• Title/Summary/Keyword: Test Effort

Search Result 988, Processing Time 0.027 seconds

Characterization of Live Fire Load in Buildings - Heat Release Characteristics of Typical Live Fire Load in Post Office Building - (건축물의 적재가연물 특성에 관한 연구 -우체국 적재가연물의 연소성상 -)

  • Nam, Dong-Gun;Yuji, Hasemi;SaKong, Seong-Ho;Jung, Jong-Jin
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 2008.04a
    • /
    • pp.7-10
    • /
    • 2008
  • Heat release characteristics of live fire load are an important parameter for performance oriented fire safety design of a building. While investigations have been carried out on the fire load and its burning behavior in office, residential and commercial buildings and so on, little effort has been paid for the rational treatment of fire load in post office buildings in Japan. In this report, burning behavior of typical combustible objects in post office buildings are studied by measuring heat release rates of plastic palettes with and without postal envelopes or packages and special containers loading numbers of palettes. The test results suggest that dynamic heat release rate is highly dependent on the condition of palettes especially if they load appropriate amount of postal envelopes or not.

  • PDF

The Quality Evaluation on Resistance Spot Welding of 2024 Aluminum Alloy and Zinc Coated Steel (2024 Al합금과 아연도금강판의 점용접에 관한 품질평가)

  • 허인호;이철구;채병대
    • Journal of Welding and Joining
    • /
    • v.19 no.4
    • /
    • pp.379-383
    • /
    • 2001
  • Resistance spot welding has been widely used in the sheet metal joining processes because of low cost, high productivity and convenience. Recently, automobile and aerospace industries are trying to replace partly steel sheets with aluminum alloy sheets. But in the case of dissimilar materials, to apply resistance spot welding has been known to be very difficult owing to the effect of melting temperature. On this study, an effort was made to apply spot welding of dissimilar sheet metals, 2024 aluminum alloy and zinc coated steel sheet, evaluate the spot weld quality with tensile-shear strength test and nondestructive evaluation technique, C-scan image methodology. In this study results, as the current below 11 kA, melting of materials is not achieved well. Also as the current exceeds to 13.5 kA, the more spatters happen at welded zone and tensile-shear strength lowered. So, the feasibility of C-scan image technique proposed in the study is found to be suitable evaluation method for resistance spot weldability.

  • PDF

Verification on Damage Calculating Method of Vibration Fatigue Using Uni-axial Vibration Test (단축가진 시험을 통한 진동내구 손상도 계산)

  • Kim, Chan-Jung;Bae, Chul-Yong;Lee, Bong-Hyun
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.16 no.5 s.110
    • /
    • pp.521-528
    • /
    • 2006
  • The vibration fatigue is suitable case of fatigue problem that system is exposed to the random or other irregular sources. Even some kinds of effort using power spectral density (PSD) and statistical concept was presented to cope with the intangible force signal, it is still lack of providing a reasonable solution when its exciting frequency is near or beyond of first eigenvalue. In this paper, energy approach method is presented to calculate a vibration induced fatigue damage in frequency domain. Since the corresponding damage become much larger than nominal case when the vibration is coupled with a mode shape of given structure, the new technique compensate the characteristics of structure with a measured frequency response function (FRF) between forcing acceleration and responding stress.

Quality Properties of Rice Cake Containing Bamboo Sprout Powder (죽순분말을 첨가한 절편(떡)의 특성)

  • Moon, Eun Woo;Park, Hun Jo;Na, Hwan Sik;Park, Jung Suk
    • Journal of the Korean Society of Food Culture
    • /
    • v.30 no.5
    • /
    • pp.650-655
    • /
    • 2015
  • Bamboo sprout powder was added to rice cake in an effort to improve the quality and functional properties of dough. The contents of crude protein and carbohydrates increased as the amount of bamboo sprout powder increased, whereas moisture contents decreased. According to increasing contents of bamboo sprout powder, total amino acid contents significantly increased. Hunter's L value decreased as contents of bamboo sprout powder increased, whereas sucrose contents increased. Addition of bamboo sprout powder to rice cake increased dietary fiber contents. Sensory scores of rice cake containing 90 g of bamboo sprout powder were the highest of all rice cakes tested. According to the results, adding bamboo sprout powder could improve the quality and sensory characteristics of rice cake.

Consumers's Distrust for Discounting Claims and Purchase Intention for Apparel Products (의류 제품의 할인판매에 대한 소비자의 불신과 구매의도에 관한 연구)

  • 오영아;정명선
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.21 no.8
    • /
    • pp.1307-1314
    • /
    • 1997
  • This study investigated the factors that influence consumers' distrust and consumers purchase intention for discounting, specifically discounting of clothes. Through literature, discounting rate, retailer type and brand reputation were identified as influencing factors and were tested. A 2$\times$2$\times$3 factorial design was used to test the effect of each factor on consumers' distrust and consumers' purchase intention for jean products. Retailer type was manipulated as high and low, brand reputation as well-known and less-known, and discount rates 10, 30 and 60%. An convenience sample of 165 female undergraduate students participated in the study. The data were analyzed using SPSS/PC+ The results showed that consumers did distrust discounting claims and consumers' distrust of the claims was greater for less-known brand. In addition, no significant effect of retailor type was found. Further effort is needed to generalize the result to different product categories.

