This study suggests a machine learning model for predicting the production quality of free-machining 303-series stainless steel small rolling wire rods according to the manufacturing process's operation condition. The operation condition involves 37 features such as sulfur, manganese, carbon content, rolling time, and rolling temperature. The study procedure includes data preprocessing (integration and refinement), exploratory data analysis, feature selection, machine learning modeling. In the preprocessing stage, missing values and outlier are removed, and variables for the interaction between processes and quality influencing factors identified in existing studies are added. Features are selected by variable importance index of lasso regression, extreme gradient boosting (XGBoost), and random forest models. Finally, logistic regression, support vector machine, random forest, and XGBoost is developed as a classifier to predict good or defective products with new operating condition. The hyper-parameters for each model are optimized using k-fold cross validation. As a result of the experiment, XGBoost showed relatively high predictive performance compared to other models with accuracy of 0.9929, specificity of 0.9372, F1-score of 0.9963 and logarithmic loss of 0.0209. In this study, the quality prediction model is expected to be able to efficiently perform quality management by predicting the production quality of small rolling wire rods in advance.

In this study, nano-scale copper powders were reduction treated in a hydrogen atmosphere at the relativelyhigh temperature of 350℃ in order to eliminate surface oxide layers, which are the main obstacles for fabricating anano/ultrafine grained bulk parts from the nano-scale powders. The changes in composition and microstructure beforeand after the hydrogen reduction treatment were evaluated by analyzing X-ray diffraction (XRD) line profile patternsusing the convolutional multiple whole profile (CMWP) procedure. In order to confirm the result from the XRD lineprofile analysis, transmitted electron microscope observations were performed on the specimen of the hydrogen reduc-tion treated powders fabricated using a focused ion beam process. A quasi-statically compacted specimen from the nano-scale powders was produced and Vickers micro-hardness was measured to verify the potential of the powders as thebasis for a bulk nano/ultrafine grained material. Although the bonding between particles and the growth in size of theparticles occurred, crystallites retained their nano-scale size evaluated using the XRD results. The hardness results dem-onstrate the usefulness of the powders for a nano/ultrafine grained material, once a good consolidation of powders isachieved.

In this study, nanocrystalline Cu-Ni bulk materials with various compositions were cold compacted by a shock compaction method using a single-stage gas gun system. Since the oxide layers on powder surface disturbs bonding between powder particles during the shock compaction process, each nanopowder was hydrogen-reduced to remove the oxide layers. X-ray peak analysis shows that hydrogen reduction successfully removed the oxide layers from the nano powders. For the shock compaction process, mixed powder samples with various compositions were prepared using a roller mixer. After the shock compaction process, the density of specimens increased up to 95% of the relative density. Longitudinal cross-sections of the shock compacted specimen demonstrates that a boundary between two powders are clearly distinguished and agglomerated powder particles remained in the compacted bulk. Internal crack tended to decrease with an increase in volumetric ratio of nano Cu powders in compacted bulk, showing that nano Cu powders has a higher coherency than nano Ni powders. On the other hand, hardness results are dominated by volume fraction of the nano Ni powder. The crystalline size of the shock compacted bulk materials was greatly reduced from the initial powder crystalline size since the shock wave severely deformed the powders.

In this study, nanocrystalline nickel powders were cold compacted by a dynamic compaction method usinga single-stage gas gun system. A bending test was conducted to measure the bonding strengths of the compacted regionsand microstructures of the specimen were analyzed using a scanning electron microscopy. The specimen was separatedinto two parts by a horizontal crack after compaction. Density test shows that the powder compaction occurred only inthe upper part of the specimen. Brittle fracture was occurred during the bending test of the compact sample. Dispersionof shock energy due to spalling highly affected the bonding status of the nanocrystalline nickel powder.

Bulk nanostructured copper was fabricated by a shock compaction method using the planar shock wavegenerated by a single gas gun system. Nano sized powders, average diameter of 100 nm, were compacted into the cap-sule and target die, which were designed to eliminate the effect of undesired shock wave, and then impacted with analuminum alloy target at 400 m/s. Microstructure and mechanical properties of the shock compact specimen were ana-lyzed using an optical microscope (OM), scanning electron microscope (SEM), and micro indentation. Hardness resultsshowed low values (approximately 45~80 Hv) similar or slightly higher than those of conventional coarse grained com-mercial purity copper. This result indicates the poor quality of bonding between particles. Images from OM and SEMalso confirmed that no strong bonding was achieved between them due to the insufficient energy and surface oxygenlayer of the powders.

