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Tele-metering

  • Hearte, L.O.
    • 전기의세계
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    • v.2
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    • pp.6-14
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    • 1949
  • Telemetering may be described as the art of metering at a considerable distance those quantities which are ordinarily encountered in industry, and in the generation of electric power. It is in the production of electric power that telemetering is particularly important, for it permits the system operator, or load dispatcher, to have before him at all times a continuous graphic record of the power output of each individual generating station together with an automatically made continuous graphic record of the total system output. There desired individual graphic records may be obtained showing power flow in or out, on important tie lines, etc. Such arrangements have the very great advantage that loads may be assigned to each generating station so that the best over-all system economy may be obtained and the system operator at all times may see with his own eyes that loads scheduled are actually held at the various stations. Moreover, with such equipment, in the event of system or station trouble the load dispatcher can see exactly what station, or stations, are affected and to what extent, without having to get in touch with anyone by telephone. Decisions can, therefore, be quickly reached for rescheduling the load. One of the most accurate and reliable telemetering systems is based on the use of potentiometric circuits, the fundamentals of which are discussed below. A member of such telemetering systems have been installed for the Boston Edicon Co., Boston, Massachusetts, the Consolidated Edison Co. of New York City. The Public Service Gas & Electric Co. of Newark, new Jersey. The Philadelphia Electric Co. for Philadelphia, Pennsylvania, and the Pennsylvania Railroad Co. for their electrified zone between New York and Washington a distance of over 200 miles. The scale of the totalizing recorder for the New York area is 3,000,00 KW. That of the totalizing recorder for the Philadelphia area is 2,000,000 KW. The initial installation using this type of equipment described was placed in service for the Philadelphia Electric Co. in 1923. All of the original recording instruments are still in service, later instruments have been added to take care of additions to the power system and naturally these later recorders have incorporated in those refinements in design made since the earlier ones were manufactured. Many other installations of similar equipment have been made in the United States in various locations such as at St. Louis, on the West Coast, at Baltimore and in Washington, D.C. While the use of these basic potentiometric circuits involves the use of continuous metallic circuits of good insulation resistance and free of grounds, nevertheless, intermediate transmission links, involving and impulse method suitable for use on telephone Morse carrier channels is available. This same method may be employed on power line carrier systems and is also suitable for use on beam type microwave transmission. Many impulse type units are also used as a link in these potantiometric methods. For the sake of brevity a description is given only of these basic potentiometric circuits. If there is sufficient interest in Korea, a further paper can be given covering those impulse circuits also.

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Dispersion in the Unsteady Separated Flow Past Complex Geometries (복합지형상에서 비정상 박리흐름에 의한 확산)

  • Ryu, Chan-Su
    • Journal of the Korean earth science society
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    • v.22 no.6
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    • pp.512-527
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    • 2001
  • Separated flows passed complex geometries are modeled by discrete vortex techniques. The flows are assumed to be rotational and inviscid, and a new techlnique is described to determine the stream functions for linear shear profiles. The geometries considered are the snow cornice and the backward-facing step, whose edges allow for the separation of the flow and reattachment downstream of the recirculation regions. A point vortex has been added to the flows in order to constrain the separation points to be located at the edges, while the conformal mappings have been modified in order to smooth the sharp edges and to let the separation points free to oscillate around the points of maximum curvature. Unsteadiness is imposed to the flow by perturbing the vortex location, either by displacing the vortex from the equilibrium, or by imposing a random perturbation with zero mean to the vortex in equilibrium. The trajectories of passive scalars continuously released upwind of the separation point and trapped by the recirculating bubble are numerically integrated, and concentration time series are calculated at fixed locations downwind of the reattachment points. This model proves to be capable of reproducing the trapping and intermittent release of scalars, in agreement with the simulation of the flow passed a snow cornice performed by a discrete multi-vortex model, as well as with direct numerical simulations of the flow passed a backward-facing step. The results of simulation indicate that for flows undergoing separation and reattachment the unsteadiness of the recirculating bubble is the main mechanism responsible for the intense large-scale concentration fluctuations downstream.

