Comparing clustering solutions: the use of adjusted paired indices

In the present paper we compare clustering solutions using indices of paired agreement. We propose a new method - IADJUST - to correct indices of paired agreement, excluding agreement by chance. This new method overcomes previous limitations known in the literature as it permits the correction of any index. We illustrate its use in external clustering validation, to measure the accordance between clusters and an a priori known structure. The adjusted indices are intended to provide a realistic measure of clustering performance that excludes agreement by chance with ground truth. We use simulated data sets, under a range of scenarios - considering diverse numbers of clusters, clusters overlaps and balances - to discuss the pertinence and the precision of our proposal. Precision is established based on comparisons with the analytical approach for correction specific indices that can be corrected in this way are used for this purpose. The pertinence of the proposed correction is discussed when making a detailed comparison between the performance of two classical clustering approaches, namely Expectation-Maximization (EM) and K-Means (KM) algorithms. Eight indices of paired agreement are studied and new corrected indices are obtained.

40 K Neon liquid energy storage unit

Cryocoolers have been progressively replacing the use of the stored cryogens in cryogenic chains used for detector cooling, thanks to their higher and higher reliability. However, the mechanical vibrations, the electromagnetic interferences and the temperature fluctuations inherent to their functioning could reduce the sensor’s sensitivity. In order to minimize this problem, compact thermal energy storage units (ESU) are studied, devices able to store thermal energy without significant temperature increase. These devices can be used as a temporary cold source making it possible to turn the cryocooler OFF providing a proper environment for the sensor. A heat switch is responsible for the thermal decoupling of the ESU from the cryocooler’s temperature that increases when turned OFF. In this work, several prototypes working around 40 K were designed, built and characterized. They consist in a low temperature cell that contains the liquid neon connected to an expansion volume at room temperature for gas storage during the liquid evaporation phase. To turn this system insensitive to the gravity direction, the liquid is retained in the low temperature cell by capillary effect in a porous material. Thanks to pressure regulation of the liquid neon bath, 900 J were stored at 40K. The higher latent heat of the liquid and the inexistence of triple point transitions at 40 K turn the pressure control during the evaporation a versatile and compact alternative to an ESU working at the triple point transitions. A quite compact second prototype ESU directly connected to the cryocooler cold finger was tested as a temperature stabilizer. This device was able to stabilize the cryocooler temperature ((≈ 40K ±1 K) despite sudden heat bursts corresponding to twice the cooling power of the cryocooler. This thesis describes the construction of these devices as well as the tests performed. It is also shown that the thermal model developed to predict the thermal behaviour of these devices, implemented as a software,describes quite well the experimental results. Solutions to improve these devices are also proposed.

40 K neon liquid energy storage unit

Cryocoolers have been progressively replacing the use of the stored cryogens in cryogenic chains used for detector cooling, thanks to their higher and higher reliability. However, the mechanical vibrations, the electromagnetic interferences and the temperature fluctuations inherent to their functioning could reduce the sensor’s sensitivity. In order to minimize this problem, compact thermal energy storage units (ESU) are studied, devices able to store thermal energy without significant temperature increase. These devices can be used as a temporary cold source making it possible to turn the cryocooler OFF providing a proper environment for the sensor. A heat switch is responsible for the thermal decoupling of the ESU from the cryocooler’s temperature that increases when turned OFF. In this work, several prototypes working around 40 K were designed, built and characterized. They consist in a low temperature cell that contains the liquid neon connected to an expansion volume at room temperature for gas storage during the liquid evaporation phase. To turn this system insensitive to the gravity direction, the liquid is retained in the low temperature cell by capillary effect in a porous material. Thanks to pressure regulation of the liquid neon bath, 900 J were stored at 40K. The higher latent heat of the liquid and the inexistence of triple point transitions at 40 K turn the pressure control during the evaporation a versatile and compact alternative to an ESU working at the triple point transitions. A quite compact second prototype ESU directly connected to the cryocooler cold finger was tested as a temperature stabilizer. This device was able to stabilize the cryocooler temperature ((≈ 40K ±1 K) despite sudden heat bursts corresponding to twice the cooling power of the cryocooler. This thesis describes the construction of these devices as well as the tests performed. It is also shown that the thermal model developed to predict the thermal behaviour of these devices,implemented as a software, describes quite well the experimental results. Solutions to improve these devices are also proposed.

