• Title/Summary/Keyword: Temeprature Control

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Development of Temperature Control System for Semiconductor Test Handler II - Controller Design (반도체 테스트 핸들러의 온도제어 시스템 개발 II - 제어기 설계)

  • 김재용;강태삼;이호준;선기상
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.77-80
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    • 1997
  • In this paper presented is a temperature controller for a semiconductor test handler. Using ARMAX model and least square method, the chamber model for the design of a controller is identified through experiment. With the identified model an LQG/LTR controller is designed. Experiment with a real test handler demonstrated good performance in that its overshoot is small and response time is fast.

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A development of multi-step neural network predictive controller (다단 신경회로망 예측제어기 개발)

  • 이권순
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.35C no.8
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    • pp.68-74
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    • 1998
  • The neural network predictiv econtroller (NNPC) is proposed for the attempt to mimic the function of brain that forecasts the future. It consists of two loops, one is for the prediction of output (NNP:neural network predictor) and the other one is for control the plant(NNC: neural network controller). The output of NNC makes the control input of plant, which is followed by the variation of both plant error and predictin error. The NNP forecasts the future output based upon the current control input and the estimated control output. The input and the output data of a system and a new method using evolution strategy are used to train the NNP. A two-step NNPC is applied to control the temeprature in boiler systems. It was compared with PI controller and auto-tuning PID controller. The computer simulaton and experimental results show that the proposed method has better performances than the other method.

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Changes in the Compositions of Amino Acids in the Rice Seedlings under Low Temperature (저온처리한 벼 유식물의 아미노산 조성의 변화)

  • 문병용
    • Journal of Plant Biology
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    • v.32 no.4
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    • pp.235-245
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    • 1989
  • The contents and the compositions of total free amino acids were investigated in the rice(Oryza sativa L. cv. Chuncheong) seedlings under low temperatures. Activities of some enzymes associated with the markedly changed amino acid content were also investigaetd. Under low temperature, the contents of soluble protein and the total free amino acids increased, while the content of total nitrogen decreased. Although asparagine+glycine were the most abundant amino acid speceis in the rice seedlings at the control temeprature, low temperature treatment for 3days brought about the decrease in their amount to about 60% level of the control plants. On the other hand, alanine showed the highest increase in the content among all the free amino acids, though glutamine, proline, asprtic acid, valine and tyrosine also increased after low temperature treatment. To eludicate the decrease of asparagine+glycine level under low temperature, the activities of asparagine aminotransferase and asparaginase which metabolize asparagine were investigated in the rice seedlings under low temperature. The activity of asparaginase increased markedly, while that of asparagine aminotransferase decreased under low temperatures. Therefore, it was suggested that asparaginase metabolizes asparagine predominatly in the rice seedlings under low temperatures.

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Degradation Behavior of Solder Joint and Implementation Technology for Lead-free Automotive Electronics (자동차 전장제품의 무연솔더 적용기술 및 솔더 접합부 열화거동)

  • Hong, Won Sik;Oh, Chul Min
    • Journal of Welding and Joining
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    • v.31 no.3
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    • pp.22-30
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    • 2013
  • Due to ELV banning, automotive electronics cannot use four kinds of heavy metal element (Pb, Hg, Cd, $Cr^{6+}$) from 2016. Therefore, this study was focused on degradation characteristics of Sn-3.0Ag-0.5Cu Lead-free solder joint with OSP and ENIG finsh under various reliability assessment method, as like to thermal shock test and high temeprature/high humidity test with test duration for cabin electronics. Also, we compared bonding strength degradation to other advanced research results of electronic control unit for engine room because of difference service temperature with mount location in automotive. Whisker growth phenomenon and mitigation method which were essentially consideration items for Pb-free car electronics were examined. Conformal coating is a strong candidate for mitigating whisker growth in automotive electronics. Necessary condition to adapt Pb-free in car electronics was shown.

Isolation and Analysis of Temperature Sensitive Mutants in Aspergillus nidulans (Aspergillus nidulans 온도감수성 돌연변이주의 분리 및 분석)

