• The Journal of Industrial Distribution & Business
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• v.9 no.4
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• pp.53-62
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• 2018

Purpose - In the development of new products, suppliers involvement and developing products jointly can be said to be strategic activities that utilize the lack of knowledge from external organizations. In this new product development, supplier involvement has been proven to have a positive impact on new product development performance for a long time by previous research. However, sufficient academic research has not been conducted on the influence of supplier involvement in various product strategies or sales strategies that buyers make in order to secure a competitive advantage in the market. This study argues that product strategy and sales strategy used by buyers in the development of new products will control the effect of supplier involvement on new product development performance in order to compensate the lack of these academic aspects. Research design, data, and methodology - Specifically, we selected the modularization strategy of the product as the product strategy, which is considered as an important strategy in the new product development through the preceding research, and the mass customer satisfaction strategy was chosen as the sales strategy. In order to achieve these research objectives, regression analysis was conducted using data from manufacturing productivity panel collected jointly by the Ministry of Industry, Trade and Industry and the Korea Productivity Center. Results - As a result, supplier involvement and new product development performances (development cost efficiency, customer satisfaction) were positively related. The product modularity strategy proved to have an interactive effect on the relationship between supplier involvement and new product development performances (development cost efficiency, customer satisfaction). However, it has not been confirmed that there is a statistically significant interaction effect between supplier involvement and new product development performances. Conclusions - Supplier involvement has positive relationships with NPD performance. In addition, product modularity strategies have interaction effects with supplier involvement and affect new product development performance (development cost efficiency and customer satisfaction). The results of this study are of academic significance in the case of lack of empirical studies on the effect of supplier participation on the effect of buyer 's strategy when a supplier participates and develops new products jointly.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.644-648
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• 2004

In the present study were examined numerically and experimentally the off-design performance characteristics on an axisymmetric plug nozzle with variable throat area. In this nozzle concept, its throat area can be changed by translating the plug into the axial direction. First, a mixed-expansion plug nozzle, in which two expansion parts are arranged both inside and outside, was designed by means of the method of characteristics. Second, the CFD analysis was verified by the cold-flow wind tunnel test. Third, its performance characteristics were evaluated over a wide range of pressure ratio from half to double throat area through the design point, using the CFD code verified by the wind tunnel tests. It was made clear from the study that not so critical thrust efficiency losses were found and the maximum thrust efficiency loss was at most approximately 5 % under off-design conditions without external flow. This result shows that a plug nozzle can give the altitude compensation even under off-design geometry operations. However, shock waves were observed in the inner expansion part under the doubled throat area operation and thus some thermal problems may be caused on the plug surface. Furthermore, collapse of cell structure on the plug surface was observed with external flow (around Mach number 2.0) as it became lower pressure ratio below the design point and the fact may result in big efficiency loss regardless of geometrical configuration.

• Journal of Drive and Control
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• v.20 no.3
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• pp.35-41
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• 2023

Radish and Chinese cabbage are the most produced and consumed vegetables in Korea. The mechanization of harvesting operations is necessary to minimize the need for manual labor. This study to develop and evaluate the performance of a multi-purpose driving platform that can apply modular Radish and Chinese cabbage harvesting devices. The multi-purpose driving platform consisted of driving, device control, engine, hydraulic, harvesting, conveying, and loading part. Radish and Chinese cabbage harvesting conducted using the multi-purpose driving platform each harvesting module. The performance of the multi-purpose driving platform was evaluated the field efficiency and loss rate. The total Radish harvesting operation time 34.3 min., including 28.8 min., of harvesting time, 1.9 min., of turning time, and 3.6 min., of replacement time of bulk bag. During Radish harvesting, the field efficiency and average loss rate of the multi-purpose driving platform were 2.0 hr/10a and 3.1 %. Chinese cabbage harvesting operation 49.3 min., including 26.6 min., of harvesting time, 4.6 min., of turning time, and 18.1 min., of replacement time of bulk bag. During Chinese cabbage harvesting, the field efficiency and average loss rate of the multi-purpose driving platform 2.1 hr/10a and 0.1 %. Performance evaluation of the multi-purpose driving platform that harvesting work was possible by installing Radish and Chinese cabbage harvest modules. Performance analysis through harvest performance evaluation in various Radish and Chinese cabbage cultivation environments is necessary.

• Applied Chemistry for Engineering
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• v.3 no.2
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• pp.349-359
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• 1992

Studies were carried out on the selective removal of inorganic salts such as NaCl and $Na_2SO_4$ from dye solution, using counter diffusion-reverse osmosis and nanofiltration, respectivey. For the dye solution used in the experiments, 1 to 30% of salts were removed by counter diffusion while the loss of dye molecules was less than 0.3%. The separation factors by one pass operation were 10-500 according to ionic species. In five successive operations, removals of anion($Cl^-$) increased but those of cation($Na^+$) decreased due to the Donnan effect. Effects of feed flow rate on removal efficiencies of various ions were also observed at constant flow rate of stripping water. Reverse osmosis of desalted dye solution by counter diffusion was conducted to prepare highly concentrated liquid dyes. The rejection efficiency of dye molecules was greater than 99%. For the rejection efficiency of chloride ion, experimental values were compared with theoretical ones based on solution-diffusion model. Two stage diafiltration was performed in nanofiltration. The rejection efficiency of chloride ion was continuously decreased due to the Donnan dialysis and even negative rejection was observed. The Donnan effect was more pronounced in the second diafiltration.

