• Geomechanics and Engineering
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• v.13 no.1
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• pp.141-159
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• 2017

A pick cutter is a rock-cutting tool used in partial-face excavation machines such as roadheaders, and its quality is a key element influencing the excavation performance and efficiency of such machines. In this study, pick cutters with hardfacing deposits applied to a tungsten carbide insert were made with aim of increasing their durability and wear resistance. They were field-tested by being installed in a roadheader and compared with conventional pick cutters under the same excavation conditions for 24 hours. The hardfaced pick cutters showed much smaller weight loss after excavation, and therefore better excavation performance, than the conventional pick cutters. In particular, the damage to and detachment (loss) of tungsten carbide inserts was minimal in the hardfaced pick cutters. A detailed inspection using scanning electron microscope-energy dispersive X-ray spectrometry and three-dimensional X-ray computed tomography scanning revealed no macro- or micro-cracks in the pick cutters. The reason for the absence of cracks may be that the heads of pick cutters are mechanically worn after the tungsten carbide inserts have been worn and damaged. However, scanning revealed the presence of voids between tungsten carbide inserts and pick cutter heads. This discovery of voids indicates the need to improve production processes in order to guarantee a higher quality of pick cutters.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.187-196
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• 2017

In using lecture evaluation methods to improve the quality of education, most universities need to reflect the changes in the educational environment. The transformation of university education into a mixed learning environment blending face-to-face education and online education necessitates the development of appropriate lecture evaluation items. For this purpose, we analyzed the items and the factor analysis for the students of C university in Daejeon. The primary data were carried out with 47 measurement items in 10 domains, such as planning and preparation of lectures, which were found through previous research analysis. Secondary data were validated by using the items confirmed through analysis of preliminary test data. The study results showed that 20 items including six domains such as planning and preparation of lectures, learning materials, learning tasks, instruction media, online course test and grades were derived. These study results suggest that universities lectures should be evaluated to ensure improvement.

• The Journal of Pediatrics of Korean Medicine
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• v.18 no.2
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• pp.127-142
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• 2004

Objective : To evaluate the effect of Oriental medical treatment on a patient with Ramsay Hunt syndrome with poor prognosis on EMG. Methods : We applied various methods of Oriental Medical treatment including Acupuncture, Electroacupuncture, Herb medicine, Vesiculation therapy using Mylabris and Crontonis Fructus, Massage, Self-excercise of face muscles. Results : 1. Herb medicine was applied on the basis of Differentiation of Syndromes(辨證): We tried Herb medicine to improve the function of Digestive System. The patient's stool condition, subjective sensation related with abdominal pain and general condition improved. 2. We used the Vesiculation therapy using Mylabris which was used traditionally to treat Facial Palsy. We powdered Mylabris and mixed it with Crontonis Fructus to make a paste. We put it on Ye-poong(?風), Nae-gwan(內關) at left side. It induced vesicles at the applied area, but it disappeared in 48 hours without any scar. 3. We applied acupuncture, electroacupunture, massage and self-excercise of face muscles. On gross scale assessment, there was some improvement. And assessment with regional scale also showed changes. The patient and the guardian were satisfied with the result. Conclusion : We experienced a case of Ramsay Hunt syndrome with poor prognosis on EMG. She also showed poor response to conservative treatment. Through various modalities of Oriental medical treatment, we attained some clinical improvement.

• The Journal of Information Systems
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• v.26 no.3
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• pp.119-147
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• 2017

Purpose In an online e-commerce environment without face-to-face contact between the seller and the buyer, the attitudes of consumers differ greatly depending on which framing strategy is applied, even in cases when the benefits of the deals represent the same value. The purpose of this study is to explore the effects of price-framing and message-framing strategies on consumer attitudes through an experimental analysis in the context of online travel product purchasing. This study suggests a research model based on prospect theory and prior literature on price-framing and message-framing strategies. Design/methodology/approach The experiment was structured as a 2 (discount price presentation: 'Won' vs. '%') ${\times}$ 2 (discount level: low vs. high) ${\times}$ 2 (time-limit message: none vs. one) mixed design. The research hypotheses were tested in a study of 200 undergraduate and graduate students assigned randomly and distributed evenly to each of the eight cells. Findings The findings indicate that consumer attitudes become more favorable when the '%' discount, higher discount rate, and time-limit message are presented. However, no significant interaction effect is found between the discount price presentation and the discount level/time-limit message. This study has a theoretical implication in that it extends the scope of research by examining the influence of framing strategies on experience goods such as online travel products. Moreover, this study can provide managers with more specific guidelines when establishing framing strategies in the context of purchasing online travel products.