  • 박찬규;강현삼
    • Korean Journal of Microbiology
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    • v.16 no.3
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    • pp.111-121
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    • 1978
  • About 40 temperature-sensitive mutants have been isolated as a preliminary step to study the spore germination, the cell cycle, and the control of macromolecular synthesis in Aspergillus nidulans. To obtain temperature-sensitive mutants rapidly and effectively, the selective enrichment method using antifungal antibiotic nystatin was developed. Based on the data which had applied to the concentration of auxotrophic mutants by the earlier investigators, the optimal concentration and the time of treatment at the nonpermissive temeprature were determined as 50 to 100 units per ml and 4.5 hr., respectively. Out of 41 ts mutants assigned to the strain symbol PK, thirteen that seemed to be arrested at the earlystage of spore germination were subjected to the further cytological and genetic analysis. Elght of these mutants are able to form germ tube and five not. Staining with acid fuchsin for the 5PK strains shows that one irreversible mutant, PK6 strain able to form germ tube, accumulate mitotic spindle, being arrested in mitosis. Another PK15 and PK23 strain have more than one intact nucleolus without germ tube formation at the restrictive temperature. the temperature-senstive mutation in PK12 strain, the onlystrain which is able occurred in certain gene specific for the germination of spore. All of the ts markers are recessive and complement each other in heterokaryon between two different ts markers at the restrictive temperature.

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Effect of Elevated $\textrm{CO}_2$ and Temperature on the Seedling Characteristics in Green Pepper (Capsicum annuum L. cv, Soonjung) ($\textrm{CO}_2$인 농도 및 온도 환경이 고추의 묘소질에 미치는 영향)

  • 안종길;최영환
    • Journal of Bio-Environment Control
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    • v.11 no.2
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    • pp.51-55
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    • 2002
  • Green peppers (Capsicum annuum L. cv, Soonjung) were grown under different combinations of $CO_2$ concentration and temperature levels and examined on the effect of elevated $CO_2$ and temeprature on plant growth, carbon and nitrogen concentrations. Plant height was stimulated by elevated $CO_2$ levels at 20.3 and 22.6$^{\circ}C$. Leaf area and fresh weight were remarkedly increased by high $CO_2$ concentration at 22.6$^{\circ}C$. Dry weights of leaf, stem, root, and whole plant were increased as temperature increased at 611 ppm $CO_2$, but those values decreased at 22.6$^{\circ}C$ in 397 ppm $CO_2$ concentration. Elevated $CO_2$ increased plant growth by 1.5 times at 20.5$^{\circ}C$ and 22.6$^{\circ}C$. C/N ratio increased with increasing temperature under elevated $CO_2$ levels.

The effect of gap between ingot and crucible on the distribution of initial melt concentration in Bridgman crystal growth (Bridgman 결정성장시 장입 주괴와 도가니 사이의 틈이 용액이 초기농도에 미치는 영향)

  • Seung-Mo Chung;Man-Sug Kang;Zin-Hyoung Lee
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.4 no.2
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    • pp.169-177
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    • 1994
  • Dilute Al-Cu and Al-Mg alloys were solidified unidirectionally upward by Bridgman method. It is necessary that solute concentration of initial melt is uniform to be able to control the concentration of crystal. When solute concentration is not uniform, it can cause unusual macro-segregation in grown solid. A non-steady state solidification was observed where the solute concentration in the grown solid decreased with the progress of solidification, when a dilute Al-Cu melt with positive axial temeprature gradient was solidified. This was caused by leaking out of Cu-rich melt into the gap between ingot and crucible during melt-down and its sedimentation after complete melting. In the case of Al-Mg alloy, the solute concentration has a minimum in the middle of grown specimen because Mg-rich melt flowed down the gap between ingot and crucible and floated after complete melting. Uniform initial melt concentration can be achieved by the homogenization of the ingot or by the absence of the gap between ingot and crucible.

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Studies of Gangjung (4) - Relationship of Acceleration Storage and Room Temperature Storage of Insam (Ginseng) Gangjung - (강정에 관한 연구(4) - 인삼 강정의 가속저장과 실온저장과의 관계 -)

  • Lee, Sook-Kyung;Kim, Youn-Tae
    • Journal of Food Hygiene and Safety
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    • v.18 no.4
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    • pp.218-223
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    • 2003
  • This study was to carried out to estimate the relationship between acceleration storage and room temperature storage of gangjung (control unit) and dried insam gangjung (experiment unit), by acid value and peroxide value. The result were summarized as follows. : 1. Test for acid value of control unit, every 1 hour after acceleration storage is similar to each 7 days after room temperature storage is imilar to each 7.5 days after room temeprature storage. 2. Test for peroxide value of control unit, evry 1 hour after acceleration storage is similar to each 7.5 days after room temperature storage but to test peroxide value of experiment unit, every 1 hour after acceleration storage is imilar to each 7.7 days after room temperature storage. 3. In case of the oxidized flavor, control unit is not detected during storage stability but the experiment unit is detected unit is detected 1 hour ahead of acceleration storage than room temperature storage.

