• Journal of the Korean Society for Heat Treatment
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• v.7 no.4
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• pp.244-252
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• 1994

The morphological changes of primary solid particles as a fuction of process time on Al-Si alloys during semi-solid state processing with a shear rate of 200s were studied. In hypereutectic Al-15.5wt%Si alloy, it was observed that primary Si crystals are fragmented in the early stage of stirring and morphologies of primary Si crystals change from faceted to spherical during isothermal shearing for 60 minutes. In quaternary Al-12.5wt%Si-2.9wt%Cu-0.7wt%Mg alloy system, it was observed both primary silicon and ${\alpha}$-alumunum particles. Microstructural evolution of primary Si crystals was similar to that of the hypereutectic Al-Si alloy but equiaxed ${\alpha}$-Al dendrites are broken into nearly spherical at the early stage of shearing and later stage of the isothermal shearing ${\alpha}$- Al particles are slightly coarsoned by Ostwald ripening. Mechanical properties of Al-Si-Cu-Mg alloy were compared to those from other processes (squeeze casting and gravity casting). After T6 heat treatment, comparable values of hardness were obtained while slightly lower compressive strength values were observed in rheocast alloy. The elongation, on the other hand, exhibited significant increasement of 15% over gravity cast alloy.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.678-686
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• 2009

The purpose of this study was to investigate changes in the cooking process of red beans used to prepare Bab (cooked rice) in cooking books published from late 19th century to the present. There are 3 different types of Bab that use red beans; Jungdeungbab, Patbab and Patsura, and cooking process vary between different cooking books. For making Jungdeungbab, one method is to cook the red beans in the water first, and then only the water, after draining the cooked red beans, is used to cook rice. The other method is to smash the cooked red beans and collect the water that passes through the smashed red beans to cook the rice. For Patbab, 2 cooking methods were found. One is to cook the whole red beans first and then to add them to the rice for cooking. Another method is to break the red beans into two pieces and mix them with rice and cook them together. Patsura is the red bean used to prepare the Bab offered to Kings during the Chosun dynasty(1392~1910). The cooking process of Patsura is similar to both Jundeungbab and Patbab. In Ijogungjeongyoritonggo(1957), the cooking method of Patsura is similar to that of Patbab; breaking red beans into two pieces and then mixing them with rice and cooking them together. Another method, which is similar to Jungdeungbab, is found in Ijogungjeongyoritonggo(1957) and Hangukyoribaekguasajeon(1976). In Ijogungjeongyoritonggo(1957), the cooking method is to cook the red beans first and then squeeze them after putting them into a sack and then using the extract to cook rice. In Hangukyoribaekguasajeon(1976), the red bean is prepared by first cooking red beans in water, and then only the water, after draining the cooked red bean, is used to cook rice. In further studies, the cooking procedures used in the previous period of the late 19th century should be examined.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.2
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• pp.114-125
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• 2002

As semi-solid forging (SSF) is compared with conventional easting such as gravity die-easting and squeeze casting, the product without inner defects can be obtained from semi-solid forming and globular microstructure as well. Generally speaking. SSF consists of reheating, forging, ejecting precesses. In the reheating process, the materials are heated up to the temperature between the solidus and liquidus line at which the materials exists in the form of liquid-solid mixture. The process variables such as reheating time, reheating temperature, reheating holding time, and induction heating power have much effect on the quality of the reheated billets. It is difficult to consider all the variables at the same time when predicting the quality. In this paper, Taguchi method, regression analysis and neural network were applied to analyze the relationship between processing conditions and solid fraction. A356 alloy was used for the present study, and the learning data were extracted by the reheating experiments. Results by neural network were on good agreement with those by experiment. Polynominal regression analysis was formulated by using the test data from neural network. Optimum processing condition was calculated to minimize the grain size, solid fraction standard deviation, otherwise, to maximize the specimen temperature average. In this time, discussion is liven about reheating process of row material and results are presented with regard to accurate process variables for proper solid fraction, specimen temperature and grain size.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.6 s.183
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• pp.166-173
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• 2006

