• Title/Summary/Keyword: low gain

Search Result 2,480, Processing Time 0.051 seconds

A study on old trees as they relate to the organization of space in Pusan -Attaching importance to the growth environment and arrangement form in space- (부산시 노거수의 공간구성에 관한 연구 -생육환경 및 배치형태를 중심으로-)

  • 김승환;김순희
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.24 no.2
    • /
    • pp.86-98
    • /
    • 1996
  • This study is intended to revaluate old tree, five of the shot of the Natural Monument and 66 shot trees under protection in the city at present. The study covers distribution, management of usage, investigation and research into various matters relating to the situation of old trees in Pusan. Because 60% of the old trees selected for protection is on private land, citizens have difficulty gaining access to them. Also space for growth is impinged on by various urban facilities. Some trees have problems of growth because the land is covered with cement and asphalt. As regards space for old trees, many places have been destroyed due to the lack of protection fences and the failure to establish a guidance board. Only 40% of the space has been set aside for rest. In these places the establishment of rest areas, benches and handy chairs is needed. And there are 20 holy places where people observe religious ceremonies. As for space security necessary for old trees according to trunk width, the minimum trunk width and availale area needed are more than 1:1.5, but less than 30% have the necessary space. The growth of many old trees is threatended because of the small apace for growth. The prescription of the boundary space is divided between inside and outside. This indicates the domain nature and space rank of the old tree. It can be classified into five forms for research purposes. The elements for prescription of critical space outside are connected with the security of space, and the elements relating to inside space portray the conditions for sensitive growth according to the institution and the ground conditions. The open and closed nature of old tree space has some connection with the relationship between usage and the intimacy of the user. Most of the spaces for old trees can't be used or are difficult to gain access to, so it is necessary to secure enough space for them. The 18 places, despite having easy access, are near farmland, hills or forest. So the intimacy factor is low, and the security of space of the old trees is not generally sufficient. Henceforth, it will be necessary to have security of area for old trees as well as maintenance control to protect them. Also the space should be used as a communal and recreation are in the city. It is the time to construct a landscaped area which people can easily approach, a place with a secure entrance where they can play, rest and converse.

  • PDF

Design of Dual Band Antenna for UWB / WAS for Wireless Local Area Communication (무선 근거리 통신을 위한 UWB/WAS용 이중대역 안테나 설계)

  • Kim, Gyeong-rok;Oh, Mal-geun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2018.10a
    • /
    • pp.522-525
    • /
    • 2018
  • In this paper, we design a UWB / WAS microstrip antenna for wireless local high - speed communication. The substrate of the proposed antenna is FR-4 (er = 4.3) and its size is $30[mm]{\times}30[mm]$. It is designed to have characteristics that can be used in the frequency bands of 3.5 [GHz] and 5.2 [GHz], which are UWB / WAS frequency bands. The simulation was performed using CST Microwave Studio 2014. Simulation results show that the gain is 1.592 [dBi] at 3.5 [GHz] and 2.210 [dBi] at 5.2 [GHz]. The S-parameter also showed a result of less than -10 [dB] (WSWR 2: 1) in the desired frequency band. Microstrip antennas have been miniaturized, high performance, and light weight, and excellent and low cost systems are continuously being developed. In addition, many people use wireless local area network systems used in homes, companies, and public facilities. Since the UWB / WAS technology is proposed according to the development of the system and the demand increase, the antenna that satisfies the above conditions will be designed and the technology applicable to the system will be used more conveniently.

  • PDF

Copyright Protection for Fire Video Images using an Effective Watermarking Method (효과적인 워터마킹 기법을 사용한 화재 비디오 영상의 저작권 보호)

  • Nguyen, Truc;Kim, Jong-Myon
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.2 no.8
    • /
    • pp.579-588
    • /
    • 2013
  • This paper proposes an effective watermarking approach for copyright protection of fire video images. The proposed watermarking approach efficiently utilizes the inherent characteristics of fire data with respect to color and texture by using a gray level co-occurrence matrix (GLCM) and fuzzy c-means (FCM) clustering. GLCM is used to generate a texture feature dataset by computing energy and homogeneity properties for each candidate fire image block. FCM is used to segment color of the fire image and to select fire texture blocks for embedding watermarks. Each selected block is then decomposed into a one-level wavelet structure with four subbands [LL, LH, HL, HH] using a discrete wavelet transform (DWT), and LH subband coefficients with a gain factor are selected for embedding watermark, where the visibility of the image does not affect. Experimental results show that the proposed watermarking approach achieves about 48 dB of high peak-signal-to-noise ratio (PSNR) and 1.6 to 2.0 of low M-singular value decomposition (M-SVD) values. In addition, the proposed approach outperforms conventional image watermarking approach in terms of normalized correlation (NC) values against several image processing attacks including noise addition, filtering, cropping, and JPEG compression.

