• Carbon letters
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• v.23
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• pp.1-8
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• 2017

Polycrystalline diamond (PCD) tools possessing high hardness and abrasive wear resistance are particularly suited for drilling of carbon fiber reinforced plastic (CFRP) composites, where tool life and consistent hole quality are important. While PCD presents superior performance when drilling CFRP, it is unclear how it performs when drilling multi-stack materials such as CFRP-titanium (Ti) stacks. This comparative study aims to investigate drilling of a Ti plate stacked on a CFRP panel when using PCD tools. The first sequence of the drilling experiments was to drill 20 holes in CFRP only. CFRP-Ti stacks were then drilled for the next 20 holes with the same drill bit. CFRP holes and CFRP-Ti stack holes were evaluated in terms of machined hole quality. The main tool wear mechanism of PCD drills is micro-fractures that occur when machining the Ti plate of the stack. Tool wear increases the instability and the operation temperature when machining the Ti plate. This results in high drilling forces, large hole diameter errors, high surface roughness, wider CFRP exit thermal damage, and taller exit Ti burrs.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.9
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• pp.1499-1507
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• 2003

Physical importance of cutting temperatures has long been recognized. Cutting temperatures have strongly influenced both the tool life and the metallurgical state of machined surfaces. Temperatures in drilling processes are particularly important, because chips remain in contact with the tool for a relatively long time in a hole. Tool temperatures tend to be higher in drilling processes than in other in machining processes. This paper concerns with modeling of thermal behaviors in drilling processes as well as estimation of the cutting temperature distribution based on remote temperature measurements. One- and two-dimensional estimation problems are proposed to analyze drilling temperatures. The proposed thermal models are compared with solutions of finite element methods. Observer algorithms are developed to solve inverse heat conduction problems. In order to apply the estimation of cutting temperatures, approximation methods are proposed by using the solution of the finite element method. In two-dimensional analysis, a moving heat source according to feedrate of the drilling process is regarded as a fixed heat source with respect to the drilling location. Simulation results confirm the application of the proposed methods.

• Korean Institute of Interior Design Journal
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• v.15 no.3 s.56
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• pp.184-192
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• 2006

On this study, we are focusing on the spatial value of the flagship store as an effective way of experiential communication for a brand. The purpose of this study is to create effective methods for the spatial identity by connecting significance of experiential communication and strategic factors of experiential marketing. The process of this research is summarized as follows: First, we select some cases of the flagship stores realizing differentiated methods of experiential marketing and classify the types according to the marketing strategy. Second, we can analyze each function in the context of social, cultural life style. Finally, for the company flagship stores can be a tool to construct a sustainable brand image and tool differentiation, and at the same time for the consumer they can create relationships through customers' experience in the space expressing brand identity and style. Also, flagship stores can be valued as a place offering emotional experiences of cultural consumption as well as product consumption when planned given the style suitable for brand image and strategies.

• Journal of Information Processing Systems
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• v.17 no.5
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• pp.972-988
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• 2021

At present, DevOps environments are getting popular in software organizations due to better collaboration and software productivity over traditional software process models. Software artefacts in DevOps environments are vulnerable to frequent changes at any phase of the software development life cycle that create a continuous integration continuous delivery pipeline. Therefore, software artefact traceability management is challenging in DevOps environments due to the continual artefact changes; often it makes the artefacts to be inconsistent. The existing software traceability related research shows limitations such as being limited to few types of artefacts, lack of automation and inability to cope with continuous integrations. This paper attempts to overcome those challenges by providing traceability support for heterogeneous artefacts in DevOps environments using a prototype named SAT-Analyser. The novel contribution of this work is the proposed traceability process model consists of artefact change detection, change impact analysis, and change propagation. Moreover, this tool provides multi-user accessibility and is integrated with a prominent DevOps tool stack to enable collaborations. The case study analysis has shown high accuracy in SAT-Analyser generated results and have obtained positive feedback from industry DevOps practitioners for its efficacy.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.4
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• pp.61-69
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• 2022

