• Title/Summary/Keyword: 소음기

Search Result 2,492, Processing Time 0.032 seconds

Development of bolt quantity detector for productivity improvement of assembly line (조립라인의 생산성 향상을 위한 볼트 수량 검출기 개발)

  • Mim, Byeong-Ro;Kim, Duck-Ki;Jun, Yoo-Hea;Jung, Jun-Hee;Lee, Hwen;Yoo, Su-Ho;Cha, San-Lee;Lee, Dae-Weon;OH, Se-Bu
    • Proceedings of the Korean Society for Agricultural Machinery Conference
    • /
    • 2017.04a
    • /
    • pp.150-150
    • /
    • 2017
  • 조립라인에서 볼트의 수량을 정확하게 검출하는 장치는 작업속도의 향상 및 불량발생을 줄이기 위해 필요한 것이다. 현재 조립에 필요한 수량을 작업자의 시각에 의해 파악하고 있기 때문에 작업시간이 증가되고 있으며 특히 조립 과정 중 작업자의 실수로 볼트가 제품의 내부에 침투하여 제품의 소음, 성능저하 및 수명단축을 초래하고 있다. 본 연구에서는 작업자의 편의성 및 조립속도 향상을 위해 볼트를 감지하여 자동으로 수량을 검출하는 장치를 개발하였다. 볼트의 특성에 따라 볼트 선별부의 치수를 수정하면 되도록 하였다. 조립라인의 생산성을 향상시키기 위한 설계는 Auto CAD를 이용하였다. 조립라인의 공간 효율 증가를 위하여 볼트 수량 검출기의 가로${\times}$세로의 크기를 최소로 하여 $220{\times}360{\times}1170mm$로 설계하였다. 받침대는 $60{\times}60$ 프로파일을 이용하였고 다른 구성 부품은 SUS304 재질을 가공하여 조립하였다. 실험은 실험구 마다 100회 측정하여 평균값을 나타냈으며, 소수점은 시스템에 영향이 없기 때문에 절사하였다. Test 19-27 구간이 배출부가 가장 적게 구동하는 것으로 나타났다. 정렬부의 각도가 10, $15^{\circ}$의 경우는 볼트와 배출부의 마찰력이 증가하여 구동횟수가 증가한 것으로 판단된다. $20^{\circ}$이상의 각도에서는 볼트가 배출부에 안착하기 전에 하강하기 때문에 반복횟수가 증가한 것으로 판단된다. 따라서 최적의 정렬부 각도는 $20^{\circ}$로 나타났다. 볼트의 지름이 3, 5, $7{\phi}$ 일 때 정렬부의 각도에 따른 정렬부의 반복횟수에 대한 결과 값을 한 결과 $20^{\circ}$에서 정렬부의 구동횟수가 가장 적은 것 으로 나타났다. 정렬부의 각도가 큰 경우 구동에 의한 볼트와의 운동에너지의 증가로 반복횟수가 증가한 것으로 판단된다.

  • PDF

Application of CFD Simulation to Cooling System Design of Agricultural Products Processing Center Workplace (농산물산지유통센터 작업장의 냉방 설계를 위한 CFD 시뮬레이션 적용)

  • Kwon, Jin-Kyung;Lee, Sung-Hyun;Moon, Jong-Pil;Lee, Su-Jang;Kim, Keyong-Won
    • Journal of Bio-Environment Control
    • /
    • v.19 no.4
    • /
    • pp.195-202
    • /
    • 2010
  • Cooling air-conditioning of APC (Agricultural Products processing Center) workplace is important to improve the working environment in the summer season. As existing cooling systems for air-conditioning of whole workplace are inefficient because of their high equipment operating costs, relatively inexpensive cooling system is required. The objectives of this study were to simulate the thermal flow fields in APC workplace having the positive and negative pressure type fan and pad systems and spot cooling system by using CFD software (FLUENT, 6.2) and estimate the cooling effectiveness of respective cooling systems. The results showed that the negative pressure type fan and pad system was inappropriate for the present APC workplace because of excessive outside air influx from open gateway and the positive pressure type fan and pad system created relatively low temperature field but non-uniform velocity field at worker positions. The spot cooling system could supply cool air to worker positions with relatively constant air velocity and temperature.

