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Current status, challenges and the way forward for dairy goat production in Europe

  • Morales, Francisco de Asis Ruiz;Genis, Jose Maria Castel;Guerrero, Yolanda Mena
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.8_spc
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    • pp.1256-1265
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    • 2019
  • The aim of this review is to show the evolution of the dairy goat sector in Europe from all perspectives. Starting from the current situation, the challenges and future potential of this livestock system are presented, as well as strategies to overcome the difficulties faced. Europe holds 1.9% of the world goat population and produces 15.1% of goat milk recorded worldwide. The goat species plays a fundamental economic, social and environmental role in many regions of Europe. The wide diversity of production systems and autochthonous breeds makes the sector very heterogeneous. In order to improve viability, a number of strategies need to be adopted to solve the current problems such as a low profitability, absence of generational change and a little or no recognition of the social and environmental role of the sector. Some strategies to improve the situation of the European goat sector include: i) generating market value that will recognise the diversity of the dairy goat sector (breeds, feeding models, derived products${\ldots}$); ii) promoting and raising awareness of the functional attributes of goat milk and derived products so as to increase consumption; iii) assigning an economic value to environmental and social functions; iv) improving working conditions through technological innovation to make goat farming more attractive to young people; and v) processing more milk into cheese or other dairy products in production areas.

A Study on Tourist Satisfaction of Rural Tourism Products in Southern Jiangsu Area of China

  • Shan YI;Xu YING
    • The Journal of Industrial Distribution & Business
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    • v.14 no.9
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    • pp.13-19
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    • 2023
  • Purpose: Rural tourism, as a green and sustainable new development method, has become a new economic growth point in China's rural revitalization. The current research on rural tourism has not formed a complete and mature theoretical system, especially the study of tourist satisfaction. This paper is based on the perspective of tourist satisfaction and takes rural tourism in southern Jiangsu, China as the research object. Starting from the current situation of rural tourism development in southern Jiangsu, it elaborates on the current situation of rural tourism development in southern Jiangsu. Research design, data and methodology: Through literature analysis, it is concluded that the factors that affect tourist satisfaction are divided into four major aspects: personal factors, perceived effect factors, destination experience factors, and social factors. Design a survey questionnaire from four aspects: diversity, safety, convenience, agreeableness, and draw conclusions through data analysis. Results: From the four dimensions of the survey, tourists pay more attention to the diversity, agreeableness, and convenience of rural tourism products. This requires increasing the development of tourism products and improving the richness and diversity of rural tourism products. Conclusions: Therefore, optimization measures such as continuously implementing local rural cultural construction, establishing brand effects, and increasing policy support have been proposed.

Noninvasive Testing for Colorectal Cancer Screening: Where Are We Now?

  • Jaeyoung Chun;Jie-Hyun Kim;Young Hoon Youn;Hyojin Park
    • Journal of Digestive Cancer Research
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    • v.11 no.2
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    • pp.85-92
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    • 2023
  • Colorectal cancer (CRC) is one of the most prevalent cancers and is the leading cause of cancer-related mortality worldwide. Based on the current screening guidelines by the American Cancer Society and Korean multi-society expert committee, CRC screening is recommended in asymptomatic adults starting at the age of 45 years. Fecal immunochemical test-based screening programs reduce the development of CRC and related mortality in the general population. However, this most popular CRC screening strategy demonstrates a crucial limitation due to modest diagnostic accuracy. Colonoscopy may be considered as an alternative primary method for CRC screening; however, its implementation can still be challenging due to concerns regarding invasiveness, low adherence, cost-effectiveness, and quality assurance. To overcome the limitations of current screening tests, innovative noninvasive tests for CRC screening have been developed with advances in molecular biology, genetics, epigenetics, and microbiomics for detecting CRC, which may enhance the approach to CRC screening and diagnosis in clinical practice in the near future. This review explores the emerging screening methods and discusses their potential for integration into current practice.

