• Title/Summary/Keyword: wet test

Search Result 788, Processing Time 0.029 seconds

A Study of Mechanical Properties of Underwater Wet Welding Electrode (습식 수중 용접봉의 기계적 성질에 관한 연구)

  • 김민남;김복인;한정동
    • Journal of Ocean Engineering and Technology
    • /
    • v.14 no.4
    • /
    • pp.56-61
    • /
    • 2000
  • This study has been performed for mechanical properties of underwater wet welding electrode with rolled steel (KR-RA) for ship structure, one kind (E 4313) of domestic covered arc welding electrode used in the air and two kinds (UWE-01, UWE-02) of underwater covered arc welding electrode experimentally developed on the same welding condition. The results obtained were as follows : The hardness value of underwater covered arc welding electrode (UWE-01) was about 8.3% lower than domestic covered arc welding electrode(E 4313) in heat affected zone of test of UWF-02 was lower about 4.5%. Tensile strengths of UWE-01 were about 0.9%, and those of UWE-02 were about 6.5% higher than those of domestic covered arc welding electrodes (E 4313) in test specimens. The impect value of UWE-01 were about 15.5%, and those of UWE-02 were about 21.7% highter than those of domestic covered arc welding electrodes(E 4313) in test specimens. So mechanical properties of the underwater arc welding electrode were improved by the composition ratios of covering materials.

  • PDF

The introduction of Engine Performance Test for Miniature Turbojet Engine considering humidity effects (습도 영향을 고려한 초소형 터보제트 엔진 성능시험 소개)

  • Lee, Bo-Hwa;Lee, Kyung-Jae;Yang, Soo-Seok;Kim, Yu-Il
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2010.11a
    • /
    • pp.335-338
    • /
    • 2010
  • The moisture in the atmosphere exerts a lot of influence upon Gas turbine engine performances. There is a noticeable influence of wet air at the summer sea level, high flight mach number and low engine rpm increasingly. An altitude Engine Test Facility is used to accomplish the engine performance tests at dry air condition and wet air condition, through which engine performance results is revealed. In the result, net thrust and specific fuel consumption measured -2.826% and 1.325%, respectively at wet air condition compared to dry air condition.

  • PDF

Load Carrying Capacity Evaluation of WPC Soundproof Panel Subjected to Vertical Loads (WPC 방음판의 수직하중에 대한 내하성능 평가)

  • Chang, Taesun;Lee, Il Keun;Kim, Chulhwan;Shim, Jaewon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2014.10a
    • /
    • pp.823-826
    • /
    • 2014
  • The weight of soundproof panels is an important consideration in the design of both panels and supporting structures. The soundproof panels in noise barriers have to carry their net weight in wet condition respectively the reduced weight and also the weight of the above installed panels in wet condition without showing any failing. In this study, a compression test and a flexural test were performed to determine the maximum vertical load which a wood plastic composites (WPC) panel can bear. In addition, the maximum loading number and height of WPC panels in a noise barrier were calculated for full, simple, and continuous support conditions.

  • PDF

A Study on the Development of Underwater Wet Welding Electrodes

  • Kim, Min-Nam
    • Journal of Ocean Engineering and Technology
    • /
    • v.17 no.4
    • /
    • pp.52-58
    • /
    • 2003
  • Underwater wet arc welds were experimentally performed on the KR-RA steel plate as base metal by using four different types of flux coated electrodes: KT33, UWEE, UWCS, and TN20, UWEE, the individually designed flux coated underwater electrode, had good operability when compared with other domestic terrestrial electrodes, and imported goods. The hardness value and the portion of martensite of HAZ were increased, by using a rapid cooling rate, Mechanical properties were also examined experimentally with a multi-pass butt-welding specimen test. The individually designed flux coated electrode UWEE could be used in practice for underwater wet welds.