Development of an Unit Cost Modification Model for Proper Actual Cost Data in Small Building Construction Projects (소규모 건축공사의 적정 실적공사비 단가보정 모델 개발)

  • Kim, Kang-Shik;Hyun, Chang-Taek;Hong, Tae-Hoon;Jo, Seong-Min;Mun, Hyun-Seok
    • Journal of the Korea Institute of Building Construction
    • /
    • v.10 no.1
    • /
    • pp.81-89
    • /
    • 2010
  • Since 2004, the government has changedthe cost estimate system to one of an actual cost basis in order to calculate the optimum construction cost by reflecting changes in circumstance on the construction site in a timely manner. Currently, this is being applied to public construction work forover a billion won of actual cost data in estimation by contract unit cost. However, directly reflecting actual cost, which for large-sized construction work was originally an average unit cost, to a small building, entails the application of a low discount rate for the cost of materials, labor, etc. and therefore can frequently give rise to cases in which the actual cost of work performed exceeds the contract sum, which in turn causes problems such as decreased revenues, bad effectson business operation, productivity, etc. Therefore, to apply actual cost to small-sized construction work (less than a billion won), there should be a plan to modify unit cost in a manner that can reflect project scale, etc. in order to resolve the problem of unit cost application of actual cost to small-building construction projects. The unit cost modification model for proper actual construction cost in small-scale construction projects developed by this study will help to increase the relevant productivity and proper gain, preventing the aggravation of business operations. Organizations placing orders are also expected to be able to secure a more realistic construction cost in arranging the budget.

Wearable antenna for Body area Network

  • Lim, Eng Gee;Wang, Zhao;Lee, Sanghyuk
    • Journal of Convergence Society for SMB
    • /
    • v.3 no.2
    • /
    • pp.27-32
    • /
    • 2013
  • Wireless Body Area Networks (WBAN) have been made possible by the emergence of small and lightweight wireless systems such as Bluetooth, enabled devices and PDAs. Antennas are an essential part of any WBAN system and due to various technical requirements and physical constraints, careful consideration of their design and deployment is needed. This paper is proposing on the design of wearable antenna as parts of clothing to serve communications functions, such as tracking and navigation in health care applications. The substrates of the wearable antennas will be made from textile materials and since it is wearable, it should have a small size, be light weight, low maintenance, and unobtrusive. This proposed paper will also investigate the influence of different parameters for wearable antenna including types of textile/substrate to ensure that the antenna design satisfies WBAN requirements. The characteristics and behavior of the antenna need to adhere to specifications set by wireless standards and system technology requirements. This means that the transmitting and receiving frequency bands of the various units need to be chosen accordingly. Since there are restrictions on the level of power to which the human body can be exposed to, the antenna as well as other RF system components must be designed to meet these restrictions. Antenna gain, which directly affects power transmitted, is a critical parameter in ensuring power levels fall within the safety guidelines and so will be of primary importance in the design. The electromagnetic interaction between WBAN antennas and devices and the human body will also be explored.

  • PDF

Three Dimensional Implementation of Intelligent Transportation System Radio Frequency Module Packages with Pad Area Array (PAA(Pad Area Array)을 이용한 ITS RF 모듈의 3차원적 패키지 구현)