중력분을 이용하여 제면한 후 가압가열, microwave 및 가 압가열과 microwave 병행 처리한 후, 생면 및 삶은 면의 품질 에 미치는 영향에 대하여 알아보았다. 생면의 pH는 microwave 1 min 처리구에서 무처리구와 유의적인 차이를 보이지 않았 으며, 수분 함량은 autoclave 50 min 처리구에서 무처리구와 유의적인 차이를 보이지 않았고, 그 외의 처리구에서는 모두 수분 함량이 감소함을 확인하였다. 면의 색도 측정 결과는 명 도는 무처리구에 비해 모든 처리구에서 감소하였으며, 적색 도는 microwave 1 min 처리구는 감소한 반면, 나머지 처리구 는 증가하였다. 황색도는 autoclave 50 min 처리구와 autoclave 50 min/microwave 1 min 병행 처리구에서 증가한 반면, 나머 지 물리적 처리구에서는 감소하였다. 삶은 면의 색도에서는 명도, 적색도, 황색도 모두에서 무처리구에 비하여 물리적 처 리구에서 증가한 값을 나타내었다. 물성 측정 결과는 경도, 부착성, 응집성, 검성, 복원성에서 무처리구와 비교시 microwave 1 min 처리구는 유의적으로 감소하였으며, 그 외 처리구에서 는 유의적으로 증가한 값을 나타내었다. 탄력성과 전단력은 모든 처리구에서 유의적으로 증가하였으며, 인장력은 가압가 열 30 min 처리구와 무처리구가 유의적인 차이를 보이지 않았으나, 나머지 물리적 처리구에서는 유의적으로 증가하였다. 관능 평가 결과는 생면의 경우 색 항목에서 물리적 처리구들 이 유의적으로 낮은 점수를 받았다. 맛, 질감, 향 항목에서는 무처리구와 물리적 처리구간 유의적 차이를 보이지 않았다. 전체적인 기호도에서는 microwave 1 min 처리구가 가장 높은 점수를 얻었으며, 가압가열(50 min)과 microwave(1 min) 병행 처리구는 무처리구와 비슷한 점수를 얻었다. 따라서 제면 후 가압가열 및 microwave 처리가 생면 및 삶은 면에 있어서 색 과 질감 항목을 보완, 개선시킨다면 알러겐성이 저감화된 면 을 제품화하는데 적합할 것으로 사료되어진다.

In this study, porous titanium samples were manufactured by space holder methods using two kinds of urea and sodium chloride space holders. Three-dimensional pore structures were obtained by a computed-tomography (CT) tech- nique and utilized for finite element analysis in order to investigate the mechanical properties. The CT-based finite ele- ment analyses were in better agreement with the experimental results than unit cell model-based analyses. Both the experimental and CT-based results showed the same tendency that the elastic modulus decreased with increasing the porosities. The total porosity of the bulk body plays a key role in determining the elastic modulus of porous materials.

This study was conducted to investigate the quality characteristics of the natural dishwashing liquid added with the mixture extracts of Curcuma Longa L. (CL), Morus alba (MA) and Ecklonia cava (EC) at various concentrations. The pH and lightness of the natural dishwashing liquid were reduced by adding the mixture extracts, while the turbidity was increased. The natural dish washing liquid added with mixture extracts was shown to display strong antimicrobial activities against L. monocytogenes compared to that of control. Also, it revealed that antioxidant activity was increased depending on concentrations. However, natural dishwashing liquid added with mixture extracts showed the low detergency efficiency. In sensory evaluation, the natural dishwashing liquid containing CL 0.5%, MA 0.25% and EC 0.25% was preferred than the control and it showed negative result in skin patch test. These results suggest that the addition of CL 0.5%, MA 0.25% and EC 0.25% positively improved the qualities characteristics in the natural dish washing liquid.

