External Indices Research Articles

Ground truth bias in external cluster validity indices

External cluster validity indices (CVIs) are used to quantify the quality of a clustering by comparing the similarity between the clustering and a ground truth partition. However, some external CVIs show a biased behavior when selecting the most similar clustering. Users may consequently be misguided by such results. Recognizing and understanding the bias behavior of CVIs is therefore crucial.It has been noticed that, some external CVIs exhibit a preferential bias towards a larger or smaller number of clusters which is monotonic (directly or inversely) in the number of clusters in candidate partitions. This type of bias is caused by the functional form of the CVI model. For example, the popular Rand Index (RI) exhibits a monotone increasing (NCinc) bias, while the Jaccard Index (JI) index suffers from a monotone decreasing (NCdec) bias. This type of bias has been previously recognized in the literature.In this work, we identify a new type of bias arising from the distribution of the ground truth (reference) partition against which candidate partitions are compared. We call this new type of bias ground truth (GT) bias. This type of bias occurs if a change in the reference partition causes a change in the bias status (e.g., NCinc, NCdec) of a CVI. For example, NCinc bias in the RI can be changed to NCdec bias by skewing the distribution of clusters in the ground truth partition. It is important for users to be aware of this new type of biased behavior, since it may affect the interpretations of CVI results.The objective of this article is to study the empirical and theoretical implications of GT bias. To the best of our knowledge, this is the first extensive study of such a property for external CVIs. Our computational experiments show that 5 of 26 pair-counting based CVIs studied in this paper, which are all functions of the RI, exhibit GT bias. Following the numerical examples, we provide a theoretical analysis of GT bias based on the relationship between the RI and quadratic entropy. Specifically, we prove that the quadratic entropy of the ground truth partition provides a computable test which predicts the NC bias status of the RI.

MLP, ANFIS, and GRNN based real-time coagulant dosage determination and accuracy comparison using full-scale data of a water treatment plant

Real-time determination of appropriate coagulant dosage under wide fluctuation of raw water quality in a water treatment plant (WTP) is a challenging task due to nonlinearity relation between coagulant dosage and raw water characteristics. In this research, three techniques, multilayer perceptron (MLP), adaptive neuro fuzzy inference system (ANFIS), and generalized regression neural network (GRNN), are applied to determine the coagulant dosage at Bansong drinking WTP. Each model is developed based on 8,760 historical data sets with hourly resolution for a whole year. Several statistical properties are determined to obtain the best-fit model from each method. The top performing models of each method are evaluated by external validation indices and absolute relative error according to nine turbidity zones. From the result, MLP and ANFIS models meet all conditions of validation indices, but GRNN cannot. The MLP shows the best result for high turbidity zones over 20 NTU as well as for overall performance. Meanwhile, ANFIS provides consistent results and better performance than MLP for low turbidity zones which have higher disorder of coagulant dosage data. The GRNN shows high accuracy for the highest turbidity zone which occurs during the rainy season. It is concluded that MLP, ANFIS, and GRNN can support operators effectively for real-time determination of coagulant dosage.

Market impact and structure dynamics of the Chinese stock market based on partial correlation analysis

Partial correlation analysis is employed to study the market impact on the Chinese stock market from both the native and external markets. Whereas the native market index is observed to have a great impact on the market correlations for both the Shanghai and Shenzhen stock markets, some external stock indices of the United States, European and Asian stock markets show a slight influence on the Chinese market. The individual stock can be affected by different economic sectors, but the dominant influence is from the sector the stock itself belongs to or closely related to, and the finance and insurance sector shows a weaker correlation with other economic sectors. Moreover, the market structure similarity exhibits a negative correlation with the price return in most time, and the structure similarity decays with the time interval.

