• The Transactions of the Korean Institute of Power Electronics
• /
• v.27 no.1
• /
• pp.80-83
• /
• 2022

This paper proposes an initial rotor polarity detection algorithm of a single-phase permanent magnet synchronous motor (SP-PMSM) related to stable open-loop starting for sensorless operation. Generally, the SP-PMSM needs an asymmetric air-gap structure to can avoid the initial starting failure at zero torque point. Therefore, the rotor polarity information can be obtained by using the DC offset current direction of a stator current through a high frequency voltage injection into an SP-PMSM with an asymmetric air gap. In this paper, the proposed rotor initial polarity detection algorithm is verified through several experimental results.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.7 no.1
• /
• pp.45-50
• /
• 2013

Recently, a method for detecting animal tinnitus objectively, gap prepulse inhibition of acoustic startling (GPIAS) were reported. However, the GPIAS method is difficult to be directly applied to human tinnitus research because measuring repeatedly startling responses evoked by more than 110 dB SPL acoustic stimuli for human is not easy. In this paper, the auditory late latency response (ALLR) measurement system which can measure conveniently evoked potentials involving the information about the brain cortical activity related with auditory psychologic phenomena such as a tinnitus has been implemented. By using the implemented system, 8 persons with normal hearing sense have been experimented to measure N1-P2 amplitudes of ALLRs evoked by gap prepulse based acoustic stimuli. Through the experimental results, the prepulse inhibitions of all the participants' N1-P2 responses have been observed and their characteristics were evaluated. And it is verified that our implemented system can be utilized as a device for researching and evaluating the objective tinnitus detection method in the future study.

• Proceedings of the Korea Society of Information Technology Applications Conference
• /
• 2006.06a
• /
• pp.414-435
• /
• 2006

• Journal of Food Hygiene and Safety
• /
• v.33 no.1
• /
• pp.12-22
• /
• 2018

The US government has enacted the Food Safety Modernization Act (FSMA) in 2011, which is being phased in and planned. The final Rules of Produce Safety focus on biological hazards related to agricultural production, harvesting, packaging and storage, which are being phased in since 2017 depending on farm scale. As a result of comparison with the Korean-GAP (Good Agricultural Practices) standards, it is difficult to compare the two standards to be compared with each other by 1:1. However, many of the Korean-GAP standards are similar to FSMA Produce Safety rules. However, the Korean-GAP standards can be judged differently according to the evaluator as a comprehensive standard, so the details of the standards need to be reinforced. In terms of the provisions, the Korean-GAP standards are the most appropriate for the safety of workers (FSMA Subpart D), followed by livestock and wild animals (FSMA Subpart I), buildings, equipment and tools (FSMA Subpart L) and harvesting activities (FSMA Sub-part K). However, there are some weaknesses in the field of agricultural water management (FSMA Subpart E) and farm manager's qualifications and training (FSMA Subpart C), and the response to the biological soil amendments of animal origin and human waste (FSMA Subpart F) is weak. The FSMA regulation is not a certification standard, but it is expected that the marbling effect, which is the standard laid down by the United States leading the world food safety standards, is expected to be considerable. Therefore, we hope that the review of the Korean-GAP standards will help improve the quality of agricultural products and expand our exports, since the standard for responding to microbiological safety emphasized in the FSMA regulations is the Korean-GAP standard.

• Journal of Korean Academy of Nursing Administration
• /
• v.3 no.1
• /
• pp.37-50
• /
• 1997

The purpose of this study was to identify the gap between need-level and demonstration-level in nursing managerial competencies. In addition, the study proposes solutions to narrow this gap. The results of this study are as follows : 1) The mean score for need-level of each item was 4.0, and for demonstration-level, 3.5. This indicates that military hospital head nurses demonstrate a higher level of managerial competencies than the moderate level on all items. But items which were related to resource/ cost/ information managament, staff development management and professionalism management got relatively low ratings in the need-level. 2) The mean score for need-level of each category was 4.14, and for demonstration-level, 3.53. Categories on the individual dimension got a higher rating than categories on the group or organization dimension in both need-level and demonstration level. 3) The gap between need-level and demonstration-level appeared in all items(p<.05) and categories(p<.001). Although the gap was relatively low, it indicates that it is essential to plan a developmemt program for all nursing management competencies for military hospital head nurses. 4) There were significant differences in the gap between need-level and demonstration-level according to specific characteristics of the subjects. The gap did not appear in many categories on the individual dimension where the number of nursing staff was more than 10, a major grade, ICU head nurse or for head nurses having a long career. 5) Need-level and demonstration-level showed a difference according to specific characteristics of the subjects, because need-level and demonstration-level were higher where the number of nursing staff was more than 10, a major grade, and for ICU or Medical ward head nurses. The categories which showed need-level difference and demonstration-level differences according to specific characteristics of the subjects existed almostly completely in the group and organization dimension. Gap-level differences according to the number of hospital bed existed in only two categories. 6) The general causes of the gap were indicated to be 'Knowledge/ skill/ experience deficit', 'Limitation of rules and systems/ Inappropriate organizational environment' for most items, categories, and dimensions. The results of this study indicate that extensive competency developing strategies must be developed, because a gap was found in all items and categories. Specially, there is a need to concentrate attention on competencies in the group and organizational dimension which had a wider gap level. And it is important to take an individual approach according to the cause for each gap. In order to produce effective competency developing strategies, top managers must have sinsights into the importance of nursing staff development and nursing officer's efforts to develop themselves must be achieved. Further multi-dimensional(education, personnel-policy, nursing/ organizational environment) solutions to the gap must be developed and utilized.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08b
• /
• pp.1519-1521
• /
• 2007

