Search results

1 – 5 of 5
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 10 June 2020

Taehun Kim, Guk Bae Kim, Hyun Kyung Song, Yoon Soo Kyung, Choung-Soo Kim and Namkug Kim

This study aims to systemically evaluate morphological printing errors between computer-aided design (CAD) and reference models fabricated using two different three-dimensional…

208

Abstract

Purpose

This study aims to systemically evaluate morphological printing errors between computer-aided design (CAD) and reference models fabricated using two different three-dimensional printing (3DP) technologies with hard and soft materials.

Design/methodology/approach

The reference models were designed to ensure simpler and more accurate measurements than those obtained from actual kidney simulators. Three reference models, i.e. cube, dumbbell and simplified kidney, were manufactured using photopolymer jetting (PolyJet) with soft and hard materials and multi-jet printing (MJP) with hard materials. Each reference model was repeatably measured five times using digital calipers for each length. These values were compared with those obtained using CAD.

Findings

The results demonstrate that the cube models with the hard material of MJP and hard and soft materials of PolyJet were smaller (p = 0.022, 0.015 and 0.057, respectively). The dumbbell model with the hard material of MJP was smaller (p = 0.029) and that with the soft material of PolyJet was larger (p = 0.020). However, the dumbbell with the hard material of PolyJet generated low errors (p = 0.065). Finally, the simplified kidney models with the hard material of MJP and soft materials of PolyJet were smaller (p = 0.093 and 0.021) and that with the hard material of PolyJet was opposite to the former models (p = 0.043).

Originality/value

This study, to the best of authors’ knowledge, is the first to determine the accuracy between CAD and reference models fabricated using two different 3DP technologies with multi-materials. Thus, it serves references for surgical applications as simulators and guides that require accuracy.

Details

Rapid Prototyping Journal, vol. 26 no. 7
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 25 June 2020

Jaeyoung Kwon, Guk Bae Kim, Sunah Kang, Younghwa Byeon, Ho-Seok Sa and Namkug Kim

Extrinsic trauma to the orbit may cause a blowout or orbital fracture, which often requires surgery for reconstruction of the orbit and repositioning of the eyeball with an…

154

Abstract

Purpose

Extrinsic trauma to the orbit may cause a blowout or orbital fracture, which often requires surgery for reconstruction of the orbit and repositioning of the eyeball with an implant. Post-operative complications, however, are high with the most frequent cause of complications being a mismatch of the position and shape of the implant and fracture. These mismatches may be reduced by computed tomography (CT) based modeling and three-dimensional (3D) printed guide. Therefore, the aim of this study is to propose and evaluate a patient-specific guide to shape an orbital implant using 3D printing.

Design/methodology/approach

Using CT images of a patient, an orbital fracture can be modeled to design an implant guide for positioning and shaping of the surface and boundaries of the implant. The guide was manufactured using UV curable plastic at 0.032 mm resolution by a 3D printer. The accuracy of this method was evaluated by micro-CT scanning of the surgical guides and shaping implants.

Findings

The length and depth of the 3D model, press-compressed and decompressed implants were compared. The mean differences in length were 0.67 ± 0.38 mm, 0.63 ± 0.28 mm and 0.10 ± 0.10 mm, and the mean differences in depth were 0.64 ± 0.37 mm, 1.22 ± 0.56 mm and 0.57 ± 0.23 mm, respectively. Statistical evaluation was performed with a Bland-Altman plot.

Originality/value

This study suggests a patient-specific guide to shape an orbital implant using 3D printing and evaluate the guiding accuracy of the implant versus the planned model.