  • Jee, Yong;Park, Sung-Joo;Kim, Dong-Yong
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.38 no.1
    • /
    • pp.13-22
    • /
    • 2001
  • This paper presents three dimensional structure of RF packages and the improvement effect of its electrical characteristics when implementing RF transceivers. We divided RF modules into several subunits following each subunit function based on the partitioning algorithm which suggests a method of three dimension stacking interconnection, PAA(pad area array) interconnection and stacking of three dimensional RF package structures. 224MHz ITS(Intelligent Transportation System) RF module subdivided into subunits of functional blocks of a receiver(RX), a transmitter(TX), a phase locked loop(PLL) and power(PWR) unit, simultaneously meeting the requirements of impedance characteristic and system stability. Each sub­functional unit has its own frequency region of 224MHz, 21.4MHz, and 450KHz~DC. The signal gain of receiver and transmitter unit showed 18.9㏈, 23.9㏈. PLL and PWR modules also provided stable phase locking, constant voltages which agree with design specifications and maximize their characteristics. The RF module of three dimension stacking structure showed $48cm^3$, 76.9% reduction in volume and 4.8cm, 28.4% in net length, 41.8$^{\circ}C$, 37% in maximum operating temperature, respectively. We have found that three dimensional PAA package structure is able to produce high speed, high density, low power characteristics and to improve its functional characteristics by subdividing RF modules according to the subunit function and the operating frequency, and the features of physical volume, electrical characteristics, and thermal conditions compared to two dimensional RF circuit modules.

  • PDF

Effect of Ulmus davidiana Planch herbal acupuncture Solution on proinflammatory cytokine IL-$1{\beta}$ and $TF-{\alpha}$ a production in collagen-induced arthritis of rats

  • Jo, Young-Wook;Yoon, Jong-Hwa;Kim, Kyung-Ho;Lee, Seung-Deok;Kim, Kap-Sung
    • Journal of Acupuncture Research
    • /
    • v.22 no.2
    • /
    • pp.93-101
    • /
    • 2005
  • Objective: We have evaluated UDHA into the joint for its effectiveness on immune responses to CII in the rat CIA. In an attempt to gain further insight into the mode of action of UDHA, we also investigated the effects of UDHA on the incidence and development of arthritis in rat CIA with 2 different regimens: (1) started prior to a primary immunization, (2) started on the day of a primary immunization. Methods : Male rats were immunized with an emulsion of $200\;{\mu}g/100g$ of CII and complete Freund's adjuvant (CFA). The rats were then given intraperitoneal(i.p) stimulation of Ulmus davidiana Planch herbal acupuncture(UDHA) or saline during the experiment. Lymph node cells were obtained from rats 14 days after immunization and cultured in vitro with CII. When compared with rats treated with saline as control, UDHA at doses of more than $20\;{\mu}g/100\;g$ rat once a day for 7 days inhibited the ability of inguinal lymph node cells to produce T cell cytokines interleukin-$1{\beta}$, tumor necrosis $factor-{\alpha}$ $(TNF-{\alpha})$. When rats were injected intraperitoneally with SRBC, hemaglutination titers in UD-treated and control rats did not differ significantly when low doses of UD was given to rats. However, i.p injection of UD at doses of more than $10\;{\mu}g/100\;g/day$ for 7 days slightly suppressed antibody production. Results : The present results show that treatment with UDHA can inhibit the onset and development of arthritis and the immune responses to collagen. Conclusion: Therapeutic i.p injection with UD affect the clinical course of the disease and the immune responses to CII.

  • PDF

The Effects of Pharmacopuncture(Eugenia caryophyllata $T_{HUNB.}$) on the High Fat Diet-induced Obese ICR Mice (정향약침(丁香藥鍼)이 고지방 식이 유발 비만 백서(白鼠)에 미치는 영향)

  • Kim, Sung Jin;Lee, Hyun Jong;Lee, Bong Hyo;Lee, Yun Kyu;Lim, Seong Chul;Jung, Tae Young;Kim, Jae Soo
    • Journal of Acupuncture Research
    • /
    • v.30 no.3
    • /
    • pp.75-85
    • /
    • 2013
  • Objectives : The purpose on this study is to show the anti-obesity effect of Eugenia caryophyllata $T_{HUNB.}$ pharmacopuncture in mice fed a high fat diet. Methods : Male ICR mice were divided into three groups, which were fed a normal AIN diet(N), a high fat diet(CT), a high fat diet and injected with 50 mg/kg of Eugenia caryophyllata $T_{HUM.}$ pharmacopuncture(EC) for 8 weeks. Results : 1. The levels of body weight gains were significantly increased in CT compared with N and decreased in EC compared with CT. 2. The levels of absolute liver weight and adipose-tissue weight were significantly decreased in EC compared with CT. The levels of relative adipose-tissue weight were significantly decreased in EC compared with CT. 3. The levels of total cholesterol(TG), triglycerid(TC), high density lipoprotein(HDL) cholesterol and low density lipoprotein(LDL) cholesterol were significantly increased in CT compared with N and decreased in EC compared with CT. The levels of HDL/LDL ratio were shown there were no significant differences in all groups. 4. The levels of adiponectin in serum were remarkably decreased in CT compared with N and significantly increased in EC compared with CT. 5. The levels of measuring adipocyte number in adipose tissue was significantly decreased in CT compared with N and increased in EC compared with CT. Conclusions : These results suggest that Eugenia Caryophyllata $T_{HUNB.}$ has an anti-obesity effect in mice and that the effect is mediated by inhibition of fat gain.