In this work, a coplanar-type plasma flat fluorescent lamp having cross type of electrode was fabricated by screen printing and sealing technique. Cross type of electrode with a dielectric layer were screen-printed on a rear glass plate, and then fired at $550^{\circ}C$. Phosphor was printed on and fired at $450^{\circ}C$. Finally, the lamp was sealed by frit glass at $450^{\circ}C$. The lamp of cross electrode type was studied depending on the electrode gap and the thickness of dielectric layer.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.743-746
• /
• 2006

We have demonstrated a transflective liquid crystal display (LCD) with a single cell gap in a patterned vertically aligned mode. In our configuration, the different electrode structure in a transmissive and a reflective part was suggested to compensate an optical path difference of each region. As the result, the similar electro-optic characteristic of each region was obtained which results in an enhanced performance of the device. Moreover, suggested technique can be highly effective to realize the practical transflective LCD due to the simple fabrication process.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.2D
• /
• pp.217-225
• /
• 2008

Bus stop is necessary to improve user-focused environment to offer convenient service because of the large number of passengers. This study is to analyze user's evaluation and establishment model of the service levels at bus stop using GAP analysis, IPA and Structural equation model and suggests improvement direction of bus stop. In the GAP analysis, on thirty-one service items of bus stop, the difference appeared highly from the items such as obstacle's facility and the information related to the using bus. In the current IPA service bus operation information, cadence facility and obstacle support facility need to be improved. And in service expectation bus operation information and th exchange facility, the obstacle support facility need to be improved continuously. The evaluation model of bus stop service due to a structure equation's was fitted well by structure equation. In overall satisfaction on bus stop, the waiting satisfaction is more affect the satisfaction of bus use facility. Satisfaction in bus use facility, the related information of bus operation, cadence facility, bus operation information and trans facility, obstacle support facility is more affect compare to other items. The lower overall satisfaction in bus stop is the higher the expectation of overall satisfaction is. Therefore, the information of bus operation and the support facility for the handicapped needs an active improvement plan than ever.

• Journal of the Korean Ceramic Society
• /
• v.48 no.2
• /
• pp.200-204
• /
• 2011

Increase of surface area and decrease of band gap in $TiO_2$ semiconductors are significant to improve the efficiency of water splitting by photoelectrolysis. In this study $TiO_2$ nanotube arrays with ~7 um length and ~100 nm diameter were fabricated by an anodizing technique of titanium foils using DMSO (dimethyl sulfoxide)-based electrolytes. Then to control the band gap of the $TiO_2$ arrays, they were annealed at $550^{\circ}C$ for up to 180 min in $NH_3$ gas ambient. The samples annealed in $NH_3$ gas for 30 min and 60 min showed superior photo-conversion efficiency for water splitting under white and visible light. A $TiO_2$ nanotube annealed in $NH_3$ gas ambient for a period longer than 120 min showed 1 order higher leakage current. It is believed that the decrease of band gap and increase of conductivity in $TiO_2$ nanotube arrays due to $NH_3$ gas treatments result in the superior water-splitting performance.

• Proceedings of the KIEE Conference
• /
• 2004.11a
• /
• pp.46-48
• /
• 2004

A micro-scale discharge device has been fabricated using MEMS technology and failure mechanisms during DC discharge are investigated for the microstructure. The failure of sustaining the plasma is mainly caused by either open or short of the micro-electrodes, both resulting from the sputtered metal atoms during the DC discharge. The glow discharge lifetime of the microstructures is found to depend on bias circuit scheme as well as the electrode structure. Based on the understanding of the failure mechanism, a novel microstructure is suggested to improve discharge lifetime and the longer lifetime is experimentally demonstrated. In addition to the failure mechanism, an electric breakdown between two electrodes with microns gap are studied using micromachined metal structures. The electrode gap is able to be accurately controlled by thickness of a sacrificial layer and the electric breakdown was measured while varying the gap from $2{\mu}m$ to $20{\mu}m$. The electric breakdown behavior was found to highly depend on the electrode material, which was not considered in Paschen's law.