Implementation of Speed Limitation Controller Considering Motor Parameter Variation in High Speed Operation (모터 파라미터 산포를 고려한 고속 운전에서의 속도제한 제어기 구현)

  • Kim, Kyung-Hoon;Yun, Chul;Kwon, Woo-Hyen
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.11
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    • pp.1584-1590
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    • 2017
  • This paper presents a implementation method of reliable speed limitation controller considering motor parameter variation in high speed operation. In spinning process of drum washing machine, speed increase has to be limited when unallowable imbalance mass is detected. Otherwise, severe noise and vibration can happen because noise and vibration are proportional to imbalance mass. To detect imbalance mass, d-axis current magnitude is used. However, we have to compensate for back-emf and power supply variation by means of detecting them because d-axis current is affected by both of them. On the other hand, we have to carefully estimate back-emf because back-emf is affected by stator resistance variation and inverter voltage error. Stator resistance variation can happen by manufacturing process for mass production or temperature variation in running. And there are inverter voltage errors between command voltage from micro-computer to inverter and real voltage from inverter to motor because of rising and falling time delay and turn-on resistance of power semiconductor switch. To solve this problem, we propose 2-step align current injection method which is to inject step-wise current right before starting. By this method, we can simply obtain stator resistance by ratio of voltage without inverter voltage error and current, and we can measure inverter voltage error. So we can obtain more exact model current, and then by simple calculation with compensation gain, we can estimate more accurate motor back-emf. We show that this method works well. It is verified through experiments.

Critical Conduction Mode Bridgeless PFC Converter Based on a Digital Control (디지털 제어 기반의 경계점모드 브릿지리스 PFC 컨버터)

  • Kim, Tae-Hun;Lee, Woo-Cheol
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.12
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    • pp.2000-2007
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    • 2016
  • Generally, in order to implement the CRM(Critical Conduction Mode), the analog controller is used rather than a digital controller because the control is simple and uses less power. However, according to the semiconductor technology development and various user needs, digital control system based on a DSP is on the rise. Therefore, in this paper, the CRM bridgeless PFC converter based on a digital control is proposed. It is necessary to detect the inductor current when it reaches zero and peak value, for calculating the on time and off time by using the current information. However, in this paper, the on-time and off-time are calculated by using the proposed algorithm without any current information. If the switching-times are calculated through the steady-state analysis of the converter, they do not reflect transient status such as starting-up. Therefore, the calculated frequency is out of range, and the transient current is generated. In order to solve these problems, limitation method of the on-time and off-time is used, and the limitation values are varied according to the voltage reference. In addition, in steady state, depending on the switching frequency, the inductance is varied because of the resonance between the inductor and the parasitic capacitance of the switching elements. In order to solve the problem, inductance are measured depending on the switching frequency. The measured inductance are used to calculate the switching time for preventing the transient current. Simulation and experimental results are presented to verify the proposed method.

Discharging Voltage Control with Error Detecting for Search light of Ship (선박용 탐사조명 전원장치의 방전개시전압 제어와 조명 이상검출)

  • Park, Noh-Sik;Kwon, Soon-Jae;Lee, Dong-Hee
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.10
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    • pp.8-17
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    • 2008
  • This paper presents a stable lighting method for HID lamp for ship from initial discharging current limit with discharging voltage control. The output voltage of the proposed control scheme is boosted for ignition, and the charging voltage is decreased by the resistor discharging. The proposed controller fires the initial discharge at the designed discharging voltage to limit the discharge current. After the discharging, constant current controller is used for brightness in steady state. The proposed control scheme can limit the initial discharge current using the starting point control without a complex voltage controller. so it can improve the life-time of HID lamp and get a stable discharge from restricted the initial discharge current. In order to improve the protection of the system, a simple instantaneous error detecting circuit for open state and short state of HID lamp is used. The proposed error detecting of HID lamp can protect the power system of lamp control. The effectiveness of the proposed controller is verified from the experiments of practical 2.5[kW] HID search light for ship.

Leakage Current Waveforms and Spectrum Analysis on Polymer Insulator of EPDM under Salt fog (SALT FOG시 EPDM고분자애자의 누설전류파형과 스펙트럼분석)

  • 박재준;양태규
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2004.05b
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    • pp.500-504
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    • 2004
  • This research is about the result of leakage current waveform about the situation of surface leakage current and environmental changes(Salt fog, clean fog and rain) by EPDM polymer insulators' amount of salt. The researcher presents the result of changing about fundamental harmonic, 3rd harmonic and 5th harmonic from starting point of supplying power to flashover. In this study, researched environmental affects (clean fog, salt fog and .am) about surface aging of polymer insulators and used frequency spectrum of leakage current waveform to develop the diagnostic technique of surface aging. When amount of salt contents changed, surface aging stage and the degree of aging (distortion factor) about 3rd and 5th harmonir waveform on low frequency harmonic wave. The distortion factor which is harmonic percentage about basic harmonic is important pointer to evaluate the surface condition of polymer insulators.

