• 제목/요약/키워드: ${\Re}_a$ operator

검색결과 44건 처리시간 0.025초

The Study on the Effect of Experience Values of Chinese Coffee Shop on the Intent of Revisiting of Consumers: Focusing on the Mediation Effect of Emotional Responses

  • KANG, Min-Jung;WAN, Yeo-Sun;HWANG, Hee-Joong
    • 유통과학연구
    • /
    • 제17권11호
    • /
    • pp.47-52
    • /
    • 2019
  • Purpose: This study specifically discusses why coffee shop customers want to revisit coffee shops. In addition, we would like to verify the mediated effect of the emotional reaction in relation to the influence of the experience values of the Chinese coffee shop on the re-visit of the coffee shop. Research design, data and methodology: Regression and reliability analyses were conducted. Simple regression was used for stock price verification, and the bootstrap method of model4 of Hayes was performed for the intermediate hypothesis verification. Results: This study confirmed that the experience values of coffee shops (entertainment, aesthetic, economic efficiency, and service excellence) have a significant influence on customers' intention to revisit coffee shops. Conclusions: Managers can check that the level of revisit by customers is increased by increasing the elements of experience value. In addition, studies have shown that the customer's emotional reactions play a significant mediating role in the relationship between the value of the experience and the customer's intention to revisit the coffee shop. This suggests that the coffee shop operator should focus on the emotional response of its customers and devise strategies to ensure that the value of the experience is connected to the intent of revisiting.

노출감시체계 구축을 위한 작업환경측정 정보 표준화 (Standardization of work environment measurement information for constructing exposure surveillance system)

  • 최상준;정지연;임성국;임대성;고동희;박동욱;박윤경;김소연;정은교
    • 한국산업보건학회지
    • /
    • 제29권3호
    • /
    • pp.322-335
    • /
    • 2019
  • Objectives: The goal of this study is to standardize industry, process, and job within work environment measurement information. Methods: We selected 180 work environment measurement reports on 30 industries from a database monitored from 2014 to 2016 by the Korea Industrial Health Association. Ten industrial hygienists, each with over five years of experience in measurement, conducted a primary standardization of 180 reports. Two professional industrial hygienists with more than 20 years of experience each reviewed and revised the results of the primary standardization. We also examined the validity on the usefulness of the standardized database by the two industrial hygienists. Results: The final standardization results were classified into eight major categories, 23 sub-major categories, 39 minor categories, 53 unit categories and 70 sub-unit categories in the Korean Standard Industrial Classification (KSIC) 10th revision. A total of 161 processes were standardized, and there were 148 processes with K2B codes. Standard job was coded into 13 job groups including operator, automobile maintenance, nurse, maintenance, manager, excavating machine operator, forklift driver, radiologist, clinical pathologist, signer, researcher, kitchen assistant, and concrete reinforcement ironworker. Conclusions: Although the standardized information in this study may be only a part of the total information, it can be useful for improvement of the K2B system. Additional research is needed for an ongoing clean-up of data in the K2B and re-calibration and reclassification of standard processes until the future national exposure monitoring system is fully established.

SiRENE: A new generation of engineering simulator for real-time simulators at EDF

  • David Pialla;Stephanie Sala;Yann Morvan;Lucie Dreano;Denis Berne;Eleonore Bavoil
    • Nuclear Engineering and Technology
    • /
    • 제56권3호
    • /
    • pp.880-885
    • /
    • 2024
  • For Safety Assisted Engineering works, real-time simulators have emerged as a mandatory tool among all the key actors involved in the nuclear industry (utilities, designers and safety authorities). EDF, Electricité de France, as the leading worldwide nuclear power plant operator, has a crucial need for efficient and updated simulation tools for training, operating and safety analysis support. This paper will present the work performed at EDF/DT to develop a new generation of engineering simulator to fulfil these tasks. The project is called SiRENE, which is the acronym of Re-hosted Engineering Simulator in French. The project has been economically challenging. Therefore, to benefit from existing tools and experience, the SiRENE project combines: - A part of the process issued from the operating fleet training full-scope simulator. - An improvement of the simulator prediction reliability with the integration of High-Fidelity models, used in Safety Analysis. These High-Fidelity models address Nuclear Steam Supply System code, with CATHARE thermal-hydraulics system code and neutronics, with COCCINELLE code. - And taking advantage of the last generation and improvements of instructor station. The intensive and challenging uses of the new SiRENE engineering simulator are also discussed. The SiRENE simulator has to address different topics such as verification and validation of operating procedures, identification of safety paths, tests of I&C developments or modifications, tests on hydraulics system components (pump, valve etc.), support studies for Probabilistic Safety Analysis (PSA). etc. It also emerges that SiRENE simulator is a valuable tool for self-training of the newcomers in EDF nuclear engineering centers. As a modifiable tool and thanks to a skillful team managing the SiRENE project, specific and adapted modifications can be taken into account very quickly, in order to provide the best answers for our users' specific issues. Finally, the SiRENE simulator, and the associated configurations, has been distributed among the different engineering centers at EDF (DT in Lyon, DIPDE in Marseille and CNEPE in Tours). This distribution highlights a strong synergy and complementarity of the different engineering institutes at EDF, working together for a safer and a more profitable operating fleet.