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The Comparison of Clinical Variables in Two Classifications: GOLD 2017 Combined Assessment and Spirometric Stage of Chronic Obstructive Pulmonary Disease

  • Candemir, Ipek;Ergun, Pinar;Kaymaz, Dicle;Tasdemir, Filiz;Egesel, Nurcan
    • Tuberculosis and Respiratory Diseases
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    • v.81 no.4
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    • pp.281-288
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    • 2018
  • Background: There are limited number of studies that investigate clinical variables instead of chronic obstructive lung disease (COPD) management according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 classification. The aim of the study was to investigate whether there was a difference between GOLD 2017 classification and spirometric stage in clinical variables in patients with COPD. The data of 427 male patients with stable COPD were investigated retrospectively. Methods: Patients were allocated into combined assessment of GOLD 2017 and spirometric stage. Age, amount of smoking, pulmonary function, modified Medical Research Council (mMRC), incremental shuttle walk test (ISWT), Hospital Anxiety-Depression Scale (HADS), St. George's Respiratory Questionnaire (SGRQ), body mass index (BMI), and fat free mass index (FFMI) were recorded. Results: Seventy-three (17%) patients were in group A, 103 (24%) constituted group B, 38 (9%) were included in group C, and 213 (50%) comprised group D according to the combined assessment of GOLD 2017. Twenty-three patients (5%) were in stage 1, 95 (22%) were in stage 2, 149 (35%) were in stage 3, and 160 (38%) were in stage 4 according to spirometric stage. According to GOLD 2017, age, amount of smoking, mMRC, BMI, FFMI, SGRQ, HADS, forced vital capacity, forced expiratory volume in 1 second ($FEV_1$), and ISWT were significantly different between groups. Ages, amount of smoking, FFMI, BMI, HADS of group A were different from B and D. Smiliar values of $FEV_1$ were found in A-C and B-D. A and C had smiliar ISWT. According to spirometric stage, BMI, FFMI of stage 4 were statistically different. mMRC, ISWT, and SGRQ of stages 3 and 4 were different from other stages, amongst themselves. $FEV_1$ was correlated with mMRC, SGRQ, anxiety scores, BMI, FFMI, and ISWT. Conclusion: This study showed that the GOLD ABCD classification might not represent the severity of COPD sufficiently well in terms of lung function or exercise capacity. The combination of both spirometric stage and combined assessment of GOLD 2017 is important, especially for estimating clinical variables.

Conical Diffuser Design and Hydraulic Performance Characteristics in Bioreactor Using Empirical and Numerical Methods (원뿔형 산기관 설계와 생물반응조에서 수력학적 운전특성에 관한 실험 및 해석)

  • Lee, Seung-Jin;Ko, Kyeong-Han;Ko, Myeong-Han;Yang, Jae-Kyeong;Kim, Yong-Guk
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.8
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    • pp.633-643
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    • 2015
  • In this study, we develop a highly efficient conical-air diffuser that generates fine bubble. By inserting a sufficient number of aerotropic microorganisms with dissolved oxygen from an air diffuser and minimizing the air-channel blockages within the air diffuser, we expect to improve the efficiency and durability of the decomposition process for organic waste. To upgrade the conventional air diffuser, we perform experiments and numerical analysis to develop a conical-type that generates fine bubble, and which is free from nozzle blockage. We complement the air-diffuser design by numerically analyzing the internal air-flow pattern within the diffuser. Then, by applying the diffuser to a mockup bioreactor, we experimentally and numerically study the bubble behavior observed in the diffuser and the 2-phase fluid flow in the bioreactor. The results obtained include statistics of the cord length and increased velocity, and we investigate the mechanisms of the fluid-flow characteristics including bubble clouds. Throughout the study, we systemize the design procedures for the design of efficient air diffusers, and we visualize the fluid-flow patterns caused by bubble generation within the mockup bioreactor. These results will provide a meaningful basis for further study as well as the detection of oxygen transfer and fluid-flow characteristics in real-scale bio-reactors using sets of air diffusers.

Analysis of Spectator Mobilizing Power for 2000's Korea Movies Based on Construction of Network (네트워크 기반 2000년대 한국영화의 관객 동원력 분석)

  • Kim, Hak-Yong
    • The Journal of the Korea Contents Association
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    • v.11 no.1
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    • pp.429-437
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    • 2011
  • Movie network as a social network shows power-law distribution that is one of distinct properties in scale-free network. We constructed movie network from 799 Korea movies that screened from 2000 to 2009 and analyzed structural properties of the network. The 799 movies was classified three groups as a spectator mobilizing power. One million spectators mobilizing power movie was denoted the first class. The best 10 movie directors who produced at least three movies for ten years and had 70% the first class movie of them were selected. We also preferred the best 20 movie actors who played at least five movies for ten years and had 70% the first class movie of them. We re-constructed core movie network that composed the best 10 directors, the best 20 movie stars, and 157 movies that were produced by the directors or were played by the movie stars. We predict a possible combination of the director and movie actor as a category of the movie that has highly spectator mobilizing power. Here, we provide insight and method for producing high spectators mobilizing power movies

