• Journal of the Korean Society for Precision Engineering
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• v.7 no.3
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• pp.26-36
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• 1990

This paper describes the Computer Aided Design (CAD) of dies for direct hot extrusion of structural shapes such as Z's and U's from aluminum alloys. A simple analysis of the direct extrusion process is developed and used to formulate a disign procedure for determining the optimal shape of the extrusion dies. A computer software system has been developed to design flat-faced dies for non-lubricated hot extrusion process. This software is a system of computer programs which are written to logical design procedure. Computer programs are based on empirical and analytical relationships, as well as on established knowledge based system. In the interactive mode of operation, the reaults at various tages of the design process are plotted on a screen. At any stage, the designer can interact with the computer to change or modify the design, based on his experience. The output from the program is (a) the design of the flat-faced die, (b) information on extrusion load, reduction ratio, and other process variables, etc. The implementation of this CAD system is expected to (a) provide scientific basis and rationalize the die design procedure, (b) optimize extrusion variables to maximize yield and production rate, (c) improve utilization of existing press capacity, etc.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.1
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• pp.96-111
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• 1996

The failure of water pipelines is progressed by several compound factors and the collection and analysis of data about pipeline failure are inevitable for effective pipeline rehabilitation. Data analysis of pipeline failure was already performed in USA and Europe. Based on such phenomena, failure characteristics about metropolitan pipelines in Korea were analyzed: The conclusions of this study are as followings. 1. The failure cause of pipelines can be classified into natural cause and artificial cause. Artificial cause is 32% of total causes, so artificial failure as several constructions happens frequently in Korea. Although the failure by old pipe is greatest of any other causes m classtfied cause, failure cause is not classified in detail now. 2. The damaged part of pipelines is affected by cities, distribution system inventory, bedding conditions, and so on. In this study, the failure of pipeline body(67%) is greater than the failure of pipeline joint(33%) in natural failure. 3. In regard to pipe materials, failure rate of DCIP(0.8456), PEP(0.7288), and GSP(0.6643) is greater than that of CIP(0.3985) and CWSP(0.2348). 4. Usually, faIlure rate is increased in proportion to diameter of pipeline. In this study, CIP, DCIP, and CWSP have clear trends. But the trends of PEP is reverse, the case of GSP, HP is obscure due to data shortage. 5. There are no direct relationships between burial age and failure rate of pipelines. 6. Annual breaks and winter(Nov.~Feb.) breaks of pipelines are investigated. As a result, WInter breaks to annual breaks of CIP is 51.3%(Seoul), 51.1%(Taegu),38.7%(Pusan). This phenomena have direct correlation with average winter temp. of cities.

• Biomolecules & Therapeutics
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• v.2 no.3
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• pp.286-291
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• 1994

The mutagenicity of DA-3030(rhG-CSF)was studied by reverse mutation test, chromosome aberration test and micronucleus test. The reverse mutatuon test in bacteria was performed using salmonella typhimurium strain TA100, TA98, TA1535 and TA1537 with rhG-CSF in any of the concentrations(150, 75, 37.5, 18.75, 9.375 and 4,6875 $\mu\textrm{g}$/plate), no increase in the number of revertant colonies in each strain was observed, irrespective of treatment with the metabolic activation system(S-9 mix) The chromosome aberration test was carried out using CHL cells, cell line from chinese hamster lung. With 4 doses(75, 37.5, 18.75 and 9.375 $\mu\textrm{g}$/ml) of rhG-/CSF the cells were treated for 24 or 48 hours in the direct method or for 6 hours followed by 18 hour-expression time in the metabolic activation method. Results of the study showed, by the direct method or metabolic activation method, no trend toward increase in the number of aberrant metaphase. The micronucleus test was carried out using ICR mice at the age of 8 weeks. Three doses(862.5, 1725 and 3450 $\mu\textrm{g}$/kg) of DA-3030 were admintstered intraperitoneally with single shot and bone marrow cells were sampled at 24 hours after administration. Neither the number of polychromatic erythrocytes with micronuclei nor the ratio of normochromatic erythrocytes to polychromatic erythrocytes increased singinficantly in each dose, compared with a vehicle control. These results indicate that rhG-CSF has not mutagenic potential under the condiions.