A Study on the Development of Underwater Wet Welding Electrodes

  • Kim, Min-Nam
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
    • /
    • v.6 no.1
    • /
    • pp.75-81
    • /
    • 2003
  • Underwater wet arc welds were experimentally performed on the KR-RA steel plate as base metal by using four different types of flux coated electrodes: KT33, UWEE, UWCS, and TN20. UWEE, the individually designed flux coated underwater electrode, had good operability when compared with other domestic terrestrial electrodes, and imported goods. The hardness value and the portion of martensite of HAZ were increased, by using a rapid cooling rate, Mechanical properties were also examined experimentally with a multi-pass butt-welding specimen test. The individually designed flux coated electrode UWEE could be used in practice for underwater wet welds.

  • PDF

Comparative Study of Fluidized Bed-type and Assmann Psychrometer (유동층습도계와 아스만습도계의 비교 연구)

  • 강희찬;강민철
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.15 no.9
    • /
    • pp.779-785
    • /
    • 2003
  • The present work proposed a newly developed fluidized bed-type psychrometer that could be applicable to the high temperature and contaminant gases. The psychrometer is a device that test gas passes through the water in a glass bottle as a bubbly flow to obtain the adiabatic saturation temperature. A fluidized bed-type psychrometer was made and its characteristics were compared with the Assmann Psychrometer. The characteristic time was in the order of a hundred seconds, and decreased for the decrease of the mass of water and the increase of the air flow rate. The air flow rate and the insulation of the glass bottle were definitely important in the accurate measurement of the wet bulb temperature. The error in wet bulb temperature became less than 5 percent of the difference of dry and wet bulb temperatures if the air velocity in the glass bottle was greater than 1.5m/s.

Multilayer Coatings on Flexible substrate for Electromagnetic Shielding by Using Dry/Wet Hybrid Processes (건습식 혼합공정을 이용한 유연소재 상 전자파 차폐용 다층막 코팅)

  • Lee, Hoon-Seung;Lee, Myeong-Hoon
    • Journal of the Korean institute of surface engineering
    • /
    • v.50 no.5
    • /
    • pp.373-379
    • /
    • 2017
  • Dry processes like evaporation and sputtering in vacuum chamber are difficult to make a uniform, large area and high quality film on thin PET substrate because of PET degradation and bad adhesion. On the other hand, wet processes like electro or electroless plating have complex processes and require high environmental cost. In this study, we successfully prepared $2{\mu}m$ Zn/Cu/Ni multilayers coated on $12{\mu}m$ polyethylene terephthalate (PET) substrate by using dry-wet mixing processes. Their surface electric resistances were evaluated around $0.2{\Omega}$ by using 4 probe measurements. Furthermore, their corrosion resistance also evaluated by natural potential test and compared with other wet, dry and mixing process samples.

Quality Characteristics of Baked Rice Cake using Dry and Wet Rice Powder (습식과 건식 쌀가루 종류를 달리하여 구운 떡의 품질 특성)

  • Park, Young Mi;Jung, Hyo Sun;Yoon, Hye Hyun
    • Culinary science and hospitality research
    • /
    • v.23 no.7
    • /
    • pp.129-139
    • /
    • 2017
  • This study investigated the quality characteristics of baked rice cake using dry and wet rice flour. The moisture contents, color values, texture and sensory evaluation(attribute difference and acceptance) for the samples were tested. The moisture content of baked rice cake was the highest in rice cake baked with non- glutinous rice of dry type, and rice cake baked in dry type had weaker brownishness and therefore had higher brightness value compared to the rice cake baked in wet type. In relation to the texture, the hardness was found to be the highest in the rice cake baked with wet non- glutinous rice, and the rice cake baked with glutinous rice was found to be soft. The hardness was the lowest in both wet and dry glutinous rice, and was the highest in the wet non- glutinous rice. Attribute difference test of samples showed that, the rice cake baked with glutinous rice showed clear manifestation of springiness, moistness, adhesiveness, and gumminess (except for the harness). Although the cake baked with dry rice powder showed no significant difference, the dry glutinous rice flour was preferred the most. The rice cake baked with wet glutinous rice flour was preferred the most in terms of flavor, taste, texture, and overall acceptability.