A Study on the Determination of Slot's Number of Rotor to Reduce Noise and Vibration and Design the 3-Phase Induction Motor Considering Kinetic Energy in Flywheel Energy Storage System (운동 에너지를 고려한 Flywheel Energy Storage System 설계와 진동 저감을 위한 3상 유도기의 슬롯수 산정에 관한 연구)

  • Ryu, Jae Ho;Kim, Hui Min;Lee, Chee Woo;Park, Gwan Soo;Jeong, Dong Wook
    • Journal of the Korean Magnetics Society
    • /
    • v.27 no.1
    • /
    • pp.1-8
    • /
    • 2017
  • Flywheel Energy Storage System (FESS) is composed by flywheel generating rotating potential energy and motor/generator set charging and discharging electric potential energy. The flywheel and motor/generator is connected by rotating shaft. And torque characteristics of motor/generator part can influence charging and mechanical traits of FESS. This paper analyze about motor/generator design method of 5 [kWh] FESS and torque ripple, harmonic effects by change of slots. At First, this paper proposes a method to estimate the flywheel size and the rotor size of the motor from the the rotational kinetic energy by inertia of FESS. The number of induction motor rotor slots for torque ripple reduction in the high speed operation region is selected. This paper performs to reduce the noise and vibration of the flywheel composed of coaxial with motor/generator and flywheel and realize the high efficiency.

The Performance Evaluation of the Adaptive UPC Mechanism in ATM (ATM망에서의 적응적 UPC 메커니즘의 성능 평가)

  • 안옥정
    • Proceedings of the Korea Society for Simulation Conference
    • /
    • 1994.10a
    • /
    • pp.11-11
    • /
    • 1994
  • 트래픽의 흐름을 조절하고 ATM 네트워크 자원의 사용을 최적화하기위해서는 폭주로 인한 성능 저하를 막기 위한 적절한 제어가 필요하다. 기존의 사용자 감시 제어(UPC) 메커니즘이 네트워크의 상황과는 관계없이 매우 불안정한 예방적 기능만을 수행하였고, qvj로 인해 셀 지연을 가중시키는 한계점을 갖고 있었다. 본 논문은 OAM 셀을 이용하여 네트워크의 상태에 따라 능동적으로 반응하는 적응적 사용자 감시 제어 메커니즘을 제안하고ㅡ 버퍼로 인한 지연을 고려하여 서비스의 한층 더 높이고자 한다. 제시한 사용자 감시 제어방식은 OAM 셀이 주는 정보를 바탕으로 네트워크 내의 상황을 판단하여 사용자가 요구한 서비스의 질을 고려할 수 있도록 리키율과 버퍼의 문턱값을 조정하였다. 네트워크가 분주시에는 리키율을 낮추고 버퍼를 줄여서 네트워크 내에 유입되는 셀을 막는 역할을 하고 네트워크가 한가할 때는 리키율을 높히고 버퍼를 늘여서 빠르게 네트워크 내로 셀이 유일도리 수 있\ulcorner 한다. 폭주 발생 시에는 셀의 유입을 막고 푹주 상태가 해결될때까지 스페이서의 작동을 멈춘다. 본 논문에서 제시한 사용자 감시 제어 메커니즘의 트래픽 소스 모델은 IPP로 모델링하였고, 트래픽은 음성과 고속 데이터를 중심으로 시뮬레이션하였다. 음성과 고속 대이타 각각의 경우에 시뮬레이션한 결과를 기존의 방식과 비교, 분석한 결과에서 음성에서는 버퍼지연이 대폭 줄였고 고속 데이터인 경우에는 셀 손실율이 줄어드는 것을 볼 수 있었다. 따라서 제시한 방식에 의해 사용자가 요구하는 서비스의 질을 유지하면서 동시에 네트워크의 자원을 효율적으로 사용하였음을 알 수있었다.에 적합한가를 고찰하였다.베이터에 의한 아파트의 소음 및 진동에 관하여 그 현황, 원인 그리고 대책에 관한여 논하고자 한다.감 방법을 연구하였고, T.Sakai는 5자유도 모델을 이용하여 엔진 공회전시 발생하는 치타음에 대해 이론과 실험을 통해 해석하고, 엔진 회전수 변동, 클러치 특성, 변속기의 드래그(drag) 토크의 영향과 치타음 저감을 위한 개선된 클러치 특성을 제시하였다. 이 외에도 Thomas C.T.와 E.P.Petkus는 특정 차량에 대한 동력전달계의 비틀림 진동 현상에 대해 연구하였다. 이러한 연구들로 볼 때, 자동차 동력전달계에서 발생하는 진동은 이론과 실험을 통해 그 해석이 가능하며 설계에 매우 유용하게 이용되고 있음을 알 수 있다. 따라서, 본 연구는 4 실린더 4 싸이클 1.5 L 엔진을 장착한 경승용차의 실차 주행실험을 통해 가속 페달의 급조작에 따른 차체의 종진동 현상을 측정하고, 엔진-변속기-타이어-차체의 반환정계 4자유도 진동모델로 시뮬레이션을 수행하여 실차 주행실험의 결과치와 비교, 분석한 후 클러치 비틀림 특성을 비롯한 자동차 동력전달계의 각 설계인자들이 차체의 종진동에 어떠한 영향을 미치는가를 해석하고자 한다.be presented.LIFO, 우선 순위 방식등을 선택할 수 있도록 확장하였다. SIMPLE는 자료구조 및 프로그램이 공개되어 있으므로 프로그래머가 원하는 기능을 쉽게 추가할 수 있는 장점도 있다. 아울러 SMPLE에서 새로이 추가된 자료구조와 함수 및 설비제어 방식등을 활용하여 실제 중형급 시스템에 대한 시뮬레이션 구현과 시스템 분석의 예를 보인다._3$", chain segment,

