• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.56-64
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• 2004

In this research, design results of computer hardware which control solid motor movable nozzle thrust vector control(TVC) actuator for Korea Space Launch Vehicle I(KSLV-I) are described. TVC computer hardware is the equipment which has jobs for receiving control commands from Navigation Guidance Unit(NGU) and then actuating TVC actuator. Also, it has ability to communicate with other on board or ground equipments. Computer hardware has a digital signal processor as the main processor which is capable of high speed calculating ability of control algorithm, so it can have more stability, reliability and flexibility than the previous analog controller of KSR-III. Target board was designed for on board program development and then first prototype hardware was developed. Top level system design criteria, hardware configurations and ground support equipment of TVC computer system are described.

• Tribology and Lubricants
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• v.21 no.2
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• pp.71-76
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• 2005

This paper compares of mechanical tensile properties of 6 kinds of copper foil. The beam lead made with copper foil. Different from other package type such as plastic package, Chip Size Package has a reliability problem in beam lead rather than solder joint in board level. A new tensile loading system was developed using voice-coil actuator. The new tensile loading system has a load cell with maximum capacity of 20 N and a non-contact position measuring system based on the principle of capacitance micrometry with 0.1nm resolution for displacement measurement. Strain was calculated from the measured displacement using FE analysis. The comparison of mechanical properties helps designer of package to choose copper for ensuring reliability of beam lead in early stage of semiconductor development.

• The Korean Journal of Food And Nutrition
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• v.22 no.1
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• pp.57-62
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• 2009

The current exploratory study attempted to investigate the levels of expected and perceived service quality of in-flight meals. A questionnaire was developed following extensive literature review and in-depth interviews. The survey was conducted on board a flight by international passengers and also by passengers in the trans lounge waiting for connecting flights between October 21, 2005 through October 30, 2005. Out of the 450 questionnaires administered, a total of 319 completed questionnaires were returned, yielding a response rate of 89.6%. The 20 items representing the service quality factor of in-flight meals were analyzed, resulting in four distinct dimensions-food quality, employee service, cleanliness and reliability. In all dimensions, customer expectation was higher than the perceived level of service and the service quality of Korean based airlines was higher than that compared to foreign based airlines. There were differences in the perceived service quality of in-flight meals according to the demographics of the respondents. The results of this study can be beneficial from a theoretical and practical point of view by providing empirical data that measures the service quality of in-flight meals.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.1
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• pp.177-185
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• 2019

Service quality is still a new concept to those who works in shipping lines services since it has not been identified as a mandatory factor to increase competitiveness. Most carriers are currently offering services at the same level of price, transit time, equipment, etc. Thus offering a high quality service is the best way for a carrier to differentiate itself from its competitors in the market. The research aims to conduct an assessment on service quality at Wan Hai Lines (WHL) outbound services based on the SERVQUAL model, form of dimension-by-dimension analysis. This study was based on a survey of 135 people. The outcome is the service quality of WHL outbound services can be identified by three dimension(s): Empathy and Responsiveness, Assurance, and Reliability. It would help management to have an overall picture about the current service quality, and to find solutions to improve service quality following the recommendations. WHL managers need to recognize that "Reliability" has the strongest influence on customers' expectations, then come "Empathy and Responsiveness" and "Assurance". Therefore, board of managers should spend time looking carefully at each of the three dimensions, especially for the biggest gap between perceptions and expectations of three dimensions as well. Then the recommendations were raised.

• International Journal of Automotive Technology
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• v.3 no.1
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• pp.33-40
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• 2002

Increasingly stringent emission regulations of EU and CARB (California Air resource Board) require mandatory OBD (On Board Diagnostics) far the catalytic converters of a vehicle. It demands that MIL(Malfunction Indication Light) should be tuned on to inform the driver of catalytic converter failures. Currently dual oxygen sensor method Is widely used for the converter OBD. However, since it works only alter converter light-off, it has a serious limitation when applied to TLEV or more stringent emission regulations where more than 85% of total emission is coming out before converter light-off. In addition, a recent development in catalyst material. coating technology and additive catalysts leads to a much improved OSC (Oxygen Storage Capacity) after converter light-off, current methods are very difficult to determine levels of converter aging. Therefore, it is desired to develop an OSC detecting method before converter light-off to diagnose converter failures with higher reliability. In this study, OSCs of converters are measured by an absolute measuring method and a dynamic measuring method, and some of fundamental ideas are suggested about converter OBD before converter light-off. The converters are aged with two different aging methods; those are a furnace aging and an engine bench aging: to represent aging conditions in actual field applications. Dual oxygen sensor method at the lower temperature than light-off is also studied at a model gas bench with the converters. It is fecund that there is a certain point in temperature lower than light-off where difference due to aging level becomes maximum, thus a proper dynamic method to effectively monitor catalytic converters could be implemented fur the range lower than light-off temperatures. With this result, the aging level of converters is examined at an engine bench.

