• 한국재료학회지
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• 제32권3호
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• pp.146-152
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• 2022

One disadvantage of deep cycle flooded lead-acid batteries is increasing water loss caused by use of (+) Pb-Sb / (-) Pb-Sb alloy grid. Water loss is generated by the emission of hydrogen gas from the (-) electrode during battery charging. In this paper, we maintain cycle life aspect through the development of hybrid flooded lead-acid batteries to which a (+) Pb-Sb / (-) Pb-Ca grid is applied and deal with the improvement of water loss. The amount of water loss compared to that of the (-) Pb-Sb grid decreased when Ca was added to the (-) Pb grid. For the (-) Pb-Ca grid, it was confirmed that the time to reach 0.0 V, at which water decomposition occurs, was increased compared to that of the (-) Pb-Sb grid at the NPV (Negative Potential Voltage). In the cycle life test conducted with the BCI (Battery Council International) standard, compared to the (+) Pb-Ca grid, the (+) Pb-Sb grid increased the life cycle of the batteries and the (+) Pb-Ca grid showed an early end of life due to PbO corrosion layer generation, as determined through SEM / EDS and Tear Down analysis. In conclusion, by addition of Sb to (+) Pb grid and Ca to (-) Pb grid, we developed a hybrid flooded lead-acid battery that meets user requirements to improve water loss characteristics and preserve cycle life characteristics.

• Korean Circulation Journal
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• 제54권3호
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• pp.140-153
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• 2024

Background and Objectives: Although a single-lead electrocardiogram (ECG) patch may provide advantages for detecting arrhythmias in outpatient settings owing to user convenience, its comparative effectiveness for real-time telemonitoring in inpatient settings remains unclear. We aimed to compare a novel telemonitoring system using a single-lead ECG patch with a conventional telemonitoring system in an inpatient setting. Methods: This was a single-center, prospective cohort study. Patients admitted to the cardiology unit for arrhythmia treatment who required a wireless ECG telemonitoring system were enrolled. A single-lead ECG patch and conventional telemetry were applied simultaneously in hospitalized patients for over 24 hours for real-time telemonitoring. The basic ECG parameters, arrhythmia episodes, and signal loss or noise were compared between the 2 systems. Results: Eighty participants (mean age 62±10 years, 76.3% male) were enrolled. The three most common indications for ECG telemonitoring were atrial fibrillation (66.3%), sick sinus syndrome (12.5%), and atrioventricular block (10.0%). The intra-class correlation coefficients for detecting the number of total beats, atrial and ventricular premature complexes, maximal, average, and minimal heart rates, and pauses were all over 0.9 with p values for reliability <0.001. Compared to a conventional system, a novel system demonstrated significantly lower signal noise (median 0.3% [0.1-1.6%] vs. 2.4% [1.4-3.7%], p<0.001) and fewer episodes of signal loss (median 22 [2-53] vs. 64 [22-112] episodes, p=0.002). Conclusions: The novel telemonitoring system using a single-lead ECG patch offers performance comparable to that of a conventional system while significantly reducing signal loss and noise.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.957-961
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• 1997

In this paper, an assessment has been proceeded about component technology that stamping car panel can be designed and manufactured efficiently. Also this study investigated srandard model of CAD/CAM system in production process of automobile dies. Recently, motor companies are doing their best to increase productivity and to reduce production time. So to develop user-friendly and effective standard model of CAD/CAM system is very important. The obtained results will lead to the reductions in lead time and man-hour required for the design and manufacture of the automobile dies.

• 품질경영학회지
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• 제25권1호
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• pp.56-68
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• 1997

The object of multiresponse optimization is to determine conditions on hte independent variables that lead to optimal or nearly optimal values of the response variables. Derringer and Suich (1980) extended Harrington's (1965) procedure by introducing more general transformations of the response into desirability functions. The core of the desirability a, pp.oach condenses a multivariate optimization into a univariate one. But because of the subjective nature of this a, pp.oach, inexperience on the part of the user in assessing a product's desirability value may lead to inaccurate results. To compensate for this defect, a weighted desirability function is introduced which takes into consideration the vriances of the responses.

• 한국생산제조학회지
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• 제7권3호
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• pp.85-91
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• 1998

In this paper an assessment has been proceeded about component technology that stamping car panel can be designed and manufactured efficiently. Also this study investigate standard model of CAD/CAM system in production process of automobile dies, Recently, motor companies are doing their best to increase productivity and to reduce production time. So to develop user-friendly and effective standard model of CAD/CAM system is very important. The cbtained results will lead to the reductions in lead time and man-hour required for the design and manufacture of the automobile dies.

• Journal of Smart Tourism
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• 제2권4호
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• pp.35-43
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• 2022

Tourism businesses use chat services to provide immediate customer support and to help users navigate within a website, but there are more outcomes of this interaction that should be examined. The current study aimed to discover if the online travel chat service quality and information value of the online travel chat service lead to user satisfaction with the service and visit intention to a recommended destination by Korea Tourism Organization's 1330 Live Chat. The results indicate that information value (functional and innovation) and online travel chat service quality (reliability, assurance, and security) lead to satisfaction with the live chat service and visit intention to a recommended destination. The results can benefit practitioners who want to expand and improve their customer service interaction and recommendations, and to scholars who study the relationship between customer services in tourism recommendation and sales context.

