Vertical takeoff and landing (VTOL) drones are increasingly recognized as an important solution for last-mile delivery in the food and beverage sector, owing to their rapid deployment capabilities and high operational flexibility. In particular, growing interest in drone delivery services has been observed among fast food and coffee franchises, where rapid delivery is essential due to the time-sensitive nature of food and beverage items intended for immediate consumption. Despite this trend, there remains a lack of research on the structural modeling of flight routes for VTOL drones operating under automatic flight conditions, and on the implementation of first-come-first-served (FCFS) delivery services utilizing predefined flight routes. Accordingly, this study comprehensively describes the operations for food and beverage delivery services using VTOL drones. In particular, it addressed the use of multiple drones to conduct FCFS-type multi-point delivery services along fixed routes suitable for automatic flight.

오늘날 대학 교양교육은 학습자의 다양한 강점과 개별성을 존중하며 균형 잡힌 성장과 융복합 역량의 함양을 지향하고 있다. 그러나 이러한 목표를 효과적으로 뒷받침할 수 있는 교수·학습 방법과 평가 방식의 실 제 적용에는 여전히 현실적인 제약이 존재한다. 이에 본 연구는 하워드 가드너(Howard Gardner)의 다중지능 이론을 대학 교양교육에 적용하여 학습자의 고유성과 창의성, 집단지성을 발현하게 하는 교육적 가능성과 주요 과제를 탐색하였다. 연구 결과, 다중지능 이론(Multiple Intelligences Theory, MI)은 인간 능력의 다양성과 전인적 발달을 강조하며 제너럴리 스트(generalist) 소양의 함양이라는 대학 교양교육의 방향성에 부합하였 다. 또한 다양한 지능을 자극하는 교육적 접근은 통합적 사고력과 실행 력을 향상시키면서 개인의 강점을 기반으로 한 성장 가능성도 함께 확장 해 나갈 수 있을 것이다. 다중지능 이론의 효과적 적용을 위해서는 학습 자의 개별성 존중, 개인 내외의 상호작용 및 협력 강화, 교수·학습 방법 의 다양화 등이 필요할 것이다. 본 연구는 대학 교양교육의 교육적 방향 과 발전 과제를 모색하는 데 있어 다양한 지능을 존중하는 교수·학습 환 경 조성을 위한 기초 자료로 활용될 수 있을 것이다.

본 연구는, 장애역설이론적 관점에서, 정신장애인의 사회활동참여가 주 관적 삶의만족에 미치는 영향을 살펴보고, 이 과정에서 장애수용과 자아 존중감의 다중매개효과를 검증하고자 하였다. 장애인삶 패널조사 데이터 의 정신장애인 264명을 대상으로 SPSS 및 PROCESS macro 모델4를 적용하여 회귀분석과 부스트래핑을 실시하였다. 주요 결과는 첫째, 정신 장애인의 사회활동참여가 주관적 삶의만족에 미치는 영향력은 유의하지 않았다(B=0.16, p=.357). 둘째, 정신장애인의 사회활동참여와 주관적 삶 의만족의 관계에서 자아존중감의 완전매개 효과가 있음이 검증된 반면, 장애수용은 매개효과가 없는 것으로 나타났다. 이러한 결과를 바탕으로, 정신장애인의 주관적 삶의만족감 향상과 자아존중감 향상을 위한 방안 및 제언을 고찰하였다.

본 연구는 조직구성원이 인식하는 직무복잡성이 긴장, 피로를 매개로 직무만족 및 이직의도에 미치는 영향을 분석하는 것을 목적으로 한다. 특히, 직무복잡성이 이직의도에 미치는 영향에서 직무 스트레스 반응인 긴장, 피로의 양면적 경로를 확인하였다. 이를 위해 인적자본 기업패널조 사(Human Capital Corporate Panel; HCCP) 중 2023년 조사된 HCCP 3차 근로자 패널 데이터를 활용하여 9,512명의 직장인 설문 결과를 분석 하였다. 분석 결과, 직무복잡성으로 인해 발생 된 긴장은 직무만족을 통 해 이직의도를 낮추는 반면, 직무복잡성으로 인해 발생 된 피로는 직무 만족을 통해 이직의도를 높이는 상반된 결과를 보였다. 본 연구는 직렬 다중매개효과를 사용하여 직무복잡성과 긴장, 피로, 직무만족, 이직의도 간의 구조적 관계를 규명하였다는 점에 의의가 있다. 또한, 직무 복잡성 의 양면적 특성을 밝힘으로써, 조직구성원의 직무만족을 높이고 이직의 도를 감소시키기 위한 학문적·실무적 시사점을 제공하였다.

