This study analyzes the seismic response of traffic light poles, considering soil-foundation effects through nonlinear static and time history analyses. Two poles are investigated, uni-directional and bi-directional, each with 9 m mast arms. Finite element models incorporate the poles, soil, and concrete foundations for analysis. Results show that the initial stiffness of the traffic light poles decreases by approximately 38% due to soil effects, and the drift ratio at which their nonlinear behavior occurs is 77% of scenarios without considering soil effects. The maximum acceleration response increases by about 82% for uni-directional poles and 73% for bi-directional poles, while displacement response increases by approximately 10% for uni-directional and 16% for bi-directional poles when considering soil-foundation effects. Additionally, increasing ground motion intensity reduces soil restraints, making significant rotational displacement the dominant response mechanism over flexural displacement for the traffic light poles. These findings underscore the importance of considering soil-foundation interactions in analyzing the seismic behavior of traffic light poles and provide valuable insights to enhance their seismic resilience and safety.

Recently, in the case of the root industry, although it is a basic industry that forms the basis of manufacturing competitiveness, there continues to be a shortage of manpower due to reasons such as dangerous working environments, industrial economic difficulties, and low wage systems. In addition, the demand for automation of production lines using robots is increasing due to a shrinking labor market due to a decrease in the working population due to aging, higher wages, shorter working hours, and limitations of foreign workers. In this study, a system was developed to automate the injection molding process for producing ball valves for automobiles by applying robot system. The applied process flow consists of alignment and insertion of insert parts, and removal, transfer, and loading of the product after injection molding, which is currently performed manually. Through the application of the developed robot automation system, the cycle time was improved by more than 30% and the defect rate was reduced by more than 70%.

This study used optical and scanning electron microscopy to analyze the surface oxidation phenomenon that accompanies a γ'-precipitate free zone in a directional solidified CM247LC high temperature creep specimen. Surface oxidation occurs on nickel-based superalloy gas turbine blades due to high temperature during use. Among the superalloy components, Al and Cr are greatly affected by diffusion and movement, and Al is a major component of the surface oxidation products. This out-diffusion of Al was accompanied by γ' (Ni3Al) deficiency in the matrix, and formed a γ'-precipitate free zone at the boundary of the surface oxide layer. Among the components of CM247LC, Cr and Al related to surface oxidation consist of 8 % and 5.6 %, respectively. When Al, the main component of the γ' precipitation phase, diffused out to the surface, a high content of Cr was observed in these PFZs. This is because the PFZ is made of a high Cr γ phase. Surface oxidation of DS CM247LC was observed in high temperature creep specimens, and γ'-rafting occurred due to stress applied to the creep specimens. However, the stress states applied to the grip and gauge length of the creep specimen were different, and accordingly, different γ'-rafting patterns were observed. Such surface oxidation and PFZ and γ'-rafting are shown to affect CM247LC creep lifetime. Mapping the microstructure and composition of major components such as Al and Cr and their role in surface oxidation, revealed in this study, will be utilized in the development of alloys to improve creep life.

아미노글리코사이드계 항생제(Aminoglycosides, AGs) 는 그람음성균과 양성균에 광범위하게 작용하는 동물용 의약품으로, 최근 배양육에 사용된다고 알려져 있어, 안 전성 관리를 위한 분석법 마련이 반드시 필요하다. AGs 는 고극성 화합물로 성분 간의 분리를 위해 이온쌍 시 약(ion-pairing reagent, IPR)을 사용하고 있으나 IPR을 이동상에 첨가하는 기존 분석방법의 경우 용매가 흐르 는 동안 질량분석기로 주입되는 IPR로 인해 기기적인 문 제가 발생할 가능성이 높아, IPR를 바이알에 직접 첨가 하는 분석방법을 검토하였다. 본 연구에서 10종 AGs 성 분에 대한 분석방법을 확인하고 유효성을 검증하였다. 검출한계와 정량한계는 각각 0.0001-0.0038 mg/kg 와 0.004-0.011 mg/kg의 범위로 나타났으며, 0.01-0.5 mg/ kg 범위 내의 직선성(R2)은 0.99 이상이었다. AGs의 시 료 회수율을 확인하고자 소고기와 세포배양배지(cell culture medium) 매질에서 회수율과 상대표준편차로 나 타낸 정밀도를 확인한 결과 각각 70.7-120.6% 및 0.2 to 24.7%로 나타났다. 기존의 이동상에 IP 첨가 방법과 비 교하였을 때 유사한 수준으로 양호하였다. 검증된 AGs 분석법은 국내 유통되는 닭고기, 소고기, 돼지고기 15품 목과 배양육 배지 첨가제 6품목에 적용해보았다. 그 결 과 국내 유통되는 육류 15품목 모두 AGs 성분이 검출 되지 않았으나, 세포배양배지에서 streptomycin은 695.85- 1152.71 mg/kg, dehydrostreptomyci은 6.35-11.11 mg/kg 로 검출되었다. 따라서 IRR을 바이알에 직접 첨가하는 LC-MS/MS 방식은 육류, 세포배양배지, 배지첨가제 중 AGs 분석 및 안전성 평가를 위한 기초자료로 활용될 것 으로 기대된다.