In this study, a probe array has been developed for use in a data storage device that is based on scanning probe microscope (SPM) and MEMS technology. When recording data bits by poling the PZT thin layer and reading them by sensing its piezoresponse, commercial probes of which the tip heights are typically shorter than $3{\mu}m$ raise a problem due to the electrostatic forces occurring between the probe body and the bottom electrode of a medium. In order to reduce this undesirable effect, a poly-silicon probe with a high aspect-ratio tip was fabricated using a molding technique. Poly-silicon probes fabricated by the molding technique have several features. The tip can be protected during the subsequent fabrication processes and have a high aspect ratio. The tip radius can be as small as 15 nm because sharpening oxidation process is allowed. To drive the probe, electrostatic actuation mechanism was employed since the fabrication process and driving/sensing circuit is very simple. The natural frequency and DC sensitivity of a fabricated probe were measured to be 18.75 kHz and 16.7 nm/V, respectively. The step response characteristic was investigated as well. Overshoot behavior in the probe movement was hardly observed because of large squeeze film air damping forces. Therefore, the probe fabricated in this study is considered to be very useful in probe-based data storages since it can stably approach toward the medium and be more robust against external shock.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.9
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• pp.131-161
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• 1998

None of us need to be reminded that these are exceedingly times. The evidence in all about us. Between rising costs and lowering prices, many businesses find profits being depressed almost to the vanishing point. The eating out food business is in just such a profit squeeze. Our ability to compete depends not only on our ability to control the price-cost picture, but to improve its kitchen product system. A kitchen product system is incomplete without a series of built-in improvement procedures. They must be a key part of the system. "improvement" means the continual betterment of all aspects of the operation-its personnel, products, sales, and its costs. These improvements create profits. This study is devoted to a discussion of the application of research methods and techniques to develop of modern kitchen system through the job standardization. Their use in executing other responsibilities related to the process of kitchen system improvement will also be seen. The steps of setting objectives, gathering data, analyzing and interpreting data, and arriving at solutions, conclusions, and/or recommendations are briefly out lined. The material presented emphasizes the need for an improved and systematic approach to the study of problems. It is also implied, of not stated, that the process should not become so mechanical that the principles of creativity are violated. The foregoing steps suggest a systematic approach to kitchen system improvement, finding solutions to problems, improving work methods, instituting changes, followting up on work related to the change. This study has been limited to the truly important points related to each step in the process, it will undoubtedly call to mind other factors for consideration, however, believe that the principles and approach suggested in this study will bring about better methods and improve kitchen operating results.g results.

• Journal of Communications and Networks
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• v.18 no.5
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• pp.744-761
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• 2016

For about the past decade and a half research efforts into cognitive radio networks (CRNs) have increased dramatically. This is because CRN is recognized as a technology that has the potential to squeeze the most out of the existing spectrum and hence virtually increase the effective capacity of a wireless communication system. The resulting increased capacity is still a limited resource and its optimal allocation is a critical requirement in order to realize its full benefits. Allocating these additional resources to the secondary users (SUs) in a CRN is an extremely challenging task and integer programming based optimization tools have to be employed to achieve the goals which include, among several aspects, increasing SUs throughput without interfering with the activities of primary users. The theory of the optimization tools that can be used for resource allocations (RA) in CRN have been well established in the literature; convex programming is one of them, in fact the major one. However when it comes to application and implementation, it is noticed that the practical problems do not fit exactly into the format of well established tools and researchers have to apply approximations of different forms to assist in the process. In this survey paper, the optimization tools that have been applied to RA in CRNs are reviewed. In some instances the limitations of techniques used are pointed out and creative tools developed by researchers to solve the problems are identified. Some ideas of tools to be considered by researchers are suggested, and direction for future research in this area in order to improve on the existing tools are presented.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.365-373
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• 1999

