본 연구는 표현 형질 생육 데이터인 엽장, 엽 수와 기상 데이 터인 생육도일을 활용하여 여러 기계 학습을 통해 마늘의 생 체중을 예측하는 모델을 개발하고자 하였다. 검증 데이터에 서 random forest 모델의 결정계수가 0.924, 평균제곱근오차 (g)는 13.583 그리고 평균절대오차는 8.885로 가장 우수하였 다. 평가 데이터에서는 Catboost 모델이 결정계수가 0.928, 평균제곱근오차(g)는 13.486 그리고 평균절대오차는 9.181 로 가장 우수하였다. 그러나 Catboost, Random forest 그리고 LightGBM 모델을 0.5, 0.3 그리고 0.2 가중치를 두어 학습한 Weighted ensemble 모델이 마늘 생체중 예측의 검증 및 평가 에 있어서 검증 데이터의 결정계수가 0.922, 평균제곱근오차 (g)가 13.752 그리고 평균절대오차는 8.877이었으며 평가 데 이터에서는 결정계수가 0.923, 평균제곱근오차(g)가 13.992 그리고 평균절대오차가 9.437로 두 번째로 우수한 결과를 나 타내었다. 이러한 결과들을 종합적으로 미루어 보았을 때, Weighted ensemble 모델이 모델의 안정성 측면에서 최적의 모델이라고 판단하였다. 따라서 농가들이 표현 형질과 기상 데이터만으로도 기계학습 기법을 통하여 마늘의 생체중 예측 을 통해 작형 모니터링이 가능할 것으로 보이며 추가적으로 다년도 데이터 취득과 검증을 통하여 성능을 고도화가 가능할 것으로 판단된다.
We previously reported that pyridoxine and its derivatives exert antidiabetic effects by alleviating postprandial hyperglycemia via inhibition of carbohydrate-hydrolyzing enzymes in normal sprague–dawley (SD) rats. In this study, we aimed to further evaluate whether long-term pyridoxal supplementation decreases the blood glucose levels using SD rats. SD rats were randomly assigned to groups fed a high-carbohydrate diet (66.1% cornstarch) with or without pyridoxal (4%) for 36 days. Changes in body weight, blood glucose levels, and food intake were measured daily for 36 days. Dietary supplementation with pyridoxal significantly decreased the blood glucose levels (P<0.001) and body weight (P<0.001) in mice. Glycated hemoglobin (HbA1c) levels, which are good indicators of plasma glucose concentrations over prolonged periods, were also significantly decreased over five weeks (P<0.001). Similarly, dietary treatment with Acarbose ® (0.04%), a positive control, also significantly decreased the blood glucose and HbA1c levels and body weight. Overall, our findings suggest that pyridoxal inhibits weight gain and alleviates postprandial hyperglycemia by decreasing glucose absorption and HbA1c levels.
목적 : 근시 교정용 비구면렌즈를 대상으로 중심 두께와 굴절률 및 굴절력 그리고 직경이 가장자리 두께와 무게에 어떠한 영향을 미치는지 비교하고 분석하고자 하였다. 방법 : 시중에 판매되고 있는 근시 교정용 렌즈를 굴절률(1.56~1.74)과 굴절력(-3.00~-8.00 D)별로 252개를 대상으로 선정하였다. 굴절률과 굴절력별로 40.00, 50.00 및 60.00 mm 직경 크기로 평산각 가공하여 가장자리 두께와 무게를 측정하여 그 결과를 비교 분석하였다. 결과 : 가장자리 두께는 직경이 1.00 mm 증가하였을 때 0.11 mm 증가하고 굴절력이 –1.00 D 증가하였을 때 0.50 mm 증가하며 굴절률이 한 단계 높아질 때 0.24 mm 감소한 것으로 나타났다. 무게는 직경이 1.00 mm 증가 하였을 때 0.42 g 증가하고 굴절력이 –1.00 D 증가하였을 때 0.75 g 증가하며 굴절률이 한 단계 높아질 때 0.08 g 감소한 것으로 나타났다. 가장자리 두께와 무게와의 인과관계는 직경이 가장 크고, 굴절력, 굴절률, 중심 두께 순으 로 나타났으며 가장자리 두께가 1.00 mm 증가하면 무게는 2.57 g 증가하는 것으로 나타났다. 결론 : 근시안을 비구면렌즈로 교정하고자 할 때, 굴절이상도와 안경렌즈 각 요소와의 관계를 고려하여 안경렌 즈를 선택하면 가장자리 두께 및 무게 감소에 도움이 되리라 사료된다.