Prostate cancer in workers exposed to night-shift work: two cases recognized by the Korean Epidemiologic Investigation Evaluation Committee

  • Sungkyun Park;Seongwon Ma;Hoekyeong Seo;Sang Gil Lee;Jihye Lee;Shinhee Ye
    • Annals of Occupational and Environmental Medicine
    • /
    • 제35권
    • /
    • pp.52.1-52.13
    • /
    • 2023
  • Background: In 2019, the International Agency for Research on Cancer re-evaluated the carcinogenicity of night-shift work and reported that there is limited evidence that night-shift work is carcinogenic for the development of prostate cancer. Therefore, in 2020 and 2021, the Korean Epidemiologic Investigation Evaluation Committee concluded that 2 cases of prostate cancer were occupational diseases related to the night-shift work. Here, we report the 2 cases of prostate cancer in night-shift workers which were first concluded as occupational diseases by the Korean Epidemiologic Investigation Evaluation Committee. Case presentation: Patient A: A 61-year-old man worked as a city bus driver for approximately 17 years, from 2002 to 2019, and was exposed to night-shift work during this period. In March 2017, the patient was diagnosed with high-grade prostate cancer through core-needle biopsy after experiencing stinging pain lasting for 2 months. Patient B: A 56-year-old man worked as an electrician and an automated equipment operator in a cement manufacturing plant for 35 years from 1976 to 2013 and was exposed to night-shift work during this period. In 2013, the patient was diagnosed with high-grade prostate cancer through core needle biopsy at a university hospital because of dysuria that lasted for 6 months. Conclusions: The 2 workers were diagnosed with high-grade prostate cancer after working night shifts for 17 and 35 years respectively. Additionally, previous studies have reported that high-grade prostate cancer has a stronger relationship with night-shift work than low or medium-grade prostate cancer. Therefore, the Korean Epidemiologic Investigation Evaluation Committee concluded that night-shift work in these 2 patients contributed to the development of their prostate cancer.

Angioembolization performed by trauma surgeons for trauma patients: is it feasible in Korea? A retrospective study

  • Soonseong Kwon;Kyounghwan Kim;Soon Tak Jeong;Joongsuck Kim;Kwanghee Yeo;Ohsang Kwon;Sung Jin Park;Jihun Gwak;Wu Seong Kang
    • Journal of Trauma and Injury
    • /
    • 제37권1호
    • /
    • pp.28-36
    • /
    • 2024
  • Purpose: Recent advancements in interventional radiology have made angioembolization an invaluable modality in trauma care. Angioembolization is typically performed by interventional radiologists. In this study, we aimed to investigate the safety and efficacy of emergency angioembolization performed by trauma surgeons. Methods: We identified trauma patients who underwent emergency angiography due to significant trauma-related hemorrhage between January 2020 and June 2023 at Jeju Regional Trauma Center. Until May 2022, two dedicated interventional radiologists performed emergency angiography at our center. However, since June 2022, a trauma surgeon with a background and experience in vascular surgery has performed emergency angiography for trauma-related bleeding. The indications for trauma surgeon-performed angiography included significant hemorrhage from liver injury, pelvic injury, splenic injury, or kidney injury. We assessed the angiography results according to the operator of the initial angiographic procedure. The term "failure of the first angioembolization" was defined as rebleeding from any cause, encompassing patients who underwent either re-embolization due to rebleeding or surgery due to rebleeding. Results: No significant differences were found between the interventional radiologists and the trauma surgeon in terms of re-embolization due to rebleeding, surgery due to rebleeding, or the overall failure rate of the first angioembolization. Mortality and morbidity rates were also similar between the two groups. In a multivariable logistic regression analysis evaluating failure after the first angioembolization, pelvic embolization emerged as the sole significant risk factor (adjusted odds ratio, 3.29; 95% confidence interval, 1.05-10.33; P=0.041). Trauma surgeon-performed angioembolization was not deemed a significant risk factor in the multivariable logistic regression model. Conclusions: Trauma surgeons, when equipped with the necessary endovascular skills and experience, can safely perform angioembolization. To further improve quality control, an enhanced training curriculum for trauma surgeons is warranted.