Fouling is an inevitable problem in membrane water treatment plant. It can be measured by trans-membrane pressure (TMP) in the constant flux operation, and chemical cleaning is carried out when TMP reaches a critical value. An early fouilng alarm is defined as warning the critical TMP value appearance in advance. The alarming method was developed using one of machine learning algorithms, decision tree, and applied to a ceramic microfiltration (MF) pilot plant. First, the decision tree model that classifies the normal/abnormal state of the filtration cycle of the ceramic MF pilot plant was developed and it was then used to make the early fouling alarm method. The accuracy of the classification model was up to 96.2% and the time for the early warning was when abnormal cycles occurred three times in a row. The early fouling alram can expect reaching a limit TMP in advance (e.g., 15-174 hours). By adopting TMP increasing rate and backwash efficiency as machine learning variables, the model accuracy and the reliability of the early fouling alarm method were increased, respectively.

Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer, and it has been steadily increasing in worldwide. Pituitary tumor transforming gene 1 (PTTG1) has been known as oncogene in a verity of cancers. Nevertheless, the expression and role of PTTG1 in OSCC progression remains largely unexplored. In this study, clinical datasets were analyzed to assess the genetic impact of PTTG1 on OSCC progression and to identify its functional roles in OSCC cell lines. We analyzed the expression of PTTG1 in head and neck squamous cell carcinoma (HNSC) and OSCC using databases form the Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). To investigate the effect of PTTG1 on proliferation and migration abilities in OSCC cell lines, following the knockdown of PTTG1 in HSC-2 and SCC-9 cell lines, we analyzed the proliferation and metastatic abilities of OSCC cells using EdU and Boyden chamber assays. Our database analysis revealed that PTTG1 was significantly overexpressed in tumor tissues compared to normal tissues. Moreover, its expression correlated with clinical parameters of OSCC. In vitro experiments demonstrated that depletion of PTTG1 suppressed the ability of cell proliferation and migration in both HSC-2 and SCC-9 cell lines. In conclusion, our study suggests that PTTG1 may act as an oncogene in OSCC. These findings provide new insights into the mechanisms and clinical implications of PTTG1 expression in OSCC patients.

국제적인 선박 배출 가스에 대한 환경 규제가 점차 강화됨에 따라 전기추진 및 하이브리드 추진선박에 대한 관심이 증대되고 있으며, 이러한 선박에 적용하기 위한 다양한 솔루션이 개발 및 적용되고 있는데 특히 전력계통의 안정화, 시스템의 효율성을 높이기 위 한 방안으로 직류배전시스템이 적용되고 있다. 또한, 선박용 직류배전시스템에 대한 안전 및 성능에 대한 검증 및 시험의 중요성이 요구 되고 있다. 본 연구는 직류배전 테스트베드 구축 및 직류배전(가변속 발전)시스템에 대한 성능을 검증하고 연료소모량 분석한 결과로서 선박용 직류배전에 적용되고 있는 가변속 발전시스템을 적용하였으며, 발전기에서 출력되는 전력을 정류기를 통해 직류전력으로 변환하 여 시스템에 연계하고 이러한 장치들을 감시 및 제어하기 위한 시스템을 개발하였다. 이러한 직류배전 시스템을 적용한 시험을 통해 최 대 전압은 751.5V이고 최소전압은 731.4V가 계측되어 전압변동률은 2.7%로 3% 이내에서 안정적으로 전압이 공급되는 것을 확인하였고 부 하변동에 따라 가변속 발전시스템을 적용하였을 경우 연료소모량이 기존 정속발전시스템과 비교하여 구간에 따라 최대 20%이상 연료절 감이 되는 것을 시험을 통해 확인하였다.