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.269-272
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• 2004

Printed circuit boards (PCB) replaced conventional wiring in most electronic equipment I, reducing the size and weight of electronic equipment while improving reliability, uniformity, precision and performance. PCB is used in all kinds of electronic products because they can be mass-produced with very high circuit density and also enable easier trouble-shooting. This paper presents the analyses of the patent information of Build-up PCB which is seen as the most promising solution, as its substrate supports multi-level packaging, thinner board profiles and smaller pitches.

• Archives of Plastic Surgery
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• v.32 no.6
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• pp.675-682
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• 2005

This is the evaluation report of clinical competence of undergraduate medical students in Plastic Surgery field using OSCE(Objective Structured Clinical Examination) executed in three years. OSCE comprises of assessment of subject, choice of clinical stations sampling, identification of components of clinical competence to be evaluated, the level of performance required, development of specification table, editing of OSCE presentation page and assessment of practicability and results exploitation. About fifty students were examined annually. Seven station stimuli with simulated patient participation were carried out. The mean OSCE score was $82.3{\pm}6.19$. The reliability of the total station was 0.72. The examination shows a positive response to the OSCE. Our experience shows OSCE's feasibility for Plastic Surgery during the initial course of education. Referring to our experiences, the Korean Society of Plastic and Reconstructive Surgeons (KPRS) applied the OSCE test for Korean Plastic Surgery Board Certification

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1168-1170
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• 1993

EHV underground transmission cable characterized by low loss and bulk capacity should have high reliability to be protected fully from external damages, not to speak of its quality. In 345kV underground transmission lines of our country, the usage of frie protection trough is standardized. Fire protection trough consists of combination of trough body, spacer, shutting board, fastener, and etc. and it is required to have a high level of fire-retardant characteristics and mechanical strength. Since 1992, we, GoldStar Cable, with collaboration of Lucky, have participated in the development of fire protect ion trough and completed the type test of manufacturing site and will be supposed to go into mass product within 1993.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.53-58
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• 2003

The Wafer Level Packaging is one of the most important technologies in the semiconductor industry today. Its primary advantages are its small form factor and low cost potential for manufacturing including test procedure. The CASIO's WLP samples, application example and the structure are shown in Fig.1, 2&3. There are dielectric layer , under bump metal, re-distribution layer, copper post , encapsulation material and terminal solder .The key technologies are 'Electroplating thick copper process' and 'Unique wafer encapsulation process'. These are very effective in getting electrical and mechanical advantages of package. (Fig. 4). CASIO and CMK are developing a new System Packaging technology called the Embedded Wafer Level Package (EWLP) together. The active components (semiconductor chip) in the WLP structure are embedded into the Printed Wiring Board during their manufacturing process. This new technical approach has many advantages that can respond to requirements for future mobile products. The unique feature of this EWLP technology is that it doesn't contain any solder interconnection inside. In addition to improved electrical performance, EWLP can enable the improvement of module reliability. (Fig.5) The CASIO's WLP Technology will become the effective solution of 'KGD problem in System Packaging'. (Fig. 6) The EWLP sample shown in Fig.7 including three chips in the WLP form has almost same structure wi_th SoC's. Also, this module technology are suitable for RF and Analog system applications. (Fig. 8)

• Journal of Welding and Joining
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• v.24 no.6
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• pp.21-27
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• 2006

This study was focused on the evaluation of the thermo-mechanical board-level reliability of Pb-bearing and Pb-free surface mount assemblies. The composition of Pb-bearing solder was a typical Sn-37Pb and that of Pb-free solder used in this study was a representative Sn-3.0Ag-0.5Cu in mass %. Thermal shock test was chosen for the reliability evaluation of the solder joints. Typical $Cu_6Sn_5$ intermetallic compound (IMC) layer was formed between both solders and Cu lead frame at the as-reflowed state, while a layer of $Cu_3Sn$ was additionally formed between the $Cu_6Sn_5$ and Cu lead frame during the thermal shock testing. Thickness of the IMC layers increased with increasing thermal shock cycles, and this is very similar result with that of isothermal aging study of solder joints. Shear test of the multi layer ceramic capacitor(MLCC) joints was also performed to investigate the degradation of mechanical bonding strength of solder joints during the thermal shock testing. Failure mode of the joints after shear testing revealed that the degradation was mainly due to the excessive growth of the IMC layers during the thermal shock testing.