Light-weight ceramic insulation materials and high-emissivity coatings were fabricated for reusable thermal protection systems (TPS). Alumina-silica fibers and boric acid were used to fabricate the insulation, which was heat treated at 1250 °C. High-emissivity coating of borosilicate glass modified with TaSi2, MoSi2, and SiB6 was applied via dip-and-spray coating methods and heat-treated at 1100°C. Testing in a high-velocity oxygen fuel environment at temperatures over 1100 °C for 120 seconds showed that the rigid structures withstood the flame robustly. The coating effectively infiltrated into the fibers, confirmed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction analyses. Although some oxidation of TaSi2 occurred, thereby increasing the Ta2O5 and SiO2 phases, no significant phase changes or performance degradation were observed. These results demonstrate the potential of these materials for reusable TPS applications in extreme thermal environments.
본 연구는 아메리카동애등에(Hermetia illucens)의 대량 사육을 위하여 남은음식물 사료의 최적 수분 함량과 적정 사육 밀도를 조사하였다. 실 험에서는 500 g의 습식 사료의 수분 함량을 각각 30%, 50%, 70%, 90%로 조정한 후, 3,500마리의 3령 유충을 7일 동안 사육하였다. 그 결과, 90% 수분 함량에서 평균 유충 무게는 7.19 g으로 측정되었고, 70% 수분 함량에서 가장 높은 무게인 10.54 g이 나타났다. 반면, 50%와 30% 수분 함량에 서는 유충 생육이 저조한 결과가 나타났다. 적절 사육 밀도를 조사를 위해 100,000, 150,000, 200,000, 250,000 마리의 3령 유충을 70% 수분함량 의 100 kg 습식 사료에 7일 동안 처리하였다. 그 결과, 250,000 마리에서 총 유충 생산량이 22.79 kg으로 가장 높게 나타났으나, 150,000, 200,000, 250,000 마리 밀도 간에는 유의미한 차이가 없었다. 100마리당 평균 무게는 100,000 마리에서 16.90 g, 150,000 마리에서 15.20 g, 200,000 마리 에서 11.30 g, 250,000 마리에서 9.50 g으로 확인되었으며, 100,000 마리와 150,000 마리 밀도 간에는 유의미한 차이가 없었다. 결론적으로, 남은 음식물 사료인 습식사료 100 kg를 급여할 경우 수분 함량을 70%로 유지하고 사육 밀도를 15만 마리로 설정하는 것이 가장 효과적임을 확인하였다.
To improve the lithium-ion battery performance and stability, a conducting polymer, which can simultaneously serve as both a conductive additive and a binder, is introduced into the anode. Water-soluble polyaniline:polystyrene sulfonate (PANI:PSS) can be successfully prepared through chemical oxidative polymerization, and their chemical/mechanical properties are adjusted by varying the molecular weight of PSS. As a conductive additive, the PANI with a conjugated double bond structure is introduced between active materials or between the active material and the current collector to provide fast and short electrical pathways. As a binder, the PSS prevents short circuits through strong π‒π stacking interaction with active material, and it exhibits superior adhesion to the current collector, thereby ensuring the maintenance of stable mechanical properties, even under high-speed charging/discharging conditions. Based on the synergistic effect of the intrinsic properties of PANI and PSS, it is confirmed that the anode with PANI:PSS introduced as a binder has about 1.8 times higher bonding strength (0.4 kgf/20 mm) compared to conventional binders. Moreover, since active materials can be additionally added in place of the generally added conductive additives, the total cell capacity increased by about 12.0%, and improved stability is shown with a capacity retention rate of 99.3% even after 200 cycles at a current rate of 0.2 C.
This study was conducted to investigate the proper design of alpha board used to support concrete blocks under high loads. A board height of 50 mm was appropriate to ensure a deflection of 3 mm or less under a load of 5 tons. The trapezoidal shape of the vibration absorbers in the interior of the board reduced the maximum deflection by evenly distributing the deflection across the board width. The height of the board is the most important variable in preventing deflection, and for the same board height, adjusting the thickness of the top and bottom plates was more effective in reducing the amount of deflection than adjusting the thickness of the stiffener. The theoretical solution is a good tool for easily predicting the deflection of the board, as it shows a difference of 5 to 15% from the simulation results. However, as a 2D prediction model, the theoretical solution cannot represent the distribution of deflection over the entire board area, so the 3D simulations are necessary in predicting the amount of deflection over the entire board.
Onboard truck scales can accurately measure payload under static conditions. However, their performance is limited in accounting for dynamic environments encountered during driving, leading to inaccuracies in load estimation under real-world conditions. This study employs TruckCaliber, a dynamic state measurement system, to estimate real-time vehicle loads. Fusion sensor modules were installed on leaf spring suspensions and vehicle frames to collect tilt and IMU data. The system was implemented on a commercial truck, and driving tests were conducted with varying payloads. The analysis focused on curved sections under different dynamic conditions.