The function of coolant in machining is to reduce the frictional force in the contact area in between the tool and the material, and to increase the precision by cooling the work-piece and the tool, to make the machining surface uniform, and to extend the tool life. However, cutting oil is harmful to the human body because it uses chlorine-based extreme pressure additives to cause environmental pollutants. In this study, the effect of cutting temperature and surface roughness of titanium alloy for medical purpose (Ti-6Al-7Nb) in eco-friendly ADL slot shape machining was investigated using the response surface analysis method. As the design of the experiment, three levels of cutting speed, feed rate, and depth of cut were designed and the experiment was conducted using the central composite planning method. The regression expressions of cutting temperature and surface roughness were respectively obtained as quadratic functions to obtain the minimum value and optimal cutting conditions. The values from this formula and the experimental values were compared. As a result, this study makes and establishes the basis to prevent environmental pollution caused by the use of coolant and to replace it with ADL (Aerosol Dry Lubricant) machining that uses a very small amount of vegetable oil with high pressure.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.1
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• pp.126-133
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• 1993

Conventional cutting(CC) and Ultrasonic Vibration Cutting(UVC) of 20[KHz] are practised with standard lathe for fine ceramics(A1$_{2}$O$_{3}$. UVC is suggested to good cutting method for difficult-to-machine-materials and it is known to excellent cutting method to super precision cutting and elevation of productibility for general, nonferrous matals. In this research, main results to be obtained are as follows: 1. From the CC and UVC results by general lathe with sintering diamond tool, the surface roughness and roundness are improved in UVC. Also tool life is longer in UVC than CC. From the observation of machined surface, it is found that brittle fracutural material remove occured in fine ceramics cutting. 2. It is verified that the thrust force is the biggest in fine ceramics cutting, principal force is the next, and feed rate force the third and it is appear a little, on the other hand the principal force is the biggest in metal cutting, feed rate frece is the second, and thrust force is the next.

• Sim-seong Yeon-gu
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• v.25 no.1
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• pp.27-64
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• 2010

The main focus of this article investigates Jung's analytic implications of the Spiritual Exercises by St. Ignatius of Loyola. The Exercises is referred to not only as the tool for transformation that transformed Ignatius from a soldier of the world into a soldier of God and led him to a completely changed life but also as a tool which galvanizes self-realization, i.e., individuation process, in which a faithful experiences the presence of God in his life and is in search for himself in a new way. The interest in the Exercises regarded as a Western version of Yoga of the East which is a tool for transformation led Jung to give a series of 20 lectures on the Exercises in a seminar held in Zurich from 1939 to 1940. Curiosity about Jung's understanding on the Exercises provokes my desire to step into this research. The Exercises is a book for spiritual exercises that prepare and dispose one's soul to rid itself of all disordered attachments and to order one's life. The Exercises is made up of four Weeks. The First begins with 'Principle and Foundation' which illustrates what human beings are created for. It leads retreatants to rid themselves of disordered attachments and to have a new perspective on life by the consideration and contemplation of sins as the subversion of the Principle and Foundation. The Second is the period in which retreatants accept Christ as the Master of their lives through the meditation and contemplation of the life of Christ. In the Third, retreatants take part in the salvation history of Christ not only by actively participating in the Passion of Christ but also by incorporating the Passion into their lives. The Fourth aids retreatants to undergo their transformation and experience it deeply in order to participate in the new life of Christ who by His resurrection overcame death. In conclusion, Jung viewed the Exercises as a Western tool which plays the similar role of Yoga of the East which engenders inner transformation. The four-week-long retreat helps retreatants to meditate on God who unifies everything and is Himself/Herself the perfect union or the unity so that imperfect retreatants are given opportunities to undergo complete metamorphosis into the immortal, indivisible, and impeccable God. Jung understood that this metamorphosis leads human beings to the totality, that is, the genuine self as the image of God. The author interprets that it is the transformation that the Exercises tries to attain, which resonates with individuation, the key element of analytic psychology.

