• Title/Summary/Keyword: Wake-up

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The Impact of Food Delivery Apps on Urban Hotels after the Pandemic and its Implications

  • Eungoo KANG
    • 산경연구논집
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    • 제15권4호
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    • pp.11-18
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    • 2024
  • Purpose: The primary purpose of this research is to investigate the multidisciplinary effect of food delivery apps (FDAs) in urban hotels in the wake of the lockdown due to Covid-19 pandemic. Specifically, the study aims: To explore and scrutinize the primary shifts in customer behavior and preferences in modern urban hotels, and to explore and scrutinize the primary shifts in customer behavior and preferences in modern urban hotels. Research design, data and methodology: This study conducted a systematic literature review to gather evidence of the FDA's effect on customer behavior and the hospitality industry during the Covid-19 pandemic. Complying with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) principles guarantees a structured and transparent method to search the literature and its analysis. Results: The result based on the systematic review has indicated that the booming business of food delivery at home companies and changing consumer tastes prove the FDA's growing circuit in the hotel industry, thus demonstrating their ability and power to adapt to changing trends. Conclusions: Therefore, this study concludes that using FDA's platform, future hospitality managers have to focus on agility in operations, innovation, and technology integration to keep up with changing consumer trends and market conditions.

Seismic Retrofit after 921 Earthquake

  • Tsai, C.S.
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2000년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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    • pp.18-20
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    • 2000
  • At 1:47 a.m, local time on September 21, 1999, a strong earthquake measured 7.3 on the Richter scale struck central Taiwan evoking another two earthquakes a few seconds late to wake up unprepared people of this small island. It caused 2,465 people killed 11,305 injured about 10,000 buildings collapsed and around 41,000 severely damaged, The major concerns after the earthquake are how to have learned from this natural disaster and how to rebuild earthquake-proof buildings without rendering up safety within reasonable costs. Inevitable actions for redrafting the building codes have been taken to re-strengthen the existing and new structures. Structural analysis tools and computer programs adopted by most practicing engineers have been re-examined to take into account the effects of the vertical component of ground shakings on structural responses. Most private structures were repaired by traditional methods without considering upgrading seismic resistibility because of economical reasons. Buildings open to the public are under consideration possibly enforced by making regulations to be upgraded to satisfy revised building codes. In addition new rehabilitation technologies such as structural control have been moving much faster than before and have become accepted by the public due to frequent reports by media and specialists. Building codes related to base isolators and energy absorption systems are still under legislation and expected to be published soon. Most of the new structures under construction designed by the building codes promulgated before the earthquake have been reconsidered to comply with the new codes even though it is not compulsory. Efforts have been made by the government engineering and research communities and universities in an attempt to reduce structural damage for future earthquakes and to construct if possible Taiwan as an earthquake-proof island.

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802.11 Ad-Hoc 네트웍에서 Power Save Mechanism을 개선한 DAPSM 알고리즘 (Dynamic ATIM Power Saving Mechanism(DAPSM) in 802.11 Ad-Hoc Networks)

  • 박재현;이장수;김성천
    • 정보처리학회논문지C
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    • 제14C권6호
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    • pp.475-480
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    • 2007
  • 최근 무선 네트워킹 장치들이 등장 하면서 제한된 배터리에 의존하는 무선 호스트들의 전력 절감은 중요한 이슈 가 되었다. 특히 Ad-Hoc에서 배터리는 제한된 에너지를 제공하기 때문에 무선 호스트에 의해서 소모되어지는 에너지의 양을 감소시키기 위한 기술은 대단히 중요하다. 특히 MAC 과 라우팅 에서 전력 절감을 이루기 위한 논문들이 기존에 발표 되었다. 이 논문에서는 IEEE 802.11 표준의 DCF(Distributed Coordination Function)에서의 전력 절감 메카니즘을 향상 시킨 논문 이다. DCF를 위한 IEEE 802.11 전력 절감 메카니즘에서는 비콘 간격 이라는 시간으로 나누어지며 또한 이러한 각각의 비콘 간격이 시작될 때 각각의 노드들은 ATIM 창 동안 깨어 있어야 한다. 물론 모든 노드는 같은 시간에 깨어 있기 위해서는 동기화 되는 것이 필요하다. ATIM 창 동안 노드들은 비콘 기간 동안 깨어 있는 상태로 있을 것인지를 결정하기 위해서 control packet을 교환 한다. 이러한 ATIM 창 크기는 각각의 노드들의 전력 절감에 상당한 영향을 미친다. 따라서 이 논문은 ATIM 창 크기를 동적으로 증감시켜서 보다 에너지 효율을 발휘 하고자 하는 논문이다.