Inflammation is the first response of the immune system to infection or irritation in our body. The use of medicinal plants has been widely applied as an alternative source for drug development. One of marine natural resources, the anti-inflammatory effect of Ishige sinicola ethanol extract (ISEE), was evaluated by using LPS-induced RAW 264.7 cell and mice model. As a result, the production of nitric oxide (NO) and pro-inflammatory cytokines (IL-6, IL-1β, TNF-α) were inhibited with increasing concentration of ISEE without any cytotoxicity. Furthermore, ISEE suppressed the expression of not only inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor-kappa B (NF-κB) p65, and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK) 1/2, p38, and c-Jun N-terminal kinase (JNK) in a dose-dependent manner. In mice ear edema test, the formation of edema was reduced at the highest dosage of ISEE and the reduction of the number of infiltrated mast cells was observed in histological analysis. These results indicate that ISEE has a potent anti-inflammatory activity and can be used as a pharmaceutical material for many kinds of inflammatory disease.

In this study, beauty food activities were determined for extracts of Saurus chinensis as functional beauty food. Tyrosinase inhibitory effect was increased as more 4 folds by ultra-fine grind technology than normal grind technology in ethanol extracts from Saurus chinensis. A ultra-fine ground technology was used to increase the extraction yield for bioactive compounds from medicinal plants. Tyrosinase inhibitory activity, which is related to skin-whitening, was confirmed to be 100% for ethanol extracts at 1,000 ppm of phenolics. Anti-wrinkle activity was determined showing 30% of inhibition effect at above 1,000 ppm phenolic concentration. The elastase inhibitory activity of water and ethanol extracts from ultra-fine ground Saurus chinensis showed higher inhibition activity than compared to extracts from normal ground Saurus chinensis. Astringent activity in ethanol extracts was determined showing over 70% at 250 ppm of phenolics. Based on these results, Saurus chinensis extracts can be used as a functional beauty food and cosmetic with whitening, anti-wrinkle and pore contraction effects.

In this study, the antioxidative activity and functional food activities of water and ethanol extracts from Pinus densiflora root were examined. It was more effective to use ethanol than water when extracting phenolic compounds. The extracted phenolic compounds from Pinus densiflora root for biological activities were examined. The phenolic compounds extracted with water and 80% EtOH were 1.86±0.04 mg/g and 6.85±0.16 mg/g, respectively. DPPH free radical scavenging activity of water and EtOH were each 86% and 85% at 100 μg/mL phenolics, respectively. ABTS radical decolorization activity was 48% in water and 68% in EtOH at 200 μg/mL. Antioxidant Protection Factor (PF) were 1.74 PF in water and 1.96 PF in EtOH at 50 μg/mL. TBARs of water and EtOH were 93% and 98%, respectively at 100 μg/mL. The inhibition activity on xanthine oxidase was 83.7% in water extracts and 79.6% in ethanol extracts. Inhibition on xanthine oxidase of water and ethanol extracts showed a higher inhibition effect than allopurinol. The inhibition activity on α-glucosidase was 14.8% in water extracts and 91.6% in ethanol extracts. The result suggests that P. densiflora root extracts may be useful as as functional food material.

