This study investigated the impact of various soil environmental factors on the growth and yield of Actinidia arguta (A. arguta) in Suwon, South Korea. By employing Pearson correlation analysis, we explored the relationships between soil properties such as pH, electrical conductivity (EC), organic matter content, available phosphorus, available silicon, soil moisture, and soil temperature with A. arguta growth and yield. The results revealed that soil temperature and EC had the strongest positive correlations with A. arguta growth, while organic matter content exhibited a strong negative correlation with fruit yield. The high levels of available phosphorus emerged as a potential adverse factor affecting yield. These findings suggest that managing soil temperature, EC, and phosphorus levels is crucial for optimizing A. arguta productivity. Future research should focus on fine-tuning phosphorus levels and further investigating the interactions between soil factors to enhance A. arguta yield and sustainability.

Defense Modeling & Simulation (M&S) techniques are used for developing the efficiency and economics of national defense at operational level so that it maintains interoperability and reusability in sustainability for the following process of the war simulation. However, the lack of conceptual models was one cause of limiting the interoperability and reusability in defense M&S areas. In this paper, the Conceptual Model of the Mission Space (CMMS) is studied as preliminary process for the defense M&S. The conceptual modeling framework called CMMS-K (Conceptual Model of the Mission Space-Korea) is suggested using a case example in consideration of the Korean Army specification and characteristics. The practicality of CMMS-K is evaluated through the ontology development for military scenarios. It is expected that the gap between the theoretical approach and the practical perspective of defense M&S can be diminished through the use of these approaches.

Reinforced concrete (RC) columns exhibit cyclic damage, such as strength degradation, under cyclic lateral loading, such as earthquakes. Considering the cyclic damage, the nonlinear load-deformation response of RC columns can be simulated using a lumped plasticity model. Based on an experimental database, this study calibrates lumped plasticity model parameters for 371 rectangular and 290 circular RC columns. The model parameters for adequate flexural rigidity, plastic rotation capacity, post-capping rotation capacity, moment strength, and cyclic strength degradation parameter are adjusted to match each experimentally observed load-deformation response. We have developed predictive equations that accurately relate the model parameters to the design characteristics of RC columns through regression analyses, providing a reliable tool for engineers and researchers. To demonstrate their application, the proposed and existing models numerically simulate the earthquake response of a bridge pier in a metropolitan railway bridge. The pier is subjected to several ground motions, increasing intensity until collapse occurs. The proposed lumped plasticity model showed about 41% less vulnerable to collapse.

늘어나는 교통 수요에 대응하기 위해 지하도로 건설이 추진 중이다. 지하도로 건설 시, 진출입부에서의 차량 간 합류 및 분류로 인해 교통정체 및 안전성 저하에 대한 우려가 제기된다. 교통정체가 빈번히 발생하는 경부고속도로 금토JCT-양재IC 구간에 서울-용인 지 하도로, 양재-한남 지하도로, 양재-고양 지하도로 건설이 예정되었다. 특정 구간에 다수의 지하도로 건설 시, 접속부 배치 및 위치에 따라 이동성 및 안전성이 변화할 것으로 고려된다. 본 연구에서는 서울-용인 지하도로와 양재-한남 지하도로, 양재-고양 지하도로에 대한 접속부 배치 및 위치에 따른 이동성 및 안전성 분석을 통해 교통혼잡 완화 및 교통안전이 증가하는 지하도로 연계 방안 도출하 였다. 본 연구에서는 지하도로 연계 방안별 이동성 및 안전성 분석을 위해 4가지 시나리오 (1안 : 지하도로 미시행, 2안 : 지하도로 미 연계, 3안 : 양재-고양 연계, 4안 : 양재-한남 연계)를 선정하였다. 교통 시뮬레이션을 활용해 지상도로 및 지하도로 네트워크를 구축 하고 지하도로 내 차량 주행행태를 구현하였다. 이동성은 평균 통행속도와 통과교통량비로 분석하였으며, 안전성은 상충률을 통해 분 석하였다. 이동성 분석결과, 지상도로 합류부에서는 시나리오 3안 (양재-고양 연계)이 지하도로에서 합류되는 교통량이 가장 적어 모 든 이동성 평가지표에서 가장 큰 이동성 개선 효과가 나타났다. 그러나, 지하도로 합류부에서는 시나리오 3안에 비해 시나리오 4안 (양재-한남 연계)이 이동성 개선 효과가 큰 것으로 나타났다. 이는 유사 교통량 대비 차로수 증가 및 지상도로 합류부 정체의 영향인 것으로 분석된다. 안전성 분석결과, 지상도로 합류부에서는 시나리오 3안이 안전성이 높았으나 지하도로 합류부에서는 시나리오 4안이 안전성이 더 높은 것으로 나타났다. 본 연구의 결과는 시나리오별 교통혼잡 완화 및 교통안전 증진 효과를 정량화해 지하도로 연계 방안 결정을 위한 예비타당성 조사에 반영하는 자료로 활용할 수 있을 것으로 기대된다.