  • PDF

Effects of Taeumin, Soeumin and Soyangin Prescriptions on the Adipocyte Induced by Gold Thioglucose in the Rat (태(太)·소음인(少陰人), 소양인(少陽人)의 처방(處方)이 Gold thioglucose로 유발(誘發)된 백서(白鼠)의 비만병(肥滿病)에 미치는 효과(效果))

  • Kim, Kyung-Yo
    • Journal of Sasang Constitutional Medicine
    • /
    • v.8 no.1
    • /
    • pp.295-317
    • /
    • 1996
  • It is researched to elucidate the effects of Taeumjowuitang(TE,太陰調胃湯), Sibimikwanjungtang(SE, 十二味寬中湯) and Yangkeogsanwhatang(SY,凉膈散火湯) on the obesity induced by gold thioglucose and the differentiation and growth of preadipocyte 3T3-L1 in the mouse. The result were as follows: 1. TE,SE and SY extracts improved the blood level of transaminase in the obese mouse induced by gold thioglucose. 2. TE,SE and SY extracts inhibited the increase of liver fat and body fat in the obese mouse induced by gold thioglucose. 3. TE,SE and SY extracts inhibited the increase of body weight in the obese mouse induced by gold thioglucose. 4. TE,SE and SY extracts inhibited the growth of undifferentiate preadipocyte 3T3-L1. 5. TE,SE and SY extracts showed inhibitory effect on the differentiation of preadipocyte 3T3-L1. The above results suggest that the TE,SE and SY extracts may be used on the obesity induced by the overgrowth and differentiation of adipocyte, and the accumulation of fat in liver and body.