선박 발전기의 여자기는 출력 단자 전압을 일정하게 유지하기 위하여 여자전류 제어를 통해 자속을 조정한다. 여자기 내부에 있는 전압제어기는 통상적으로 비례 적분 제어방식이 사용되는데 게인과 시정수에 의해 결정되는 응답 특성은 적절치 못한 설정값에 의 해 원하지 않는 출력을 내며 이로 인해 선내 전력의 품질과 안정성을 떨어뜨릴 수 있다. 본 논문에서는 IEEE에서 제공하는 AC4A 타입의 여자기 모델을 통해 얻을 수 있는 안정적인 입출력 데이터를 활용하여 신경망 회로를 학습시킨 후 기존의 비례 적분 제어방식의 전압제 어기를 학습된 신경망 회로 제어기로 대체하여 시뮬레이션을 수행하였다. 그 결과 기존 대비 최대 9.63%까지 오버슈팅이 개선되었으며, 안정적인 응답 특성에 대한 우수성을 확인하였다.

On pig farms, the highest mortality rate is observed among nursing piglets. To reduce this mortality rate, farmers need to carefully observe the piglets to prevent accidents such as being crushed and to maintain a proper body temperature. However, observing a large number of pigs individually can be challenging for farmers. Therefore, our aim was to detect the behavior of piglets and sows in real-time using deep learning models, such as YOLOv4-CSP and YOLOv7-E6E, that allow for real-time object detection. YOLOv4-CSP reduces computational cost by partitioning feature maps and utilizing Cross-stage Hierarchy to remove redundant gradient calculation. YOLOv7-E6E analyzes and controls gradient paths such that the weights of each layer learn diverse features. We detected standing, sitting, and lying behaviors in sows and lactating and starving behaviors in piglets, which indicate nursing behavior and movement to colder areas away from the group. We optimized the model parameters for the best object detection and improved reliability by acquiring data through experts. We conducted object detection for the five different behaviors. The YOLOv4-CSP model achieved an accuracy of 0.63 and mAP of 0.662, whereas the YOLOv7-E6E model showed an accuracy of 0.65 and mAP of 0.637. Therefore, based on mAP, which includes both class and localization performance, YOLOv4-CSP showed the superior performance. Such research is anticipated to be effectively utilized for the behavioral analysis of fattening pigs and in preventing piglet crushing in the future.

효율적인 산림관리와 경영이 이루어지기 위해서는 일정한 공간단위를 가지는 산림의 구획(Zoning)이 정의되어야 한다. 현재 국유림은 임･소반 기준으로, 공･사유림은 필지 단위를 기준으로 공간을 구획하여 활용하고 있다. 이러한 이원적인 공간구획체 계는 통일된 산림계획, 경영, 관리가 어려우며 장기적인 공간단위의 정보 구축과 생성, 관리에도 어려움을 끼칠 수 있다. 이에, 본 연구에서는 DEM(Digital Elevation Model) 기반으로 추출한 산줄기 유역을 소개하고 활용성 검토를 위해 현재 산림관리 단위인 임･소반도, 경영계획구, 산지/산림 관련 주제도와 중첩 분석을 수행하였다. 이를 통해 표준산림관리단위의 대안으로 제안한 각 규모별 산림유역 단위의 공간적 적합성을 검토하고 산림관리, 산림 디지털 공간자료 구축 및 관리 등의 분야에서 산줄기 내포 유역 기반 표준산림관리단위의 활용 방안을 제안하였다.

오대산국립공원의 고등균류 다양성 및 분포 특성을 시기별, 고도별, 임상별로 조사하여 비교하였다. 오대산국립공원 내 계방산, 소금강, 월정사지 구 일대에 임상별 6개씩 총 18개의 고정조사구에서 고등균류를 채집한 결과, 542점의 표본을 채집하였으며, 동정한 결과 81속, 256종으로 확인되었 고 최신분류체계로 분류한 결과 2문, 6강, 19목, 56과로 확인되었다. 부생성 균류가 62.9 %로 가장 높은 비율을 보였으며, 다음으로는 공생성 균류 36.2 % 기생성 균류 0.9 % 순으로 조사되었고, 우점종은 맑은애주름버섯(Mycena pura)과 굽은꽃애기버섯(Gymnopus dryophilus)으로 확인되었다. 해발고도에 따른 고등균류의 분포는 200∼677 m 조사구에서 109종, 700∼999 m에서 109종, 1000∼1400 m에서 118종이 조사되었 으며, 채집 시기별 고등균류의 분포는 9월에 132종으로 가장 많이 조사되었고, 6월 33종, 7월 75종, 8월 99종으로 조사되었다. 임상별로는 혼효림에서 124종, 활엽수림 121종, 침엽수림에서 가장 낮은 105종이 조사되었다. 고도별, 시기별, 임상별 모두 부생성 균류가 가장 높은 비율로 분포하였다. 종다양도는 9월에 2.00, 혼효림에서 2.04로 가장 높았고, 고도별로는 유사한 종다양도를 나타냈다(1.93∼1.99). 종 균등도는 고도별, 시기별, 임상별로 비슷한 수준을 나타냈다(0.94∼0.97). 공통 발생 종은 모든 시기에 2종, 전체 고도에서 7종, 침엽수, 활엽수, 혼효림에서 14종이 확인되었다.