Details

Rapid Prototyping Journal, vol. 26 no. 8
Type: Research Article
ISSN: 1355-2546

Keywords

Available. Open Access. Open Access
Article
Publication date: 10 October 2024

Ji-Myong Kim, Sang-Guk Yum, Manik Das Adhikari and Junseo Bae

This study proposes a deep learning algorithm-based model to predict the repair and maintenance costs of apartment buildings, by collecting repair and maintenance cost data that…

253

Abstract

Purpose

This study proposes a deep learning algorithm-based model to predict the repair and maintenance costs of apartment buildings, by collecting repair and maintenance cost data that were incurred in an actual apartment complex. More specifically, a long short-term memory (LSTM) algorithm was adopted to develop the prediction model, while the robustness of the model was verified by recurrent neural networks (RNN) and gated recurrent units (GRU) models.

Design/methodology/approach

Repair and maintenance cost data incurred in actual apartment complexes is collected, along with various input variables, such as repair and maintenance timing (calendar year), usage types, building ages, temperature, precipitation, wind speed, humidity and solar radiation. Then, the LSTM algorithm is employed to predict the costs, while two other learning models (RNN and GRU) are taught to validate the robustness of the LSTM model based on R-squared values, mean absolute errors and root mean square errors.

Findings

The LSTM model’s learning is more accurate and reliable to predict repair and maintenance costs of apartment complex, compared to the RNN and GRU models’ learning performance. The proposed model provides a valuable tool that can contribute to mitigating financial management risks and reducing losses in forthcoming apartment construction projects.

Originality/value

Gathering a real-world high-quality data set of apartment’s repair and maintenance costs, this study provides a highly reliable prediction model that can respond to various scenarios to help apartment complex managers plan resources more efficiently, and manage the budget required for repair and maintenance more effectively.

Details

Engineering, Construction and Architectural Management, vol. 31 no. 13
Type: Research Article
ISSN: 0969-9988

Keywords

Access Restricted. View access options
Article
Publication date: 1 November 1997

John Lie

From 1953 to 1961, the South Korean economy grew slowly; the average per capita GNP growth was a mere percent, amounting to less than $100 in 1961. Few people, therefore, look for…

463

Abstract

From 1953 to 1961, the South Korean economy grew slowly; the average per capita GNP growth was a mere percent, amounting to less than $100 in 1961. Few people, therefore, look for the sources of later dynamism in this period. As Kyung Cho Chung (1956:225) wrote in the mid‐1950s: “[South Korea] faces grave economic difficulties. The limitations imposed by the Japanese have been succeeded by the division of the country, the general destruction incurred by the Korean War, and the attendant dislocation of the population, which has further disorganized the economy” (see also McCune 1956:191–192). T.R. Fehrenbach (1963:37), in his widely read book on the Korean War, prognosticated: “By themselves, the two halves [of Korea] might possibly build a viable economy by the year 2000, certainly not sooner.”

Details

International Journal of Sociology and Social Policy, vol. 17 no. 11/12
Type: Research Article
ISSN: 0144-333X

Access Restricted. View access options
Book part
Publication date: 28 August 2015

Jose Guerra Vio

This chapter focuses on South Korea’s newly found regional leadership, as the emergent middle power of East Asia, in order to advance regional integration and…

Abstract

This chapter focuses on South Korea’s newly found regional leadership, as the emergent middle power of East Asia, in order to advance regional integration and institution-building. Policy leadership is observed and analyzed from an international lens, linked to the literature of middle powers. The chapter first conceptualizes middle powers in connection with the issue of international leadership, since such states often play important roles in promoting cooperation. The chapter looks especially into South Korea’s foreign policy behavior toward East Asian regional processes and how it has manifested innovative and capable leadership. More specifically, the last three presidencies of Kim Dae-jung (1998–2002), Roh Moo-hyun (2003–2008), and Lee Myung-bak (2008–2013) are scrutinized in the hope of underscoring how their particular administrations, political leadership, and strategic approaches to foreign policy toward the region influenced South Korea’s regional leadership attempts and middle power status.

Details

Asian Leadership in Policy and Governance
Type: Book
ISBN: 978-1-78441-883-0

Keywords

1 – 5 of 5
Per page
102050