Effects of Oligosaccharide and Pseudomonas sp. on the Growth of Potted Kalanchoe During Summer Season (천연올리고당 및 Pseudomonas속 길항미생물의 단독 및 혼용처리가 고온기 칼랑코에 생육촉진에 미치는 영향)

  • Kim, Seong-Ja;Han, Tae-Ho;Chung, Soon Ju
    • Journal of Bio-Environment Control
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    • v.12 no.4
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    • pp.207-216
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    • 2003
  • Most severe problem in production of potted kalanchoe during summer season is retardation of growth caused by high temperature. The aim of this experiment was aimed to investigate the effects of natural products such as algin-oligosacchride and glucosamine oligosaccharide, plant growth promoting rhizovacteria such as Pseudomonas sp. B and Pseudomonas sp. D2, and AG-solution on the growth of potted kalanchoe under the different root zone temperature in the greenhouse. Growth characteristics in terms of plant height, leaf length, leaf width, leaf area, leaf weight, fresh weight of shoot and root and root length were recorded under three root zone temperatures (25$^{\circ}C$, 30$^{\circ}C$, 35$^{\circ}C$). In 25$^{\circ}C$, the mixed treatment of Pseudomonas sp. B and glucosamine oligosaccharide resulted in the best growth in terms of plant height, leaf area and root weight. In 3-$^{\circ}C$, glucosamine oligosaccharide treatment gave fair result in plant height and leaf weight, but the mixed treatemtn of Pseudomonas sp. D2 and algin-oligosaccharide showed better growth on leaf area and root weight. In 35$^{\circ}C$, the mixed treatment of Pseudomonas sp. B and glucosamine oligosaccharide could greatly improve the plant height, leaf area, leaf weight and root weight. These results demonstrated that the mixed treatment of natural products and microorganisms could overcome the detrimental effects caused by high temeprature in the production of kalanchoe.

Prevalence of Enteyobius vermiculuris infection and preventive effects of masts treatment among children in rural and urban areas, and children in orphanages (농촌, 도시 및 집단생활 아동의 요충 감염과 집단 구충에 의한 예방 효과)

  • Kim, Jong-Su;Lee, Hae-Yong;An, Yeong-Gyeom
    • Parasites, Hosts and Diseases
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    • v.29 no.3
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    • pp.235-244
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    • 1991
  • An epidemiological study and mass treatments of Enterobius vermicularis infection among children near Wonju area of Kangwon province were carried out. The children were divided into 4 groups according to their residing localities; children in the mountainous area, rural area, urban area and in orphanage. They were examined by adhesive cellotape anal swab technique, and egg positive rates were obtained. The rates of egg reduction and re-infection rates after repeated mass treatments were also observed. The results obtained were as follows: 1. The overall egg Positive rate of E. vermicularis in the first screening was 19.9% (251 out of 1, 262 examinees; 19.7% in males and 20.1% in females). The positive rates were 13.0% in the mountainous area, 11 9% in the rural area, 15.1% in the urban (medium-sized) area and 61.9% in orphanages. 2. The highest positive rates were observed in the kindergarten children, and 1st and 2nd grade children of primary schools (26.2~32.2%), and the lowest rate (13.6%) in 6-year grade children of primary schools. 3. Cumulative detection rates from 3 repeated anal swabs at 4~5 days interval were higher (70.8%) than those from single anal swabs (50.0~59.2%). 4. Out of the examinees who showed the highest cumulative positive rate (70.8%), about 39.2% were consecutively positive in 3 anal swabs. Among different groups of children, the higher the total egg detection rates (87.5%), the higher the consecutive positive rates (71.9%) . 5. A total of 2, 609 (male : female=1 : 12.4) worms were collected from 17 egg-positive cases treated with anthelinintics. The mean number of worms per child was 153 (range: 4-824) . 6. The egg-positive cases in several studied groups (180 children) were treated with anthelmintics 6 times at 3-week intervals. In this case, the overall positive rate was decreased from 54.8% to 2.2% at 15 weeks after the treatments, but no complete negative conversion was experienced. However, in a group of children (154 children) including egg Positive and negative cases who were both treated with anthelmintics at 3-week interval, a complete egg-negative conversion was observed in the 9th week after treatments. 7. The egg-detection rate in the brothers or sisters of egg Positive children was 70.0% (28 out of 40 examined), and the egg-positive rate according to the family unit was 69.7%. In summarizing the above results, it is concluded that Enterobius vermicularis infection is still highly prevalent among children in Korea, and that repeated mass treatments of more than 3 times will be effective for control of this infection.

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