본 연구에서는 전지구 해양 예측 모델 결과를 동아시아 지역 해양 모델인 ROMS의 초기 및 경계 조건에 적용 한 역학적 규모 축소 모의 실험을 수행하였다. 우선 ROMS 모델의 성능을 AMOR3D, EN4, 정선 관측 자료, 인공위성 영상 및 기존에 발표된 MOHID 모델과 비교하여 검증하였다. 전반적으로 봄과 가을에는 관측 자료와 잘 일치하였으나, 해양 성층화가 강화되는 여름에는 모델 성능이 저하되는 것을 확인하였다. 또한, 동해와 남해보다 황해에서 더 우수한 성능을 보였으며, MOHID 모델보다 아표층 모의 성능이 개선되었다. RCP 4.5 시나리오를 적용하여 2015년부터 2030 년까지 예측한 CM2.1 전지구 해양 모델의 결과를 사용한 역학적 규모 축소 모의를 수행한 결과, 한반도 남서 연안의 저수온 영역, 황해난류의 경로 및 쿠로시오 해류의 사행 등 실제 해양의 다양한 현상이 잘 재현되었다. 또한, 지역 모델은 저해상도 전구 모델보다 평균 수온의 경년 변동 폭이 커지는 것을 확인하였다. 본 연구를 통해 ROMS를 이용한 역학적 규모 축소 결과의 신뢰성이 확인되었으나, 향후 동해 및 남해와 같은 특정 지역의 ROMS 모델의 모의 성능 개 선과 2030년 이후의 장기 시뮬레이션 연구가 추가로 필요할 것으로 보인다.

Until all vehicles are equipped with autonomous driving technology, there will inevitably be mixed traffic conditions that consist of autonomous vehicles (AVs) and manual vehicles (MVs). Interactions between AVs and MVs have a negative impact on traffic flow. Cloverleaf interchanges (ICs) have a high potential to cause traffic accidents owing to merging and diverging. Analyzing the driving safety of cloverleaf ICs in mixed traffic flows is an essential element of proactive traffic management to prevent accidents. This study proposes a comprehensive simulation approach that integrates driving simulation (DS) and traffic simulation (TS) to effectively analyze vehicle interactions between AVs and MVs. The purpose of this study is to identify hazardous road spots for a freeway cloverleaf IC by integrating DS and TS in mixed traffic flow. The driving behavior data of MVs collected through a DS were used to implement vehicle maneuvering based on an intelligent driver model in the TS. The driving behavior of the AVs was implemented using the VISSIM parameters of the AVs presented in the CoEXist project. Additionally, the market penetration rate of AVs, ranging from 10% to 90% in 10% increments, was considered in the analysis. Deceleration rate to avoid crashes was adopted as the evaluation indicator, and pinpointing hazardous spot technique was used to derive hazardous road spots for the cloverleaf IC. The most hazardous road spot was identified in the deceleration lane where greater speed changes were observed. Hazardous road spots moved downstream within the deceleration lane as traffic volumes increased based on level of service. The number of AVs decelerating stably increased as traffic increased, thereby improving the safety of the deceleration lane. These results can be used to determine the critical point of warning information provision for preventing accidents when introducing AVs.

The seismic performance of lead-rubber bearings (LRBs) is significantly affected by both the axial force and loading rate they experience. Accurate assessment of LRBs’ seismic performance, therefore, requires realistic simulation of these forces and rates, as well as of the response of the isolated structure during seismic events. This study conducted a series of real-time hybrid simulations (RTHS) to evaluate the seismic behavior of LRBs in such conditions. The simulations focused on a two-span continuous bridge isolated by LRBs atop the central pier, exposed to horizontal and vertical ground motions. In the RTHS framework, the LRBs were physically tested in the laboratory, while the remainder of the bridge was numerically modeled. Findings from these simulations indicated that the vertical ground motion had a minimal effect on the lateral response of the bridge when isolated by LRBs.

