This paper addresses a scheduling problem aimed at minimizing makespan in a permutation flow shop with two machines and an inspection process that must be conducted at least once every certain number of outcomes from the first machine. A mathematical programming approach and a genetic algorithm, incorporating Johnson's rule and a specific mutation process, were developed to solve this problem. Johnson's rule was used to generate an initial population, while the mutation process ensured compliance with the inspection constraints. The results showed that within a computation time limit of 300 seconds, the mathematical programming approach often failed to provide optimal or feasible solutions, especially for larger job sets. For instance, when the process times of both machines were similar and the inspection time was longer, the mathematical programming approach failed to solve all 10 experiments with just 15 jobs and only had a 50% success rate for 100 jobs. In contrast, the proposed genetic algorithm solved all instances and delivered equal or superior results compared to the mathematical programming approach.
Lumpy Skin Disease (LSD) and Foot-and-Mouth Disease (FMD) cause substantial economic losses on the livestock industry. Therefore, vaccinations have been implemented as the control strategy in endemic countries. However, the potential adverse effects of administering vaccines for both diseases simultaneously have not been thoroughly evaluated. The aim of this study was to assess the impact of vaccinating dairy cows with either or both LSD and FMD vaccines on milk production and physiological parameters such as milk temperature, rumination time and body weight. The experimental groups were divided into four according to the injection materials: 1) saline, 2) LSD vaccine, 3) FMD vaccine, and 4) both vaccines. The impact of vaccination on milk yield and physiological parameters was evaluated daily until 12 days post-vaccination, and milk components were analyzed twice, once per week. Among the experimental groups as well as each vaccine group, no statistically significant differences (p < 0.05) were observed at milk yield, milk components, or milk temperature. This suggests that simultaneous vaccination of LSD and FMD can be administered without adverse effects.
이 연구는 다목적 선박(MPV)의 공기역학적 구조물 설계, 분석 및 향상을 통해 그린 워터 압력에 의한 구조적 안전을 보장하고, 탈탄소화 및 에너지 효율성에 이바지하는 방법을 기술하였다. 유한 요소 분석(FEA)을 통한 초기 평가에서 좌굴 발생에 대한 잠재적인 취약점 이 있음을 확인하였다. 이러한 문제를 해결하기 위해 보강재(Carling stiffener)와 두께 증가를 통하여 응력을 재분배하고 국부적인 좌굴 발생의 위험을 최소화하였다. 보강 후 분석 결과, 한국선급(KR)의 안전 기준인 항복 강도, 미국 선급(ABS) 좌굴 강도 및 노르웨이 표준(NORSOK) 변 위 기준을 모두 충족하는 것이 확인되었다. 결과적으로 고유치 좌굴 해석 결과가 안전 기준을 초과하고 최대 변위가 허용 한계 내에 있는 등 중요한 개선이 이루어졌다. 이러한 개선은 극한의 해양 조건에서 운영 신뢰성을 보장할 수 있다. 이 연구는 공기역학적 항력 감소와 구조적 안전성의 이중적인 이점을 강조하며, 국제 해사 기구(IMO)의 2050 탈탄소화 목표에 부합하는 연료 효율성 및 온실가스 배출 감소에 이바지할 수 있다. 연구 결과는 다양한 선박 유형에 걸쳐 항력 감소 기술을 확장하기 위한 기초 자료를 제공하며, 지속 가능하고 탄력적인 해양 운영을 위한 대안을 제시하였다. 향후 연구는 구조적 안전 평가를 가속할 수 있는 단순화된 모델링 기술 개발에 집중할 것이다.
