Multi-Projection Segmentation on Dental Cone Beam Computed Tomography Images Using Level Set Method

Segmentation of dental Cone-beam computed tomography (CBCT) images based on Boundary Tracking has been widely used in recent decades. Generally, the process only uses axial projection data of CBCT where the slices image that representing the tip of the tooth object have decreased in contrast which impact to difficult to distinguish with background or other elements. In this paper we propose the multi-projection segmentation method by combining the level set segmentation result on three projections to detect the tooth object more optimally. Multiprojection is performed by decomposing CBCT data which produces three projections called axial, sagittal and coronal projections. Then, the segmentation based on the set level method is implemented on the slices image in the three projections. The results of the three projections are combined to get the final result of this method. This proposed method obtains evaluation results of accuracy, sensitivity, specificity with values of 97.18%, 88.62%, and 97.61%, respectively.

Penerapan Quality Control pada Souvenir Logo PNP dengan Metode Box Plot dan Six Sigma

The quality of a product determines the level of market demand. This paper discusses the determination of the quality level of plastic molding with the sigma level method which uses the Box Plot to determine the desired quality limit. The purpose of this research is to determine the level of quality of product using statistics. The object of this research is to determine the weight variation of the souvenir of PNP logo with a weight indicator. The experiment were carried out on 200 samples taken at random.Then each sample is numbered from 1 to 200. Each sample is weighed carefully. The results obtained were processed using a box plot to obtain the numbered of rejected samples from 200 samples that were weighed. The result of data processing obtained 19 reject products from 200 products tested. From this data there are 9,5% of products that do not meet the desired specifications. Furthermore, the sigma level is determined from the results of data processing using a box plot. DPMO of 9.5% is 95000 Defects per Milion Opportunities. The result of determining the sigma level is 2.8 Sigma.

A Study on Fault Tolerance Technology of Flight Control Computer for Unmanned Aerial Vehicle

According to the reliability requirement of the Flight Control Computer for Unmanned Aerial Vehicle (UAV), a design scheme is proposed to ensure its reliability by using tri-redundancy technology. Further, by selecting appropriate redundant mode and the architecture model of the triple redundant flight control computer is established in this paper. The multi-channel security level method can give full play to the error tolerance ability of the system and improve the fault tolerance performance of the aircraft. After an extensive analysis and study of the structure of each module, the hardware circuit and software flow chart of the key technologies, such as redundancy strategy and synchronization method are suggested. A channel selection method based on channel security level is proposed. Combined with the comparison technology between channels, the selection of the optimal safe channel is realized.

Non-polynomial Cubic Spline Method for the Solution of Second-order Linear Hyperbolic Equation

Second-order linear hyperbolic equations are solved by using a new three level method based on nonpolynomial spline in the space direction and Taylor expansion in the time direction. Numerical results reveal that three level method based on non-polynomial spline is implemented and effective

Information-Theoretic Channel for Multi-exposure Image Fusion

Multi-exposure image fusion has emerged as an increasingly important and interesting research topic in information fusion. It aims at producing an image with high quality by fusing a set of differently exposed images. In this article, we present a pixel-level method for multi-exposure image fusion based on an information-theoretic approach. In our scheme, an information channel between two source images is used to compute the Rényi entropy associated with each pixel in one image with respect to the other image and hence to produce the weight maps for the source images. Since direct weight-averaging of the source images introduce unpleasing artifacts, we employ Laplacian multi-scale fusion. Based on this pyramid scheme, images at every scale are fused by weight maps, and a final fused image is inversely reconstructed. Multi-exposure image fusion with the proposed method is easy to construct and implement and can deliver, in less than a second for a set of three input images of size 512$\times $340, competitive and compelling results versus state-of-art methods through visual comparison and objective evaluation.