• Journal of agriculture & life science
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• v.53 no.6
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• pp.35-44
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• 2019

The objectives of this study were to identify engineering problems in the design and installation of cable logging operation that affects productivity through case study of actual logging sites, and to analyze associated productivity loss and increased cost. As a result of the study, when the geographic conditions and engineering safety of the site are not sufficiently considered, deflection of the cable line can not be secured. Hourly productivity of the operation decreased to 65% and the logging cost increased by more than two times compared to the productive yarding operation, which lowered overall efficiency of the operation. Thus, it is required to spread filed technologies that minimize unnecessary production cost incurred due to the in-efficient logging operations as well as secure work safety and efficiency to expand cable logging operation throughout the country.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.10
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• pp.107-115
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• 2013

Recently, the RFID technology is combined with a u-healthcare services is an emerging trend in the field of medical services. u-healthcare service, as covering the field of personal health information beyond the level of simple health screening and treatment of life are closely related. Considering security, invasion of privacy, as well as life may be threatened even if your personal health information to be exposed or exploited illegally u-Healthcare services certification is essential. In 2012, Jeong proposed J-L patient authentication protocol that Initialization process, and patients using RFID technology separates the certification process. Jeong, such as the claim that the proposed protocol for reuse attacks, spoofing attacks, prevent information disclosure and traceability fire safety, but raises issues of security and operations efficiency. Therefore, in this paper, Jeong, such as the security of the proposed protocol and to prove the computational efficiency issues, and to enhance the safety and efficiency of RFID technology based on practical u-Healthcare services authentication protocol is proposed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.6
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• pp.467-474
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• 2012

UAVs for reconnaissance and intelligence operations require long endurance capability, which demands high efficiency of the propulsion system. The distributed propulsion system(DPS) generates the thrust by replacing a large propulsion system with a number of small propulsion systems. A DPS distributed along the wing span can produce gains in propulsion efficiency by reducing ejection velocity. Also, the ingestion of boundary layers through the distributed DPS inlet and ejecting flow from the outlet can improve the lift to drag ratio of the vehicle. This study investigates the effects of locations and size of the inlet and outlet of the DPS on the blended-wing-body design based on Eppler 337 airfoil, with a CFD tool. The fans in the DPS are modeled as actuator disks for computational efficiency. The best location and aspect ratio of the inlet and outlet are found from lift-to-drag ratio and pitching moment considerations.

• Journal of the Korean Geotechnical Society
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• v.40 no.5
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• pp.21-37
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• 2024

Maximizing the efficiency of blasting operations is crucial for reducing project costs, shortening timelines, and minimizing environmental impacts-key factors for the success of large-scale marine reclamation projects. This study explores the application of pocket-charging methods, developed from mining principles, to enhance rock fragmentation efficiency in large-scale blasts. The aim is to optimize the material production process for marine reclamation construction. The pocket-charging technique efficiently disperses blasting energy, increasing the extent of rock fragmentation and thereby improving overall blasting performance. Even with minimal explosive quantities, optimal results and cost-efficient, expedited construction can be achieved. This research validates the effectiveness of pocket-charge blasting through blast simulation programs and outlines suitable blasting designs and strategies.

• Journal of the Korea Society of Computer and Information
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• v.29 no.8
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• pp.85-92
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• 2024

In this paper presents a comparative analysis of the performance between the latest object detection model, YOLOv10, and its previous versions. YOLOv10 introduces NMS-Free training, an enhanced model architecture, and an efficiency-centric design, resulting in outstanding performance. Experimental results using the COCO dataset demonstrate that YOLOv10-N maintains high accuracy of 39.5% and low latency of 1.84ms, despite having only 2.3M parameters and 6.7G floating-point operations (FLOPs). The key performance metrics used include the number of model parameters, FLOPs, average precision (AP), and latency. The analysis confirms the effectiveness of YOLOv10 as a real-time object detection model across various applications. Future research directions include testing on diverse datasets, further model optimization, and expanding application scenarios. These efforts aim to further enhance YOLOv10's versatility and efficiency.

• International Journal of Vascular Biomedical Engineering
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• v.2 no.1
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• pp.11-16
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• 2004

Both flow visualizations and computational fluid dynamics were performed to determine hemodynamics in a total cavopulmonary connection (TCPC) model for surgically correcting congenital heart defects. From magnetic resonance images, an anatomically correct glass model was fabricated to visualize steady flow. The total flow rates were 4, 6 and 8L/min and flow rates from SVC and IVC were 40:60. The flow split ratio between LPA and RPA was varied by 70:30, 60:40 and 50:50. A pressure-based finite-volume software was used to solve steady flow dynamics in TCPC models. Results showed that superior vena cava(SVC) and inferior vena cava(IVC) flow merged directly to the intra-atrial conduit, creating two large vortices. Significant swirl motions were observed in the intra-atrial conduit and pulmonary arteries. Flow collision or swirling flow resulted in energy loss in TCPC models. In addition, a large intra-atrial channel or a sharp bend in TCPC geometries could influence on energy losses. Energy conservation was efficient when flow rates in pulmonary branches were balanced. In order to increase energy efficiency in Fontan operations, it is necessary to remove a flow collision in the intra-atrial channel and a sharp bend in the pulmonary bifurcation.