Assessment of the Minimum Population Size for ex situ Conservation of Genetic Diversity in Aster altaicus var. uchiyamae Populations Inferred from AFLP Markers (AFLP 마커를 이용한 단양쑥부쟁이 개체군의 유전다양성 보전을 위한 최소개체군의 크기산정)

  • Kim, Chang-Kyun;Kim, Ho-Joon;Choi, Hong-Keun
    • Korean Journal of Environment and Ecology
    • /
    • v.25 no.4
    • /
    • pp.470-478
    • /
    • 2011
  • Aster altaicus var. uchiyamae is on the list of endangered species in Korea. Using amplified fragment length polymorphism (AFLP) markers, we investigated the genetic diversity within and among four populations (Guram, Dori Island, Samhap, and Danyang) of A. altaicus var. uchiyamae. We also present the collecting strategies that most efficiently capture the genetic diversity of A. altaicus var. uchiyamae. Four AFLP primer combinations produced a total of 936 bands, of which 934 (99.8%) were polymorphic. A high level of genetic diversity (PPB = 45.3%, h = 0.104, I = 0.168, hs = 0.108) was recognized within the populations of A. altaicus var. uchiyamae. A low degree of genetic differentiation ($G_{ST}$ = 0.075, ${\theta}^B$ = 0.079) was detected among the populations. In addition, analysis of molecular variance (AMOVA) showed that genetic variation was greater within populations (91%) than among populations (9%). These results indicate that the high rate of gene flow has played an important role in forming the present populations of A. altaicus var. uchiyamae. According to maximization strategy, 17, 16, and 11 individuals captured all of the genetic variation in Dori Island, Samhap, and Guram population, respectively. The determination the minimum population size of A. altaicus var. uchiyamae in terms of the genetic information is critical and thereby gain reliable decision support for ex situ conservation of the endangered species, A. altaicus var. uchiyamae.

A 12b 130MS/s 108mW $1.8mm^2$ 0.18um CMOS ADC for High-Quality Video Systems (고화질 영상 시스템 응용을 위한 12비트 130MS/s 108mW $1.8mm^2$ 0.18um CMOS A/D 변환기)

  • Han, Jae-Yeol;Kim, Young-Ju;Lee, Seung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.45 no.3
    • /
    • pp.77-85
    • /
    • 2008
  • This work proposes a 12b 130MS/s 108mW $1.8mm^2$ 0.18um CMOS ADC for high-quality video systems such as TFT-LCD displays and digital TVs requiring simultaneously high resolution, low power, and small size at high speed. The proposed ADC optimizes power consumption and chip area at the target resolution and sampling rate based on a three-step pipeline architecture. The input SHA with gate-bootstrapped sampling switches and a properly controlled trans-conductance ratio of two amplifier stages achieves a high gain and phase margin for 12b input accuracy at the Nyquist frequency. A signal-insensitive 3D-fully symmetric layout reduces a capacitor and device mismatch of two MDACs. The proposed supply- and temperature- insensitive current and voltage references are implemented on chip with a small number of transistors. The prototype ADC in a 0.18um 1P6M CMOS technology demonstrates a measured DNL and INL within 0.69LSB and 2.12LSB, respectively. The ADC shows a maximum SNDR of 53dB and 51dB and a maximum SFDR of 68dB and 66dB at 120MS/s and 130MS/s, respectively. The ADC with an active die area of $1.8mm^2$ consumes 108mW at 130MS/s and 1.8V.