• Title/Summary/Keyword: dual problem

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Sarcopenia: Nutrition and Related Diseases

  • Du, Yang;No, Jae Kyung
    • Culinary science and hospitality research
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    • v.23 no.1
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    • pp.66-78
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    • 2017
  • "Sarcopenia", sarcopenia is an old age syndrome, and used to describe the reduction of skeletal muscle. Initially, it was thought that sarcopenia was only a senile disease characterized by degeneration of muscle tissue. However, its cause is widely regarded as multifactorial, with neurological decline, hormonal changes, inflammatory pathway activation, declines in activity, chronic illness, fatty infiltration, and poor nutrition, all shown to be contributing factors. Skeletal muscle mass can be measured by a variety of methods, currently, the commonly used methods are dual-energy X-ray scanning (DXA), computer tomography (CT), magnetic resonance imaging (MRI), etc. Muscular skeletal disorders can also be assessed by measuring appendicular skeletal muscle (ASM), particularly muscle tissue content. At the same time, sarcopenia refers to skeletal muscle cell denervation, mitochondrial dysfunction, inflammation, hormone synthesis and secretion changes and a series of consequences caused by the above process and is a progressive loss of skeletal muscle syndrome, which can lead to the decrease of muscle strength, physical and functional disorders, and increase the risk of death. Sarcopenia is mainly associated with the aging process, but also related to other causes such as severe malnutrition, neurodegenerative diseases, and disuse and endocrine diseases associated with muscular dystrophy, and it is the comprehensive results of multi-factors, so it is difficult to define that sarcopenia is caused by a specific disease. With the aging problem of the population, the incidence of this disease is increasingly common, and seriously affects the quality of the life of the elderly. This paper reviews the etiology and pathogenesis of myopathy, screening methods and diagnosis, the influence of eating habits, etc, and hopes to provide reference for the diagnosis and treatment of this disease. At present, adequate nutrition and targeted exercise remain the gold standard for the therapy of sarcopenia.

Joint Polarization and Frequency Assignment Algorithm Based on Graph Theory (그래프 이론 기반의 편파 및 주파수 지정 알고리즘)

  • Koo, Bonhong;Chae, Chan-Byoung;Park, Sung-Ho;Park, Hwi-Sung;Ham, Jae-Hyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.8
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    • pp.954-957
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    • 2016
  • In cases of military communication plan, it often requires to find a proper solution for frequency assignment within feasible time. Minimizing the number of used resources are related to cost issue, hence it is a critical objective. When the dual polar antenna is used, the performance can be much developed by exploiting the polarization separation. In this paper, we propose an algorithm that assigns polarizations and frequencies within complexity of $O(N^2)$ based on the graph matching theory. We have verified that the proposed algorithm shows almost twice performance relative to the uni-polar frequency assignment algorithms and it approaches very closely to its theoretical optima.

Development of Long-Range RFID Reader System supporting Sensor Tag (센서태그를 지원하는 장거리 RFID 리더 시스템 개발)

  • Shin, Dong-Beom;Kim, Dae-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.6C
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    • pp.626-633
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    • 2009
  • ISO/IEC/WD 24753 defines new modem specifications for a long-range RFID communications and application protocol for a sensor tag system. According to the standard, the frequency offset of the tag is 4%. In general wireless communications systems, it is known that a coherent receiver is superior to a non-coherent receiver. However, if the frequency offset is large, it is difficult to restore the original data accurately with a coherent receiver, and the performance of a coherent receiver is easily degraded. In this paper, a non-coherent receiver structure is adopted to solve the frequency offset problem of long-range RFID communications. We designed a frequency estimation block to find an optimal frequency from the received signal with 4% frequency offset and proposed a start frame delimiter (SFD) detection algorithm to determine the start position of the payload. The frequency estimation block finds the optimal frequency from the received signal using 9-correlators. And the SFD detection block searches the received signal to find the start position of the payload with dual correlator. We implemented a long-range RFID reader with the proposed methods and evaluated its performance in a wired/wireless test network. The implemented long-range RFID reader showed more superior performance than the commercial RFID reader in terms of recognition range.