Being in a stable continental region (SCR) with a limited history of instrumentation, South Korea has not collected sufficient instrumental data for data-driven ground motion models. To address this limitation, we investigated the suitability of the hybrid ground motion simulation method that Graves and Pitarka (2010, 2015) proposed for simulating earthquake ground motions in South Korea. The hybrid ground motion simulation method used in this study relies on region-specific parameters to accurately model phenomena associated with the seismic source and the wave propagation. We initially employed relevant models and parameters available in the literature as a practical approach. We incorporated a three-dimensional velocity model developed by Kim et al. (2017) and a one-dimensional velocity model presented by Kim et al. (2011) to account for the crustal velocity structure of the Korean peninsula. To represent the earthquake source, we utilized Graves and Pitarka’s rupture generator algorithm along with a magnitude-area scaling relationship developed for SCR by Leonard (2014). Additionally, we assumed the stress and attenuation parameters based on studies of regional seismicity. Using the implemented platform, we simulated the 2016 Mw5.57 Gyeongju earthquake and the 2017 Mw5.4 Pohang earthquake. Subsequently, we compared results with recorded accelerations and an empirical ground motion prediction equation at strong motion stations. Our simulations had an overall satisfactory agreement with the recorded ground motions and demonstrated the potential of broadband hybrid ground motion simulation for engineering applications in South Korea. However, limitations remain, such as the underestimation of long-period ground motions during the 2017 Pohang earthquake and the lack of a model to predict the ground motion amplification associated with the near-surface site response accurately. These limitations underscore the importance of careful validation and refinement of region-specific models and parameters for practically implementing the simulation method.

Sequential zone picking is an order picking method designed to enhance warehouse efficiency by dividing the storage area into multiple zones and picking items in a sequential order across these zones. Picked items are often placed in dedicated totes and transported between zones using a conveyor system, which manages the picking flow but can occasionally result in inefficiencies during the process. This study presents a variant of the sequential zone picking system, called a dual-lane zone picking system (DZP), which consists of two parallel conveyor lanes without buffers between consecutive zones. This conveyor configuration allows the picker in each zone to alternate processing between the two lanes, thereby lessening the constraints of tote transitions between zones and improving both system throughput and picker utilization. We design and conduct a series of experiments using a discrete-event simulation model to evaluate the performance of DZPs. The experiment results indicate that DZP surpasses the original single-lane zone picking system by shortening the system’s mean flow time in low flow intensity scenarios and achieving a higher maximum throughput and worker utilization in high flow intensity scenarios. Additionally, we investigate the effects of the number of zones and order batching size on the performance of DZP to gain further insights into the system’s operational control.

A multi-criteria decision-making(MCDM) method allows the decision makers to systematically evaluate the alternatives based on a predefined set of decision criteria. The most commonly used MCDM methods include Analytic Hierarchy Process(AHP), Technique for Order of Preference by Similarity to Ideal Solution(TOPSIS), Weighed Aggregated Sum Product Assessment(WASPAS), Preference Selection Index(PSI), etc. In MCDM Problems, it is common that performance ratings for different criteria are measured by different units. Normalization is thus used to convert performance ratings into commensurable data. There are many normalization techniques that can be used for MCDM problems. Much effort has been made for comparative studies on the suitability of normalization techniques used in MCDM methods. However, most studies present normalization methods suitable for specific MCDM problems based on specific data samples. Therefore, this study proposes the most suitable normalization method for each MCDM method under consideration using extensive data samples. A wide range of MCDM problems with various measurement scales are generated by simulation for comparative study. The experimental results show that vector normalization method is best suited for all MCDM methods considered in this study.

본 연구는 간호대학생의 게임 기반 시뮬레이션 학습 경험을 분석하여 그 의미를 도출한 질적 연구이다. 연구 참여자는 총 18명으로, 게임 기반 시뮬레이션 수업에 참여한 간호대학생이었다. 연구 자료 는 2023년 6월부터 7월까지 포커스 그룹 인터뷰를 통해 수집되었으며, 질적 내용분석 방법을 사용하여 분 석하였다. 연구 결과, 재미, 몰입, 경쟁, 협력, 학습성과 총 5개 주요 영역에서 10개의 범주와 18개의 유의 미한 진술이 도출되었다. 결론적으로, 게임 기반 시뮬레이션 수업은 간호학생들의 재미를 통해 학습 몰입 과 동기 부여를 높이고, 실제적 협력을 경험하게 하며, 다각적인 학습성과를 거두게 하였다. 따라서 본 연 구는 간호교육에서 게임 기반 시뮬레이션을 기존 시뮬레이션 학습의 대안으로 활용할 가능성을 제시하며, 게임 기반 학습성과를 심층적으로 검증하기 위한 후속 연구를 제언한다.