• The Journal of Korean Institute of Information Technology
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• v.16 no.11
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• pp.105-113
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• 2018

In this paper, we proposed a method for effective classification of eye, nose, and mouth of human face. Most recent image classification uses Convolutional Neural Network(CNN). However, the features extracted by CNN are not sufficient and the classification effect is not too high. We proposed a new algorithm to improve the classification effect. The proposed method can be roughly divided into three parts. First, the Haar feature extraction algorithm is used to construct the eye, nose, and mouth dataset of face. The second, the model extracts CNN features of image using AlexNet. Finally, Haar-CNN features are extracted by performing convolution after Haar feature extraction. After that, CNN features and Haar-CNN features are fused and classify images using softmax. Recognition rate using mixed features could be increased about 4% than CNN feature. Experiments have demonstrated the performance of the proposed algorithm.

• Safety and Health at Work
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• v.13 no.3
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• pp.364-371
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• 2022

Background: Respiratory masks can provide healthcare workers with protection from biological hazards when they have good performance. There is a direct relationship between the visual specifications of a mask and its efficacy; thus, the aim of this study was to develop tools for qualitative assessment of the performance of masks used by healthcare workers. Methods: A mixed-methods design was used to develop a qualitative assessment tool for medical face masks (MFM) and particle filtering half masks (PFHM). The development of domains and items was undertaken using observation and interviews, the opinions of an expert panel, and a review of texts and international standards. The second phase evaluated the psychometric properties of tools. Finally, the validated Mask Qualitative Assessment Tools (MQAT) were used to assess six samples from 10 brands of the two types of masks. Results: MQAT-MFM and MQAT-PHFM shared 42 items across seven domains: "cleanliness," "design," "marking, labeling and packaging," "mask layers," "mask strap," "materials and construction," and "nose clip." MQAT-MFM included one additional item. MQAT-PHFM included another nine items associated with an eighth "Practical Performance" domain, and the valve version had another additional "Exhalation Valve" domain and six items. The evaluation indicated 80% compliance for MFM and 71% compliance for PFHM. "Marking, labeling and packaging" and "Layers" were associated with the least compliance in both types of masks and should be checked carefully for defining mask quality. Conclusion: MQAT can be used for immediate screening and initial assessment of MFM and PHFM through appearance, simple tools, and visual inspection.

• Educational Technology International
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• v.13 no.2
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• pp.257-281
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• 2012

This study aims to examine individual perceptions and lived experiences of the Net generation of student teachers and the previous generation of teachers about their technology use in education. The participants of this study include 106 pre-service teachers and 50 in-service teachers from one teacher education university in Korea. Employing a mixed methodology, we first empirically examined the participants' perceptions toward multiple variables related to technology use in education, namely (a) past ICT experiences in schools, (b) personal computer use, (c) constructivist belief, (d) computer efficacy, (e) attitude toward computer in education, and (f) prospective computer use. In addition, we conducted face-to-face interviews with selected participants for the in-depth investigation of their lived experiences about technology use, beliefs, and attitude. Results indicate that there are significant differences between in-service and pre-service teachers in their prior experiences with technology in schools. However, the pre-service and in-service teachers did not differ significantly in their beliefs, attitude and other technology-related variables, which may indicate the danger of generational determinism in the Net Generation debate. The analysis of interview narratives revealed two major themes about the interplay of one's agency and structural changes in the participants' lived experiences with technology use in education: (a) transition from negative past experiences to opportunities for positive computer use, and (b) attitudes formation and change through apprenticeship experiences and structural influences. In conclusion, this study suggests that the Net Generation debate should move beyond dichotomous or techno-centric thinking. There is a critical need to pay more attention to develop deeper understandings of the fundamental diversity existing within the generation itself. Implications for teacher education are also discussed.

