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101.
Multirelational k-Anonymity 总被引:1,自引:0,他引:1
Nergiz Mehmet Ercan Clifton Christopher Nergiz Ahmet Erhan 《Knowledge and Data Engineering, IEEE Transactions on》2009,21(8):1104-1117
k-Anonymity protects privacy by ensuring that data cannot be linked to a single individual. In a k-anonymous data set, any identifying information occurs in at least k tuples. Much research has been done to modify a single-table data set to satisfy anonymity constraints. This paper extends the definitions of k-anonymity to multiple relations and shows that previously proposed methodologies either fail to protect privacy or overly reduce the utility of the data in a multiple relation setting. We also propose two new clustering algorithms to achieve multirelational anonymity. Experiments show the effectiveness of the approach in terms of utility and efficiency. 相似文献
102.
Seismic base isolation using low-cost Scrap Tire Pads (STP) 总被引:1,自引:0,他引:1
This paper focuses on the experimental studies conducted on the development of no-cost seismic base isolation pads using scrap
automobile tire pads (STP). The mechanical and dynamic properties of STP specimens made from different tire brands, with different
number of layers, and orientations are evaluated experimentally. The tests are conducted using (a) axial compression tests,
(b) lumped mass small displacement free vibration, and (c) large displacement (inclined plate and reverse-cyclic) static shear
tests. The results of these STP tests are compared among themselves and against a commercially available laminated rubber
bearing specimen. A general relationship has been proposed which formulates the stiffness differences between the two principal
directions of rectangular pads. The paper includes three hypothetical design applications for the use of STPs.
STPs are prepared by placing 18 cm × 20 cm cut tread sections layers of car tires on top each other. Larger size STPs can
also be formed by placing longer strips of tread sections (integer multiples of tread width) side by side in alternating direction
layers or using a woven structure. Test results have shown that the friction between tire layers is sufficient to keep layers
intact. Although STP application cannot eliminate foundation-basement structural requirements, it presents advantages such
as low-technology no-cost pad, weight reduction, ease of handling, simple shear stiffness adjustment by changing the number
of layers, and environmental benefits by recycling scrap tires. 相似文献
103.
The aims of the present study were to determine biochemical properties of honey samples and to discriminate pure and adulterated honey produced by the standard bee feeding method (control honey), the shaking method (pure blossom honey), and overfeeding (100 kg/colony syrup) with sucrose syrup (adulterated honey). The biochemical properties evaluated were moisture, ash, acidity, hydroxymethylfurfural (HMF), specific sugars (i.e. fructose, glucose, fructose–glucose, sucrose, and maltose), diastase activity, δ13C value (honey), δ13C value (protein), electrical conductivity, potassium, vitamin C, and proline. Fifteen honey samples were analyzed by discriminant analysis stepwise method. Proline, electrical conductivity and sucrose were found as discriminative characters of samples. Based on these three properties 100% of original group cases (samples) correctly classified in their real group. We found that the honey produced by feeding with 100 kg sucrose syrup per colony contained the sucrose as low as pure blossom honey. Therefore, the sugar (sucrose, fructose and glucose) content of honey cannot be used to distinguish between adulterated (sucrose syrup) and pure blossom honey. 相似文献
104.
Cold season heating energy requirements in buildings can be estimated with the degree-hours method based on human comfort levels and available meteorological temperature records for a given area. Such estimations are especially significant for cities where fossil fuel consumption must be eliminated in favor of clean energy alternatives to reduce air pollution. This paper considers the city of Istanbul in Turkey and presents a detailed account for practical energy requirements and fuel consumption calculations. 相似文献
105.
Gross-α and gross-β, activities of eight well and five tap water samples taken in
stanbul were determined. Ra226, Rn222, Pb214, Bi214, K40, Cs137 activity concentrations in four lake, four sea water, one snow and one rain water samples were also analyzed in order to determine their radioactivity. The results obtained showed that, in general, natural activities in drinking water samples did not exceed WHO and ITS guidelines. In sea and lake water, four samples were over WHO and TSI guidelines. Concentrations ranging from 0.007 to 0.04 Bq l−1 and from 0.02 to 0.1 Bq l−1 were observed for drinking water and the gross-α and gross-β activities, respectively. For all samples the gross-β activities were higher than the corresponding gross-α activities. In order to evaluate the annual effective dose equilavent of ingestion of these waters, a conservative dosimetric calculation was carried out using dose conversion factor suggested by the ICRP. An average annual effective dose equivalent of 0.84 μSv y−1 for Ra226 was calculated. 相似文献
106.