A Study on Selection Attributes and Information Sources of Optical Shop (안경원 선택속성과 정보원천에 관한 연구)

  • Cha, Jung-Won
    • Journal of Korean Ophthalmic Optics Society
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    • v.21 no.3
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    • pp.173-179
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    • 2016
  • Purpose: This study is to help assist in the management of optical shops by using the importance sequence of optical shop selection attributes, which is related to the consumer's selection method of consumer, and by using the importance sequence of optical shop information sources which is related to a route for optical shop selection. Methods: Customer surveys were conducted from March 10 to March 31, 2015 targeting customers who have visited an optical shop in Seoul and Northern Gyeonggi-do regions. The analys method was descriptive statistics and data were analyzed by utilizing SPSS v.10.0 statistical package program. Results: The highest ranking five attributes among the importance of optical shop selection are "friendliness and politeness of staff", "cleanliness of an optical shop", "quick resolution of customer's complaints by staff", "eyes examination and glasses dispensing skill of staff", "customer's complaints and claims handling". The lowest ranking five attributes among the importance of optical shop selection are "provide free gifts", "scale or size of an optical shop", "opening time and closing time", "convenient parking facilities", "favorable countenance of staff". The two highestr ranking criteria among the importance of optical shop information sources are "previous utilization experience", "recommendation by a relative, a friend and a family etc". The two lowest ranking criteria among the importance of optical shop information sources are "advertisement" and "spatial exterior view of optical shop". Conclusions: It is shown that the important thing in management of an optical shop is an inner caliber like ability of ophthalmic optician, interaction with customers, and previous utilization experience rather than external factors like advertisement, exterior view, and bonus gift.

The use of SMA wire dampers to enhance the seismic performance of two historical Islamic minarets

  • El-Attar, Adel;Saleh, Ahmed;El-Habbal, Islam;Zaghw, Abdel Hamid;Osman, Ashraf
    • Smart Structures and Systems
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    • v.4 no.2
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    • pp.221-232
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    • 2008
  • This paper represents the final results of a research program sponsored by the European Commission through project WIND-CHIME ($\underline{W}$ide Range Non-$\underline{IN}$trusive $\underline{D}$evices toward $\underline{C}$onservation of $\underline{HI}$storical Monuments in the $\underline{ME}$diterranean Area), in which the possibility of using advanced seismic protection technologies to preserve historical monuments in the Mediterranean area is investigated. In the current research, the dynamic characteristics of two outstanding Mamluk-Style minarets, which similar minarets were reported to experience extensive damage during Dahshur 1992 earthquake, are investigated. The first minaret is the Qusun minaret (1337 A.D, 736 Hijri Date (H.D)) located in El-Suyuti cemetery on the southern side of the Salah El-Din citadel. The minaret is currently separated from the surrounding building and is directly resting on the ground (no vaults underneath). The total height of the minaret is 40.28 meters with a base rectangular shaft of about 5.42 ${\times}$ 5.20 m. The second minaret is the southern minaret of Al-Sultaniya (1340 A.D, 739 H.D). It is located about 30.0 meters from Qusun minaret, and it is now standing alone but it seems that it used to be attached to a huge unidentified structure. The style of the minaret and its size attribute it to the first half of the fourteenth century. The minaret total height is 36.69 meters and has a 4.48 ${\times}$ 4.48 m rectangular base. Field investigations were conducted to obtain: (a) geometrical description of the minarets, (b) material properties of the minarets' stones, and (c) soil conditions at the minarets' location. Ambient vibration tests were performed to determine the modal parameters of the minarets such as natural frequencies and mode shapes. A $1/16^{th}$ scale model of Qusun minaret was constructed at Cairo University Concrete Research Laboratory and tested under free vibration with and without SMA wire dampers. The contribution of SMA wire dampers to the structural damping coefficient was evaluated under different vertical loads and vibration amplitudes. Experimental results were used along with the field investigation data to develop a realistic 3-D finite element model that can be used for seismic risk evaluation of the minarets. Examining the updated finite element models under different seismic excitations indicated the vulnerability of such structures to earthquakes with medium to high a/v ratio. The use of SMA wire dampers was found feasible for reducing the seismic risk for this type of structures.

An Exploratory Study of Japanese Fathers' Knowledge of and Attitudes towards HPV and HPV Vaccination: Does Marital Status Matter?