• Journal of Communications and Networks
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• v.12 no.5
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• pp.433-441
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• 2010

Multihop transmission is a promising technique that helps in achieving broader coverage (excellent network connectivity) and preventing the impairment of wireless channels. This paper proposes a cluster-based multihop wireless network that makes use of the advantages of multihop relaying, i.e., path loss gain, and partial relay selection in each hop, i.e., spatial diversity. In this partial relay selection, the node with the maximum instantaneous channel gain will serve as the sender for the next hop. With the proposed protocol, the transmit power and spectral efficiency can be improved over those in the case of direct transmission and conventional multihop transmission. Moreover, at a high signal-to-noise ratio (SNR), the performance of the system with at least two nodes in each cluster is dependent only on the last hop and not on any of the intermediate hops. For a practically feasible decode-and-forward relay strategy, a compact expression for the probability density function of the end-to-end SNR at the destination is derived. This expression is then used to derive closed-form expressions for the outage probability, average symbol error rate, and average bit error rate for M-ary square quadrature amplitude modulation as well as to determine the spectral efficiency of the system. In addition, the probability of SNR gain over direct transmission is investigated for different environments. The mathematical analysis is verified by various simulation results for demonstrating the accuracy of the theoretical approach.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1282-1285
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• 2004

The high voltage driving system with multi-phase shifter including piezoelectric actuators comprised a driving power unit for outputting the driving power by converting input alternate current into direct current, a frequency shifting unit for supplying the direct current power and shifting or generating a frequency, a high-voltage amplification unit for amplifying the input signal outputted from the driving power unit and the frequency shifting unit into a high-voltage signal, and a phase shifting unit for shifting the phase difference of the amplified signal applied to the high-voltage amplification unit and driving plural piezoelectric actuators sequentially. The results that the operating voltage was stable, the voltage loss ratio was low and the response velocity was fast could be obtained. An experiment on performance of the high voltage driving system with multi-phase shifter designed and manufactured as above described was conducted by using a piezoelectric pump having 3 sheets of round unimorph piezoelectric actuators laminated respectively in a rectangular case. It sucks any fluid by causing the first piezoelectric actuator to shift from the inlet porter side, the phase delay of 60$^{\circ}$ causes the second piezoelectric actuator to begin to shift, and the phase delay of 120$^{\circ}$ causes the third piezoelectric actuator to begin to shift. As a result of measuring each change in the outlet flow rate of the piezoelectric pump, it was shown that the frequency-flow rate characteristic, the voltage-flow characteristic, and the load pressure-flow rate characteristic were improved.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.7
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• pp.61-85
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• 1997

1. Background of the Study Old Testament time made some food and Sauces. Cosher food is God's Covernant. Ancient Greek cooking and Roman cooking had been Sauces. Much of what we know of Greek gastronomy is found in the writting of Archestrate, cooking is sigle and direct, Sauces are Cumin, Vinegar, Roman culinary comes from mareus, first century A.D. many of the ingredients used in apicius's recipes are seen againg in midival Eurpean cooking. ① Cumin Sauce for Oyster ② Sauce for grounds, puree, and cardoons. 2. Culinary in the Middle ages Liaquid Flavorings their Sauces tested Verjuice and Vinegar are most often called for when a Liquid is needed, Spices and Liaisons. 3. Cookery the eighteenth century The eighteen the century brought about greated Systemization of basics, coulis, Jus, and bouillons. 4. The twentieth century culinary Careme were Systematized and recorded by Auguste Escoffier in his Guide Culinare Standardized. 5. Grand Sauces are Considered one of the greatest test of a Chef's Skill, Whether they are classics, Such as Sauce, Supreme, demand the highest technical expertise. The Successful paring of Sauce with a good demonstrates an understanding of the food and an ability to judge. Sauce making allows the cook more freedom to work flavors, textures, Aromatics, Tasty, and color than any other area of cooking. A Sauce is never eaten alone, function, balance, the direct flavor, Sauces presents the basic Sauce-making techniques that have been used in the past and that are popular today, Sauces are organized around the primeifhes of classic world cooking 6. Grand Sauces are 1) Brown Sauces are 1) Brown Sauce ① Demiglace ②Espagnole ③ Fond de veau 2) Bechamel Sauce 3) Velote Sauce 4) Tomato Sauce and 5) Hollandaise Sauce ① Brown Sauce made with Stock, Roux, Tomato Paste and Mirepoix. ② Bechamel Sauce made with Roux and Milk. ③ Veloute Sauce made with Roux and White Stock. ④ Tomato Sauce made with Tomto, Vegetable and Stock. ⑤ Hollandaise Sauce made with Egg and Butter.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.5
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• pp.1096-1101
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• 2004