Acoustic analysis of wet voice among patients with swallowing disorders (삼킴장애 환자의 wet voice 관련 음향학적 분석)

  • Kang, Young Ae;Koo, Bon Seok;Kwon, In Sun;Seong, Cheoljae
    • Phonetics and Speech Sciences
    • /
    • v.10 no.4
    • /
    • pp.147-154
    • /
    • 2018
  • Wet voice quality (WVQ) is a characteristic that appears after swallowing. Although the concept is accepted by many clinicians worldwide, it is nevertheless ambiguous. In this study, we investigated WVQ in patients with swallowing disorders using acoustic analysis. A total of 106 patients diagnosed with penetration-aspiration by the videofluoroscopic swallowing study (VFSS) were recruited. A voice recording of vowel /a/ was conducted before and after the VFSS, and an acoustic analysis was then performed using PRAAT. Voice after VFSS was used for a perceptual judgment and divided into two groups: the Wet group (48 patients) and the Non-wet group (58 patients). At the post-VFSS stage, the two groups displayed significant differences in many acoustic parameters including F0_SD, Jitter, RAP, Shimmer, APQ, HNR, NHR, FUF, DVB, and CPP. The parameter affecting judging wetness resulted into Jitter and NHR by the logistic regression test. At the pre-VFSS stage, the two groups differed significantly in many acoustic parameters including Intensity, Jitter, RAP, Shimmer, NHR, FUF, DVB, and CPP. Both pre-and post-VFSS, the mean values of all significant parameters, except Intensity, HNR, and CPP, were higher in the Wet group. According to pre-and post-VFSS, the two groups displayed interactions in many parameters (Intensity, F0_SD, Jitter, RAP, Shimmer, APQ, HNR, NHR, FUF, DVB, and CPP). In particular, Intensity increased in both groups after the VFSS, although the increase in the Non-wet group was greater. Based on these results, it was conjectured that the WVQ after swallowing resulted from the secretion effect of the mucous membrane due to the dry laryngeal characteristic of elderly patients, rather than aspiration resulting in food on the vocal cords.

Amount of bacteria over time according to the use of antibacterial and wet wipes behavior (항균티슈와 물티슈 사용에 따른 시간별 세균 수 변화의 차이)

  • Han, Su-Min;Kim, Eun-Ji;Seomoon, Hye-Ji;Lim, Su-Min;Han, Ji-Young;Koong, Hwasoo
    • Journal of Korean Dental Hygiene Science
    • /
    • v.5 no.1
    • /
    • pp.21-27
    • /
    • 2022
  • Background: This study was conducted to analyze the time for re-detection of bacteria after surface disinfection using wet wipes, isopropyl alcohol, and benzalkonium chloride antibacterial tissue and provide standards for re-execution of surface disinfection with wet and antibacterial tissues. Methods: Seven laptops were wiped with wet tissue and isopropyl alcohol and benzalkonium chloride antibacterial tissues. Test areas were rubbed with a sterile cotton swab at baseline and after 30, 60, and 120 min. After plating on a tryptic soy agar medium, the number of colonies was counted by culturing at 36.5℃ for 24 h. Results: The average number of bacterial colonies was 5.85 ± 4.33 before isopropyl alcohol wiping and nil after wiping. The average number of bacterial colonies was 12.28 ± 14.67 benzalkonium chloride wiping and nil after wiping. Before wiping with wet wipes, the average number of bacterial colonies on laptop surfaces was 3.42 ± 5.22. Bacteria decreased after wiping with wet wipes but increased again over time. Conclusions: Wet wipes can temporarily reduce bacteria but are unsuitable for removing bacteria.