불면증에 자하거(紫河車) 약침(藥針)을 응용한 1례 (The Case of regulation of Insomnia with Jahageo Herbal acupuncture)

  • 장현호;두인선;이대용;이승훈;민상준;김태헌;유영수;강형원
    • 동의신경정신과학회지
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    • 제14권1호
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    • pp.155-160
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    • 2003
  • The Common Symptoms of insomnia are to be hard to sleep, not to get deep sleep, often wake up at night, be easy not to fall asleep again after waking up. In serious conditions, an insomniac can never get to sleep overnight. Herbal acupuncture therapy is especially used for patients who cannot take an oral medication. Another advantage of herbal acupuncture therapy is immediate effect of the herbal potency which is not destroyed during digestion. One patient who have taken western drugs for long time, was treated with Jahageo herbal acupuncture at BaekRo and AnMyen. effectively his insomnia was regulated. So We consider that Jahageo herbal acupuncture is useful in regulation insomnia.

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VORTEX 패널법을 이용한 비정상 3차원 날개의 피칭 운동에 관한 연구 (Computational Study of Unsteady Three Dimensional Wing in Pitching Motion Utilizing Linear Vortex Panel Method)

  • 정봉구;조태환
    • 한국항공우주학회지
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    • 제31권6호
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    • pp.1-7
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    • 2003
  • 본 연구에서는 3차원 대칭형 날개의 정상/비정상상대에서의 공기력 특성을 Vortex 패널법을 이용하여 수치적으로 연구했다. 이 프로그램은 날개 표면에 분포된 x, y 방향에 따라 선형적으로 변화는 와(Vortex)를 이용하는 프로그램을 기반으로 하여 3차원 날개 주위의 비압축성 포텐셜 흐름에 적용하였고 박리와 후류의 변형은 고려하지 않았다. NACA Airfoil 자료와 비교한 계산결과는 매우 만족스러운 일치를 보여주었다. 또한 갑작스러운 pitch-up운동과 일정한 각속도로 피칭운동을 하는 비정상 날개에 대해서도 본 방법을 적용하였다. 비정상 상태의 연구에서는 출발와류의 생성과 시간에 따른 위치를 고려함으로서 출발와류가 날개의 공기력 특성에 미치는 영향을 계산하였다. 본 방법은 피칭이나 플래핑, 회전익 해석등의 더 복잡한 경우에도 적용되어질 수 있다.

A 1.8 V 0.18-μm 1 GHz CMOS Fast-Lock Phase-Locked Loop using a Frequency-to-Digital Converter

  • Lee, Kwang-Hun;Jang, Young-Chan
    • Journal of information and communication convergence engineering
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    • 제10권2호
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    • pp.187-193
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    • 2012
  • A 1 GHz CMOS fast-lock phase-locked loop (PLL) is proposed to support the quick wake-up time of mobile consumer electronic devices. The proposed fast-lock PLL consists of a conventional charge-pump PLL, a frequency-to-digital converter (FDC) to measure the frequency of the input reference clock, and a digital-to-analog converter (DAC) to generate the initial control voltage of a voltage-controlled oscillator (VCO). The initial control voltage of the VCO is driven toward a reference voltage that is determined by the frequency of the input reference clock in the initial mode. For the speedy measurement of the frequency of the reference clock, an FDC with a parallel architecture is proposed, and its architecture is similar to that of a flash analog-to-digital converter. In addition, the frequency-to-voltage converter used in the FDC is designed simply by utilizing current integrators. The circuits for the proposed fast-lock scheme are disabled in the normal operation mode except in the initial mode to reduce the power consumption. The proposed PLL was fabricated by using a 0.18-${\mu}m$ 1-poly 6-metal complementary metal-oxide semiconductor (CMOS) process with a 1.8 V supply. This PLL multiplies the frequency of the reference clock by 10 and generates the four-phase clock. The simulation results show a reduction of up to 40% in the worstcase PLL lock time over the device operating conditions. The root-mean-square (rms) jitter of the proposed PLL was measured as 2.94 ps at 1 GHz. The area and power consumption of the implemented PLL are $400{\times}450{\mu}m^2$ and 6 mW, respectively.

