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Pharmacognostical Evaluation of Trachyspermum roxburghianum (DC) Craib Fruits

  • Verma, Nitin;Khosa, R.L.
    • Natural Product Sciences
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    • v.17 no.1
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    • pp.45-50
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    • 2011
  • Sophisticated modern research tools for evaluation of medicinal plants are available but microscopic methods are one of the simplest and cheapest methods to establish the identity of the source materials. Pharmacognostical investigation of the dried, powdered and anatomical sections of the fruits of Trachyspermum roxburghianum (DC) Craib was carried out to determine its macro and microscopical characteristics along with its physical constants. Externally, the fruits, yellowish or greenish brown in colour are elongated, elliptical, slightly curved, prominently ridged and longitudinal. As seen in transectional views of the fruits from Trachyspermum roxburghianum, the mericarp has concave sides called commissural surfaces and a convex outer side called the dorsal surface. The mericarp has three primary ridges alternating with two secondary ridges on the dorsal side. On the commissural side, there are two primary ridges which are lateral in position and two secondary ridges in the commissural side. The seed is attached to the pericarp by a short stalk called a raphe. Circular, four-lobed calcium oxalate crystals are fairly abundant in the endosperm. Phytochemical studies revealed the presence of phenolic compounds, triterpenoids, proteins and sugars. The pharmacognostical profile of the fruits will assist in standardization for quality, purity and sample identification.

A Study on the Clinical Use of 7-zone-diagnostic System(1) Centering around VEGA-DFM 722 and ABR-2000- (7구역진단기의 임상응용에 대한 고찰(1) -VEGA-DFM 722 및 ABR-2000 중심으로-)

  • Song, Beom-Yong
    • Journal of Acupuncture Research
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    • v.23 no.3
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    • pp.231-239
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    • 2006
  • Functional medicine is a system which utilizes certain investigative and treatment methods that are primarily oriented toward the recognition of functional disorder. Functional disorders take place on an energetic plane. This plane is not capturable using our regular investigatory techniques, such as X -ray. ultrasound, computer tomography and laboratory analyses. The 7-zone-diagnostic system(VEGA-DFM 722 and ABR-2000, etc) is a diagnostic device Which applies pulse signals to predetermined bodily locations. Applying alternating positive and negative stress to tissues with positive and negative pulses first manifests itself as negative and positive wave forms. The skin has many functions as an organ. It is the organism's interlace with the outsider world. Hence, the manner in which the skin reacts to external stimuli reflects the current state of the organism(as meridian systems). This system make a diagnosis of functional disorder or some typical organic diseases include stress of the mind or the body, and the energetic situation, reserves. We are known a disorder or disease throw the result chart. This result chart contain disorder flow wave forms and some valuable diagnostic hints (letters ; S, OM, RA, etc). In spite of this 7-zone-diagnostic system that is applied plentifully in the clinical application, there is not a statistics which is suitable. Therefor we must carry out many various research in the future.

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Power Frequency Magnetic Field Reduction Method for Residents in the Vicinity of Overhead Transmission Lines Using Passive Loop

  • Lee, Byeong-Yoon;Myung, Sung-Ho;Cho, Yeun-Gyu;Lee, Dong-Il;Lim, Yun-Seog;Lee, Sang-Yun
    • Journal of Electrical Engineering and Technology
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    • v.6 no.6
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    • pp.829-835
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    • 2011
  • A power frequency magnetic field reduction method using passive loop is presented. This method can be used to reduce magnetic fields generated within the restricted area near transmission lines by alternating current overhead transmission lines. A reduction algorithm is described and related equations for magnetic field reduction are explained. The proposed power frequency magnetic field reduction method is applied to a scaled-down transmission line model. The lateral distribution of reduction ratio between magnetic fields before and after passive loop installation is calculated to evaluate magnetic field reduction effects. Calculated results show that the passive loop can be used to cost-effectively reduce power frequency magnetic fields in the vicinity of transmission lines generated by overhead transmission lines, compared with other reduction methods, such as active loop, increase in transmission line height, and power transmission using underground cables.