Nurgaliyev Madiyar Saymbetov Ahmet Yashchyshyn Yevhen Kuttybay Nurzhigit Tukymbekov Didar 《Wireless Networks》2020,26(5):3507-3520
Wireless Networks - This paper shows a method for predicting the lifetime of a wireless sensor network based on the LoRa Ra-01 wireless modules. To develop a prediction model of the energy... 相似文献
107.
Seasonal storage of solar energy to supply the heat requirement of buildings in Edirne (41°39′54″N) has been examined experimentally. Solar energy has been stored in a cylindrical underground storage unit. Measurement values have been recorded per hour by means of a computerized recorder between July 2005 and May 2006. Monthly average temperature values of the heat storage unit and the surrounding ground have been calculated through the measurement results. The transient heat transfer which takes place between the heat storage unit and the surrounding ground has been calculated by means of the QuickField finite-element analysis program. It has been determined that the most significant deviations between the theoretical and the experimental temperature values turn out to be in question during the heating period. The annual solar fraction of the solar energy heating system has been determined as 53% for space heating and 85% for domestic water heating. 相似文献
108.
In this paper we undertake an experimental and numerical study on heat and mass transfer analysis during drying of kiwi fruits. In the experimental part, the effects of various drying conditions in terms of air velocity, temperature and relative humidity on drying characteristics of kiwi fruits are investigated. In the numerical part, the external flow and temperature fields are studied using a commercial CFD package. From these fields, the local distributions of the surface convective heat transfer coefficients for the fruits are determined to predict the local convective mass transfer coefficients through the analogy between the thermal and concentration boundary layers (known as the Chilton–Colburn analogy). In addition, the time-dependent temperature and moisture distributions for different cases are obtained using the code developed to investigate heat and mass transfer aspects inside the fruits. Numerical results are then compared with experimental data and a considerably high agreement is obtained. 相似文献
109.
Ahmet Gunes Yardimci Celal Karpuz 《Bulletin of Engineering Geology and the Environment》2018,77(1):253-264
Rock slope failure modes are either driven by structurally controlled mechanisms (planar, wedge, or toppling failure) or lean upon the highly jointed or weak rock mass (circular failure). Developing practical tools for preliminary slope design is a popular topic among geotechnical society. This study proposes a practical methodology to predict a safe overall slope angle for weak rock slopes of lignite mines. Rock mass rating (RMR) and slope mass rating (SMR) classification systems can be remarkably misleading for weak rocks. Fuzzy modification was proven to improve rock and slope quality predictions. In addition, structurally controlled failures can be estimated more precisely. Later, a popular slope performance chart of Bieniawski that is based on RMR was modified by the fuzzy approach, and the computer models of a weak rock mass failure in a Turkish lignite mine are presented. The modified methodology was proven to be better suited to the weak rock conditions. 相似文献
110.
The accumulation of La,Ce and Y by Lemna minor and Lemna gibba in the Keban gallery water,Elazig Turkey 下载免费PDF全文
This study investigated the phytoremediation ability of Lemna minor and Lemna gibba to accumulate lanthanum, cerium and yttrium from gallery water polluted by metals. L. minor and L. gibba were settled in the mining water and adapted to separate reactors. During the experiment, the water and plant samples were daily taken and the temperature, electric conductivity and pH of the water were daily measured in situ. These plants were firstly washed, dried in and then ashed at 300°C for 24 h in an oven. Both water and ashed plant samples were measured by ICP‐MS to detect the concentrations of lanthanum (La), cerium (Ce) and yttrium (Y). Although these elements are at low concentrations in gallery water, they were accumulated at the highest levels in L. gibba and in L. minor. This study showed that both plants have high ability to remove lanthanum, cerium and yttrium in gallery water polluted by different elements. 相似文献