СУЧАСНІ КОНЦЕПЦІЇ УПРАВЛІННЯ ЕФЕКТИВНІСТЮ ДІЯЛЬНОСТІ СІЛЬСЬКОГОСПОДАРСЬКИХ ПІДПРИЄМСТВ

В статті проаналізовано сучасні концепції управління ефективністю діяльності з метою їх адаптації до застосування в умовах сільськогосподарських підприємств України. В сучасних умовах розвитку усе більше поширення й застосування сучасних концепцій управління ефективністю діяльності сільськогосподарських підприємств з метою їх адаптації до застосування в умовах глобалізацієї світової економіки, підвищенням динамічності ринкового середовища і посиленням конкуренції в Україні. Відібрано і досліджено найбільш перспективні концепції, а саме концепція Business Performance Management (BPM) т аBalanced Scorecard (BSС), які б дозволили трансформувати поставлені стратегії та цілі у ряд дій, що б забезпечили їх досягнення; інтегрувати системний аналіз ефективності діяльності в управлінні. BPM спрямована на оптимізацію реалізації стратегії і складається з набору інтегрованих циклічних аналітичних процесів, підтримуваних відповідними технологіями і мають відношення як до фінансової, так і до операційної інформації та дозволяє сільськогосподарським підприємствам визначати, вимірювати і управляти ефективністю своєї діяльності, спрямованої на досягнення стратегічних цілей. BSС це система, яка переводить місію і загальну стратегію сільськогосподарських підприємств в систему чітко поставлених цілей і завдань, а також показників, що визначають ступінь досягнення даних установок. Вона забезпечує зворотний зв'язок між внутрішніми бізнессередовищем й зовнішніми показниками, необхідний для підвищення стратегічної ефективності й досягнення результатів. Концепції Business Performance Management та Balanced Scorecard є результатом еволюції як управлінської теорії, так і інформаційних технологій і вони ввібрали в себе як актуальні управлінські принципи, так і сучасні технології управління ефективністюсільськогосподарських підприємств.

A new index for clustering validation with overlapped clusters

External validation indexes allow similarities between two clustering solutions to be quantified. With classical external indexes, it is possible to quantify how similar two disjoint clustering solutions are, where each object can only belong to a single cluster. However, in practical applications, it is common for an object to have more than one label, thereby belonging to overlapped clusters; for example, subjects that belong to multiple communities in social networks. In this study, we propose a new index based on an intuitive probabilistic approach that is applicable to overlapped clusters. Given that recently there has been a remarkable increase in the analysis of data with naturally overlapped clusters, this new index allows to comparing clustering algorithms correctly. After presenting the new index, experiments with artificial and real datasets are shown and analyzed. Results over a real social network are also presented and discussed. The results indicate that the new index can correctly measure the similarity between two partitions of the dataset when there are different levels of overlap in the analyzed clusters.

Set Matching Measures for External Cluster Validity

Comparing two clustering results of a data set is a challenging task in cluster analysis. Many external validity measures have been proposed in the literature. A good measure should be invariant to the changes of data size, cluster size, and number of clusters. We give an overview of existing set matching indexes and analyze their properties. Set matching measures are based on matching clusters from two clusterings. We analyze the measures in three parts: 1) cluster similarity, 2) matching, and 3) overall measurement. Correction for chance is also investigated and we prove that normalized mutual information and variation of information are intrinsically corrected. We propose a new scheme of experiments based on synthetic data for evaluation of an external validity index. Accordingly, popular external indexes are evaluated and compared when applied to clusterings of different data size, cluster size, and number of clusters. The experiments show that set matching measures are clearly better than the other tested. Based on the analytical comparisons, we introduce a new index called Pair Sets Index (PSI).

Psychometrically Informed Approach to Integration of Multiple Informant Ratings in Adult ADHD in a Community-Recruited Sample.

Although Diagnostic and Statistical Manual of Mental Disorders-Fifth edition requires that attention-deficit/hyperactivity disorder (ADHD) symptoms are apparent across settings, assessed by multiple informants, there remains no standardized approach to integration of multiple sources in adult ADHD diagnosis. The goal of the study was to evaluate informant effects on adult ADHD symptom ratings. Participants were 406 adults, ages 18 to 37, and identified second reporters, recruited from the community, and completing a comprehensive diagnostic and cognitive assessment, including a clinician-administered diagnostic interview and self- and other-report questionnaires of ADHD symptoms. Structural equation modeling indicated good fit for a trifactor model of ADHD, including general ADHD, specific inattention and hyperactivity-impulsivity, and self- and other-perspective factors. Yet there were a number of symptoms on the specific hyperactive-impulsive and self-factors that exhibited nonsignificant loadings. Significant differential item functioning across self-ratings and informant ratings was also noted. The external validation indices of laboratory executive function and diagnostic team-rated impairment was significantly correlated with the specific inattentive factor. While executive function was marginally significantly correlated with the other perspective factor, impairment was associated with the self-perspective factor. Overall, inattentive symptoms may be more sensitive measures of adult ADHD, and other and self-ratings may provide different information in relation to external criteria.