AC Arc Detection Method using Mixed Filter and Frequency Analysis (혼합필터와 주파수분석기법을 이용한 교류 아크 검출 기법)

  • Jang, Dong-Uk;Park, Seong-Hee;Lee, Kang-Won
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.66 no.4
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    • pp.200-205
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    • 2017
  • In this paper, we propose a technique to determine the normal and arc of an alternating current using a mixed filter composed of an average filter and a band-pass filter and a frequency analysis. The proposed method uses the moving average filter of the FIR filter structure for noise removal and the band-pass filter of the IIR filter structure for detecting only specific frequency components after normalizing the measured current signal based on the maximum value. After performing Fast Fourier Transform (FFT) using the band-pass filtered signal, the total energy is calculated using the magnitude component of the frequency, and the arc is detected using the magnitude of the calculated energy. In order to show the validity of the proposed method, we experimented with various data and found that arc and steady state can be easily discriminated by calculating spectral energy. Therefore, it is considered that the proposed method can be applied to arc diagnosis of low voltage electric wire.

Operating Characteristics of Arc-induction Type DC Circuit Breaker (아크유도형 DC 차단기의 동작 특성)

  • Park, Sang-Yong;Choi, Hyo-Sang
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.7
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    • pp.981-986
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    • 2018
  • AC(alternating current) CB(circuit breaker) at the fault occurred in the existing AC distribution system is limiting the fault current through zero cross-point. However, DC(direct current) CB does not have zero cross-point. Therefore, arc occurred by on-off operation of DC CB is very huge. Nowadays, many research team are studying the way to decrease breaking time, which is one of the essential conditions in DC CB. We suggested novel arc-induction type DC CB in this paper. The proposed arc-induction type DC CB is composed of the mechanical Arc ring and DC CB. We confirmed the operation of arc-induction type DC CB through the HFSS(High Frequency Structure Simulator) 3D simulation program and performed the experiment for operation characteristics. Results showed that arcing time of the arc-induction type DC CB by using induction ring was faster than existing mechanical DC CB. On the transient system, we confirmed stable operation characteristics of the arc-induction type DC CB through the simulation and experimental results. We expect that the proposed arc-induction type DC CB technology is will go to stay ahead of the existing DC CB technology.

An Empirical Study on Malfunction of the Earth Leakage Circuit Breaker (전기적 노이즈에 의한 누전차단기의 오동작에 관한 실험적 연구)

  • Kim, Tae-Man;Kwon, Yong-Jun;Kee, Do-Hyung
    • Journal of the Korean Society of Safety
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    • v.17 no.1
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    • pp.45-53
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    • 2002
  • The purpose of this study was to investigate effect of electrical noise on malfunction of the earth leakage circuit breaker. A three-way experiment for studying its malfunction was conducted, in which electrical products such as radio, alternating current are welder and cellular phone, distance from the earth leakage breaker to electrical products, and whether or not the earth leakage breaker is contained is contained in the steel box were employed as experimental variables. Eleven earth leakage breakers frequently used in real situations were tested in each experimental treatment. The electrical products were used for generating electrical noise that is known to be able to cause malfunction of the earth leakage breaker. The results showed that except a case for one of the 11 earth leakage breakers when the radio made by M company was located 30 cm ahead of the breaker, malfunction did not occur in any other experimental treatment. Consequently, it is suggested that the breaker should be normally used for preventing electricity-related accidents without fear of its malfunction in industrial sites.