A Study on the Leakage Characteristic Evaluation of High Temperature and Pressure Pipeline at Nuclear Power Plants Using the Acoustic Emission Technique (음향방출기법을 이용한 원전 고온 고압 배관의 누설 특성 평가에 관한 연구)

  • Kim, Young-Hoon;Kim, Jin-Hyun;Song, Bong-Min;Lee, Joon-Hyun;Cho, Youn-Ho
    • Journal of the Korean Society for Nondestructive Testing
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    • v.29 no.5
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    • pp.466-472
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    • 2009
  • An acoustic leak monitoring system(ALMS) using acoustic emission(AE) technique was applied for leakage detection of nuclear power plant's pipeline which is operated in high temperature and pressure condition. Since this system only monitors the existence of leak using the root mean square(RMS) value of raw signal from AE sensor, the difficulty occurs when the characteristics of leak size and shape need to be evaluated. In this study, dual monitoring system using AE sensor and accelerometer was introduced in order to solve this problem. In addition, artificial neural network(ANN) with Levenberg.Marquardt(LM) training algorithm was also applied due to rapid training rate and gave the reliable classification performance. The input parameters of this ANN were extracted from varying signal received from experimental conditions such as the fluid pressure inside pipe, the shape and size of the leak area. Additional experiments were also carried out and with different objective which is to study the generation and characteristic of lamb and surface wave according to the pipe thickness.

Evaluation of Airflow Control Capability of Natural Ventilators with Various Dampers (자연환기 벤틸레이터의 댐퍼 형태별 환기량 조절능력 평가)

  • Kim, Tae-Hyeong;Ha, Hyun-Chul;Park, Seung-Chul
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.16 no.4
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    • pp.364-374
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    • 2006
  • Natural ventilation technique could be the substitute for or the complement to the local exhaust ventilation system in the sense of protecting work environment. Moreover, it has many strong points ; almost no mechanical parts, no energy use and no noise. If applied appropriately, it could have the very high ventilation rate and save a lot of energy expense. But, it depends on the outdoor environment, especially temperature and wind speed/direction. Predicting the capacity of natural ventilation is not an easy job because it comes from both buoyancy and wind effect. Another problem is too much flow through the ventilator especially in winter time due to too much difference between indoor and outdoor temperature. Thus some ventilators in industries are sealed by door or plastic sheet, resulting in bad work environment. Various types of dampers are used to control the flow rate through ventilators. The capabilities of flow control by damper has not been estimated. In addition, it was not tested whether the damper could obstruct the flow through ventilator when fully opened. To answer these questions, 4 types of dampers were tested by using computational fluid dynamics. 10 different configurations includes no damper, full open and half open. Flow rates were estimated and airflow fields were analysed to clarify the before-mentioned questions. The dual type damper was the best choice for controling the capability of ventilator. In addition, the upward grill type damper was the best for not obstructing the air flow when fully opened.

High power X-band SSPA Design using Gysel Power Combiner (Gysel 전력결합기를 이용한 고출력 X-band SSPA 설계)

  • Lee, Sang-Rok;Lim, Eun-Jae;Rhee, Young-Chul
    • The Journal of the Korea institute of electronic communication sciences
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    • v.9 no.4
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    • pp.425-432
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    • 2014
  • Necessity of compact X-band solid-state weather radar is required to provide weather data, which generate locally in a lot of Korea's mountainous area, rather than tube-type radar. Solid State Power Amplifier (SSPA) for using Dual-polarization method in weather radar is able to obtain desired high output by combining many low output power devices in parallel. Thus, Power combiner applying to high-output power amplifier has disadvantages such as path loss, ballast resistance problem by high frequency and high power, heat release. Therefore, In this paper we demonstrated the excellence of isolation, which is the result from modified Gysel power combiner. As a result, we designed X-band 250W solid state power amplifier with peak power 54dBm, 25% power efficiency for weather radar.

Application of Neural Network Control Algorithm and Maximum Power Tracking of Sun Photocell using Sunlight Sensor (태앙광 센서에 의한 태앙광 전지의 최대전력추적과 신경회로망 제어알고리즘 적용)

  • Yoo, Seok-Ju;Lee, Seong-Su;Park, Wal-Seo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.2
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    • pp.33-38
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    • 2010
  • Recently, photovoltaic generator system is widely extended by energy policy of the government. Add to this, high efficiency of photocell power generation is steady needed to sun tracking method. However sun tracking method is not widely extended by insufficiency of tracking technology. As method of solving this problem, this paper applied sunlight sensor and neural network control algorithm for maximum power tracking of sun photocell. Sun tracking sensor consists of one upright square pole and form light sensor of east, west, south, north on flat board. Sun tracking dual axes control is operated respectively by two motor. Motor control input is calculated by neural network control algorithm. The function of proposed control method is verified by sun tracking experiment of photocell generation. The sun tracking method of this paper is increased 32[%] efficiency more than fixed method.

Tapentadol: Can It Kill Two Birds with One Stone without Breaking Windows?