The Experiment of Flow Induced Vibration in PWR RCCAs

  • Kim, Sang-Nyung;Cheol Shin
    • Journal of Mechanical Science and Technology
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    • 제15권3호
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    • pp.291-299
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    • 2001
  • Recently, severe wear on the shutdown rod cladding of Ulchin Nuclear Power Plant #1, #2 were observed by the Eddy Current Test(E.C.T.). In particular, the wear at the sixth card location was up to 75%. The test results indicated that the Flow Induced Vibration(F.I.V.) might be the cause of the fretting wear resulting from the contact between Rod Cluster Control Assemblies(RCCAs) and their spacing cards(guide plates) arranged in the guide tube. From reviewing RCCAs fretting wear repots and analyzing the general characteristics of F.I.V. mechanism in the reactor, geometric layout and flow conditions around the control rod, it is concluded that the turbulence excitation is the most probable vibration mechanism of RCCA. To identify the governing mechanism of RCCA vibration, an experiment was performed for a representative rod position in which the most serious fretting wear experienced among the six rod positions. The experimental rig was designed and set up to satisfy the governing nondimensional numbers which are Reynolds number and mass damping parameter. The vibration amplitude measurement by the non-contact laser displacement sensor showed good agreements in the frequency and the maximum wearing(vibration) location with Ulchin E.C.T. results and Framatome report, respectively. The sudden increase in the vibration amplitude was sensed around the 6th guide plate with mass flow rate variation. Comparing the similitude rod behaviour with the idealized response of a cylinder in flow induced vibration, it was found that he dominant mechanism of vibration was transferred from turbulence excitation to periodic shedding at the mass flow ate 90ι/min. Also the critical velocity of the vibration in RCCAs was determined and the vibration can be prevented by reducing the bypass flow rate below the critical velocity.

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에너지 수확 무선 센서 네트워크에서 에너지 효율 및 우선순위 기반의 MAC 프로토콜 (EEPB-MAC: Energy Efficient & Priority-Based MAC Protocol for Energy Harvesting Wireless Sensor Networks)

  • 김성철;전준헌
    • 한국정보통신학회논문지
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    • 제17권3호
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    • pp.755-761
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    • 2013
  • 무선 센서 네트워크에서 다중접근제어(Medium Access Control: MAC) 프로토콜은 센서 노드들이 필요할 때만 on 상태에 머물게 함으로 에너지를 효율적으로 사용하도록 하게한다. 본 논문에서는 에너지 수확 무선 센서 네트워크에서 우선순위에 기반을 둔 에너지 효율적인 MAC 프로토콜(EEPB-MAC)을 제안한다. 제안된 EEPB-MAC은 기존의 IEEE 802.15.4의 비콘 프레임에 우선순위 비트, 전송 노드 주소, NAV 값을 가지는 필드를 추가하여 이를 통하여 우선순위 데이터 전송을 지원한다. 데이터 전송을 원하는 전송자로부터 비콘 프레임을 수신한 수신 노드는 수신된 비콘 프레임의 우선순위 비트에 기반으로 데이터를 전송할 전송자를 선택한다. 데이터의 특성에 따라 우선순위 전송을 지원할 뿐 만 아니라, 수신 노드의 잔여 에너지 레벨에 따라 전송 주기를 조절하는 등 데이터 전송에 참여하는 노드에서의 에너지 소모를 줄인다. EEPB-MAC 프로토콜은 기존에 제안된 다른 프로토콜에 비해 우선순위가 높은 데이터에 대한 전송지연을 줄이며, 각 노드에서의 에너지 소모를 개선시켰다.