  • PDF

The Evaluation of IL-8 in the Serum of Pneumoconiotic patients (진폐증 환자에서의 혈청내 IL-8 농도)

  • Ahn, Hyeong Sook;Kim, Ji Hong;Chang, Hwang Sin;Kim, Kyung Ah;Lim, Young
    • Tuberculosis and Respiratory Diseases
    • /
    • v.43 no.6
    • /
    • pp.945-953
    • /
    • 1996
  • Background : Many acute and chronic lung diseases including pneumoconiosis are characterized by the presence of increased numbers of activated macrophages. These macrophages generate several inflammatory cell chemoattractants, by which neutrophil migrate from vascular compartment to the alveolar space. Recruited neutrophils secrete toxic oxygen radicals or proteolytic enzymes and induce inflammatory response. Continuing inflammatory response results in alteration of the pulmonary structure and irreversible fibrosis. Recently, a polypeptide with specific neutrophil chemotactic activity, interleukin-8(IL-8), has been cloned and isolated from a number of cells including : monocytes, macrophages and fibroblasts. IL-1 and/or TNF-${\alpha}$ preceded for the synthesis of IL-8, and we already observed high level of IL-1 and TNF-${\alpha}$ in the pneumoconioses. So we hypothesized that IL-8 may be a central role in the pathogenesis of pneumoconiosis. In order to evaluate the clinical utility of IL-8 as a biomarker in the early diagnosis of pneumoconiosis, we investigated the increase of IL-8 in the pneumoconiotic patient and the correlation between IL-8 level and progression of pneumoconiosis. Method : We measured IL-8 in the serum of 48 patients with pneumoconiosis and 16 persons without dust exposure history as a control group. Pneumoconiotic cases were divided into 3 groups according to ILO Classification : suspicious group(n=16), small opacity group(n=16) and large opacity group(n=16). IL-8 was measured by a sandwich enzytne immunoassay technique. All data were expressed as the $mean{\pm}standard$ deviation. Results: 1) The mean value of age was higher in the small opacity and large opacity group than comparison group, but smoking history was even. Duration of dust exposure was not different among 3 pneumoconiosis groups. 2) IL-8 level was $70.50{\pm}53.63pg/m{\ell}$ in the suspicious group, $107.50{\pm}45.88pg/m{\ell}$ in the small opacity group, $132.50{\pm}73.47pg/m{\ell}$ in the large opacity group and $17.85{\pm}33.85pg/m{\ell}$ in the comparison group. IL-8 concentration in all pneumoconiosis group was significant higher than that in the comparison group(p<0.001). 3) IL-8 level tended to increase with the progression of pneumoconiosis. Multiple comparison test using Anova/Scheffe analysis showed a significant difference between suspicious group and large opacity group(p<0.05). 4) The level of IL-8 was correlated with the progression of pneumoconiosis(r=0.4199, p<0.05). Conclusion : IL-8 is thought to be a good biomarker for the early diagnosis of pneumoconiosis.

  • PDF

A CLINICAL STUDY OF THE TYPE OF DISEASE AND SYMPTOM ACCORDING TO SASANG CONSTITUTION CLASSIFICATION (체질진단분류(體質診斷分類)에 따른 질병(疾病) 및 증상유형(症狀類型)에 관한 임상적(臨床的) 연구(硏究) II (문진표를 중심으로))

