http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Nguyen Cong Hong Phong,Kim Youngdoo,Do Quang Thang,Choi Young 한국CDE학회 2021 Journal of computational design and engineering Vol.8 No.3
Additive manufacturing has enabled the fabrication of complex structures such as cellular structures. Although numerous design frameworks have been proposed for cellular structures, their effectiveness was limited owing to the use of B-rep-based representation. To address the limitations in previous research, this study proposes an implicit-based computer-aided design framework customized for additively manufactured functionally graded cellular structures (AM-FGCSs). The proposed design framework effectively aids in both single- and multiscale structural optimization for designing FGCSs. Moreover, implicit-based modeling afforded a reliable geometric representation that could efficiently assist computation tasks such as visualization, validation, and process planning for fabrication. In addition, two case studies were conducted to demonstrate the effectiveness of the proposed framework for designing FGCSs. The first case study on a three-point bending beam design problem proved the practicality of implicit-based representation in multiscale structural design. Meanwhile, the second case study validated the proficiency of the proposed framework in process planning for fabrication and engineering analysis, the two most vital computation tasks in designing cellular structures.
Nguyen, Cong Hong Phong,Choi, Young Elsevier 2018 AUTOMATION IN CONSTRUCTION - Vol.91 No.-
<P><B>Abstract</B></P> <P>Inspection is vital in industrial plant construction and management. However, traditional inspection methods that rely on human involvement and paper documentation are becoming untenable as modern industrial plants are becoming larger and more complex than legacy facilities. Hence, an efficient and robust method is required to support the inspection of modern industrial plants. In this paper, an improved technique relying on terrestrial laser scanning (TLS) for data acquisition and normal-based region growing and efficient random sample consensus (RANSAC) for point cloud data processing is proposed for the on-site dimensional inspection of the piping systems of an industrial plant. Consequently, the as-built condition of the plant is assessed via a distance-based deviation analysis and a comparison of geometric parameters between the as-designed and as-built models. The method is validated using a dataset acquired from a compartment of a ship has verified the robustness and reliability of the proposed approach.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Point cloud data and 3D CAD data comparison for on-site dimensional inspection. </LI> <LI> Normal-based region growing and efficient RANSAC for point cloud processing. </LI> <LI> As-built dimensional condition verification with distance-based deviation analysis and geometric parameter comparison. </LI> </UL> </P>
Lightweight design with metallic additively manufactured cellular structures
Nguyen Phong Cong Hong,Kim Youngdoo,Choi Young 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.1
Lightweight design is essential in modern product development and is prevalent in automotive, aerospace, and biomedical applications. The utilization of cellular structure, aided by advancements in additive manufacturing, is among the most effective methods for achieving lightweight design without sacrificing structural integrity and functionality. In this paper, a stress-based structural optimization method is proposed for the design of lightweight components filled with octet functionally graded cellular structures fabricated using selective laser melting (SLM) with the AlSi10Mg alloy. The proposed method includes two main parts: the homogenization-based characterization of SLM-octet-cellular structures and the utilization of the characterized cellular structures for lightweight structure optimum design. Tensile and compression experiments were utilized to validate the proposed homogenization-based characterization method, showing that the simulation and experimental results were in agreement. In addition, the effectiveness of the proposed design optimization method was validated using the three-point bending beam design problem. The experimental results revealed that components filled with functionally graded cellular structures can withstand 15.25$\%$ more load than those with uniform cellular structures. This investigation presents a complete, validated, and industry-oriented lightweight design method, which is useful for the development of future green products.
NGUYEN, Ha Hong,NGUYEN, Trung Thanh,NGUYEN, Phong Thanh Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.1
The study aims to identify the factors affecting employee loyalty in the case of small and medium enterprises (SMEs) in Tra Vinh province, Viet Nam and to find out critical factors affecting the loyalty of employees in SMEs. This is implemented with the method of collecting primary data of 320 employees working at SMEs in 5 districts including: Cau Ngang, Tra Cu, Chau Thanh, Cang Long, Tieu Can) and Tra Vinh City, Viet Nam. Using the multivariate regression method, the researchers have found 6 factors affecting employee loyalty: colleagues, leaders, job characteristics, remuneration policies, organizational culture, and working environment. Particularly, learning opportunities may not be not statistically significant for employees' loyalty towards small and medium-sized enterprises in Tra Vinh province. From the above research results, the authors have proposed implicational piolicies such as: focusing on colleague relationships, improving leadership of business owners, attaching importance to appropriate work arrangement, having appropriate remuneration policies for laborers, building effective organizational culture and working environment to improve employee loyalty at SMEs. From the above policy implications, helping business owners realize the aspirations of workers in small and medium-sized enterprises more closely in the future, in order to sustainably develop the business system in Vietnam.
Protective Effect of Composted Spent Mushroom Substrate (Hericium Erinaceus) on Phytophthora Capsici
응웬홍파옹 ( Nguyen Hong Phong ),강희완 ( Hee-wan Kang ) 한국농공학회 2020 한국농공학회 학술대회초록집 Vol.2020 No.-
Understanding crop water requirements (CWR) is essential for the better irrigation practices. Scheduling and efficient use of water since the water supply through rainfall is limited. The main objectives of the research were estimated crop water requirement and irrigation scheduling for rice crops, in addition, to increase agricultural productivity and improving irrigation efficiency uses. The irrigation schedules and water requirements were simulated using CROPWAT, and the model result was verified with field values in the Maliana Irrigation Scheme, Bobonaro District of East Timor. The results indicated the wider applicability of CROPWAT in calculating water requirement as well as developing irrigation schedules for rice irrespective of the agro-climate conditions. The specific objectives were (i) to estimate reference evapotranspiration (Eto), (ii) to an estimate of the effective rainfall from the Maliana stations, (iii) to estimate of crop water requirements for rice crops, (iv) to estimate irrigation schedule. The average value of reference evapotranspiration of the crop was 4.98mm/day. It ranges from 4.21mm/day to 5.90mm/day. The maximum evapotranspiration of crop was accorded in the month of September and the minimum were January. The maximum effective rainfall of 155. 2mm in the month of January and a minimum of 5.3mm during August. The total irrigation water requirement for the rice crop the season from December to April was 435.3mm. This low water requirement for rice is mainly due to higher effective rainfall in the site of study. The net irrigation applied to the field varies from 90mm to107.8mm with an average net irrigation of 486.9mm. The gross irrigation water requirement ranges from 128.57mm to 154mm with average gross irrigation water of 695. 6mm.
Cong Hong Phong Nguyen,Youngdoo Kim,Young Choi 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.1
Lattice structures are well-known as a solution for designing parts with lightweight and multifunctional characteristics. Owing to the advancement of additive manufacturing (AM), the development of design methods for additively manufactured lattice structures has extensively progressed, especially for functionally graded lattice structures (FGLS). Despite plenty of available design frameworks, the application of AM constraints in the design of FGLS is limited to geometric issues. Further, there is a lack of design methods that consider the unique physical properties of additively manufactured parts, especially the anisotropic characteristics induced by AM processes. This paper proposes a novel method for the design of additively manufactured functionally graded lattice structures with the consideration of AM anisotropic properties. In addition, a customized anisotropic AM-Lattice material model that supports the design of FGLS through the density-variable topology optimization is proposed. Moreover, Fused Deposition Modeling (FDM) process in which the process-induced anisotropy of AM is clearly demonstrated is focused. The design method was validated by the three-point bending-beam design problem, a classical design problem for validating topology optimization. The results, showing agreements between simulations and experiments, prove the validity and practicality of the proposed method.