  • Hanley, Sharon Janet Bruce;Yoshioka, Eiji;Ito, Yoshiya;Konno, Ryo;Sasaki, Yuri;Kishi, Reiko;Sakuragi, Noriaki
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.4
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    • pp.1837-1843
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    • 2014
  • Background: No studies on male attitudes towards HPV and HPV vaccination have been conducted in Japan, and little is known globally whether attitudes of single fathers differ to those living with a female partner. This exploratory study assessed whether Japanese fathers were likely to have their daughter vaccinated against HPV in a publically funded program and whether any differences existed regarding attitudes and knowledge about HPV according to marital status. Materials and Methods: Subjects were 27 fathers (16 single; 11 married) who took part in a study on HPV vaccine acceptability aimed at primary caregivers of girls aged 11-14 yrs in three Japanese cities between July and December 2010. Results: Knowledge about HPV was extremely poor (mean score out of 13 being $2.74{\pm}3.22$) with only one (3.7%) participant believing he had been infected with HPV and most (81.4%) believing they had no or low future risk. No difference existed regarding knowledge or awareness of HPV according to marital status. Concerning perceived risk for daughters, single fathers were significantly more likely to believe their daughter was at risk for both HPV (87.5% versus 36.4%; p=0.01) and cervical cancer (75.0% versus 27.3%; p=0.02). Acceptability of free HPV vaccination was high at 92% with no difference according to marital status, however single fathers were significantly more likely (p=0.01) to pay when vaccination came at a cost. Concerns specific to single fathers included explaining the sexual nature of HPV and taking a daughter to a gynecologist to be vaccinated. Conclusions: Knowledge about HPV among Japanese fathers is poor, but HPV vaccine acceptability is high and does not differ by marital status. Providing sexual health education in schools that addresses lack of knowledge about HPV as well as information preferences expressed by single fathers, may not only increase HPV vaccine acceptance, but also actively involve men in cervical cancer prevention strategies. However, further large-scale quantitative studies are needed.

Model Simulation for Assessment of Image Acquisition Errors Affecting Electron Tomography (영상 자료 획득시의 오류가 전자토모그래피 결과에 미치는 영향 고찰-모델 시뮬레이션을 중심으로)

  • Jou, Hyeong-Tae ;Lee, Su-Jeong;Kim, Youn-Joong;Suk, Bong-Chool
    • Applied Microscopy
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    • v.38 no.1
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    • pp.51-61
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    • 2008
  • This simulation study examined the effect of data acquisition error including the data type of TEM image, and incident beam intensity of the tilt series on 3D tomograms. Simulation was performed with the 3D head phantom model of Kak and Slaney, and the slightly modified 3D head phantom model with enhanced difference in absorption coefficients. Reconstructed tomogram for the original head phantom model using 8-bit gray-scale image was distorted with extremely high level of noise, while an acceptable result was obtained for the modified model. The results for the original model using wrong formulation for the transmitted beam intensity was proved to be incorrect. The high level of noise along the z direction was found in case of the modified model. On the other hand, the wrong value of incident beam intensity in both models gave distorted results. In order to reconstruct an artifacts-free 3D structure from the projections with invisible features in electron tomography, the 16-bit projection images should be used with the correct incident beam intensity which is applied to Beer's law.

Dynamic Frictional Behavior of Artificial Rough Rock Joints under Dynamic Loading (진동하중 하에서 거친 암석 절리면의 동력 마찰거동)

  • Jeon Seok-Won;Park Byung-Ki
    • Tunnel and Underground Space
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    • v.16 no.2 s.61
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    • pp.166-178
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    • 2006
  • Recently, the frequency of occurring dynamic events such as earthquakes, explosives blasting and other types of vibration has been increasing. Besides, the chances of exposure for rock discontinuities to free faces get higher as the scale of rock mass structures become larger. For that reason, the frictional behavior of rock joints under dynamic conditions needs to be investigated. In this study, artificially fractured rock joint specimens were prepared in order to examine the dynamic frictional behavior of rough rock joint. Roughness of each specimen was characterized by measuring surface topography using a laser profilometer and a series of shaking table tests was carried out. For mated joints, the static friction angle back-calculated ken the yield acceleration was $2.7^{\circ}$ lower than the tilt angle on average. The averaged dynamic friction angle for unmated joints was $1.8^{\circ}$ lower than the tilt angle. Displacement patterns of sliding block were classified into 4 types and proved to be related to the first order asperity of rock joint. The tilt angle and the static friction angle for mated joints seem to be correlated to micro average inclination angle which represents the second order asperity. The tilt angle and the dynamic friction angle for unmated Joints, however, have no correlation with roughness parameters. Friction angles obtained by shaking table test were lower than those by direct shear test.