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The art of reporter proteins in science: past, present and future applications

  • Ghim, Cheol-Min;Lee, Sung-Kuk;Takayama, Shuichi;Mitchell, Robert J.
    • BMB Reports
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    • v.43 no.7
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    • pp.451-460
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    • 2010
  • Starting with the first publication of lacZ gene fusion in 1980, reporter genes have just entered their fourth decade. Initial studies relied on the simple fusion of a promoter or gene with a particular reporter gene of interest. Such constructs were then used to determine the promoter activity under specific conditions or within a given cell or organ. Although this protocol was, and still is, very effective, current research shows a paradigm shift has occurred in the use of reporter systems. With the advent of innovative cloning and synthetic biology techniques and microfluidic/nanodroplet systems, reporter genes and their proteins are now finding themselves used in increasingly intricate and novel applications. For example, researchers have used fluorescent proteins to study biofilm formation and discovered that microchannels develop within the biofilm. Furthermore, there has recently been a "fusion" of art and science; through the construction of genetic circuits and regulatory systems, researchers are using bacteria to "paint" pictures based upon external stimuli. As such, this review will discuss the past and current trends in reporter gene applications as well as some exciting potential applications and models that are being developed based upon these remarkable proteins.

Speed Control of AC Servo Motor Using Adaptive Fuzzy-Sliding Observer (적응 퍼지-슬라이딩 관측기를 이용한 교류 서보 전동기 속도제어)

  • Kim, Sang-Hoon;Yoon, Kwang-Ho;Ko, Bong-Woon;Kim, Won-Tae;Kim, Gi-Nam;Nam, Moon-Hyon;Kim, Lark-Kyo
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.726-728
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    • 2004
  • In this paper, the gain of the observer is properly set up using the fuzzy control and Fuzzy-Sliding observer(FSQ) that have a superior transient characteristic and is easy to implement compared to the existing method is designed. It estimate the differentiation of the armature current directly using the armature current measured in the AC motor. It estimate the speed of the rotor using the differentiation. It is proposed speed sensorless control method using the estimated speed. Optimal gain of speed observer(Luenberger observer) was set up using the fuzzy control and adapted speed control of AC servo motor. To verify the performance of designed Fuzzy-Sliding observer, simulation compared with fixed speed observer gain of G.B Wang and S.S Peng's sliding observer is performed. Also, it was proved the excellence and feasibility of the proposed observer from the comparison test with a speed sensor and without a speed sensor which used a highly efficient drive and 400W AC servo motor starting system.

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Cigarette Smoking Habits among Teenage Girls Living in a Rural Community in Korea (일부 농촌지역 여고생의 흡연 행동 특성조사)

  • 임우경
    • Journal of Nutrition and Health
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    • v.33 no.7
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    • pp.755-762
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    • 2000
  • female smoking especially in the population of teenage girls is regarded as an important health problem as the young female smokers are increasing sharply. We surveyed 895 teenage girls(15-19 years of age) living in a rural community in Korea for their cigarette smoking habits and the relationship between smoking status of subjects demographic variables and view on other's smoking. Of the subjects 11.6% stated that they were currently smoking and 67.3% of current smokers began smoking regularly sometimes before high school. The average smoking period of current smokers waas 20.6$\pm$1.5 mounts and they smoked 7.5 cigarettes/day on an average. Their main reason for starting to smoke was curiosity. The parents attitude for their offspring was more undemocratic in smokers. Smokers had lower academic sachievement and they had the family system such as single parent more undemocratic in smokers. Smokers had lower academic achievement and they had the family sysstem such as single parent family or divorced parent family more often than did non-smokers. Smoking status of subjects was positively related to that of their parents siblings and friends respectively. Smokers accepted others' smoking more positively than did non-smokers. Above results show that cigarette smoking is prevalent among teenage girls living in a rural community and smoking of subjects are affected by demographic variables and their view on others' smoking. Therefore the prevention the prevention programs aimed at adolescent smoking should be started before middle school and they should be included all influencing environmental factors such as family school and mass media.

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