양허(陽虛) 불면증(不眠症)환자 치험 1례 (A Clinical Report of Insomnia due to deficiency of Yang)

  • 김수연;김은정;이동원;김경화
    • 동의신경정신과학회지
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    • 제15권1호
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    • pp.121-126
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    • 2004
  • 본 증례(證例)는 local 한의원에 2003. 12. 19.부터 2004. 1. 20.일 까지 래원(來院)한 환자의 주소증이 부면심계(不眠心悸) 불안(不安) 이경(易驚) 외한(畏寒) 조잡(?雜) 증상을 호소하는 환자에게 한약 처방과 침구치료(鍼灸治療)만으로도 좋은 결과를 보여준 사례이다. 특별한 검사를 하지 않고도 한의학적(韓醫學的)이론에 입각하여 사진(四診)을 하고 그것을 토대로 변증을 한 것이 치료에 효과를 보여준 사례이다. 이러한 증례가 한 예에 불과하므로 앞으로도 많은 임상 증례가 나오기를 기대한다.

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중풍(中風)에 활용(活用)된 자락요법(刺絡療法)에 대(對)한 문헌적(文獻的) 고찰(考察) (A Literatual Study on the effects of Bloodletting on C.V.A.)

  • 남창규;이진섭
    • 대한한방내과학회지
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    • 제15권2호
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    • pp.148-162
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    • 1994
  • A Literature study was done for identifying the effects of Bloodletting on C.V.A. The major results of the study were as follows. 1. The frequency of points of Bloodletting on C.V.A. were in order Twelve well point, Ship son, Gold SalivaJade Fluid, Paekoe, Chungchung, Sugu, Sosang, Taechu, Wijung, Kwanchung, etc. 2. The frequency of meridians of Bloodletting on C.V.A. were in order Extra-point, Tongmaek-kyong, Su-gworum-Shimpo-Kyong, Susoyang-Samcho-Kyong, Sutaeum-Pye-Kyong, Choktaeyang-Panggwang-Kyong. ete. 3. The frequency of the site of points of Bloodletting on C.V.A. were in order four extremities, face, neck and head, etc. 4. The effects of Bloodletting on C.V.A. is clear away heat and alleviate pain, therapy for waking up a patient from unconsciousness, dredge the meridian passage, expel wind-evil and promote blood circulation, emergency treatment for collapse, etc, 5. The effects of Bloodletting on the early stage of C.V.A. were wake up the patient from unconsciousness by clearing away the heat and The effects of Bloodletting on sequence of C.V.A. were dredge the meridian passage, 6. The frequency of points and meridians of Bloodletting on Hemiplegia were in order Twelve well point, Kyonjong, Extra-point, Chok soyang-Tam-Kyong, etc. 7. The frequency of points and meridians of Bloodletting on Aphasia were in order Gold Saliva Jade Fluid, Amun, Extra-point, Tongmaek-Kyong, etc. 8. The frequency of points and meridians of Bloodletting on Quadriplegia were in order Ship son, Twelve well point, Koktaek, Wijung, Extra-point, Chok soyang-Tam-Kyong, etc. 9, The frequency of points and meridians of Bloodletting on Vertigo were in order Four Gods Cleverness, Tuyu. Chanjuk, Paekoe, Taeyang, Extra-point, Yang-Kyong, etc. 10. The frequency of points and meridians of Bloodletting on Headache were in order Taeyang, Paekoe, Taechu, Extra-point, Tongmaek-Kyong, Yang-Kyong, etc. 11. The points and meridians of Bloodletting on Bells palsy were Chichang, Hyopko in Yangmyong-Kyong.

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