This paper studied a new shape unit model based on Gibson and Ashby's theory. As a result of theoretical research, the relative density equation is correlated with relative elasticity, and through this study, the theoretical relationship between the relative elasticity equation was defined. The relative elasticity equation was defined based on the model for which the analysis was performed. According to the analysis results, the diameter of the model was set to 3 mm, and the maximum stress values were confirmed by reflecting the same boundary conditions. The maximum stress for each model is 5668.9MPa for Type 1, 5136.7MPa for Type 2, 5642MPa for Type 3, and 6032.9MPa for Type 4 when the truss diameter is 3mm. The relative elasticity equation was defined based on this condition. In the future, compression analysis will have to be performed in the same way, reflecting the diameter of the truss at 5 mm and 7 mm, to find and define the coefficients of the relative elasticity equation, and verification through experiments will have to be carried out based on the theoretical equation. In addition, in order to be applied in each field, proof through prototype production and installation must be carried out.
Recently, Car weight reduction has become an important development goal to improve fuel efficiency. Car seat frame is a key part of the weight reduction. Existing steel seat frames have the advantages of high rigidity and durability, but have the disadvantage of heavy weight. Recently, Almag material, which are alloy of aluminum and magnesium, is attracting attention because of excellence in strength and weight reduction. At first, the core stiffness members of the seat frame are selected to optimize the weight of the seat frame. And then strength analysis and natural frequency analysis are performed for the existing steel seat frame and Almag seat frame. Based on these analysis results, optimal thickness of the Almag seat frame are determined by an automation program using a genetic algorithm.
최근 국내외 화장품과 식품산업에서 다양하게 사용되어 지고 있는 콜라겐 단백질 제품은 점차 그 용도와 특성에 따라 보다 고도화, 기능화 되어 가고 있다. 피부 건강의 지표인 콜라겐은 다양한 용도로 개발되어 사용되고 있으 며, 콜라겐의 소비가 증가함에 따라 용도에 적합한 최적 화된 콜라겐 제품의 개발이 중요한 연구 분야이다. 특히 여러 기업과 연구기관들에 의해서 콜라겐의 흡수율을 높 이기 위한 다양한 노력이 이루어지고 있다. 따라서 본 연 구에서는 프란즈(Franz) 세포 시스템을 이용하여 국내에서 판매되는 다양한 분자량별 콜라겐 제품의 경피 및 구강 상피세포 투과성을 비교하였다. 그 결과, 피부 표피/진피 조직과 비교하여 구강점막 조직의 콜라겐 흡수율이 분자 량 500달톤과 1,000달톤의 경우 모두 통계적으로 유의하 게(각각 약 10배, 2배) 높은 것으로 확인되었다. 또한, 분 자량별 구강점막 조직 흡수율을 비교한 결과, 분자량 500 달톤의 콜라겐이 분자량 1,000달톤 제품에 비해 흡수율이 2-3배 증가함을 확인하였다. 분자량 500달톤의 경우 Cmax 와 AUCt 값이 가장 높게 나타났으며, 피부 표피/진피 세 포에 비해 구강점막세포 시험군의 모든 지표가 높은 것으 로 나타났다. 본 연구 결과는 피부 흡수보다는 구강 점막 세포를 통한 콜라겐의 흡수방법이 콜라겐 체내 흡수증가 에 유효한 수단임을 시사하며, 분자량 1,000달톤 이하에서 도 보다 더 작은 500달톤의 저분자 콜라겐의 흡수율이 증 가되는 것으로 보아 콜라겐의 분자량이 흡수율 증가의 주 요한 요소임을 확인할 수 있었다.
Background: This study focused on reproductive traits in Hanwoo cattle, specifically the environmental factors affecting gestation length and birth weight. Methods: The records of 1,540 cows calved at the Hanwoo Research Institute from 2015 to 2023 were examined. This study analyzed two populations, linebreeding Hanwoo (LBH) and general Hanwoo (GH), with all cows undergoing estrus synchronization and artificial insemination. The R software was used to compare the differences between the two populations and analyze the environmental factors affecting each trait. Results: The results showed that the average gestation length for LBH was 283.28 ± 5.93 days, which was significantly shorter than that of the GH, which had an average of 285.63 ± 6.21 days (p < 0.001). The average birth weight of LBH calves was 25.10 ± 3.69 kg, significantly lighter than GH calves, which weighed 27.26 ± 4.11 kg on average (p < 0.001). Analysis of environmental factors revealed significant differences in the gestation length of LBH based on dam parity, year, and season of calving. However, no significant differences were observed based on calf sex. For LBH, birth weight showed significant differences based on dam parity, year of calving, and sex of the calf, but not the season of calving. In GH, gestation length varied with dam parity and calving season, but not with calving year or calf sex. The GH birth weight showed differences based on dam parity, year of calving, and calf sex, but not the season of calving. Conclusions: Reproductive traits in the Hanwoo cattle industry are economically vital but are heavily influenced by environmental factors due to their low heritability. An accurate evaluation of the genetic potential of these traits requires an analysis of the environmental factors affecting them. The results of this study serve as foundational data for predicting the potential for genetic improvement in the gestation length and birth weight of Hanwoo cattle.
