• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.210-213
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• 2002

This paper addresses the design and implementation of compensation of rain attenuation for Ka-band satellite communication system complied with DVB-RCS[2]. A structure of rain fade compensation scheme in the Ka-band satellite communication system is presented. Rain fade compensation scheme in this paper is mainly applied into return-link, which is the path through which user terminal transmit the data tn hub system providing a service. Symbol rate and code rate of channel code are used as variable transmission parameter for rain fade compensation. For estimation of channel environment, SNR of the user terminal which is measured by demodulator of hub system is used. Rain fade compensation scheme in the paper changes the symbol rate and/or code rate according to the measured SNR so that it can compensate the attenuation of the signal.

• 대한임베디드공학회논문지
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• 제18권5호
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• pp.209-215
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• 2023

This study proposes an AC servo motor control program structure and its implementation method to efficiently integrate 13 types of additional compensation algorithms into the basic FOC (field-oriented control) algorithm program. Various compensation algorithms are necessary to enhance the stability and performance of machine tools by compensating for interference from disturbances and vibrations. Each compensation algorithm is implemented as a separate, independent function and called from a switch-case statement in the ISR (interrupt service routine) of the PWM (pulse-width modulation) device. The advantages of this approach include facilitating not only debugging and testing but also reducing the possibility of errors during the program development phase. Thus, it is easy to add and activate each specific compensation algorithm for the program update during the program operation phase. The implemented motor control program was experimented with a single-axis feed shaft testbed driven by a commercial AC servo motor control drive board and a 750 Watts SPMSM (surface-mounted permanent magnet synchronous motor), and the results verified its normal operation and performance improvement.

• 품질경영학회지
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• 제35권4호
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• pp.111-122
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• 2007

The purpose of the study is to find out the influences of various efforts on service recovery after the failure of the service for the customer satisfaction and a loyalty. The present study finds out the factors directly affecting service recovery and demonstrates the relationship of those factors with customer satisfaction and loyalty. As a result, the important factors for service recovery are an immediate compensation, truthfulness, reaction and assurance

• International Journal of Quality Innovation
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• 제8권1호
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• pp.76-86
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• 2007

This paper reports on a study investigating key attributes of service recovery strategies in internet shopping mall. In theses day, service recovery has received important attention in the service operation management literature. Service recovery involves those actions designed to resolve problems, alter negative attitudes of dissatisfied consumers and to ultimately retain these customers. The study examined that service recovery strategies (apology, compensation) impact on the customer satisfaction. And customer satisfaction impacts on customer loyalty with SEM (Structural Equation Modeling). This study can be used a strategic implication for internet shopping mall managers to develop successful service recovery strategies.

• 대한안전경영과학회지
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• 제9권6호
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• pp.97-103
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• 2007

This paper reviewed the relationship among internal marketing, service quality and customer satisfaction, and the mediating effect of service quality. Based on the responses from 163 hotel employees and 489 customers who encountered them, the results of hierarchical regressional analysis showed that all internal marketing factors have positive relationships with service quality, and service quality has positive relationship with customer satisfaction. Also, service quality has mediating effect between four internal marketing factors(education, compensation, delegation of authority, and internal communication) and customer satisfaction.

• 전력전자학회논문지
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• 제26권2호
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• pp.90-95
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• 2021

In contrast to AC grounding systems, the ground electrode in DC systems continuously maintains positive or negative polarity. Ground electrodes with (+) polarity proceeds by oxidation reaction. Thus, the DC current should flow opposite to the polarity of the leakage current flowing through the (+) ground electrode by using a compensation electrode, and the current flowing through the (+) ground electrode can be 0A. However, according to protecting the (+) ground electrode, the compensation electrode corrodes and gets damaged. Thus, the (+) ground electrode must be protected from corrosion, and the service life of the compensation electrode must be extended. As an alternative, the average value of the current flowing through the compensation electrode should be equal with the value of the leakage current flowing through the (+) ground electrode by using the square waveform. Throughout the experiment, the degree of corrosion on the compensation electrode is analyzed by the frequency of the compensation electrode for a certain time. In the experiment, the frequencies of the square waveform are considered for 0.1, 1, 10, 20, 50, 100 Hz, and 1 kHz. Through experiments and analysis, the optimal frequency for reducing the electrolytic damage of the (+) electrode and compensation electrode in an LVDC grounding environment is determined.

• 의료법학
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• 제11권1호
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• pp.59-84
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• 2010

Medical practice is characterized by various physiological response and uncapacity of prediction, therefore when medical accident occur it's hard to prove medical professionals' mistake. Though medical accident by medical professionals' mistake will be compensated anyhow, about irresistible medical accidents, no one should be not bound to compensate, victims get into very difficult situation. So, the nation don't negligent irresistible medical accidents but compensate anyway. As in the past, to the legal principle's constitution of irresistible medical accidents, theory of liability without fault was adapted, and it was said this theory was illogical in theory of liability with fault. But the subject of compensation to irresistible medical accidents is nation, nation don't participate in medical treatment therefore there is no room to occur mistake. And it is not reasonable to regard medical agency as a truster of public service, to cast to it responsibility of medical accidents. The problem of compensation to irresistible medical accidents is understood under the theory of social compensation. Social compensation is consisted of compensation to sacrifice and contribution to nation and society and compensation to sacrifice revealed under danger, the compensation to irresistible medical accidents belongs to the latter. This is near to concept of relief, is applied to national compensation system supplementarily, and compensation have no option but to compensate minimum. And there are not relation between national compensation system of irresistible medical accidents and proof liability transposition and theory of liability with out fault, merely in side of sharing responsibility burden between medical treater and victim, it is reasonable to discuss transportation of proof liability and compulsive liability insurance together.