Effects of building energy optimisation on the predictive accuracy of external temperature in forecasting models

The practice of using external temperature as a predictor of energy consumption in commercial buildings is well understood and it has been shown that this predictor is the most important when compared to other weather-based factors. In the literature, where a study has shown the external temperature not to be sufficiently accurate in forecasting energy usage by statistical methods, more predictors can be added to derive a more accurate forecasting model. The influence of the operating efficiency of the building on this accuracy has not been properly explained. This may be because of a lack of internal performance data for the building under review.This study has been developed to examine the effects of building operating efficiency on the forecasting accuracy of a statistical model by isolating external temperature as the sole predictor. The mechanism used to demonstrate the effects of the building's operating efficiency on the merit of using solely external temperature as a predictor is linear regression between external temperature and energy usage data.The study was carried out on two buildings of differing scale, occupational use and construction techniques. Using revised operational schemes involving more carefully controlled energy consumption and by monitoring local external temperatures, the relative accuracy of the various regression models is seen to be enhanced significantly following the efficiency programmes. The study has also facilitated an examination of the relative contributions to forecasting model accuracy resulting from energy efficiency actions taken in both buildings compared to the use of various external temperature indices.

A Novel Regression Based Clustering Technique for Wireless Sensor Networks

The objective of this paper is to develop a new adaptive iterative linear regression based clustering algorithm for wireless sensor network. According to this, the initial cluster is classified horizontally and vertically in parallel, each resulting in two sub-clusters. Of these two, the best is selected based on the proposed similarity index and with this selected cluster as reference, iteration continues until the convergence criterion `Delta' is met. The similarity index is designed based on the intra cluster similarity and inter cluster dissimilarity. Delta is the difference between the similarity index of the current iteration and the previous iteration. The proposal is implemented in MATLAB and simulations are carried out under different network scenarios. The cluster quality is evaluated through external and internal indices using the Cluster Validity Analysis Platform tool. The cluster obtained by the proposal is studied and its quality is compared with the well-established k-means and hierarchical clustering. The performance indices confirm the supremacy of the proposal.

Successful external validation of a model to predict other cause mortality in localized prostate cancer.

BackgroundAlthough life expectancy estimation is vital to decision making for localized prostate cancer, there are few, if any, valid and usable tools. Our goal was to create and validate a prediction model for other cause mortality in localized prostate cancer patients that could aid clinician’s initial treatment decisions at the point of care.MethodsWe combined an adjusted Social Security Administration table with a subset of comorbidities from a UK actuarial life expectancy model. Life tables were adjusted on the basis of survival data from a cohort of almost 10,000 radical prostatectomy patients treated at four major US academic institutions. Comorbidity-specific odds ratios were calculated and incorporated with baseline risk of mortality. We externally validated the model on 2898 patients from the Prostate Cancer Outcomes Study, which included men diagnosed with prostate cancer in six SEER cancer registries. These men had sufficient follow-up for our endpoints of 10- and 15-year mortality and also had self-reported comorbidity data.ResultsLife expectancy for prostate cancer patients were close to that of a typical US man who was 3 years younger. On external validation, 10- and 15-year concordance indexes were 0.724 and 0.726, respectively. Our model exhibited excellent calibration. Taking into account differences between how comorbidities are used in the model versus how they were recorded in the validation cohort, calibration would improve for most patients, but there would be overestimation of the risk of death in the oldest and sickest patients.ConclusionsWe successfully created and externally validated a new life expectancy prediction model that, while imperfect, has clear advantages to any alternative. We urge consideration of its use in counseling patients with localized prostate cancer.Electronic supplementary materialThe online version of this article (doi:10.1186/s12916-016-0572-z) contains supplementary material, which is available to authorized users.

Natural radioactivity levels in soils, rocks and water at a mining concession of Perseus gold mine and surrounding towns in Central Region of Ghana.

