• Title/Summary/Keyword: control period

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Implementation of Temperature Control System of Boiler using Mobile Phone (모바일 전화기를 이용한 보일러 온도 조절 시스템 구현)

  • Han, Ki-Tae;Chung, Kyung-Yong;Kim, Sung-Ho
    • Proceedings of the Korea Contents Association Conference
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    • 2008.05a
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    • pp.611-613
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    • 2008
  • This paper describes the system that enables users to control the home electronic equipment using mobile phone. The home network industry is setting in network period that grow rapidly and get many interests. And, it is real condition that hailing of existed system is rising too. This paper developed system to make use of mobile phone regarding this and control boiler temperature in home to remote. This paper that serve this used skill of mobile programming, mobile Brew, RF radio communication, etc. for communication with server in an experiment. This paper presented another method that use RF radio communication and mobile device in home automation construction. The result of this paper will be expected to be able to contribute little in development of home network industry.

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A Design of Programmable Low Pass Filter to Reduce the ZCP Estimation Error at High Speed BLDC Sensorless Drive (BLDC 고속 센서리스 구동의 ZCP 추정 오차 저감을 위한 Programmable Low Pass Filter 설계)

  • Seo, Eunjeong;Lee, Kangseok;Lee, Wootaik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.1
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    • pp.35-41
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    • 2014
  • This paper presents a design method of programmable low pass filter(PLPF) which reduce an estimation error of a zero crossing point(ZCP) for a high speed brushless DC(BLDC) motor drive. BLDC motor sensorless drive is possible by estimation of ZCP. The ZCP estimated by detecting a change of back-EMF polarity has the estimation error because noises exist on the measured back-EMF. Therefore a calculated commutation timing using the ZCP is inaccurate. And the inexact commutation timing leads to ripples of 3-phase current and degradation of drive performance. This paper proposes the design method of the PLPF to overcome these problems. First, a speed calculated a inaccurate period of the ZCP is analyzed in the frequency domain. Then, the PLPF that has varying cut-off frequency according to change of the speed is designed on the frequency analysis result. The proposed method is verified by the experiment.

A Study on The Novel Structured 3-DOF Spherical Motor (새로운 3-자유도 구형 모터에 관한 연구)

  • Lee, Dong-Cheol;Kim, Dae-Kyong;Kwon, Byung-Il
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.8
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    • pp.1362-1370
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    • 2008
  • This paper describes the design and characteristic analysis of a novel 3-DOF(Degree of Freedom) spherical motor. For multi DOF actuating, several numbers of motors have been used. By the using of normal motors they connected each other in single joint, is necessary to a several type of complex power transmission devices. The 3-DOF spherical motor can drive roll, pitch, and yaw motion in only one unit and it is not necessary to use additional gears and links parts. Therefore the using of 3-DOF spherical motor can eliminate; combined effects of inertia, backlash, non-linear friction, and elastic deformation of gears. In this paper, we propose the novel structured 3-DOF spherical motor and derive its principles of operation. Firstly, we designed concept model of novel structured 3-DOF spherical motor. Next, we derive the control method by calculating the currents. Also, to have intuitive driving control, we express the rotor position in equivalent angle-axis system and determine the exciting period of currents from the calculation result of the currents. To verify the control method, we calculated the currents by the position of rotor. and then we analyzed the characteristics by 3D Finite Element Method when the calculated currents are excited.

Research on the actual condition of 'Under Floor Radiant Heating for Apartment Housing' (주거용건물의 바닥복사 난방방식에 대한 실태조사 연구)

  • Woo, Byung-Kwan;Lee, Sung;Kim, Sam-uel
    • KIEAE Journal
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    • v.7 no.5
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    • pp.81-86
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    • 2007
  • The research analyzes the arrangement of boiler and hot water header, the method of radiator pipe setting, hot water supply control, hourly heating situation of each room for underfloor radiant heating systems in Korea and suggests an alternative to improve to efficient heating method. One of the best options for install position of hot water distributor is under kitchen sink which is center point of all rooms, according to previous research of the energy saving strategies. When the radiator pipes are arranged to each individual room instead of bedrooms through livingroom and kitchen, it has energy saving effects. For rooms without occupancy according to a time period, hot water supply method should be intermittent heating rather than continuous heating. For this intermittent heating method, individual control of hot water supply is more practical, and it can lead to massive energy savings. The intermittent heating system has time-lag, so it is more effective in energy saving with mild and comfort condition if the spaces are preheated by automatic control equipment prior to required time.