The 3-D shape use to effect of movie, animation, industrial design, medical treatment service, education, engineering etc.... But it's not easy to make 3-D shape from the information of 2-D image. There are two methods in restoring 3-D video image through 2-D image; First the method of using a laser; Secondly the method of acquiring 3-D image through stereo vision. Instead of doing two methods with many difficulties, I figure out the method of simple 3-D image in this research paper. We present here a simple and efficient method, called direct calibration, which doesn't require any equations at all. The direct calibration procedure builds a lookup table(LUT) linking image and 3-D coordinates by a real 3-D triangulation system. The LUT is built by measuring the image coordinates of a grid of known 3-D points, and recording both image and world coordinates for each point; the depth values of all other visible points are obtained by interpolation.

• Journal of the Korea Society of Computer and Information
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• v.7 no.4
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• pp.8-15
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• 2002

This Paper proposes designing and implementing the database system storing the medical images. This system collects the medical image when doctors operate and diagnose the patients using the endoscope in the orthopedics, then stores the medical image data to database. Therefore. system avoids duplicated medical data, retrieves and updates the medical data effectively. The medical image data can be shared to the multiple users and application programs. This system consists of the five components. that is, the input module acquiring the medical image from the endoscope. the modulo storing the medical image. the database design and implementation storms the patient's disease history and the medical image data, user friendly interface design and implementation, and the simple data retrieval engine. The features of the system are followed. The image catcher program using DirectShow is portable any image catcher board And because the image catcher algorithm is implemented as a public module, The throughput can be increased during the development of video and audio contents on internet.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.2
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• pp.103-109
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• 2017

Metal 3D printing, which is an additive metal manufacturing (AMM) process, enables the development of full-density metallic tools and parts using metal powders that are precisely delivered and controlled for deposition with no powder bed. However, some unknown geometric defects and irregular geometric features on an STL model can possibly result in incorrect metal part fabrication after the build. This study first proposes a methodical approach for verifying the build part, including the missing facet problems in an STL model, by defining some irregular features that possibly exist on the part. Second, 2D tool paths on each build layer were investigated for detecting any singular region inside the layer. The method was implemented for building two sample STL models using a direct energy deposition process, and finally, it was visually simulated for diagnosis.

• The Journal of Korean Association of Computer Education
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• v.14 no.1
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• pp.23-33
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• 2011

The purpose of the study is to investigate the structural relations between variables which give influences on cyber-violence. On the basis of literal materials, those variables as self-control ability, social identity, and norm consciousness are selected as the variables of having influences on cyber-violence, and the analysis is focused on the influence that anonymity, the representative characteristic of Internet, gives them. The validation of the Model is to be done through AMOS 6.0, and the degree of Model validity is to be estimated through the values of ${\chi}^2$, RMSEA, CFI, NNFI. As the result of the analysis, it is found that social identity and norm consciousness are direct causes of cyber-violence. Anonymity does not have any direct relations with it, but it indirectly gives influences on cyber-violence, for it gives some influences on social identity and norm consciousness. That is, anonymity is a cause of weakening social identity and degrading norm consciousness, by which, it is assumed, cyber-violence is triggered.