• Advances in aircraft and spacecraft science
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• v.4 no.1
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• pp.1-19
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• 2017

Fatigue life prediction of a multi-row countersunk riveted lap joint was performed numerically. The stress and strain conditions in a highly stressed substructure of the joint were analysed using a global/local finite element (FE) model coupling approach. After validation of the FE models using experimental strain measurements, the stress/strain condition in the local three-dimensional (3D) FE model was simulated under a fatigue loading condition. This local model involved multiple load cases with nonlinearity in material properties, geometric deformation, and contact boundary conditions. The resulting stresses and strains were used in the Smith-Watson-Topper (SWT) strain life equation to assess the fatigue "initiation life", defined as the life to a 0.5 mm deep crack. Effects of the rivet-hole clearance and rivet head deformation on the predicted fatigue life were identified, and good agreement in the fatigue life was obtained between the experimental and the numerical results. Further crack growth from a 0.5 mm crack to the first linkup of two adjacent cracks was evaluated using the NRC in-house tool, CanGROW. Good correlation in the fatigue life was also obtained between the experimental result and the crack growth analysis. The study shows that the selected methodology is promising for assessing the fatigue life for the lap joint, which is expected to improve research efficiency by reducing test quantity and cost.

• Research in Community and Public Health Nursing
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• v.14 no.4
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• pp.686-698
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• 2003

Purpose: This is a descriptive correlation study purposed to provide basic data for comprehensive nursing care by analyzing the relationship between the burden and the quality of life of family caregivers of cancer patients treated with chemotherapy. Methods: As for the subjects of this study, 66 family caregivers who take care of cancer patients hospitalized and treated with chemotherapy participated in the research. The tool of this study was a structured questionnaire including questions concerning burden(19 items) and the quality of life(33 items). Collected data were analyzed using SPSS PC+ program through descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and stepwise multiple linear regression. Results: 1) The mean score of burden was 2.6383. The mean score of quality of life was 3.3034. These score show that family caregivers perceive a moderate level of burden and the quality of life. 2) Family caregivers' burden was significantly related to symptoms in the cancer patient (r= 0.3501, P=0.0042) and family caregivers(r= 0.5340, P=0.0001). Family caregivers' quality of life was significantly related to symptoms in the cancer patient(r= -0.3528, P=0.0039) and family caregivers(r= -0.5472, P=0.0001). According to the result of examining' the relationship between burden and the quality of life, there was a statistically negative correlation(r= -0.6326, P=0.0001). 3) 'Family income after the onset of the patient' was the most important predictor of the burden of family caregivers($R^2$=0.158). 'Usual relationship with the patient' was the most important predictor of the quality of life of family caregivers($R^2$=0.138). Conclusions: The results presented above indicate that we must consider burden of family caregivers and symptoms experienced by them in order to improve the quality of life of family caregivers of cancer patients treated with chemotherapy.

• The Journal of Korean Society for Radiation Therapy
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• v.6 no.1
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• pp.154-170
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• 1994

The Purpose of this study was to determine the degree and contents composing the qualify of life and to analyze the relationships among the demographic characteristics, the degree of pain and the quality of life of the cancer patients experiencing a radiation therapy. The subjects for this study were 110 out-patients experiencing a radation therapy at C University Hospital in K-city, from April to October, 1992. The data were obtained using a convenience sampling technique. The tool of this study was the quality of life scale developed by Ro, You-Ja and the data were analyzed using a SAS program for percentages, mean & standard deviation. ANOVA and Scheffe test. The results were as follows : 1. the average total score of the quality of life of the subjects was 139.65(minimum score 121-maximum score 164), item mean score grange 1-5) was 2.97. For each factor in the quality of life scale, the mean scores (range 1-5) were 3.29 in emotional state, 3.14 in relationship with neighbors. 3.04 in physical state and function. 2.92 in self-esteem, 2.81 in economic life and 2.65 in relationship with family. 2. The incidence of physical symptoms was seen fatigue ($84.5\%$). anorexia ($65.5\%$) and weight loss ($47.3\%$) in order. The 50.9 percentage of the subjects complained of moderate or severe pain. 3. The results of the analysis of the relationships between the demographic variables and the quality of life were as follows : Gender (F=8.45, P=0.0044), age (F=6.29, P=0.0001). educational level (F=5.67, P=0.0046), marital status (F=6.82. P=0.0016), occupation (F=2.86, P=0.009), monthly income (F=6.90, P=0.0003), family living together (F=3.95, P=0.0494) and person paying a medical fee (F=5.14, P=0.0023). 4. The relationship between the degree of pain and the quality of life was significant difference (F=3.12, P=0.0482).