Effect of Electrical Stimulation on the Denervated Muscle of the Albino Rat. Sprague-Dawley (전기자극이 흰쥐 탈신경 근육의 위축에 미치는 영향)

  • Lee, Jae-Hyoung;Lee, Kyung-Ro
    • The Journal of Korean Physical Therapy
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    • v.2 no.1
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    • pp.47-63
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    • 1990
  • The purpose of this study was to determined the effect of low-frequency electrical stimulation on the denervated gastrocnemius muscles of the albino rats, Sprague-Dawley. Fifteen Sprague-Dawley adult male albino rats were divided into non-treated (normal) group, denervated (control) group, denervated and electrical stimulated (experiments). The gastrocnemius muscles of the right leg were submaximally stimulated with 30 Hz electrical stimulation. After 4-week period, the animals were sacrificed, and muscle were removed, fixed by immersion, and processed for light and electron microscopy. The numbers of Ag-NOR increased significantly (p<0.001), but significant reductions of girth(p<0.01), wet muscle weight (p<0.001), high glycogen content fiber (p<0.01), and mitochondrial number (p<0.05) were found in denervated control group. In comparison with control group, significant increase of right leg girth (p<0.05), wet muscle weight (p<0.001), high glycogen content fiber (p<0.05), numbers of Ag-NOR(p<0.001), number of mitochondria (p<0.01), mitochondrial volume found in electrical stimulated experimental group. The results suggest that the electrical stimulation of the muscle partially prevented the denervated atrophy in the rat gastrocnemius muscles.

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The Chemical Components and Nutritional Evaluation of Aspergillus fumigatus Cells (Aspergillus fumigatus균체의 화학적 성분과 영양학적 평가)

  • 최종덕;조성환
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.1
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    • pp.41-47
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    • 1995
  • This experiments was designed to evaluated the chemical components and nutrition of Aspergillus fumigatus cells. This dried fungal mycellia was consist of crude protein 48.5%, crude lipid 2.9%, carbohydrate 44.7% and total ash 3.4%, respectively. The major fatty acid of total lipid were 27.9% of linoleic acid, 24.6% of oleic acid, 15.4% of palmitic acid and 10.6% of linolenic aicd. Amino acid analysis indicated that the protein was rich in aspartic acid, glutamic acid, leucine, lysine but poor in cystein, methionine, histidine. The fungal cake of Aspergillus fumigatus, when dried and specially processed, has been found to serve as a source of protein in place of soybean meal in the diet of experimental mice. Animal were fed a control diet first, and an incease in weight proved the formulation to be satisfactory. At the end of a 30-day period, the experimental mice showed increases in weight comparable to those of the control animals. The net protein efficiency ratio for the control diet was 3.42$\pm$0.15 and the fungal protein and succinylated fungal protein with DL-methionine they were 3.12$\pm$0.39 and 2.98$\pm$0.06 respectively. This supports the view that dried and succinylated fungal protein can be substituted as a protein source.

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Development of a Respiratory Nursing Program Using Recorder Playing for the Patients with Asthma and Measurement of Effectiveness (리코더를 활용한 천식환자의 호흡간호프로그램 개발 및 효과)

  • Jang, Hee-Jung
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.18 no.1
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    • pp.19-27
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    • 2011
  • Purpose: This study was conducted to develop a respiratory nursing program using recorder playing for patients with asthma and to determine the effects of the program. Method: Participants were 26 patients with asthma (experimental group: 13, control group: 13). The experimental group participated in the respiratory nursing program for six months from April, to October, 2007. Content included playing a recorder, group education about asthma, and educational messages including cellular phone messages. The control group received usual care during the six months. Results: In this research the respiratory nursing program using recorders was developed in 3 stages: initial stage, advanced stage, and wrap up stage. Compared to the control group, fatigue status in the experimental group improved significantly as well as level of forced expiratory volume in 1 second. However significant differences were found in sleep status, mood, or quality of life. Conclusions: These results suggest that this respiratory nursing program for symptom management of patients with asthma led to improvements in self care activity. Nursing interventions are needed to maintain and further enhance the quality of life of these patients and the interventions should be implemented over a transition period.