Levels of naturally occurring radioactive materials prior to processing of gold ore within and around the new eastern concession area of Perseus Mining (Ghana) Limited were carried out to ascertain the baseline radioactivity levels. The study was based on situ measurements of external gamma dose rate at 1 m above ground level as well as laboratory analysis by direct gamma spectrometry to quantify the radionuclides of interest namely; 238U, 232Th and 40K in soil, rock, ore samples and gross alpha/beta analysis in water samples. The average absorbed dose rate in air at 1 m above sampling point using a radiation survey metre was determined to be 0.08 ± 0.02 μGyh−1 with a corresponding average annual effective dose calculated to be 0.093 ± 0.028 mSv. The average activity concentrations of 238U, 232Th, and 40K in the soil, rock, and ore samples were 65.1 ± 2.2, 71.8 ± 2.2 and 1168.3 Bqkg−1 respectively resulting in an average annual effective dose of 0.91 ± 0.32 mSv. The average Radium equivalent activity value was 257.8 ± 62.4 Bqkg−1 in the range of 136.6–340.2 Bqkg−1. The average values of external and internal indices were 0.7 ± 0.2 and 0.9 ± 0.2 respectively. The average gross alpha and gross beta activity concentrations in the water samples were determined to be 0.0032 ± 0.0024 and 0.0338 ± 0.0083 Bql−1 respectively. The total annual effective dose from the pathways considered for this study (gamma ray from the soil, rock and ore samples as well as doses determined from the gross alpha/beta activity concentration in water samples) was calculated to be 0.918 mSv. The results obtained in this study shows that the radiation levels are within the natural background radiation levels found in literature and compare well with similar studies for other countries and the total annual effective dose is below the ICRP recommended level of 1 mSv for public exposure control.

Analysis of flux reduction behaviors of PRO hollow fiber membranes: Experiments, mechanisms, and implications

Pressure retarded osmosis (PRO) is a promising technology to harvest renewable osmotic energy using a semipermeable membrane. However, a significant flux reduction has been always observed that severely shrinks the harvestable power to a level only marginally higher or even lower than the economically feasible value. This work focuses on the elucidation of various underlying mechanisms responsible for the flux reduction. First, both inner-selective and outer-selective thin film composite (TFC) hollow fiber membranes are employed to examine how the fundamental internal factors (such as the surface salinity of the selective layer at the feed side (CF,m) and its components) interact with one another under the fixed bulk salinity gradient, resulting in various behaviors of external performance indexes such as water flux, reverse salt flux, and power density. Then, the research is extended to investigate the effects of the growing bulk feed salinity due to the accumulated reverse salt flux along PRO modules. Finally, the insights obtained from the prior two stationary conditions are combined with the advanced nucleation theory to elucidate the dynamic scaling process by visualizing how the multiple fundamental factors (such as local supersaturation, nucleation rate and nuclei size) evolve and interplay with one another in various membrane regimes during the whole scaling process. To our best knowledge, it is the first time that the advanced nucleation theory is applied to study the PRO scaling kinetics in order to provide subtle and clear pictures of the events occurring inside the membrane. This study may provide useful insights to design more suitable TFC hollow fiber membranes and to operate them with enhanced water flux so that the PRO process may become more promising in the near future.

Cloud information system «Redactor.Online» for the create of periodic scientific-educational editions

The article presents the approaches to the creation of cloud information system for automation of business processes related to the preparation and publication of periodic scientific and educational publications (publishing). The aim of the research is the development of concepts, models, patterns, architecture of such a system, the choice of software implementation. The urgency of development based on the results of a study of existing and used in practice technologies for creating electronic versions of scientific journals and other types of scientific and educational resources. It is expected that the use of cloud-based systems will reduce the time and cost of publishing houses, as well as improve the quality of published material (for example, through the use of their interactive and multimedia elements, add comments and assessment opportunities articles and so forth.). Description is given on an example of cloud Redactor.Online system developed by small innovative enterprises of Petrozavodsk State University «Internet-business-system». As a means of implementation chosen freelydistributed products, such as PostgreSQL, PHP, Yii Framework. Logically, the cloud structure of the system is a set of components, based on common data sources and interacting with each other. The main components of the system are the basic (general) part of promo-site system, editorial offices of periodicals created in the system, media sites, mobile applications editions, complex control system as a whole. The central element of the system architecture is the editorial offices. It provides a set of features related to the preparation for release and publication of the magazine, including the management of the lifecycle of the article (step preparation of the article the author, its review, proofreading, typesetting, translation, publication, and export to external citation indexes). Available functionality of this component is determined by the role assigned to the user - the editorial staff or author. Allocate such basic roles (offices), as a author office, reviewer office, corrector office, translator office, designer office, the editor’s office. A single user can have multiple roles, and perform various functions related to the preparation of articles for publication (eg, translate, and adjust the paper). You can also specify the settings in the publication, and the role of the steps which are required and which are not needed. Using Redactor.Online system built on the basis described in this paper approaches will significantly reduce the time and costs for the implementation of business processes related to organizational activities of publication and for potential users of the system, including educational and research institutions, engaged in release electronic journals. system interfaces and subsystems allow the Internet fast enough to create the appropriate publication site and configure its design, content, access parameters, modes of operation, in accordance with the requirements of the creator.

