• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.1266-1269
• /
• 2003

Many studies have indicated that most of a product's cost is fixed early in its lift cycle, before the original design cycle is complete. This implies that we should consider various aspects of product lift cycle at the design stage. This means the need of collaboration in design stage. Because the Internet provides instant access to a wealth of design information, the Internet is used by the collaborative design team members as a medium to share data, information and knowledge, and in some cases for product data management and project management by integrating the Web with appropriate technologies. This paper presents a real-time collaborative design system for powerful interaction performance, based on the Internet and Web technologies. Using The system use the client/server architecture and the purpose of the system is to provide a method that enables real-time view, review and modification of the 3D model through the Internet.

• Tunnel and Underground Space
• /
• v.27 no.2
• /
• pp.69-76
• /
• 2017

Physical models of underground mines are very useful to the design of mine openings and the management of work progress of mining companies as well as to consulting. Even though 3D image realization techniques for mine openings have already been developed by various companies the physical models are still widely used because they can provide better understanding without sophisticated equipments for the most of people. Conventional materials for the physical models are paper and acryl which demand a lot of time and labor to make the model even with low precision and high cost. In this research, 3D printing technique is adopted to develop the physical model with relatively short time, low cost, and proper degree of precision. Finally the computer software "UMine2STL" was developed and verified by comparing the printed product with its design.

• The Journal of the Convergence on Culture Technology
• /
• v.4 no.1
• /
• pp.331-335
• /
• 2018

A pillow was fabricated through CAE(Computer Aided Engineering) and 3D printing, which can adjust automatically the height of the pillow when lying sideways and backwards according to the sleeping posture. The target height difference of the pillow was about 1.0 cm ~ 1.5 cm when the head weight difference was about 1.2 kg. Instead of using a complex mechanical device, it was based on an arch structure made of TPU. From the simulation, the optimum model was designed through series combination and the results were compared with the experimental ones. The final product had a height difference of about 2 cm according to the lying posture.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.17 no.5
• /
• pp.117-122
• /
• 2018

3D printing technology and its applications have grown rapidly in academia and industry. We consider a 3D printing system designed for the selective laser sintering (SLS) method, which is one of the powder bed fusion (PBF) techniques to build up the final product by layering sintered powder slices. Thermal distortion of printing products is a critical challenge in 3D printing. This study investigates temperature-dependent conformational behaviors of 3D printed samples of sintered poly-ether-ether-ketone (PEEK) powders using molecular dynamics simulations. The wear and chemical resistance properties of PEEK are understood, as it is a well-known biocompatible material used for implants. However, studies on physical phenomena at nanoscale in PEEK are rarely published in public. We simulate dissipative particle dynamics to elucidate how a cavity regime forms in PEEK at different system temperatures. We demonstrate how PEEK structures deform subject to the system temperature distribution.

• Natural Product Sciences
• /
• v.14 no.1
• /
• pp.56-61
• /
• 2008

Bioactivity guided phytochemical study of the petroleum ether and butanol extracts of Clematis hirsuta resulted in the isolation of 12 compounds. Rat paw edema as a model of acute inflammation was used to evaluate the anti-inflammatory activity of the extracts and the chromatographic fractions. Five known sterols and triterpenes namely: ${\beta}-amyrin$ (1), lupeol (2), ${\beta}-sitosterol$ (3), oleanolic acid (4) and stigmasterol glycoside (5) were isolated from the petroleum ether extract. The n-butanol extract afforded two compounds reported for the first time from natural source: (S)-(+)-dihydro-5-(hydroxymethyl)-2(3H)-furanone (7) and (s)-(-)-5-hydroxymethyl-2(5H)-furanone (8). In addition, anemonin (6), dihydro-4-hydroxy-5-(hydroxymethyl)-2(3H)-furanone (2-deoxy-D-ribono-1,4-lactone) (9), biophenol (cimidahurin) (10), glucose (11) and sucrose (12) were also identified. The structures were determined from spectroscopic data including 1D- and 2D-NMR experiments.

