 10 ㎛.

• Korean Journal of Materials Research
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• v.14 no.4
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• pp.251-259
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• 2004

In the development of the advanced spent fuel management process based on the molten salt technology, it is essential to choose the optimum material for the process equipment handling molten salt. Corrosion behavior of Ni 200 and Ni-base alloys in molten salt of LiCl-$Li_2$O under oxidation atmosphere was investigated in the temperature range of $650～800^{\circ}C$ for 24～312 hrs. The order of corrosion rate was Ni 200 > Inconel 690 > Inconel 601 > Inconel 600. Inconel 600 alloy showed the highest corrosion resistance among the examined alloys, but Ni 200 exhibited the highest corrosion rate. Corrosion products of Inconel 600 and Inconel 601 were $Cr_2$$O_3$ and $NiFe_2$$O_4$. In case of Inconel 690, a single layer of $CrO_2$$O_3$ was formed in the early stage of corrosion and an outer layer of $NiFe_2$O$_4$ and inner layer of $Cr_2$$O_3$ were formed with increase of corrosion time. Inconel 600 showed local corrosion behavior and Inconel 601, 690 showed uniform corrosion behavior.

• Korean Journal of Poultry Science
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• v.38 no.3
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• pp.197-204
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• 2011

To investigate the effects of Cordyceps ochraceostromat, silkworm cocoon and conjugated linoleic acid (CLA) addition on the quality of cremi during storage, this study was conducted. Cremis were prepared using a 20% spent layer breast recovered protein to replace Alaska pollack with the addition of 0.1% silkworm cocoon powder (T1), 0.05% silkworm cocoon powder + 0.05% Cordyceps ochraceostromat powder (T2), and 0.05% silkworm cocoon powder + 0.05% CLA. All manufactured cremis were vacuum-packaged, stored at $10{\pm}1^{\circ}C$ and finally evaluated for their quality on 0, 2, 4 and 6 weeks of storage. The pH, whiteness, gel strength and breaking force of cremis from T2 were higher than those of samples derived from either T1 or T3. However, cremis from T2 showed low shear force values when compared to other cremis (p<0.05). Therefore, the results indicate that cremis contained 0.05% silkworm cocoon powder and 0.05% Cordyceps ochraceostromat combination (T2) may be recommendable to induce customers to buy, thereby, it may be beneficial to both manufacturers and consumers in market.

• Korean Journal of Poultry Science
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• v.21 no.4
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• pp.239-247
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• 1994

A study was conducted to investigate the effects of the addition of varied levels of NaCi and phosphates on the physicochernical properties of the breast meat of the spent layers(2 \pm 0.2 kg) which were stabilized for over 24 h before slaughter. Within 1 h after slaughter, breast meats were removed and treated with NaGl(0, 1, 2, 3%) and phosphates(0.25% and 0.5%) using a hot-salted method. The breast meat was stored at 4 \pm $1^{\circ}C$ for 3 d. The results obtained were summarized as follows. 1. The pH values of salt-treated groups were significantly higher than that of the control(P<0.05) ; the higher the salt level, the higher the pH. The pH values were significantly increased in both control and treatment groups during storage(P<0.05). Among salt-treated groups, the 0.5% phosphates level showed significantly high pH(P<0.05) compared to other levels of salt groups. 2. The moisture contents were significantly lower in all salt4reated groups than the control(P<0.05), and showed a negative relationship with the levels of salt. It decreased in control group gradually as the storage period extended, but not significantly changed in salt-treated groups. 3. The shear force values in salt-treated groups were lower than that of the control and showed a negative relationship with salt levels. At a constant level of NaCI, the shear force value was higher in 0.25% phosphates level than in 0.5% level. It decreased in both control and salt-treated groups during storage. 4. The salt treatments tended to increase the sodium content proportionately. The sodium content decreased in both control and salt treatment groups during storage(P<0.05). In addition, the combination of high levels of NaCl and phosphates rather than those of low levels of NaCI and phosphates resulted in elevated levels of sodium. 5. The phosphorus contents in salt-treated groups were higher than that of control. Between 0.5% and 0.25% phosphates levels this value showed significant difference(P<0.05). Its contents in both control and treatment groups were significantly decreased during storage (P<0.05).