Efeitos de diferentes níveis de N, P e K sôbre cacaueiros jovens (Theorema cacao L.) em solução nutritiva

Cocoa seedlings were grown in nutrient solution in order to find out the effects of the levels of N, P, K in the substrate on growth, symptoms and chemical composition of the leaves. A 3x3x3 factorial design was used. The following conclusions can be drawn. 5.1. Among the three elements under study, only nitrogen had a positive, significant effect on growth as measured by height and dry weight. 5.2. The level of a given elements in the leaves did increase when its level in the nutrient solution was raised. On the other hand the N content was positively affected by the concentration of P in the substrate. 5.3. A decrease in the N/P and K/P rations in the leaves was observed when the nutrient solutions had, res-respectively, absence of K and N and high level both of K and N. The N/K ratio increased with the level of P in the substrate. 5.4 A highly significant positive correlation was found between N content in the leaves and dry weight. This was not the case however, insofar P and K are considered - no correlation whatsoever was observed.

Effect of day time on foliar spraying of several levels of nitrogen fertilizer, NPKS solutions and its components, on common bean leaves

An experiment was carried out in order to determine the effect of day time of foliar spraying of several levels of nitrogen fertilizers, N-P-K-S station, and its components on common bean leaves. Results, based on the visual observations, indicated the maximum levels of each fertilizer that did not cause injuries and showed that the foliar spraying early in the morning is the best day time.

[Archives de la Parole]. , La parabole de l'enfant prodigue : récit (dravidien, malayālam, province de Madras) / [Sir George Grierson], éd. ; Linguistic survey of India ; [C.K. Gopalamenon], voix

[Traditions. Asie. Inde. Province de Madras [i.e. Chennai]. État du Kérala. Région du Malabar]

[Archives de la Parole]. , Nadar dadā and Dalang dadā : two songs in Kōrwā from Sarguja (C.P.) / [Sir George Grierson], éd. ; Linguistic survey of India ; [Nathu Kōrwā], voix

[Traditions. Asie. Inde. Chhattisgarh. Surguja]

[Archives de la Parole]. , [Chant populaire en khāndeśī] : indo-aryen / [Sir George Grierson], éd. ; Linguistic survey of India ; [K.S. Vani], voix

[Traditions. Asie. Inde. État du Maharashtra. Dhule]

[Archives de la Parole]. , Sīkā me tānge : a song in Chhattīsgaṛhī Hindī from Raipur (C.P.) [i.e. Central Provinces] / [Sir George Grierson], éd. ; Linguistic survey of India ; [Brijlal Raut], voix

[Traditions. Asie. Inde. Chhattisgarh. Raipur]

[Archives de la Parole]. , [The silly weaver girl] : récit (dravidien, malayālam, province de Madras) / [Sir George Grierson], éd. ; Linguistic survey of India ; [K.K. Achyutan], voix

[Traditions. Asie. Inde. Province de Madras [i.e. Chennai]. État du Kérala. Kochi]

Fantaisie en ut mineur, K 475 / Mozart, comp. ; revue et annotée par Lazare-Lévy ; Lazare-Lévy, p

Titre uniforme : [Fantaisies. Piano. KV 475. Do mineur]

[Archives de la Parole]. , [The king and the margosa seed] : récit en dravidien, telugu, Province de Madras / [Sir George Grierson], éd. ; Linguistic survey of India ; [K. Divakara Rao], voix

[Traditions. Asie. Inde. Présidence de Madras [i.e. Chennai]. Ceded Districts]

[Archives de la Parole]. , [The silly weaver girl] : récit (dravidien, Malayalam, Province de Madras) / [Sir George Grierson], éd. ; Linguistic survey of India ; [C.K. Gopalamenon], voix

[Traditions. Asie. Inde. Présidence de Madras [i.e. Chennai]. Etat du Kerala. Région du Malabar]

[Archives de la Parole]. , La parabole de l'enfant prodigue : dravidien, malayālam, province de Madras / [Sir George Grierson], éd. ; Linguistic survey of India ; [K.K. Achyutan], voix

[Traditions. Asie. Inde. Province de Madras [i.e. Chennai]. État du Kérala. Kochi]

[Archives de la Parole]. , [Song addressed to a maiden] : [in Amindivi MalayāỊam] / [Sir George Grierson], éd. ; Linguistic survey of India ; [Kilaveliyan Muhammad Kōya], voix

[Traditions. Asie. Inde. Province de Madras [i.e. Chennai]. État de Karnataka. Région du Kanara]