본 연구는 해양에서 선박 운항 시 발생할 수 있는 항행장애물, 특히 부유물과의 충돌 위험성을 예측하기 위해 몬테카를로 시뮬 레이션을 적용한 항행안전 충돌 확률 모델을 개발하는 데 중점을 두고 있다. 항행장애물은 해양에서 선박의 운항을 방해하거나 위험을 초 래할 수 있는 물체로, 선박 사고의 주요 원인 중 하나이다. 연구는 부유물 감김 사고와 관련된 최근 5년간의 해양사고통계 정보와 7년간 사 고 데이터를 분석하여 사고 발생 패턴을 파악하고, 이를 기반으로 위험성 평가 방법론을 검토하였다. 몬테카를로 시뮬레이션을 통해 임의 의 제한된 해상 공간 내에서 표류하는 부유물과 이동 중인 선박이 접촉할 확률을 도출하였으며, 다양한 변수(부유물의 크기, 개수, 속도, 이 동하는 선박의 개수, 선박의 통항 패턴 등)가 충돌 확률에 미치는 영향을 분석하였다. 연구 결과, 표류하는 장애물의 속도보다는 장애물의 크기와 이동하는 선박의 개수에 따라 충돌 확률이 영향을 받음을 확인할 수 있었다. 이 연구는 해양과 선박 데이터 기반 실행 가능한 모델 을 제안하며, 이를 통해 선박 운항의 안전성을 높이고, 사고 예방을 위한 효과적인 관리 방안을 제공하는 것을 목표로 하고 있다.

The MBR process, which uses membrane to separate solids instead of secondary clarifier, has the advantage of maintaining high MLSS (Mixed Liquor Suspended Solids) concentration in bioreactors. In this study, three MBR processes combined with chemical phosphorus removal facility were studied: the phase-isolated MBR process with one recirculation pump, the A2O MBR process with two recirculation pumps, and the MBR process without a oxygen depletion reactor with three recirculation pumps. 116 simulations by EQPS (Effluent Quality Prediction System) were performed, under same design influent characteristics and hydraulic retention time, to see the effects of recirculation ratio changes on effluent water quality. The final effluent limits for total nitrogen and phosphorus were set to as 10 ㎎/L or less and 0.2 ㎎/L or less, respectively. AlCl3 was fed at MBR effluent to make 0.2 ㎎/L of total phosphorus precisely by PI (Proportional-Integral) controller in EQPS. This study showed that the phase isolated MBR process (R1 600%) had the highest nitrogen removal efficiency, with a final effluent T-N concentration of 6.765 mg/L. However, the A2O MBR process (R1 400%, R2 100%) required the lowest AlCl3 flow of 0.742 m3/day, which is approximately 59.1% lower than the average AlCl3 flow of the phase-isolated MBR process. It also produced 4,835 kg/day of sludge, the lowest among the studying MBR processes. It seems that A2O MBR process is the most economic method to treat studying wastewater to meet final effluent nutrient limit targets. However, carbon neutrality must be considered to select the best process to treat studying wastewater and it will be presented later.

Purpose: This study aimed to analyze the reviewers’ evaluations of papers submitted to the Journal of the Korean Society for Simulation in Nursing between 2019 and June 2024. Methods: We analyzed 117 quantitative (69 published and 48 unpublished) and 16 qualitative (11 published and five unpublished) studies. The reviewers’ checklist-based evaluations were analyzed using means and standard deviations. The scope method was used to examine the reviewers’ subjective evaluations. Results: For quantitative studies, the highest average score among published papers was in the “Research Theme” category (3.64±0.73). Contrastingly, the lowest average scores were in the “Discussion” category, with 3.32±0.74 for quantitative studies and 3.23±0.74 for qualitative studies. In rejected papers, the “Discussion” category recorded the lowest scores, at 2.35±0.74 for quantitative studies and 1.92±0.76 for qualitative studies. Conclusion: The results demonstrated the research characteristics of this journal and focus of the review by providing information on the reviewers’ evaluations. Structured scientific research based on these results will contribute to improving the academic quality of journals by reinforcing the openness and systematicity of academic communication.