• Journal of Distribution Science
• /
• v.13 no.3
• /
• pp.79-91
• /
• 2015

Purpose - First, the study identifies and analyzes consumer preferences with regard to health foods and supplements. Second, it identifies and analyzes consumer preferences with regard to the properties of Vitamin C supplements. Third, in order to provide a basic data for the development of Vitamin C supplements and to measure how consumers value the properties of different Vitamin C products, a consumer survey was conducted through the choice-based conjoint model. Based on the results, the research estimates consumers' relative product-related priorities as well as price levels and willingness to pay (WTP) for different product types, and makes suggestions regarding consumer-oriented new product development and progressive directions for the successful launch of health foods and supplements. Research design, data, and methodology - This study aims to define the attributes of health foods and supplements based on several characteristics including their natural ingredients, product price, product originality, natural ingredient content, and additional functional ingredients, and makes suggestions regarding strategic market pricing and product development for health foods and supplements according to customer attitudes and characteristics. The research used choice-based conjoint analysis methodology based on the Multinomial Logic Model and collected 94 questionnaires filled out by users of Korean Vitamin C supplements. Results - Product price is the most influential factor among the five analyzed properties. When consumers buy Vitamin C products, the relative significance level of four of the examined properties is as follows: 40.9% for product price, 23.3% for product originality, 21.9% for natural ingredient content, and 13.9% for additional functional ingredients. Vitamin C content is excluded as it is not a statistically significant factor. It is interesting that supplement manufacturers and retailers consider Vitamin C content to be very important whereas consumers do not regard it as an important factor at the time of purchase. The results for the marginal willingness to pay (MWTP) for each property of Vitamin C supplements show that consumers are willing to pay an additional 11,146 Korean won for a 50% increase in the natural ingredient content. With regard to product originality, consumers are willing to pay an additional 11,301 Korean won for products manufactured in Europe than for products manufactured in China. Moreover, consumers show a greater preference for products manufactured in Korea than in Europe. However, consumers are not willing to pay more for additional Vitamin C or additional functional ingredients added to Vitamin C products. Conclusions - According to the results of consumer research on Vitamin C supplements, which represent a popular health food supplement in Korea, most Korean health food and supplement companies are not consumer- or market-oriented when developing new products. Companies gather information from either R&D specialists or sales managers and their opinions are highly reflected in new product development. The study's results will help companies recognize the importance of understanding consumers' unmet needs in advance to develop new products in the future.

• Journal of Korea Technology Innovation Society
• /
• v.9 no.2
• /
• pp.350-372
• /
• 2006

The main purpose of this study is to investigate the technology related facts which determine the difference of the output of companies in the fields of IT and BT industries in Korean. The determining facts consist of the technology development strategy, the characteristic of R&D groups, and the ability of managing knowledge assets. Three kinds of regression model are made by using 3 determining facts from total model to IT and BT model to investigate the research purpose of this study. The technology development strategy consists of 2 sub facts, as technology innovation and product upgrade. The characteristic of R&D group consists of 2 sub facts, as the characteristic of task and the intensity of R&D group members. The ability of managing knowledge assets consist of 3 sub elements, as the ability of creating knowledge assets, the ability of holding in common knowledge assets, and the ability of developing the value of knowledge assets.

• Journal of Fashion Business
• /
• v.23 no.3
• /
• pp.67-84
• /
• 2019

Since the early 2000s, various fashion design products that use 3D printing technology have constantly been introduced to the fashion industry. However, given the nature of 3D printing technology, the flexible characteristics of material of textile fabrics is yet to be achieved. The aim of this study is to develop the optimal design conditions for production of flexible and elastic 3D printing fabric structure based on plain weave, which is the basic structure in fabric weaving using SLS 3D printing technology. As a the result this study aims to utilize appropriate design conditions as basic data for future study of flexible fashion product design such as textile material. Weaving structural design using 3D printing is based on the basic plain weave, and the warp & weft thickness of 4mm, 3mm, 2mm, 1.5mm, 1mm, and 0.7mm as expressed in Rhino 6.0 CAD software program for making a 3D model of size $1800mm{\times}180mm$ each. The completed 3D digital design work was then applied to the EOS SLS Machine through Maker ware, a program for 3D printer output, using polyamide 12 material which has a rigid durability strength, and the final results obtained through bending flexibility tests. In conclusion, when designing the fabric structure design in 3D printing using SLS method through application of polyamide 12 material, the thickness of 1 mm presented the optimal condition in order to design a durable digital textile structure with flexibility and elasticity of the 3D printing result.

• Journal of Applied Reliability
• /
• v.14 no.4
• /
• pp.225-229
• /
• 2014

A one-shot device is defined as a product, system, weapon, or equipment that can be used only once. After use, the device is destroyed or must undergo extensive rebuild. Determining the reliability of a one-shot device poses a unique challenge to the manufacturers and users due to the destructive nature and costs of the testing. This paper presents a reliability growth prediction for a one-shot system. It is assumed that 1) test duration is discrete(i.e. trials or rounds); 2) trials are statistically independent; 3) the number of failures for a given system configuration is distributed according to a binomial distribution; and 4) the cumulative expected number of failures through any sequence of configurations is given by AMSAA model. When the system development is represented by three configurations and the number of trials and failures during configurations are given, the AMSAA model parameters and reliability at configuration 3 are estimated by using a reliability growth analysis software. Further, if the reliability growth predictions do not meet the target reliability, the sample size of an additional test is determined for achieving the target reliability.

• Korean Journal of Computational Design and Engineering
• /
• v.19 no.4
• /
• pp.434-442
• /
• 2014

Most manufacturing enterprises create CAD data as a result of the product/part design process; however, the CAD data is being utilized only for production activities. Besides the processes directly related to manufacturing such as design and production, the CAD data is an important resource that can be used in variety of services (e.g., catalog production and production manuals) for manufacturing enterprises. This study proposes a software platform that can support a wide range of services for manufacturing companies in an efficient and productive way. The software platform was designed based on the functions identified by requirement analysis. The platform consists of four layers: data model layer to manage relevant data; library layer and common function layer to configure services; and application layer to install and run the software. Finally, this study evaluates the validity of the proposed platform architecture by applying it to the digital catalog system.