Multilevel performance-based procedure applied to moderate seismic zones in Europe

  • Catalan, Ariel;Foti, Dora
    • Earthquakes and Structures
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    • v.8 no.1
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    • pp.57-76
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    • 2015
  • The Performance-based Earthquake Engineering (PBEE) concept implies the definition of multiple target performance levels of damage which are expected to be achieved (or not exceeded), when the structure is subjected to earthquake ground motion of specified intensity. These levels are associates to different return period (RP) of earthquakes and structural behaviors quantified with adopted factors or indexes of control. In this work an 8-level PBEE study is carried out, finding different curves for control index or Engineering Demand Parameters (EDP) of levels that assess the structural behavior. The results and the curves for each index of control allow to deduce the structural behavior at an a priori unspecified RP. A general methodology is proposed that takes into account a possible optimization process in the PBEE field. Finally, an application to 8-level seismic performance assessment to structure in a Spanish seismic zone permits deducing that its behavior is deficient for high seismic levels (RP > 475 years). The application of the methodology to a low-to-moderate seismic zone case proves to be a good tool of structural seismic design, applying a more sophisticated although simple PBEE formulation.

Production Practices for North American Ginseng: Challenges and Opportunities

  • Proctor John T.A.
    • Proceedings of the Ginseng society Conference
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    • 2002.10a
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    • pp.212-226
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    • 2002
  • North American ginseng production may have been maximized in the traditional growing areas in the last decade and further increases may be in woods grown root, for niche markets. The marketplace demands high quality roots. Most problems leading to low quality roots start with the grower and can be avoided. These include poor site selection, inadequate soil drainage, untimely and poorly applied pesticides, and neglect of good sanitary practices. Selection of low lying sites increased the plant damage from frost in Ontario in May 2002. Seeding is still the major method of propagation of ginseng in spite of some success in culturing different parts of the plant. Opportunities exist for shortening the stratification period of North American ginseng seed to allow spring planting. This may reduce disease incidence. Since only one-third of ginseng seed sown ultimately produces plants harvested after 3 years any approach that reduces disease incidence and improves seed germination, seedling emergence and crop stand must be pursued. Disease is the major problem in ginseng cutivation from seed stratification, soil preparation prior to planting, right through to drying of the roots. Replant disease remains as an unresolved problem and needs full characterization and new approaches for control. Much progress has been made in research and related extension activities in disease control although challenges will arise such as with Quintozene and its replacement with Quadris for control of diseases caused by Rhizoctonia. Decreased labor populations and increased associated costs for ginseng production are causing rapid mechanization in every aspect of the ginseng industry. Engineers, machinery dealers, and fabricators, and growers are being challenged to increase efficiency by mechanization.

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Decision Tree Model for Predicting Hospice Palliative Care Use in Terminal Cancer Patients

  • Lee, Hee-Ja;Na, Im-Il;Kang, Kyung-Ah
    • Journal of Hospice and Palliative Care
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    • v.24 no.3
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    • pp.184-193
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    • 2021
  • Purpose: This study attempted to develop clinical guidelines to help patients use hospice and palliative care (HPC) at an appropriate time after writing physician orders for life-sustaining treatment (POLST) by identifying the characteristics of HPC use of patients with terminal cancer. Methods: This retrospective study was conducted to understand the characteristics of HPC use of patients with terminal cancer through decision tree analysis. The participants were 394 terminal cancer patients who were hospitalized at a cancer-specialized hospital in Seoul, South Korea and wrote POLST from January 1, 2019 to March 31, 2021. Results: The predictive model for the characteristics of HPC use showed three main nodes (living together, pain control, and period to death after writing POLST). The decision tree analysis of HPC use by terminal cancer patients showed that the most likely group to use HPC use was terminal cancer patients who had a cohabitant, received pain control, and died 2 months or more after writing a POLST. The probability of HPC usage rate in this group was 87.5%. The next most likely group to use HPC had a cohabitant and received pain control; 64.8% of this group used HPC. Finally, 55.1% of participants who had a cohabitant used HPC, which was a significantly higher proportion than that of participants who did not have a cohabitant (1.7%). Conclusion: This study provides meaningful clinical evidence to help make decisions on HPC use more easily at an appropriate time.