  • Chang, Eun Jung;Choi, Eun Ji;Kim, Kyung Hoon
    • The Korean Journal of Pain
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    • v.29 no.3
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    • pp.153-157
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    • 2016
  • Tapentadol is a novel oral analgesic with a dual mode of action as an agonist of the ${\mu}$-opioid receptor (MOR), and as a norepinephrine reuptake inhibitor (NRI) all in a single molecule. Immediate release (IR) tapentadol shows its analgesic effect quickly, at around 30 minutes. Its MOR agonistic action produces acute nociceptive pain relief; its role as an NRI brings about chronic neuropathic pain relief. Absorption is rapid, with a mean maximal serum concentration at 1.25-1.5 h after oral intake. It is present primarily in the form of conjugated metabolites after glucuronidation, and excretes rapidly and completely via the kidneys. The most common adverse reactions are nausea, dizziness, vomiting, and somnolence. Constipation is more common in use of the ER formulation. Precautions against concomitant use of central nervous system depressants, including sedatives, hypnotics, tranquilizers, general anesthetics, phenothiazines, other opioids, and alcohol, or use of tapentadol within 14 days of the cessation of monoamine oxidase inhibitors, are advised. The safety and efficacy have not been established for use during pregnancy, labor, and delivery, or for nursing mothers, pediatric patients less than 18 years of age, and cases of severe renal impairment and severe hepatic impairment. The major concerns for tapentadol are abuse, addiction, seeking behavior, withdrawal, and physical dependence. The presumed problem for use of tapentadol is to control the ratio of MOR agonist and NRI. In conclusion, tapentadol produces both nociceptive and neuropathic pain relief, but with worries about abuse and dependence.

Performance Analysis for Malicious Interference Avoidance of Backscatter Communications Based on Game Theory (게임이론 기반 백스케터 통신의 악의적인 간섭 회피를 위한 성능 분석)

  • Hong, Seung Gwan;Hwang, Yu Min;Sun, Young Khyu;Shin, Yoan;Kim, Dong In;Kim, Jin Young
    • Journal of Satellite, Information and Communications
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    • v.12 no.4
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    • pp.100-105
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    • 2017
  • In this paper, we study an interference avoidance scenario in the presence of a interferer which can rapidly observe the transmit power of backscatter communications and effectively interrupt backscatter signals. We consider a power control with a sub-channel allocation to avoid interference attacks and a power-splitting ratio for backscattering and RF energy harvesting in sensors. We formulate the problem based on a Stackelberg game theory and compute the optimal transmit power, power-splitting ratio, and sub-channel allocation parameter to maximize a utility function against the interferer. We propose the utility maximization using Lagrangian dual decomposition for the backscatter communications and the interferer to prove the existence of the Stackelberg equilibrium. Numerical results show that the proposed algorithms effectively maximize the utility, compared to that of the algorithm based on the Nash game, so as to overcome a malicious interference in backscatter communications.

Recent Advances in Artificial Insemination (AI) in Horses: Stallion Management, Processing and Preservation of Semen and Insemination Techniques

  • Yoon, Minjung
    • Journal of Embryo Transfer
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    • v.28 no.2
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    • pp.87-93
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    • 2013
  • The efficiency of artificial insemination (AI) for horses remains unsatisfactory. It is mainly because each process of AI causes a detrimental effect on semen quality. To sustain quality of semen properly, several factors including libido of stallions and sperm damage during sperm processing and preservation should be considered. Stallions with decent libido produce a high ratio of sperm to seminal plasma in their ejaculates, which is the ideal semen composition for maintaining sperm quality. Thus, to maximize the fertility rate upon AI, stallions should be appropriately managed to enhance their libido. Seminal plasma should have a positive effect on horse fertility in the case of natural breeding, whereas the effects of seminal plasma on both sperm viability and quality in the context of AI remain controversial. Centrifugation of semen is performed during semen processing to remove seminal plasma and to isolate fine quality sperm from semen. However, the centrifugation process can also result in sperm loss and damage. To solve this problem, several different centrifugation techniques such as Cushion Fluid along with dual and single Androcoll-E$^{TM}$ were developed to minimize loss of sperm and to damage at the bottom of the pellet. Most recently, a new technique without centrifugation was developed with the purpose of separating sperm from semen. AI techniques have been advanced to deliver sperm to optimal region of female reproductive tract at perfect timing. Recombinant equine luteinizing hormone (reLH) and low dose insemination techniques have been developed to maximize both fertility rate and the efficiency of AI. Horse breeders should consider that the entire AI procedure should be optimized for each stallion due to variation in individual horses for a uniformed AI protocol.