Purpose: This study aimed to evaluate the effectiveness of low-fidelity simulation and actual human practice on the learning outcomes of a peripheral intravenous injection program for nursing students. Methods: Seventy-two third-year nursing students from a university in Seoul were included and divided into two groups; 38 and 34 in the low-fidelity simulation and human practice groups, respectively. The program was conducted from June 19–20, 2024. Data were analyzed using frequency, percentage, mean, standard deviation, χ²-test, independent t-test, and ANCOVA. Results: Both groups showed significant improvements in venipuncture performance, communication skills, empathy, academic performance, and self-efficacy. However, there were no statistically significant differences in these outcomes between both groups. Additionally, post-program learning satisfaction was similarly high in both groups. Conclusion: Low-fidelity simulation is as effective as actual human practice in achieving comparable learning outcomes in a peripheral intravenous injection program for nursing students. With appropriate instructional design, low-fidelity simulation can be a viable alternative to human practice, providing flexibility and accessibility in nursing education. This study underscores the importance of incorporating additional educational modules that enhance emotional and social skills, such as communication and empathy, tailored to the characteristics of individual learners.

Purpose: This study aimed to identify the need for simulation education to strengthen patient safety competencies in nursing practice field experience and explore and analyze improvements in simulation education. Methods: Data were collected through focus group interviews with 31 participants from four groups of fourth-year nursing students and one group of new nurses from August 7, 2023 to February 11, 2024. Interview data were systematically reviewed by qualitative content analysis. Results: Five major themes were identified; (1) awareness of patient safety competencies among nursing students and new nurses, (2) awareness of patient safety education among nursing students and new nurses, (3) simulation education topics for strengthening patient safety competencies, (4) interfering factors of simulation education for strengthening patient safety competencies, and (5) facilitating factors of simulation education to strengthen patient safety competencies. Accordingly, 15 categories were derived, and the current status of simulation education for patient safety, educational needs, and improvements were reported. Conclusion: This study attempted to reflect on the needs of learners before developing a simulation education program and derive educational content to strengthen patient safety competencies.

Purpose: This single-group pre-post experimental study aimed to develop and apply a simulation-based infection control education program for neonatal intensive care unit (NICU) nurses to verify its effectiveness and provide baseline educational materials to strengthen NICU nurses’ infection control competencies. Methods: The educational program was developed according to the five phases of analysis, design, development, implementation, and evaluation models, with scenarios based on the educational needs of NICU nurses. To verify the program’s effectiveness, a study was conducted on 28 NICU nurses of general and tertiary hospitals. NICU nurses’ infection control knowledge, performance confidence, critical thinking disposition, and satisfaction with the education were surveyed after applying the education program. Results: The simulation-based NICU infection control educational program was effective for NICU nurses’ infection control knowledge (t=−7.35, p < .001), performance confidence (t=−6.30, p < .001), and critical thinking disposition (t=−5.12, p < .001). Conclusions: The infection control educational program can contribute to infection prevention and patient safety by improving the NICU nurses' infection control competencies and be used as a baseline educational material for infection control education.

음이온 교환막(AEM) 수전해용 AEM 소재 개발은 재생 에너지를 활용한 수소 생산 기술을 개선하는 데 중요한 역할을 한다. 이러한 소재를 설계하고 최적화하는 데 분자동역학 전산모사가 유용하게 사용되지만, 전산모사 결과의 정확도 는 사용된 force-field에 크게 의존한다. 본 연구의 목적은 AEM 소재의 구조와 이온 전도 특성을 예측할 때 force-field 선택 이 미치는 영향을 체계적으로 조사하는 것이다. 이를 위해 poly(spirobisindane-co-aryl terphenyl piperidinium) (PSTP) 구조를 모델 시스템으로 선택하고 COMPASS III, pcff, Universal, Dreiding 등 네 가지 주요 force-field를 비교 분석하였다. 각 force-field의 특성과 한계를 평가하기 위해 298~353 K의 온도 범위에서 수화 채널 형태, 물 분자와 수산화 이온의 분포, 수산 화 이온 전도성을 계산하였다. 이를 통해 AEM 소재의 분자동역학 전산모사에 가장 적합한 force-field를 제시하고, 고성능 AEM 소재 개발을 위한 계산 지침을 제공하고자 한다.