• 대한임상검사과학회지
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• 제49권3호
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• pp.214-219
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• 2017

탄광부진폐증(CWP)과 만성폐쇄성폐질환(COPD)은 석탄분진에 노출되는 탄광부의 폐에서 나타나는 만성적 폐 염증의 특성을 가진다. 이번 연구의 목적은 대조군 27명, CWP 40명, COPD를 동반한 CWP 30명 등 총97명을 대상으로 염증지표로서 혈청 중의 LD와 CRP 수준을 비교하고자 하였다. 혈청 중의 LD 평균 농도(165.7 vs 184.6 U/L, p=0.016)와 CRP 평균 농도(0.08 vs 0.15 mg/dL, p=0.002)는 CWP군에서 유의하게 높았다. 혈청 중의 CRP 평균 농도(0.10 vs 0.19 mg/dL, p=0.008)는 COPD군에서 높았다. 연령을 통제한 공분산분석에서, 혈청 중 CRP 평균 농도는 대조군, CWP군 및 CWP+COPD군 간에 통계적으로 유의한 차이가 있었으며(0.07 vs 0.13 vs 0.19 mg/dL, p=0.005), CWP+COPD 군의 혈청 CRP 평균 농도가 대조군보다 유의하게 높았다(p=0.001). 이러한 결과는 높은 수준의 혈청 중 CRP는 탄광부 이직근로자에서의 CWP 및 COPD와 관련이 있는 것으로 보인다.

• 한국산업보건학회지
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• 제29권3호
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• pp.289-297
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• 2019

Objectives: To identify the positive rate of and the risk factors associated with latent tuberculosis infection(LTBI) in mine workers, the objectives of the present study evaluated those among former mine workers. Methods: Between January 2015 and May 2017, former male mine workers who had been subjects for epidemiology research for work-related chronic obstructive pulmonary disease(COPD) and had received QuantiFERON-$TB^{(R)}$ Gold In-Tube(QFT-GIT) from the Institute of Occupation and Environment(IOE) under Korea Workers' Compensation and Welfare Service(KCOMWEL) were selected as the study subjects. To identify significant variables for increased risk of LTBI, logistic regression analysis was performed. Results: A total of 736 male former mine workers were selected as study subjects. The positive rate of LTBI among subjects was 69.2%(509/736). The current smoking[odds ratio(OR), 2.3; 95% confidence interval(CI), 1.1-4.9], COPD(OR, 1.4; 95% CI, 0.9-2.3), department loading(OR, 1.8; 95% CI, 0.9-3.4) and mining(OR, 1.5; 95% CI, 0.9-2.5), and working duration of over 20(OR, 1.6; 95% CI, 0.9-3.1) and over 30 years(OR, 2.2; 95% CI, 0.9-4.9) were associated with increased risk of LTBI. The interferon-gamma(IFN-${\gamma}$) level after stimulation with Mycobacterium tuberculosis(MTB)-specific antigens showed a significantly negative correlation with age(r=-0.126). Conclusions: The present study determined that the high positive rate of LTBI among mine workers was associated with not only the host factors but also the occupational exposure to mine dust.

• 한국산업보건학회지
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• 제34권1호
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• pp.57-66
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• 2024

Objective: Chronic obstructive pulmonary disease (COPD) is characterized by progressive airflow obstruction that is only partly reversible, inflammation in the airways, and systemic effects. This study aimed to investigate the association between low peripheral oxygen saturation levels (SpO₂), and composite indices predicting death in male patients with (COPD). Method: A total of 140 participants with post-bronchodilator FEV₁/FVC ratio less than 0.7 were included. Three composite indices (ADO, DOSE, BODEx) were calculated using six variables such as age (A), airflow obstruction (O), body mass index (B), dyspnea (D), exacerbation history (E or Ex), and smoking status (S). Severity of airflow limitation was classified according to Global Initiative for Obstructive Lung Disease (GOLD) guidelines. SpO₂ was measured by pulse oximetry, and anemia and iron deficiency were assessed based on blood hemoglobin levels and serum markers such as ferritin, transferrin saturation, or soluble transferrin receptor. Results: Participants with low SpO₂ (<95%) showed significantly lower levels of %FEV₁ predicted (p=0.020) and %FEV₁/FVC ratio (p=0.002) compared to those with normal SpO₂ levels. The mMRC dyspnea scale (p<0.001) and GOLD grade (p=0.002) showed a significant increase in the low SpO₂ group. Receiver Operating Characteristic analysis revealed higher area under the curve for %FEV₁ (p=0.020), %FEV₁/FVC(p=0.002), mMRC dyspnea scale (p=0.001), GOLD grade (p=0.010), ADO (p=0.004), DOSE (p=0.002), and BODEx (p=0.011) in the low SpO₂ group. Conclusion: These results suggest that low SpO₂ levels are related to increased airflow limitation and the composite indices of COPD.