Measuring the Total Logistics Costs at the Macro Level: A Study of Indonesia

Background: Efforts made to calculate the logistics costs in Indonesia, at the macro level, are facing various problems, due to the fact that there have been no national agreements—to any models employed—to calculate those costs. Moreover, limited data and information due to the lack of use of such integrated information technology to reduce the information asymmetry on the logistics processes and activities have created some additional problems. Objective: This study is aimed at reviewing the measurement model, of the logistics costs used in Indonesia, at the macro level. Method: It provides a potential measurement approach proposed by several previous studies as an alternative option that may help develop the existing models by elaborating on their limitations. Results: The results of this study emphasize the recognition of the components of the logistics costs and the formulation of a more accurate, transparent, and comprehensive measurement framework to improve the standard used to assess the logistics costs. Conclusion: Thus, the calculation output of the logistics costs is expected to be able to provide stakeholders with reliable information to develop an efficient logistics system. Furthermore, logistics costs will be more controllable, allowing Indonesia to achieve such comparative advantages.

Analysis situation of urban green space framework in Tehran

Introduction. In recent years, the development of cities and the increase in urban population has upset the balance of urban ecology in Iran. The destruction of agricultural fields and natural areas, as well as changes in the function of urban green spaces have caused environmental problems. Therefore, the main purpose of this study is to investigate the distribution of green space in Tehran with an environmental sustainability approach. Materials and methods. The research method is applied in terms of purpose and descriptive-analytical in terms of method. Basic information has been obtained through library studies and Tehran Municipality and using GIS, mathematical and statistical methods such as entropy coefficient, Concentration level method, Lorenz curve, Location quotient (L.Q) method, Distribution quotient (D.Q) method distribution of Tehran green space function were analyzed. Results. The results show the unbalanced and inappropriate spatial distribution of green space and the critical environmental situation in the 22 districts of Tehran. According to the entropy coefficient model, district 18 is the most unbalanced distribution and in contrast, district 2 has the most balanced distribution. The results of the concentration level method based on the value of C obtained for each of the districts showed that districts 4 and 1 with the level of 2.141 and 2.103 have the highest concentration level and other districts have much less concentration level than these districts. The Lorenz curve also indicates that the distribution of urban green spaces in 22 districts of Tehran is different from the uniform distribution, and in some districts, it is higher than the uniform distribution and, in some districts, it is lower, which indicates an unbalanced distribution between the districts. Location quotient (L.Q) method and distribution quotient (D.Q) method also showed that the concentration and density of green space use in different districts of Tehran was inappropriate and unbalanced. Conclusions. This research show that according to the 8 million population in Tehran, its per capita green space is 16.27 square meters and its distribution is unbalanced in 22 districts. Also districts 1 and 22 with a per capita of 33.85 and 58.67 square meters and having 204 and 77 green spaces in the suitable situation and districts 10 and 11 districts with a per capita of 2.58 and 4.96 and having 51 and 30 green spaces are in the unsuitable situation. And according to the statistical methods used, the green space of the districts has an unbalanced spatial distribution. In the 1990s and 2000s, there was a greater tendency for construction in the northern districts and about 45 % of the city’s gardens were destroyed during these years, and most of the destruction occurred in the northern districts.

Moderation Effects of Coping Flexibility on the Association Between Depressive Symptoms and Suicidal Risk

Background: This study focused on poor coping flexibility, which involves the perseveration of a failed coping strategy, as a moderator of the association between depression and suicidal risk; no study has previously examined the association between coping flexibility and suicidal risk. Aims: This study examined whether individuals with lower coping flexibility would have a stronger suicidal risk when experiencing depression above a certain level. Method: Participants, who were 682 college students, answered questionnaires regarding coping flexibility, depressive symptoms, and suicidal risk. Results: Hierarchical multiple regression analyses showed that in individuals with greater depressive symptoms, lower coping flexibility was associated with higher suicidal risk, but this was not the case in individuals without depressive symptoms. Our hypothesis was supported. Limitations: Our findings cannot indicate the causal direction of the association between coping flexibility and depressive symptoms and suicidal risk. Conclusion: Our findings may be useful in understanding the association between depression and suicidal risk through coping flexibility and contribute to reductions in suicidal risk, as coping flexibility can be improved through training.