Adjusting for chance clustering comparison measures

Adjusted for chance measures are widely used to compare partitions/clusterings of the same data set. In particular, the Adjusted Rand Index (ARI) based on pair-counting, and the Adjusted Mutual Information (AMI) based on Shannon information theory are very popular in the clustering community. Nonetheless it is an open problem as to what are the best application scenarios for each measure and guidelines in the literature for their usage are sparse, with the result that users often resort to using both. Generalized Information Theoretic (IT) measures based on the Tsallis entropy have been shown to link pair-counting and Shannon IT measures. In this paper, we aim to bridge the gap between adjustment of measures based on pair-counting and measures based on information theory. We solve the key technical challenge of analytically computing the expected value and variance of generalized IT measures. This allows us to propose adjustments of generalized IT measures, which reduce to well known adjusted clustering comparison measures as special cases. Using the theory of generalized IT measures, we are able to propose the following guidelines for using ARI and AMI as external validation indices: ARI should be used when the reference clustering has large equal sized clusters; AMI should be used when the reference clustering is unbalanced and there exist small clusters.

A PROPOSED ALGORITHM FOR DETERMINING THE OPTIMAL NUMBER OF CLUSTERS

Data clustering is a data exploration technique that allows objects with similar characteristics to be grouped together in order to facilitate their further processing. The K-means algorithm is a popular data-clustering algorithm. However, one of its drawbacks is the requirement for the number of clusters, K, to be specified before the algorithm is applied. This paper first reviews existing methods for selecting the number of clusters for the algorithm. Factors that affect this selection are then discussed and an improvement of the existing k-means algorithm to assist the selection is proposed. The paper concludes with an analysis of the results of using cluster validation referring to some measures that are classified as internal and external indexes to determine the optimal number of clusters for the K-means algorithm. There are applied some stopping criterion referring to those indexes for evaluating a clustering against a gold standart.

Knee Arthrodesis in Persistently Infected Total Knee Arthroplasty.

The reported incidence of infection in total knee arthroplasty (TKA) varies from 0.5 to 15%. The most common indication for knee arthrodesis is persistent infection after repeated staged knee replacement. The purpose of this study is to investigate the success of fusion with monoplanar fixators and eradication rates of infection, and to evaluate the satisfaction of patients who underwent a last-resort TKA due to infection.This is a retrospective review of infected knee arthroplasties that were treated with knee arthrodesis using unilateral external fixators at a single institution from 1999 through 2012. The patients' charts were analyzed for demographics, types of external fixators used, infection parameters, external fixator indexes, complications, positions of fusion, and leg length discrepancies (LLDs). Patients were called back to return for additional follow-up. A self-administered general health status questionnaire (SF-36) was assessed to evaluate life quality.There were 14 women and 3 men with an average age of 67 ± 16.6 years. Antibiotic-loaded acrylic cements were used as a spacer for an average of 3.4 ± 1.2 months in all patients. Monoplanar type of external fixator was used in all 17 patients. Fusions were achieved in all but one patient. The mean duration of fusion was 6.8 ± 2.2 months and external fixator duration was 7.6 ± 2.4 months. Average LLD was 2.9 ± 1.7 cm. The mean coronal alignment of fusion was 6.8 degrees (± 3.3 degrees, range 4-15 degrees) valgus and mean flexion was 11.3 degrees (± 6.5 degrees, range 3-30 degrees). Compared with the healthy controls, the SF-36 scores were significantly lower in patients with knee arthrodesis (physical component score [PCS]-arthrodesis: 39.3 vs. PCS- healthy controls: 47.9, p < 0.05; mental component score [MCS]-arthrodesis: 38.6 versus MCS-healthy controls: 47.7, p < 0.05).Use of monoplanar fixators for arthrodesis in infected TKA can achieve high fusion rates with the control of infection. If fusion can be achieved, the patient satisfaction is low with acceptable pain relief and functionality. We observed that monoplanar external fixators increased patients' comfort levels compared with circular external fixators. Further studies are needed to compare different arthrodesis modalities in patients with infected TKA.