The aim of this study was to compare the antioxidant activities and functional contents of Korean conventional and Chinese seed gingers from the Jeollabuk-do Wanju and Chungcheongnam-do Seosan regions. Ginger samples were subjected to steaming treatments for different durations (2–8 h) at 121oC using an autoclave. The antioxidant activity was evaluated by measuring total polyphenol and flavonoid contents and ABTS and DPPH radical scavenging activities, while functional ingredient contents were analyzed for gingerols and shogaols. The results showed that Wanju conventional seed ginger (WO-2) had the highest total polyphenol (85.24 mg GAE/g) and flavonoid (98.14 RE/100 g) contents, surpassing that of the control in all steamed groups at 6 h. ABTS radical scavenging activity showed a strong correlation with total polyphenol and flavonoid contents. The control groups indicated that Korean conventional seed ginger had 1.0–1.3 times higher gingerol contents compared to Chinese seed ginger. Furthermore, the content of shogaols, considered major functional ingredients, increased significantly with longer steaming durations, reaching the highest content (1,793 mg/kg) at 8 h, which was 1.0–1.8 times higher in Korean conventional seed ginger than that in Chinese seed ginger. These experiments provide valuable data supporting the excellence of Korean conventional seed ginger in the future.

Porous ceramics are used in various industrial applications based on their physical properties, including isolation, storage, and thermal barrier properties. However, traditional manufacturing environments require additional steps to control artificial pores and limit deformities, because they rely on limited molding methods. To overcome this drawback, many studies have recently focused on fabricating porous structures using additive manufacturing techniques. In particular, the binder jet technology enables high porosity and various types of designs, and avoids the limitations of existing manufacturing processes. In this study, we investigated process optimization for manufacturing porous ceramic filters using the binder jet technology. In binder jet technology, the flowability of the powder used as the base material is an important factor, as well as compatibility with the binder in the process and for the final print. Flow agents and secondary binders were used to optimize the flowability and compatibility of the powders. In addition, the effects of the amount of added glass frit, and changes in sintering temperature on the microstructure, porosity and mechanical properties of the final printed product were investigated.

The Ag/WC electrical contacts were prepared via powder metallurgy using 60 wt% Ag, 40 wt% WC, and small amounts of Co3O4 with varying WC particle sizes. After the fabrication of the contact materials, microstructure observations confirmed that WC-1 had an average grain size (AGS) of 0.27 μm, and WC-2 had an AGS of 0.35 μm. The Ag matrix in WC-1 formed fine grains, whereas a significantly larger and continuous growth of the Ag matrix was observed in WC-2. This indicates the different flow behaviors of liquid Ag during the sintering process owing to the different WC sizes. The electrical conductivities of WC-1 and WC-2 were 47.8% and 60.4%, respectively, and had a significant influence on the Ag matrix. In particular, WC-2 exhibited extremely high electrical conductivity owing to its large and continuous Ag-grain matrix. The yield strengths of WC-1 and WC-2 after compression tests were 349.9 MPa and 280.7 MPa, respectively. The high yield strength of WC-1 can be attributed to the Hall–Petch effect, whereas the low yield strength of WC-2 can be explained by the high fraction of high-angle boundaries (HAB) between the WC grains. Furthermore, the relationships between the microstructure, electrical/mechanical properties, and deformation mechanisms were evaluated.

FT-IR, GC/MS, and ATR-FT-IR analyses were performed to confirm the physicochemical characteristics of saw palmetto fruit (SPF) extract. FT-IR analysis of the standard product showed that the band corresponding to the carbonyl bond of free fatty acid was stronger than the band of acyl-glyceride. Sample E was identified as having the same trend as the standard sample. Fatty acid composition analysis revealed that the main fatty acids in the standard sample were lauric acid and oleic acid. The content of lauric acid ranged from approximately 30% to 38% in samples B, C, D, and E, while the content of oleic acid ranged from approximately 29% to 34%. The GC/MS analysis confirmed that the standard SPF extract consisted of fatty acids and fatty acid ethyl esters. Sample E demonstrated a similar pattern to the standard samples in terms of oleic acid, lauric acid, and fatty acid esters. ATR-FT-IR analysis indicated that only sample E was predicted to contain 100% saw palmetto extract. Therefore, these study findings can be considered fundamental data for analyzing the physicochemical characteristics of the composition of SPF extract.