Current investigations provide a comprehensive understanding of the occurrence and biodiversity of plant-parasitic nematodes (PPNs) in the major citrusproducing regions of Jeju Island, South Korea. Our survey identified five genera and five species of PPNs from 82 infested Citrus unshiu field samples collected across 116 sites in the Jeju provinces. Community analysis revealed the highest prevalence of PPNs (39.02%) at Namwon-eup, significantly driven by Tylenchulus semipenetrans, followed by Paratylenchus sp., Helicotylenchus sp., Meloidogyne sp., and Pratylenchus sp. Data indicate that all 82 sites were infested with T. semipenetrans (70.68%), marking a considerable increase in prevalence compared to previous surveys and posing a significant threat to citrus cultivation. The study results also demonstrate the influence of soil type on PPNs communities, revealing correlations between soil texture and nematode diversity. Citrus orchards cultivated in black clay loam soil exhibited significant PPN infestations. Overall, the PPN survey underscores the economic importance of monitoring citrus nematode infection rates and maintaining economic threshold levels in citrus production. It also emphasizes the need for developing effective management strategies to control PPNs, which are essential for maintaining crop yield and ensuring agricultural sustainability.
In this work, the depth of the interphase in graphene polymer systems is determined by the properties of graphene and interfacial parameters. Furthermore, the actual volume fraction and percolation onset of the nanosheets are characterized by the actual inverse aspect ratio, interphase depth, and tunneling distance. In addition, the dimensions of graphene, along with interfacial/interphase properties and tunneling characteristics, are utilized to develop the power-law equation for the conductivity of graphene-filled composites. Using the derived equations, the interphase depth, percolation onset, and nanocomposite conductivity are graphed against various ranges of the aforementioned factors. Moreover, numerous experimental data points for percolation onset and conductivity are presented to validate the equations. The optimal levels for interphase depth, percolation onset, and conductivity are achieved through high interfacial conductivity and large graphene nanosheets. In addition, increased nanocomposite conductivity can be attained with thinner nanosheets, a larger tunneling distance, and a thicker interphase. The calculations highlight the considerable impacts of interfacial/interphase factors and tunneling distance on the percolation onset. The highest nanocomposite conductivity of 0.008 S/m is acquired by the highest interfacial conduction of 900 S/m and graphene length (D) of 5 μm, while an insulated sample is observed at D < 1.2 μm. Therefore, higher interfacial conduction and larger nanosheets cause the higher nanocomposite conductivity, but the short nanosheets cannot promote the conductivity.
The AlSi10Mg alloy has garnered significant attention for its application in laser powder bed fusion (L-PBF), due to its lightweight properties and good printability using L-PBF. However, the low production speed of the L-PBF process is the main bottleneck in the industrial commercialization of L-PBF AlSi10Mg alloy parts. Furthermore, while L-PBF AlSi10Mg alloy exhibits excellent mechanical properties, the properties are often over-specified compared to the target properties of parts traditionally fabricated by casting. To accelerate production speed in L-PBF, this study investigated the effects of process parameters on the build rate and mechanical properties of the AlSi10Mg alloy. Guidelines are proposed for high-speed additive manufacturing of the AlSi10Mg alloy for use in automotive parts. The results show a significant increase in the build rate, exceeding the conventional build rate by a factor of 3.6 times or more, while the L-PBF AlSi10Mg alloy met the specifications for automotive prototype parts. This strategy can be expected to offer significant cost advantages while maintaining acceptable mechanical properties of topology-optimized parts used in the automobile industry.
The alfalfa weevil (Hypera postica) is an important pest that causes significant damages to alfalfa crops, reducing yield and quality, but there’s a solution. This research had two main goals to evaluate the efficacy of insecticides available in Korea for alfalfa weevil control and to provide data for pest management studies. The experiment, conducted from 2023 to 2024 at the National Institute of Animal Science in Cheonan, Republic of Korea, included four treatment plots: control (CON), early-occurrence (EAR), mid-occurrence (MID), and late-occurrence (LAT). It also included two frequency plots with primary and secondary insecticide using 50% fenitrothion emulsion, which made it truly comprehensive study. The primary insecticide was applied at the first observation of the alfalfa weevil larvae, with subsequent secondary applications at specified intervals. The results showed that two-times insecticide applications significantly reduced larvae populations and increased yield and nutrient content compared to a single application. Specifically, control rates ranged from 94 to 94.7% on the third day after treatment and from 72.2 to 93.4% on the seventh day. Plots with two applications had higher yields and crude protein content. The study concluded that the timing and frequency of insecticide applications are critical to maximizing alfalfa yield and quality, emphasizing the importance of optimized application strategies for effective pest control.