Zooplankton biomass is essential for understanding the quantitative structure of lake food webs and for the functional assessment of biotic interactions. In this study, we aimed to propose a biomass (dry weight) estimation method using the body length of cyclopoid copepods. These copepods play an important role as omnivores in lake zooplankton communities and contribute significantly to biomass. We validated several previously proposed estimation equations against direct measurements and compared the suitability of prosomal length versus total length of copepods to suggest a more appropriate estimation equation. After comparing the regression analysis results of various candidate equations with the actual values measured on a microbalance-using the coefficient of variation, mean absolute error, and coefficient of determination-it was determined that the Total Length-DW exponential regression equation [W=0.7775×e2.0183L; W (μg), L (mm)] could be used to calculate biomass with higher accuracy. However, considering practical issues such as the morphological similarity between species and genera of copepods and the limitations of classifying copepodid stages, we derived a general regression equation for the pooled copepod community rather than a species-specific regression equation.
Obesity occurs when the body consumes more energy than it requires and uses less energy, resulting in the accumulation of fat, which increases the number and size of fat cells in the body. It causes high blood pressure, type 2 diabetes, and joint crowding, making it difficult to fully treat. We investigated the effects of chito oligosaccharide(CHO) functional material, which suppresses fat accumulation, restores dyslipidemia values, and has no side effects.In this study, we investigated the ameliorative effects of CHO on obese mice fed a high-fat diet. The experimental groups were divided into 5 groups (n=10) of C57BL/6 mice: normal control (N), control group (C), and chito oligosaccharide low concentration (L), medium concentration (M), and high concentration (H) groups. We tested whether CHO has an effect on obesity through body weight and adipose tissue weighing, serum lipid testing, and histological examination. Experimental analysis showed that CHO reduced body weight and adipose tissue weight, improved the concentrations of TCHO, TG, HDL, and LDL, which are factors for dyslipidemia diagnosis, and decreased the diameter size of adipose tissue. These results suggest that CHO alleviates the levels of fat growth inhibition and dyslipidemia levels in obese-induced mice, and has a positive effect on obesity.
In this study, we examined the assembly and components of a 40-feet container chassis based on its 3D shape. Utilizing the finite element method, we conducted structural analysis considering the total weight, including the 40-ton weight specified in automotive regulations, along with a safety margin of 1.5 under extreme load conditions. And also fixed and junction conditions were applied to the chassis system. Subsequently, we presented the maximum stress results derived from the structural analysis of both the overall chassis system and its individual components. Finally, we evaluated the structural stability of the 40-feet container chassis by comparing and reviewing the maximum stress with the yield strength of the material used for each component.
기체 분리막의 상업적 발전은 CO2 분리 효율을 향상시키는 데 중요한 역할을 한다. 고분자량 PEO (high-Mw PEO)는 높은 CO2 용해도, 가격 경쟁성 및 견고한 기계적 특성을 가져 분리막 제조용 고분자로 유력하지만 그 특유의 결정성 으로 인해 기체 분리막에 응용이 어렵다. 본 연구에서는 결정성 감소를 위해 다양한 고분자 첨가제를 고분자량 PEO에 혼합 하는 방법을 제시하였다. 폴리에틸렌글리콜(PEG), 폴리프로필렌글리콜(PPG), 폴리아크릴산(PAA) 및 폴리비닐피롤리돈(PVP) 과 같은 상업적으로 이용 가능하고 섞임성이 좋은 수용성 고분자를 첨가제로 사용하여 PEO 결정성을 감소시킴으로써 가스 분리 성능을 향상시키고자 하였다. PEG 및 PPG의 경우 PEO의 결정 구조를 억제하지 못하고 분리막의 결함을 초래하였으나, PAA 및 PVP는 PEO의 결정 구조를 바꿔 결함이 없는 분리막을 제조하는 데 성공하였다. 고분자량 PEO 혼합막의 결정 구조 변화와 기체 분리 성능의 상관관계를 조사하여 본 연구의 결과와 이전에 기록된 결과를 바탕으로 고분자량 PEO에 대한 첨가 제 고분자의 설계 및 선택에 대한 통찰력을 제공하며, 이를 통해 비용 효율적이고 상업적으로 실용적인 CO2 분리막을 제조하 고자 하였다.