• 정보교육학회논문지
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• 제17권2호
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• pp.211-224
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• 2013

본 연구의 목적은 ET(eye-tracking)를 활용하여 교육용 게임의 UI(user interface)를 구성할 때, UX(user experience)관점에서 효과적 구성 방안을 찾는데 있다. 실험 자료는 중학교 힘과 운동에 관련된 게임이었고 안구운동 데이터를 수집하기 위해 SMI(SensoMotoric Instruments)사의 iView X TM RED 120Hz를 사용하였다. 연구 결과는 다음과 같다. 첫째, 교육용 게임에서 빠른 시각적 주의를 이끌기 위한 요소는 UI의 가운데에 배치해야 한다. 둘째, 캐릭터의 속성을 변경하는 버튼과 그 속성에 대한 정보는 서로 근접한 위치에 배치해야 한다. 셋째, 학습 퀴즈는 UI의 위쪽에 위치할 때 더 빠른 시각적 주의를 이끌었다. 넷째, 처음 UI에 다른 UI를 겹쳐서 제시하였을 때 완전히 겹쳐지지 않은 부분의 처음 UI에서도 응시가 발생하였다.

• 재활복지공학회논문지
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• 제9권2호
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• pp.121-128
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• 2015

본 논문에서는 보청기 사용자가 본인의 청력손실도를 청력검사를 통해 스스로 측정하여 보청기/이어폰에 피팅이 가능한 어플리케이션을 개발하였다. 개발된 어플리케이션은 청력검사와 피팅을 통한 증폭 기능을 동시에 제공한다는 점에서 청력검사 기능 혹은 증폭 기능만 갖춘 기존의 어플리케이션들과 차이점이 있다. 개발된 어플리케이션의 청력검사는 기본검사와 정밀검사를 제공하며, 두 검사 모두 순음청력검사방법을 사용하여 6개의 주파수에서 청력손실도를 측정한다. 기본검사는 난청인의 청력손실도 경향을 이용하여 검사 과정을 단축시킴으로써 짧은 검사 시간을 제공하며, 정밀검사는 모든 주파수 영역에서 이중 확인을 통해 보다 정확한 결과를 제공한다. 청력검사의 결과로 얻은 주파수별 청력손실도를 기반으로 음성 명료도를 높이기 위해 입력신호는 보청기 피팅 방법 중 하나인 NAL-NL1 방법을 통하여 증폭된다. 또한 환경설정기능을 통하여 저장된 설정 값을 불러와 바로 적용할 수 있는 기능을 제공한다. 이처럼 개발된 어플리케이션은 사용자 스스로 피팅 과정을 진행할 수 있기에 피팅을 위해 주기적으로 병원이나 전문센터를 방문하였던 기존의 불편함을 간편화하여 보청기를 사용하는 난청인의 수를 증가 시킬 것으로 전망된다.

• 설비공학논문집
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• 제27권10호
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• pp.527-536
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• 2015

Studies for the reduction of lighting energy have been done using technologies such as user and location awareness. However, the focus of current research on location-based lighting control has been on energy reduction, which can lead to other issues including an imbalance in indoor illumination. This study proposes a lighting control system applying general illumination and technology for user and location awareness. The proposed lighting control system reduced lighting energy by 72.1%, 66.5% and 62.3% for 1, 2 and 3 users, respectively, compared to the On/Off lighting control system. This lighting control system causes an increase in lighting energy of 35.8% and 10.9% for 1 and 2 users compared to the lighting control system with user and location awareness, while a reduction of 9.4% was seen for 3 users. This means that the proposed system provides more effective energy reduction for a room with multiple occupants as it is based on the general lighting control scheme. The lighting control system applying general illumination and technology of user and location awareness improved the uniformity factor by 32.0%, 39.4% and 33.4% for 1, 2 and 3 users, respectively.

• 디지털융복합연구
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• 제17권8호
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• pp.379-384
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• 2019

본 연구는 온라인 설문조사 사용자 경험 연구이다. 온라인 설문조사의 활용과 발전을 위해 사용자 측면의 연구를 하는 것에 목적이 있다. 연구 방법으로는 네이버와 구글의 사용 경험이 없는 피험자 8명을 대상으로 사용자 경험에 영향을 미치는 요인을 태스크를 통한 수행 평가, 씽크얼라우드, 피터 모빌의 허니콤 모형을 이용한 설문, 심층 인터뷰를 통해 분석하였다. 연구 결과, 네이버는 유용성, 사용성, 매력성, 검색성이 높으며 구글은 접근성과 유연성이 우수하다는 것을 확인할 수 있었다. 특히 인터페이스 메뉴 카테고리의 재분류와 이동으로 사용성을 높이고 기능을 쉽게 찾기 위한 개선안이 필요하다는 시사점을 도출했다. 본 연구는 기존에 연구되지 않았던 온라인 설문조사 사용자 경험으로 사용성 개선의 방향을 예측하고 사용자 측면에 도움을 줄 수 있다. 본 연구를 바탕으로 추후 온라인 설문조사의 사용성이 개선되고, 다양한 관련 연구가 진행될 것을 기대한다.