  • Kim, Young-woo;Kim, jing-weon
    • Journal of Sasang Constitutional Medicine
    • /
    • v.11 no.1
    • /
    • pp.119-135
    • /
    • 1999
  • The object of this study is 196 patients who had been treated in the Oriental Medical Hospital at Dong Eui Medical Center during 33 months from January 1996,3 to June 1998,11. We proceeded the judgment of Sasang Constitution by 'Questionnaire of Sasang Constitution Classification(I)' and 'Questionnaire of Sasang Constitution Classification II(QSCCII)'. The following conclusion were made in comparison with Sasang Constitution and Questionnaire about disease and style of symptoms. 1. The subject of "increase of the weight of a body(gain weight), sweatier, the body swelled out, a lame pain, more like fat food, more like salty food", has significant differences in sasang constitution classification. The frequency of Taeeum group is more than that of Soeum group and Soyang group. 2. The subject of "the complextion is bas, uncomfortable feeling in the throat, insomnia, loss of appetite, apt to be fatigued easily, gastralgia what is not connected with food, diarrhea, headache, menorrhalgia, less like fat food, more like fresh food", has significant differences in sasang constitution classification. The frequency of Soeum group is more than that of Taeeum group and Soyang group. 3. It has not significant differences, but the frequency of Soyang group is more than that of Taeeum group and Soeum group in the subject of "the cough in the disease of the respiratory organs, hypomotility of the joint in the disease of the musculo-skeletal systems, menoxenia like menorrhagia and menostaxia and itching sensation of genitals in the disease of the gynecological organs, itching or boil in the dermatological disease", and fewer in the cardio-vascular disease, urinary disease and hematic disease. The frequency of Soeum group is more than that of Taeeum group and Soyang group in the subject of "the general disease of the digestive organs, uncomfortable feeling or pain of the throat in the disease of the respiratory organs, the general hematic disease, numbness or pain of the musculo-skeletal disease, psychical disease in the psychoneurotical disease, menorrhalgia, a lump of the breasts, leukorrhea in the gynecological disease, eruption or urticaria in the dermatological disease, the general visual and auditory disease". The frequency of Taeeum group is more than that of Soyang group and Soeum group in the subject of "a hoarseness in the disease of the respiratory organs, A lame pain of the musculo-skeletal disease, neurotical disease in the psychoneurotical disease, eruption or urticaria in the dermatological disease", and fewer in the the gynecological disease.

  • PDF

Effects of Noise and Vibration on Oxygen Consumption and Ammonia Excretion in Cultured Catfish (Silurus asotus) (양식장에서 사육하는 메기 (Silurus asotus)의 산소소비 및 암모니아 배설에 미치는 소음진동 영향)

  • Hur, Jun Wook;Lee, Jeong Yeol;Joo, Jin Chul
    • Ecology and Resilient Infrastructure
    • /
    • v.5 no.2
    • /
    • pp.105-109
    • /
    • 2018
  • The main objective of this investigation was to examine oxygen consumption and ammonia excretion within cultured catfish, Silurus asotus ($22.9{\pm}0.9cm$, $100.7{\pm}11.7g$ n = 30) by noise and vibration stress in aquaculture farm. The vibration of 48, 58 and 68 dB (V) and noise of $77.6{\pm}1.8dB$ (A) from an electric vibrator was turned on for 15 minutes during each hour each day(0800-1800) for 11 days experimental period. The oxygen consumption (OC) of S. asotus the beginning of the experiment (0 day) in 58 dB group after 1, 5, 9 and 11 days was decreased 21.8, 30.2, 36.0 and 53.2%, respectively. In 68 group after 1, 7 and 11 days was decreased 22.7, 35.1 and 57.7%, respectively. The OC decreased exponentially and the relationship between them was expressed as OC = 0.374D + 90.762 ($r^2=0.048$) at 48 dB, OC = -3.581D + 89.520 ($r^2=0.831$) at 58 dB and OC = -4.109D + 90.907 ($r^2=0.884$) at 68 dB. Ammonia excretion (AE) of the beginning of the experiment in 48, 58 and 68 groups after 1 day was increased by 34.8, 51.8 and 63.2%, respectively, but it was decreased significantly from 3 to 11 days. The AE increased exponentially and the relationship between them was expressed as AE = -1.646D + 115.915 ($r^2=0.265$) at 48 dB, AE = -8.230D + 122.132 ($r^2=0.750$) at 58 dB and AE = -7.086D + 123.690 ($r^2=0.614$) at 68 dB.