A Study on the concept of makwon in onbyeonghak(溫病學) and its practical application (온병학(溫病學)의 막원(膜原) 개념과 그 실제적 활용에 대한 고찰)

  • Kim, Sanghyun
    • Journal of Korean Medical classics
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    • v.30 no.4
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    • pp.83-93
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    • 2017
  • Objective : Doctors' discussions on Makwon's warm-disease are studied in an effort to contemplate a way to use the outcome in practice. Method : Doctors' discussions on Makwon as found in researches and texts are categorized into physical and pathologica, and their symptoms and treatments are analyzed. Result & Conclusion : Many doctors of warm disease explained that, in terms of the physical aspect, Makwon is closely related to stomach. Some doctors also mentioned its relationship with triple engizers, defense and nutrient qi, and spleen. In terms of pathology, most of the doctors considered Makwon to be a hiding place of foul turbidity pathogen, and explained that a treatment has to be applied before the disease pattern worsens. Diverse syndroms of Makwonwere introduced. Their discussions mainly revolved around warm and epidemic or category of dampness-heat diseases. Alternating chills and fever was also mentioned often, and generalized pain, nausea, tongue of thick and slimy fur symptoms are shown. Ouguk's Dalwonneum is used as the basic treatment. The most effective prevention method of the incubation of pathogen are the symptoms that allows the analysis of the mechanism of disease. Therefore, a good utilization method of resolve turbidity with aroma or spices may contribute to the prevention of Makwon-disease in terms of cultural aspect.

High Efficient Energy Recovery Circuit for AC Plasma Display Panel (AC Plasma Display Panel 구동 장치의 고효율 전력 회수 회로에 관한 연구)

  • 윤원식;강필순;김철우
    • The Transactions of the Korean Institute of Power Electronics
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    • v.6 no.6
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    • pp.481-488
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    • 2001
  • The sustaining driver for color AC Plasma Display Panel should provide alternating high voltage pulses and recover the energy discharged from the intrinsic capacitance between the scanning and sustaining electrodes inside the panel In this paper a novel efficient energy recovery circuit employing boost-up function is proposed to achieve a faster rise-time and in order to obtain a stable sustain voltage The principle of operation. features simulated results and experiment results are illustrated and verified on a 7.5-inch-panel with 200[kHz]switch frequency.

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Evaluation of AC Resistance in Litz Wire Planar Spiral Coils for Wireless Power Transfer

  • Wang, Xiaona;Sun, Pan;Deng, Qijun;Wang, Wengbin
    • Journal of Power Electronics
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    • v.18 no.4
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    • pp.1268-1277
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    • 2018
  • A relatively high operating frequency is required for efficient wireless power transfer (WPT). However, the alternating current (AC) resistance of coils increases sharply with operating frequency, which possibly degrades overall efficiency. Hence, the evaluation of coil AC resistance is critical in selecting operating frequency to achieve good efficiency. For a Litz wire coil, AC resistance is attributed to the magnetic field, which leads to the skin effect, the proximity effect, and the corresponding conductive resistance and inductive resistance in the coil. A numerical calculation method based on the Biot-Savart law is proposed to calculate magnetic field strength over strands in Litz wire planar spiral coils to evaluate their AC resistance. An optimized frequency can be found to achieve the maximum efficiency of a WPT system based on the predicted resistance. Sample coils are manufactured to verify the resistance analysis method. A prototype WPT system is set up to conduct the experiments. The experiments show that the proposed method can accurately predict the AC resistance of Litz wire planar spiral coils and the optimized operating frequency for maximum efficiency.

The Effects of a Launching Nose on Main Girder Erected by Incremental Launching Method (압출공법에 의한 가설시 추진코가 주형에 미치는 영향)

  • Oh, Kwi Hwan;Kim, Chul Young;Park, Young Suk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.4
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    • pp.1-10
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    • 1992
  • Since the structural system of a prestressed concrete bridge erected by Incremental Launching Method is varying continuosly during construction, the main girder bears alternating stress resultants different from those under a service load condition. The magnitude of these stress resultants depends on span lengths, nose length and stiffness ratios between girder and nose. A parametric study is performed for various span lengths, nose lengths and stiffness ratios. In order to analyze structural systems varying at every launching step two programs are developed; a pre-processor which automatically produces a data file for each stage and a main-processor which can summarize the results of all stages. From the results, the relationships between optimum nose length and stiffness ratio are proposed for various span lengths.

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