  • PDF

A Study on the Optimal Mahalanobis Distance for Speech Recognition

  • Lee, Chang-Young
    • Speech Sciences
    • /
    • v.13 no.4
    • /
    • pp.177-186
    • /
    • 2006
  • In an effort to enhance the quality of feature vector classification and thereby reduce the recognition error rate of the speaker-independent speech recognition, we employ the Mahalanobis distance in the calculation of the similarity measure between feature vectors. It is assumed that the metric matrix of the Mahalanobis distance be diagonal for the sake of cost reduction in memory and time of calculation. We propose that the diagonal elements be given in terms of the variations of the feature vector components. Geometrically, this prescription tends to redistribute the set of data in the shape of a hypersphere in the feature vector space. The idea is applied to the speech recognition by hidden Markov model with fuzzy vector quantization. The result shows that the recognition is improved by an appropriate choice of the relevant adjustable parameter. The Viterbi score difference of the two winners in the recognition test shows that the general behavior is in accord with that of the recognition error rate.

  • PDF

Development of Prefabricated Joint for 66kV Cross Linked Polyethylene Cable. (66kV XLPE Cable용 조립형 접속함의 개발)

  • Oh, E.J.;Kim, K.Y.;Lee, J.Y.;Park, J.K.
    • Proceedings of the KIEE Conference
    • /
    • 1999.07e
    • /
    • pp.2123-2125
    • /
    • 1999
  • In recent the XLPE cable has been applied more widely because of its advantages, such as the low-cost and simple installation. For a prefabricated joint, its working time is short, its jointing procedures aγe simple, and its quality control is easy. Electrical performance targets of our developed 66kV cable accessories has been approved through the type test in accordance with IEC publication 840. This paper describes the developmental effort in terms of the design, structure and results of performance verification tests for 66kV XLPE cable system.

  • PDF

Experimental Study on Combustion and Emission Characteristics of Diesel Engine with Hydrogen Application (수소를 첨가한 디젤엔진의 연소 및 배기특성에 관한 실험적 연구)

  • Oh, Jungmo
    • Journal of ILASS-Korea
    • /
    • v.22 no.4
    • /
    • pp.203-209
    • /
    • 2017
  • The International maritime organization(IMO), in an effort to slow down the global warming, proposes reduction in ship's speed as a way to lower the rate emissions from ships. In addition, since ship's fuel cost have been increased, the shipping volumes, fuel-saving technology are being required urgently. Therefore, in this present study, a method of reducing the fuel cost that can improve the performance of the diesel engine was tried by introducing a predetermined amount (0.1~0.3% of the mass amount of fuel used) of hydrogen fuel additive. The experimental conditions of the test engine were 1500rpm and torque BMEP-10b ar. The engine performances (power output, fuel consumption rate, p-max, exhaust temperature) were compared before and after addition of hydrogen fuel additives. This experimental study confirmed reducing at least 2% fuel consumption and 2.19% NOx emission.

Application of artificial neural network for determination of wind induced pressures on gable roof

  • Kwatra, Naveen;Godbole, P.N.;Krishna, Prem
    • Wind and Structures
    • /
    • v.5 no.1
    • /
    • pp.1-14
    • /
    • 2002
  • Artificial Neural Networks (ANN) have the capability to develop functional relationships between input-output patterns obtained from any source. Thus ANN can be conveniently used to develop a generalised relationship from limited and sometimes inconsistent data, and can therefore also be applied to tackle the data obtained from wind tunnel tests on building models with large number of variables. In this paper ANN model has been developed for predicting wind induced pressures in various zones of a Gable Building from limited test data. The procedure is also extended to a case wherein interference effects on a gable roof building by a similar building are studied. It is found that the Artificial Neural Network modelling is seen to predict successfully, the pressure coefficients for any roof slope that has not been covered by the experimental study. It is seen that ANN modelling can lead to a reduction of the wind tunnel testing effort for interference studies to almost half.

Free Vibration Analysis of Perforated Plates Using Equivalent Elastic Properties

  • Park, Suhn;Jeong, Kyeong-Hoon;Kim, Tae-Wan;Kim, Kang-Soo;Park, Keun-Bae
    • Nuclear Engineering and Technology
    • /
    • v.30 no.5
    • /
    • pp.416-423
    • /
    • 1998
  • Many studies for the perforated plates have been done, especially on the subject of static behavior and stress distribution in the plate. Equivalent elastic properties are one of the successive concepts for this problem. However little effort was taken to get their dynamic characteristics. In this paper finite element modal analysis was performed for the perforated plates having square and triangular hole patterns. An attempt to use existing equivalent elastic properties into the modal analysis of the plate was carried out. To verify feasibility of the finite element models, modal test was also performed on one typical perforated plate. System parameters such as natural frequencies and mode shapes were extracted and compared with the analysis results.

  • PDF