Considering the various health problems associated with obesity in dogs, including renal diseases, joint disorders, and skin diseases, effective management strategies and guidelines are urgently needed. This situation has led to a growing demand for veterinary medications aimed at addressing obesity in dogs. However, the field faces a significant hurdle due to the absence of standardized guidelines for assessing the effectiveness of these anti-obesity medications in dogs. In response to this gap, the Animal and Plant Quarantine Agency (APQA) in Korea has made a crucial step by introducing clinical trial guidelines to evaluate the efficacy of treatments for canine obesity, specifically aimed at approving veterinary medicinal products. The guidelines outlined the selection criteria for target dogs, highlighting the importance of consistency within the control and treated groups. Treatment efficacy is subsequently evaluated by physical examination, body fat reduction, and biochemical indicators. In addition, the guidelines cover dosage and administration, monitoring after dosing, and statistical analysis. By doing so, this guideline not only highlights the significance of the APQA’s initiative in improving the care of obese dogs but also provides practical insights to enhance the standardization and effectiveness of clinical trials in veterinary medicine.
This study evaluated the immunogenicity of the Bacillus Calmette-Guérin (BCG) vaccine in a guinea pig model to refine preclinical assessment methods. 24 guinea pigs were divided into four groups for immunohistochemical, histopathological, and molecular analyses, including qRT-PCR and ELISA. The ELISA results revealed significant elevations in interleukin 2 (IL-2), interferon-gamma (IFN- ), and tuberculosis-specific antibodies in vaccinated guinea pigs, particularly γ notable after 6 weeks. Although lung cytokine levels remained unchanged, spleen gene expression showed significant differences in interleukin-17, interleukin-12, interleukin-1β, and C-X-C motif chemokine ligand 10 after 6 weeks. Immunohistochemistry revealed peak IL-2 expression at 8 weeks and significant IFN-γ and TNF-α expression at 6 weeks. This study confirmed the effectiveness of BCG vaccine in guinea pigs, providing crucial insights for future tuberculosis vaccine development and standardizing immune response indicators.
가는납작벌레과의 미기록종인 Ahasverus advena (Waltl) (곡식가는납작벌레, 신칭), Psammoecus trimaculatus Motschulsky (닮은모래가 는납작벌레, 신칭)을 한국에서 처음으로 보고한다. 각 종에 대한 외형과 진단형질, 분포지도를 제공한다.
This study aims to contribute to resolving the critical issue of weed management in newly established alfalfa fields, study has been conducted on effective herbicide use. The study evaluated the impact of various domestically available foliar herbicides on alfalfa phytotoxicity, weed control, yield, and nutritive value. The experiment was designed in a randomized complete block design with four treatments. Alfalfa ‘SW 5615’ seeded in the spring of 2024 on a 1 ha field (March 18), with herbicide treatments including fluazifop-P-butyl (FPB), bentazone (BEN), and a mixture of these herbicides (MIX). Herbicide efficacy, alfalfa yield, and nutritive value were assessed 30 days post-application. Results indicated that the MIX treatment achieved superior weed control comparable to hand weeding (HW), although it exhibited higher phytotoxicity, requiring extended recovery periods. While MIX led to lower overall yield, it enhanced alfalfa purity, resulting in higher crude protein (CP) content and relative feed value (RFV) compared to other treatments. The study concludes that despite the potential for increased phytotoxicity, mixed herbicide treatments could offer a strategic advantage in enhancing the quality of alfalfa feed through effective weed management, thereby improving CP and RFV, critical factors for the nutritional value of alfalfa. These findings provide valuable insights for optimizing weed management practices in alfalfa cultivation, suggesting that mixed herbicide application, although associated with increased phytotoxicity on the plants, could improve the overall feed quality by reducing weed competition.