A Study on the Symptomatic-pharmacology(病證藥理) Sasang Constiution (사상인(四象人)의 체질병증약리(體質病證藥理)에 관한 고찰(考察))

  • Song, Il-byung
    • Journal of Sasang Constitutional Medicine
    • /
    • v.10 no.2
    • /
    • pp.1-14
    • /
    • 1998
  • 1. Purpose : The correct constitutional diagnosis and the accurate prescription are very important in clinical application of Sasang Constitutional Medicine. Lee Je-ma emphasized that symptom is the best clue to diagnose constitution in "DongYi Suse Bowon". After research the characteristics of each constitution's symptoms and the backgrounds of constitutional prescriptions, this paper is to know the correct clinical application of Sasang Constitutional Medicine. 2. Method : Through the clinical applications of "DongYi Soose Bowon" and "Dongyi Sasang Sinpeun", the characteristics of constitutional symptoms and the application of prescription were researched 3. Results & Conclusions 1) The symptoms of Sasang Constitutional Medicine were came from the Hyung-Sang Medicine(形象醫學) which were important to mind-body equally and from the summarizing spirit of four Qi such as Warm-Hot-Cool-Cold(溫熱凉寒) 2) The symptoms of Soeumin and Soyangin are the Cold-Hot symptoms of ingestive food(水穀) and the treatment of symptoms is to control the ascent-descent of up and down. The symptoms of Taeumin and Taeyangin are the Warm-Cool symptoms of Qi-Yack(氣液) and the treatment of symptom is to control the unfasten-fasten of interior and exterior. 3) The symptoms of Taeyangin are 'Weak Lower part and Firm Upper part symptom'(下虛上實病證) and 'Blood and Yack Exhasted Symptom'(血液俱耗病證), the symptoms of Soeumin are 'Fall Down Symptom'(下陷病證) and Stomach Cold Symptom(胃寒病證), the symptoms of taeumin is 'Dryness Fever Symptom'(燥熱病證) and 'Interior Fever Symptom'(燥熱病證), the symptoms of Soyangin is 'Fire Fever Symptom'(火熱病證) and 'Interior Fever Symptom'(燥熱病證). 4) The characteristics of sasang constitutional symptoms are the exterior-interior symptoms classified with nature-emotion and cool-hot, the inclusive control of exterior-interior symptoms with healthy energy, and the classification of ingestive food symptoms and Qi-Yack symptoms. 5) The characteristics to treat symptoms are the classification of seriousness and obedience, the use herbs according to each constitutions, and inclusive symptoms control.

  • PDF

A Study on the adequate Aggregate Selection of the Exposed Aggregate PCC Pavements (골재노출 콘크리트포장의 적정 골재 선정에 대한 연구)

  • Kim, Young-Kyu;Chae, Sung-Wook;Lee, Seung-Woo;Yoo, Tae-Seok
    • International Journal of Highway Engineering
    • /
    • v.9 no.4
    • /
    • pp.117-127
    • /
    • 2007
  • The exposed aggregate PCC(EAP) pavements have been successfully used in Europe and Japan as low-noise pavements. Coarse aggregate are exposed on the pavement surface texture of EAP by removing mortar of surface. The pavement surface texture should maintain not only low-noise characteristic but also adequate skid resistance level during the performance period. Skid resistance decreased with wearing and polishing of tire and pavement surface due to the repetition of tire-pavement contact. Since the tires mainly contact the exposed coarse aggregate, the shape and rock type of coarse aggregate significantly influence wearing and polishing of EAP pavements. The test for resistance to abrasion coarse aggregate by use of the Los Angeles machine(KS F 2508) and the method of test for resistance to abrasion coarse aggregate by use of the Accelerated Polishing Machine(ASTM D 3319-90) are generally used to evaluate polishing characteristics of aggregate. In this study, polishing of coarse aggregate of different five rock types were evaluated by KS F 2508(LA abrasion test) and ASTM D 3319-90(PSV method). The results of LA abrasion test and PSV method were contrary to each other. Since LA abrasion test is estimated the quantity of abrasion by the impact of aggregate, it may not be adequate to evaluate the polishing of aggregate by the repetition of tire. In the case of PSV method, the resistance of polishing is estimated the skid resistance variation of polished aggregate after repetition of tire. The PSV method is adequate for the evaluation on polishing of coarse aggregate. From the test results of PSV method, it was founded that rock type, specific gravity, coarse aggregate angularity, flat or elongated particles in coarse aggregate are significant to the resistance characteristic of coarse aggregate.

  • PDF