• Journal of Veterinary Clinics
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• v.40 no.5
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• pp.382-386
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• 2023

A 2-year-old, 12.5 kg, castrated male, mixed-breed dog was presented with a 1-year history of pruritus and progressive alopecia. On physical examination, no remarkable findings were detected including body condition score (5/9). A dermatological examination of the dog revealed generalized erythema, papules or plaques, especially on the face, auricle, dorsum, and shoulder. A fine-needle aspiration of the dorsum and face lesions revealed various numbers of macrophages with foamy cytoplasm and multinucleated giant cells. A bacterial culture test showed the growth of Staphylococcus pseudintermedius. A complete blood cell count was unremarkable and biochemical abnormalities included hyperglobulinemia (4.8 g/dL, reference interval 2.5-4.5 g/dL), mild hypertriglyceridemia (277 mg/dL, reference interval 10-100 mg/dL) and mild hypercholesterolemia (383 mg/dL, reference interval 110-320 mg/dL). Additional diagnostic tests were performed to identify the underlying cause of hyperlipidemia. Canine pancreatic lipase immunoreactivity (<50 ng/mL, reference interval 0-200 ng/mL) and total T4 (1.4 ㎍/dL, reference interval 1.1-5.6 ㎍/dL) were within the reference intervals. For a definitive diagnosis, skin biopsy specimen was collected from the papular lesions on the dorsum by using a 4 mm biopsy punch. A histopathological examination revealed numerous large macrophages with abundant foamy cytoplasm in the dermis. The foamy macrophages were located diffusely between the collagen fibers. Extracellular amorphous lipid deposits were also presented in the dermal tissue. A definitive diagnosis of cutaneous xanthoma was made based on clinical signs and cytological and histopathological results.

• Industrial Engineering and Management Systems
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• v.11 no.2
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• pp.155-164
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• 2012

As the global market becomes more competitive, manufacturing industries face relentless pressure caused by a growing tendency of greater varieties of products, shorter manufacturing cycles and more sophisticated customer requirements. Efficient and effective supplier selection and order allocation decisions are, therefore, important decisions for a manufacturer to ensure stable material flows in a highly competitive supply chain, in particular, when customers are willing to accept products with less desirable product attributes (e.g., color, delivery date) for economic reasons. This paper attempts to solve optimally the challenging problem of supplier selection and order allocation, taking into consideration the customer flexibility for a manufacturer producing multi-products to satisfy the customers' demands in a multi period planning horizon. A new mixed integer programming model is developed to describe the behavior of the supply chain. The objective is to maximize the manufacturer's total profit subject to various operating constraints of the supply chain. Due to the complexity and non-deterministic polynomial-time (NP)-hard nature of the problem, an improved genetic approach is proposed to solve the problem optimally. This approach differs from a canonical genetic algorithm in three aspects: a new selection method to reduce the chance of premature convergence and two problem-specific repair heuristics to guarantee feasibility of the solutions. The results of applying the proposed approach to solve a set of randomly generated test problems clearly demonstrate its excellent performance. When compared with applying the canonical genetic algorithm to locate optimal solutions, the average improvement in the solution quality amounts to as high as ten percent.

• Journal of the Korea Furniture Society
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• v.19 no.6
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• pp.475-486
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• 2008

In this study, fire-retardant chemicals were melt with mixed composition ratios of dibasic ammonium phosphate and each half of boric acid and borax in hot water, in which hammer-milled chips were immersed to increase swelling of waste particleboards. Also, fire-retardant treated particles from sawn lumber chip and recycled particleboard chip were composed in ratio of 70:30 in core layer to improve boards' properties. Retention ratio of fire-retardant chemicals for the particles for face layer was high due to high specific surface area, and that of sawn lumber chips was somewhat higher than that of recycled particleboard chips. The mixture of particles from sawn lumber chips and recycled PB of 70:30 in weight ratio exceeded bending strength of 100 $kgf/cm^2$. It seemed that the relatively greater portions of dibasic ammonium phosphate affected adversely to dimensional stability, however fire-retardants treatment resulted in distinct effect lowering formaldehyde emission such as $E_0$ type(0.5mg/$\ell$ or less) in KS F 3104. In fire-retardancy, the recycled boards with a mixed ratio of dibasic ammonium phosphate to boric acid borax(50:50 mixture) of 70% to 30% in weight satisfied fire-retardancy 3rd grade in KS F 2271, and also this composition from cone calorimeter test met same standard grade figuring total heat release of 4.6MJ/$m^2$.