Somatostatin (SOM) is one of the major neuropeptides in dorsal root ganglion cells, but its role in spinal nociceptive process has not been well known. In present study we aimed to investigate the effect of SOM on the response of dorsal horn neurons to the various types of peripheral nociceptive stimuli in anesthetized cats. Using carbon-filament microelectrode, the single cell activities of wide dynamic range neurons were recorded from the lumbosacral enlargement after noxious mechanical (squeeze), thermal (radiant heat lamp) and cold (dry ice) stimulation to the receptive field. Sciatic nerve was stimulated electrically to evoke $A\;{\delta}-$ and C-nociceptive responses. SOM analogue, octreotide $(10\;{\mu}g/kg),$ was applied intravenously and the results were compared with those of morphine (2 mg/kg, MOR). Systemic SOM decreased the cellular responses to the noxious heat and the mechanical stimulation, but increased those to the cold stimulation. In the responses to the electric stimuli of sciatic nerve, $A\;{\delta}-nociceptive$ response was increased by SOM, while C-nociceptive response was decreased. On the other hand, MOR inhibited the dorsal horn cell responses to all the noxious stimuli. From the above results, it is concluded that SOM suppresses the transmission of nociceptive heat and mechanical stimuli, especially via C-fiber, while it facilitates those of nociceptive cold stimuli via $A\;{\delta}-fiber$.

• Journal of Korean Physical Therapy Science
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• v.22 no.1
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• pp.29-36
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• 2015

Purpose : The purpose of present study was to improve communication of pain expressing terms and pain intensity between patient and physical therapist, and initiated to objectify a measurement of subjective pain. Methods : Data were delivered to 249 people by a self-completion questionnaire, and analyzed 160 copies except for 87 mark error of the collected 247 questionnaires. The questionnaire included a question on 55 terms used to describe pain, the type of the pain, and pain intensity using VAS (visual analogue scale). Results : The results were as follows; 'Tight' was the most frequently being expressed term of muscular pain, subsequently to 'knot' and 'dull'. 'Tear' was the term representing the most strong pain of muscular pain, subsequently to 'rupture' and 'squeeze'. 'Stinging' was the most frequently being expressed term of neurologic pain, subsequently to 'get shocked' and 'wriggle'. 'Burn' was the term representing the most strong pain of neurologic pain, subsequently to 'sear' and 'get shocked'. 'Creak' was the most frequently being expressed term of joint pain, subsequently to 'peel' and 'out of joint'. 'Break' was the term representing the most strong pain of joint pain, subsequently to 'peel' and 'crack'. Conclusion : The objectification of pain terms will be used to help physical therapist to check the patient's pain.

• Nutrition Research and Practice
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• v.6 no.1
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• pp.9-15
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• 2012

This study was performed to examine the feeding effects of $Angelica$ $keiskei$ $Koidz$ (AK) and its processed products on serum, liver, and body fat content and the expression of antioxidant genes in rats fed a high fat diet. AK and its processed products were added at 3-5% to a high fat diet and fed to adult rats for 6 weeks. In experiment 1 (EXP 1), the rats were fed with one of six diets including a control diet (normal fat), high fat diet (HF), and HF + AK additives groups (four groups). In experiment 2 (EXP 2), the rats were separated into three groups of HF, HF + AK whole leaves, and HF + fermented juice (FS) + squeeze (SA). Body weight was not different among the groups in either experiment. The liver weight was lower in the FS and SA groups compared to that in the other groups (P<0.05). Serum luteolin was higher in the AK and processed products groups compared to that in the HF group (P<0.05). Gene expression of the antioxidative enzymes catalase and glutathione-s-reductase in the liver was higher in the AK processed products group than that in the other groups (P<0.05). The results suggest that the intake of AK and its processed products increased the expression of antioxidant enzymes in animals fed a high fat diet, reduced hepatic cholesterol content, and increased the effective absorption of luteolin.

• Korean Journal of Materials Research
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• v.2 no.6
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• pp.461-467
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• 1992

A fabrication process for SiC whisker preform reinforced AC4A Al composites is being developed. The Al alloy used as the matrix in this study is AC4A. SiC whisker preform made by Tokai Carbon Co. Ltd. Shizuoka, Japan were used. These consisted of $\beta$-type single crystals 0.1 ~ 10${\mu}$m in diameter and 20~10${\mu}$m in length. The most adequate fabrication condition was that whisker preform was preheated up to 750~80$0^{\circ}C$, set into a mould preheated to ~40$0^{\circ}C$, molten Al alloy heated to ~80$0^{\circ}C$ and applied pressure 75MPa. And Si$C_w$reinforced AC4A composite was advanced above twice than AC4AI/M. Also it was not large effect by pressure at Si$C_w$ 20v/o.