본 연구는 성인학습자의 자아존중감과 삶의 질의 관계에서 가 족응집력의 매개효과를 알아보고자 하였다. 연구는 2025년 1월 부터 2025년 2월까지 진행되었다. 연구대상은 G시에 소재한 지 역의 요양원에 종사하는 성인학습자 243명을 임의표집하였으며, 자료분석을 위해 SPSS Statistics 21.0을 사용하였다. 다중매개 효과 분석을 위해서는 PROCESS macro의 병렬 다중매개모형 검증방법(Model 4번)을 사용하였다. 성인학습자의 자아존중감과 삶의 질의 관계에서 가족응집력 다중매개효과를 살펴본 결과, 가 족응집력 하위변인은 다중매개하는 것으로 나타났으며, 성인학습 자의 삶의 질은 자아존중감 뿐만 아니라 가족응집력 하위변인에 영향을 받는 것으로 나타났다. 성인학습자는 가족응집력을 매개 로 삶의 질과 연결될 수 있음을 알 수있다.

Background: Multiple fractures, particularly femoral fractures, are increasingly prevalent and associated with high mortality rates and significant functional impairments. This highlights the urgent need for effective rehabilitation strategies, such as robot-assisted training, to enhance recovery and improve quality of life. Objectives: This study aimed to evaluate the clinical effectiveness of robotassisted rehabilitation for multiple femoral fractures. Design: Single-subject design. Methods: A 15-day A-B-A' single-subject design was employed. A man in his 30s with multiple fractures underwent standard rehabilitation during the baseline (A) and regression baseline (A') phases, with robotic therapy introduced during the intervention phase (B). Daily assessments of mobility and balance were analyzed using the two-standard deviation method. Results: Robotic therapy led to significant improvements: the TUG test time decreased from 16.21±0.64 seconds (A) to 10.63±0.46 seconds (B) and 9.64±0.35 seconds (A'). The 10 MWT time improved from 6.31±0.64 seconds (A) to 5.41±0.17 seconds (B) and 5.01±0.12 seconds (A'). LOS increased from 364.01±35.83 cm² (A) to 484.67±29.97 cm² (B) and 518.03±18.82 cm² (A'). Plantar pressure imbalance (59.2% right, 40.8% left in A) was corrected to nearly equal distribution in B (49.4%/50.6%) and A' (50.8%/49.2%). Conclusion: Robotic rehabilitation therapy improves balance and weightbearing capacity in patients with multiple fractures, suggesting its effectiveness as an early intervention following bone union.

This case report discusses a 15-year-old female poodle with multifocal degenerative myelopathy, who achieved significant clinical improvement through intensive acupuncture and rehabilitation therapy. The patient presented with ataxia in both hind limbs, and imaging studies revealed multiple regions of disc protrusion. Rather than surgical intervention, conservative treatment was chosen, which included acupuncture, medication, and laser therapy. Following treatment, notable improvements in neurological symptoms and pain reduction were observed. This case highlights the potential effectiveness of non-surgical approaches in managing degenerative myelopathy.

Silage inoculants, which include beneficial microorganisms like lactic acid bacteria (LAB), play a vital role in modern silage production by enhancing fermentation quality. This study evaluated the effectiveness of various commercial inoculants on the fermentation dynamics of Italian ryegrass silage over 45 days. The treatments included a control group and five inoculant formulations: T1 (Lactiplantibacillus plantarum), T2 (Lactiplantibacillus plantarum and Pediococcus pentosaceus), T3 (Lactiplantibacillus plantarum and Pediococcus pentosaceus and Lactiplantibacillus buchneri), T4 (Lactiplantibacillus plantarum and Lactiplantibacillus acidophilus and Lactiplantibacillus bulgaricus), and T5 (Lactiplantibacillus plantarum and Pediococcus pentosaceus and Enterococcus faecium). After 45 days, all treatment groups exhibited significantly higher crude protein (CP) content compared to the control group (80.64 g/kg dry matter (DM), p<0.05). Treatments T2 and T5, which incorporated combinations of Lactiplantibacillus plantarum, Pediococcus pentosaceus and Enterococcus faecium, showed higher CP contents at 105.53 and 107.05 g/kg DM, respectively. The inoculated silages also demonstrated a rapid pH reduction within the early days, with Lactiplantibacillus plantarum in T1 reducing the pH to 4.0 within four days. Additionally, inoculated treatments had significantly higher lactic acid levels than the control (67.96 g/kg DM, p<0.05), and T3 (Lactiplantibacillus buchneri) produced higher acetic acid levels (16.07 g/kg DM, p<0.05) than other inoculants. The control group also had a notably higher ammonia nitrogen content. In conclusion, while single-strain inoculants like Lactiplantibacillus plantarum are effective for rapid acidification, the use of combined bacterial strains can further enhance silage quality by improving lactic acid fermentation and nutrient preservation, particularly in treatments like Lactiplantibacillus plantarum and Pediococcus pentosaceus and Lactiplantibacillus buchneri and Enterococcus faecium.