Fibromyalgia diagnostic model derived from combination of American College of Rheumatology 1990 and 2011 criteria

  • Ghavidel-Parsa, Banafsheh;Bidari, Ali;Hajiabbasi, Asghar;Shenavar, Irandokht;Ghalehbaghi, Babak;Sanaei, Omid
    • The Korean Journal of Pain
    • /
    • 제32권2호
    • /
    • pp.120-128
    • /
    • 2019
  • Background: We aimed to explore the American College of Rheumatology (ACR) 1990 and 2011 fibromyalgia (FM) classification criteria's items and the components of Fibromyalgia Impact Questionnaire (FIQ) to identify features best discriminating FM features. Finally, we developed a combined FM diagnostic (C-FM) model using the FM's key features. Methods: The means and frequency on tender points (TPs), ACR 2011 components and FIQ items were calculated in the FM and non-FM (osteoarthritis [OA] and non-OA) patients. Then, two-step multiple logistic regression analysis was performed to order these variables according to their maximal statistical contribution in predicting group membership. Partial correlations assessed their unique contribution, and two-group discriminant analysis provided a classification table. Using receiver operator characteristic analyses, we determined the sensitivity and specificity of the final model. Results: A total of 172 patients with FM, 75 with OA and 21 with periarthritis or regional pain syndromes were enrolled. Two steps multiple logistic regression analysis identified 8 key features of FM which accounted for 64.8% of variance associated with FM group membership: lateral epicondyle TP with variance percentages (36.9%), neck pain (14.5%), fatigue (4.7%), insomnia (3%), upper back pain (2.2%), shoulder pain (1.5%), gluteal TP (1.2%), and FIQ fatigue (0.9%). The C-FM model demonstrated a 91.4% correct classification rate, 91.9% for sensitivity and 91.7% for specificity. Conclusions: The C-FM model can accurately detect FM patients among other pain disorders. Re-inclusion of TPs along with saving of FM main symptoms in the C-FM model is a unique feature of this model.

지상파방송과 케이블방송 간에 지상파채널 재송신 대가 산정방안 (A Method for Estimating Retransmission Fee for Terrestrial Broadcasting Channels between Terrestrial Television Systems and Cable TV System Operators)

  • 문명석;이송희;최성진
    • 방송공학회논문지
    • /
    • 제21권5호
    • /
    • pp.689-703
    • /
    • 2016
  • 지상파방송사와 케이블SO 간에 지상파채널 재송신 대가 분쟁이 2007년부터 현재까지 진행 중이고, 특단의 방법이 없는 한 미래에도 계속될 전망이다. 따라서 본 논문에서는 지상파채널 재송신 대가 산정을 위해 두 가지 방법을 제시하였다. 첫째는 수익배분방법으로 지상파와 케이블이 각자 기여하는 정도에 대해 정산을 통해 대가를 산정하고, 둘째는 지상파채널에 대한 대가를 케이블PP의 프로그램사용료 기준으로 산정하는 방법이다. 또한 수익배분방식과 프로그램사용료 방법을 기준으로 정액제와 정률제의 두 가지 방식을 적용하여 재송신 대가를 제시하였다.