Currency crisis and external fragility: a Minskyan interpretation applied to the Brazilian economy between 1999 and 2013

Abstract: This work has two goals. The first one is to develop an interpretation for open economies founded on Minsky’s financial fragility hypothesis about the process of a currency crisis and its determinants. The deterioration of an economy’s external financial structure is identified as the reason for the increase of its crisis susceptibility. With this approach, we create external fragility indexes intending to measure an economy’s crisis susceptibility. Our second objective is to evaluate the Brazilian external fragility between 1999 and 2013using the index and the interpretation previously developed. The results suggest that Brazilian’s external fragility suffered a gradual and significant decrease and tends to follow stable trend in the coming years.

Assessment of natural radioactivity in fertilizers and phosphate ores in Egypt

Radionuclide concentrations of uranium (238U), thorium (232Th) and potassium (40K) maintained in 10 phosphate ore and 5 fertilizer samples were measured using a high-purity germanium detector. The concentrations of these radionuclides in the phosphate ore samples were relatively high for 226Ra at 871.37±91.90Bqkg−1 and relatively low for 232Th and 40K at 19.21±2.42Bqkg−1 and 176.06±17.66Bqkg−1, respectively. The concentrations of these radionuclides were low in the fertilizer samples. The radiological hazards of the radium equivalent activity (Raeq), external (Hex) and internal (Hin) indices and annual effective dose due to the presence of these radionuclides in the investigated samples were calculated. The released radon from the selected samples was measured using the Alpha Guard radon monitor. Subsequently, the radon emanation coefficient and its exhalation rate were calculated.

Risk evaluation of land subsidence and its application to metro safety operation in Shanghai

Abstract. Based on sufficiently investigating characteristics and risk connotation of land subsidence, a risk evaluation index system for land subsidence disaster is established, which is combined with the sensitivity feature of the hazard bearing body to land subsidence. An appropriate evaluation method system is established by using an improved fuzzy analytic hierarchy process method. So risk evaluation is developed for providing theoretical basis and technical support for the regional management of land subsidence prevention and control. On this basis, as a case of Shanghai metro, firstly, the paper studies the identifying risk sources of the metro. According to metro linear characteristics, external indexes of representing subsidence risk are obtained. Studying the subsidence risk of the metro, relevant achievement has provided the technical basis for daily main monitoring, early warning and work arrangement.

Assessment of Natural Radioactivity Levels and Potential Radiological Risks of Common Building Materials Used in Bangladeshi Dwellings.

The concentrations of primordial radionuclides (226Ra, 232Th and 40K) in commonly used building materials (brick, cement and sand), the raw materials of cement and the by-products of coal-fired power plants (fly ash) collected from various manufacturers and suppliers in Bangladesh were determined via gamma-ray spectrometry using an HPGe detector. The results showed that the mean concentrations of 226Ra, 232Th and 40K in all studied samples slightly exceeded the typical world average values of 50 Bq kg−1, 50 Bq kg−1 and 500 Bq kg−1, respectively. The activity concentrations (especially 226Ra) of fly-ash-containing cement in this study were found to be higher than those of fly-ash-free cement. To evaluate the potential radiological risk to individuals associated with these building materials, various radiological hazard indicators were calculated. The radium equivalent activity values for all samples were found to be lower than the recommended limit for building materials of 370 Bq kg-1, with the exception of the fly ash. For most samples, the values of the alpha index and the radiological hazard (external and internal) indices were found to be within the safe limit of 1. The mean indoor absorbed dose rate was observed to be higher than the population-weighted world average of 84 nGy h–1, and the corresponding annual effective dose for most samples fell below the recommended upper dose limit of 1 mSv y–1. For all investigated materials, the values of the gamma index were found to be greater than 0.5 but less than 1, indicating that the gamma dose contribution from the studied building materials exceeds the exemption dose criterion of 0.3 mSv y-1 but complies with the upper dose principle of 1 mSv y−1.