As various types of products are produced in a single production system, it is important to determine a scheduling policy that selects one of the different types. In addition, the failure of processes in a line need to be considered due to machine failure, raw material supply and demand, quality issues, and worker absence, etc. Therefore, we studied production systems with various product types, dedicated buffers for each product type, Bernoulli equipment, and WIP-based scheduling or cyclic scheduling. To analyze such system exactly, we introduced a method to analyze the performance such as production rate, WIP level, blocking probability and starvation probability based on Markov chains and derived various characteristics. Especially, assuming that equipment does not need to select the type it just tried, the flow rate is no longer conserved and increasing buffer capacity does not guarantee increase production rate. The performance comparison between WIP-based and cyclic policy is studied as well.

In this work the multiple moving magnetic abrasive machining (MAM) process was used to polish the surface of spherical bar that is the components that widely used in many applications such aerospace, medical implantation, and the mechanical engineering industries. The smooth surface of spherical ball plays an important role for improving the lifespan, durability, and functionality of the components. In. Therefore, the moving MAM process was fabricated to achieve high quality surface of the spherical ball sample. This process used the multiple moving actions of the machining tools for polishing the surface sample. The experiments used in this work was set as the rotational speed of sample (50, 120, and 250 rpm), movement of machining tools (X-axis: 12 mm/sec, Y-axis: 12 mm/sec), and the polishing times (0, 2, 4, 6, 8 min). The results demonstrated that within 6 min of the polishing time the surface roughness of sample was significantly reduced from 0.29 μm to 0.02 μm under the polishing action of machining abrasive tool (size: 1-μm). This can be concluded that the multiple moving MAM process is an effective method to achieve high surface quality of sample with extremely low surface roughness (Ra).

The multi-local resonance metamaterial is based on the local resonance mechanism of resonators, effectively blocking wave propagation within multiple resonant frequency ranges, a phenomenon known as band gaps. In practical applications for vibration reduction, the goal is to achieve wide-band vibration attenuation at low frequencies. Therefore, this study aims to improve the vibration reduction performance of multi-local resonance metamaterials by lowering the band gap frequency and expanding the band gap width. To achieve this, an objective function was formulated in the optimization problem, considering both the frequency and width of the band gap, with the geometric shapes of the multiple local resonators selected as design variables. The Sequential Quadratic Programming (SQP) technique was employed for optimization. The results confirmed that the band gap was generated at lower frequencies and that the band gap width was expanded.

This study aims to analyze the natural frequency characteristics of multi-cracked extensible beams. The model and governing equations of the multi-cracked beam were derived using Hamilton's principle while considering crack energy. The eigenmode functions were obtained through eigenvalue analysis by applying the patching conditions of the cracks, and the equations for the discretized cracked beam were formulated and solved. The displacement responses from nonlinear system analysis were used to calculate frequencies via Fast Fourier Transform (FFT), and the frequency characteristics were systematically analyzed with respect to the number of cracks, crack depth, and cross-sectional loss. Additionally, the natural frequencies and orthonormal bases of the linear system were derived by exploring the solutions of the characteristic equation reflecting the cracks. Numerical analyses showed that the natural frequency of a cracked extensible beam was higher than that of a cracked EB beam. However, as the number or depth of cracks increased, the natural frequency gradually decreased. Notably, in extensible beams with large deflections, the dynamic changes caused by cracks demonstrated results that could not be obtained through the EB beam model.

This study aims to develop a regression model using data from the Ammunition Stockpile Reliability Program (ASRP) to predict the shelf life of 81mm mortar high-explosive shells. Ammunition is a single-use item that is discarded after use, and its quality is managed through sampling inspections. In particular, shelf life is closely related to the performance of the propellant. This research seeks to predict the shelf life of ammunition using a regression model. The experiment was conducted using 107 ASRP data points. The dependent variable was 'Storage Period', while the independent variables were 'Mean Ammunition Velocity,' 'Standard Deviation of Mean Ammunition Velocity,' and 'Stabilizer'. The explanatory power of the regression model was an R-squared value of 0.662. The results indicated that it takes approximately 55 years for the storage grade to change from A to C and about 62 years to change from C to D. The proposed model enhances the reliability of ammunition management, prevents unnecessary disposal, and contributes to the efficient use of defense resources. However, the model's explanatory power is somewhat limited due to the small dataset. Future research is expected to improve the model with additional data collection. Expanding the research to other types of ammunition may further aid in improving the military's ammunition management system.