일방향 함수와 XOR을 이용한 효율적인 그룹키 관리 프로토콜: ELKH (ELKH, Efficient Group Key Management Protocol Using One-Way Function and XOR)

  • 권정옥;황정연;김현정;이동훈;임종인
    • 정보보호학회논문지
    • /
    • 제12권6호
    • /
    • pp.93-112
    • /
    • 2002
  • 다수의 다양한 구성원들로 구성된 멀티캐스트 그룹은 매우 변동적이며, 이로 인하여 구성원들이 매 세션마다 빈번히 추가되거나 삭제된다. 따라서 새로운 세션을 시작하기 위해서는 세션키가 효율적으로 갱신되고 분배되어야 한다. 본 논문에서는 일방향 함수(one-way function)와 XOR 연산자를 이용해서 효율적이면서도 안전하게 그룹키를 갱신하고 분배할 수 있는 그룹키 관리 프로토콜 ELKH(Efficient Logical Key Hierarchy)를 소개한다. LKH에 기반한 문헌의 키 관리 프로토콜들에서는 안전하지 않은 멀티캐스트 채널을 통해 정당한 구성원들에게 키 갱신 메시지를 전달해야 하는 경우에 특정 암호 알고리즘을 필요로 한다. 하지만 본 논문에서 제시하는 프로토콜은 특정 암호 알고리즘 대신에 일방향 함수를 이용하여 메시지를 은닉하는 새로운 접근방법이다. 본 논문의 주된 결과는 ELKH가 $EHBT^{[12]}$와 비교해, 키 갱신 메시지의 크기가 증가되지 않으면서 키 갱신 속도가 더 빠르다는 것이다. 그리고 주어진 일방향 함수의 안전성에 기반해서 ELKH 프로토콜이 forward secrecy와 backward secrecy를 만족한다는 것을 증명한다.

대용량 3차원 포인트 클라우드의 탐색을 위한 메모리 효율적인 옥트리의 설계 (Design of Memory-Efficient Octree to Query Large 3D Point Cloud)

  • 한수희
    • 한국측량학회지
    • /
    • 제31권1호
    • /
    • pp.41-48
    • /
    • 2013
  • 본 연구는 대용량 3차원 포인트 클라우드의 탐색을 위한 메모리 효율적인 옥트리를 설계하는 것을 목표로 한다. 이를 위하여 C++ 언어로 구현된 옥트리 노드의 구성요소 중 최소 경계 입방체 좌표 정보 등을 위한 변수를 제거하는 대신, 부모 노드에서 자식 노드 접근시 최소 경계 입방체 좌표를 계산하여 전달하였다. 아울러 자식 노드 등의 생성시마다 new 연산자를 사용하는 대신, 수도 트리와 정식 트리를 생성하는 이중적인 과정을 통해 노드 등을 배열로 미리 선언함으로서 메모리 효율성을 더욱 개선하였다. 1800만개 이상의 포인트로 구성된 실제 포인트 클라우드를 대상으로 트리를 구성하고 인접 포인트를 탐색하는 실험을 수행하였다. 최소 경계 입방체 좌표 정보를 노드에 저장하는 경우와 비교한 결과 메모리 사용량과 탐색 속도의 트레이드오프가 존재하지만 제안한 방식이 비교군보다 메모리 효율적이어서 대용량 포인트 클라우드에 적용할 수 있는 대안임을 확인할 수 있었다.

커넥티드 카의 기술 (The Technology of Connected Car)

  • 심현보
    • 한국정보통신학회논문지
    • /
    • 제20권3호
    • /
    • pp.590-598
    • /
    • 2016
  • 자동차와 이동통신기술이 융합된 커넥티드 카 산업이 새로운 블루오션으로 주목받고 있고, 휴대용 전자기기(스마트폰, 태블릿 PC, MP3 플레이어 등)와 자동차를 연결한 각종 인포테인먼트(infotainment) 서비스들도 빠르게 성장하고 있다. 커낵티드 카란 자동차가 주변과 실시간으로 소통하며 운전자에게 안전과 편의를 제공한다는 개념으로 차량 연결성(Connectivity)을 강조하고 자동차에 사물인터넷(IoT)을 채용하여 플랫폼으로 활용, 현재는 실시간 내비게이션, 주차 보조기능, 원격 차량제어 및 관리 서비스뿐만 아니라 이메일, 멀티미디어 스트리밍, SNS 등 엔터테인먼트 서비스를 지원하고 있다. 지능형 자동차 네트워크는 MANET(Mobile Ad Hoc Network)의 한 종류로 도로 상의 자동차들의 안전한 운행 및 운행 효율성 제고 등을 위해 연구되고 있다.