본 연구에서는 감마선 조사가 떫은감 과육의 세포벽변화, 수렴성 및 경도변화에 미치는 영향을 살펴보았다. 감마선 조사 결과 떫은감 과육 중의 가용성 탄닌 함량의 변화는 대조구의 181.04±1.72 μg/g에 비해 처리 방사선의 양이 5～20 kGy로 증가할수록 146.31 μg/g에서 128.09 μg/g으로 과육내의 가용성 탄닌의 양이 감소하는 것이 확인되었다. 감 과육의 경도는 방사선을 조사하지 않은 대조구에 비해 방사선 조사한 감과육의 경도가 감소하였다. 세포벽 성분의 변화는 알콜불용성 물질의 경우 대조구의 39.3 mg/g에 비해 방사선 처리의 경우 37.2 mg/g로 낮아졌다. 수용성 물질의 함량은 대조구의 경우 11.4 mg/g이었으나, 방사선 조사의 경우 13.9 mg/g로 높아졌으며, 세포벽 성분의 함량은 대조구의 경우 26.6 mg/g였으나, 방사선 조사의 경우 23.1 mg/g로 낮아져, 떫은감 과육이 방사선조사에 의해 숙성이 일어나 세포벽성분의 함량이 감소하고 수용성물질의 함량이 증가한 것으로 나타났다. 세포벽 구성다당류 중 lignin의 함량과 pectin질의 함량은 대조구의 0.82 mg/g, 3.56 mg/g에 비교해 방사선 조사의 경우 0.77 mg/g, 3.14 mg/g로 감소하였다. 산가용성 hemicellulose의 함량은 lignin과 pectin처럼 방사선 조사에 의해 감소하는 경향을 나타내었으나, 알칼리 가용성 hemicellulose와 cellulose는 방사선조사에 의해 증가하는 양상을 나타내었다. 감과육에 존재하는 세포벽 분해 및 연화효소인 polygalacturonase, pectinesterase와 β-galactosidase의 활성의 경우 방사선 조사에 의해 모든 효소활성이 증가하였다. 방사선 처리감의 관능검사 결과 수렴성은 대조구의 경우 매우 떫은 것으로 나타났으나 방사선처리 후에는 거의 떫지 않게 느껴졌고, 과육의 경도에 대한 관능검사 결과 대조구는 딱딱한 것으로 나타났으나 방사선처리 후에는 약간 물렁해 지는 것으로 나타나 방사선처리에 의해 탄닌의 중합이 일어나며 과육의 숙성도 동시에 발생하였다. 따라서 감마선 처리는 떫은 감의 수렴성 제거와 숙성 기간을 단축시킬 수 있는 새로운 방법으로 활용이 가능할 것으로 판단되었다.

The phenolic compounds which were extracted with 70% ethanol from Ulmus pumila for 12 hr were the highest as 17.9±1.0 mg/g. DPPH scavenging activity of 70% ethanol extracts was also the highest as 89.5±1.9% and it was confirmed to be high as 80% over in both of water and 70% ethanol extracts containing 50 μg/mL over phenolic concentration. ABTS radical cation decolorization activities of water and 70% ethanol extracts were higher as 96.8±2.9%, antioxidant protection factor (PF) was 2.0 PF in 70% ethanol and showed higher activities in both of water and 70% ethanol extracts containing 200 μg/mL phenolic concentration as 2.5 PF than BHA. TBARs of 70% ethanol extracts was 86.5±4.6%, it showed high anti-oxidative activity in 50∼200 μg/mL phenolic concentrations of water and 70% ethanol extracts as 80% over. The angiotensin converting enzyme (ACE) inhibitory activity of Ulmus pumila extracts against hypertension was 77.4% and 90.6% in water and 70% ethanol extracts of 200 μg/mL phenolic concentration. Xanthine oxidase inhibitory activity of Ulmus pumila extracts for anti-gout effect was not observed in water extracts, but it showed 30% inhibitory activity in 70% ethanol extracts, and 48.1% at 200 μg/mL phenolics concentration.

The effect of gamma irradiation on the storage stability of Undaria pinnatifida was investigated. A three-log reduction in total aerobic bacteria in U. pinnatifida samples was obtained by irradiation with 3 kGy. During storage for 2 weeks, the viable counts of microorganisms in non-irradiated U. pinnatifida increased to 6 log CFU/g. However, irradiation of U. pinnatifida by 5 kGy eliminated microorganisms. The Hunter of U. pinnatifida was slightly increased after 5 kGy of irradiation. The hardness properties of U. pinnatifida decreased during storage, but were not changed by irradiation with up to 3 kGy. These results indicate that low-dose irradiation (3 kGy) could be effective for improvement of the storage stability of U. pinnatifida.

수산 가공 부산물인 자숙액을 식품 및 공중보건 소재로 이용하기 위해 자숙액의 위생화를 위한 감마선 조사기술의 이용가능성을 검토하였다. 톳, 참치 및 굴 자숙액을 시료로 하여 1-5 kGy의 감마선을 조사하여 미생물 생존율을 측정하였고 생존미생물을 동정하였다. 굴 자숙액에서는 호기성 미생물이 검출되지 않았으나, 톳 및 참치 자숙액에서는 약 6.4 및 3.1 log CFU/g의 호기성 미생물이 검출되었고, 저장기간이 증가함에 따른 미생물 수에는 유의