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Author(s):  
Xueqing Zhang ◽  
Jie Song ◽  
Chaolin Zha

The current project cost system requires high data scale, small amount of data and large prediction deviation. In order to improve the prediction accuracy of the whole process cost of construction project, this paper designs a whole process project cost prediction system based on improved support vector machine. In the hardware part of the system, the control core adopts arm controller S3C6410 and introduces 4G communication module to analyze the actual engineering data with the support of hardware. In the software part, the whole process cost prediction index system of the construction project is established, the index is reduced by the principal component method, and the support vector machine is improved by particle swarm optimization algorithm to realize the whole process cost prediction of the project. The system function test results show that the average prediction deviation of the designed system is 4.11%, the average prediction deviation of the cost prediction system is 3.05%, and the average prediction deviation of the system is 1.57%.


Author(s):  
И.А. Щурова ◽  
Н.А. Алексеева ◽  
С.В. Сысолятин ◽  
В.В. Малыхин

Статья посвящена способу получения флороглюцина, представляющего интерес в качестве основы для конструирования лекарственных средств, полимеров различного назначения и малочувствительного взрывчатого вещества 1,3,5-триамино-2,4,6-тринитробензола. Современным и наиболее экологичным методом получения флороглюцина является каталитическое гидрирование 1,3,5-тринитробензола на палладиевом катализаторе до 1,3,5-триаминобензола и его последующий гидролиз. Использование палладиевых катализаторов позволяет проводить восстановление в мягких условиях, но их высокая стоимость обуславливает потребность в поиске путей снижения расхода палладия и, соответственно, себестоимости процесса. В данном исследовании показано, что использование 1 %-го Pd/сибунит (50 % к массе субстрата) в сочетании с водно-ацетоновым раствором в качестве среды при проведении гидрирования способствует более длительному сохранению активности катализатора. Установлено, что оптимальное соотношение ацетона и воды находится в диапазоне от 4:1 до 7:1. В этом случае может быть проведено до 20 циклов гидрирования без добавления свежего катализатора, за счет чего удается снизить расход палладия в три раза по сравнению с другими известными методиками. Кроме того, подход позволяет исключить из схемы синтеза токсичный растворитель метанол. Триаминобензол, полученный в ходе гидрирования, без выделения подвергается гидролизу в присутствии серной кислоты с образованием флороглюцина. Изучена зависимость выхода флороглюцина от мольного соотношения серной кислоты и тринитробензола. Установлено, что оптимальное соотношение серная кислота : тринитробензол составляет 2,0-2,4 моль/моль. Суммарный выход флороглюцина составляет 76 % в пересчете на тринитробензол. The study is concerned with a synthetic method for phloroglucinol that is of great concern as a scaffold for designing medicinal drugs, different-purpose polymers and the insensitive explosive 1,3,5-triamino-2,4,6-trinitrobenzene. The current and most eco-benign method for the synthesis of phloroglucinol is through catalytic hydrogenation of 1,3,5-trinitrobenzene over the Pd catalyst to 1,3,5-triaminobenzene followed by its hydrolysis. The use of Pd catalysts allows the reduction under mild conditions, but their high cost necessitates the need to find ways how to spare the Pd usage and, consequently, the process cost. Here we demonstrated that the use of 1% Pd/Sibunite (50% to substrate weight) combined with a water-acetone solution as the medium in hydrogenation allows the catalyst to keep active longer. The optimum acetone-to-water ratio was found to be between 4:1 and 7:1. In this case, as many as 20 hydrogenation runs can be done without a fresh catalyst added whereby the Pd usage can be lowered threefold when compared to the other common methods in use. Besides, this approach allows the toxic solvent methanol to be expelled from the synthetic protocol. Triaminobenzene resulting from the hydrogenation without isolation undergoes hydrolysis in the presence of sulfuric acid to furnish phloroglucinol. The relationship between the phloroglucinol yield and the molar ratio of sulfuric acid and trinitrobenzene was also explored. The optimum sulfuric acid-to-trinitrobenzene ratio was found to be 2.0-2.4 mol/mol. The overall yield of phloroglucinol was 76% on a trinitrobenzene basis.


Author(s):  
Peizhen Hong ◽  
Qiang Xu ◽  
Jingwen Hou ◽  
Mingkai Bai ◽  
Zhiguo Zhao ◽  
...  

Abstract In 3D NAND, as the stack number increases, the process cost becomes higher and higher, and the stress problem becomes more and more serious. Therefore, the low cost and low stress plasma enhanced Tetraethyl orthosilicate (PE TEOS), compared to high density plasma (HDP) oxide, shows its superiority as pre-metal dielectric (PMD) oxide layer in 3D NAND. This paper explores the challenges in the application of PE TEOS in 3D NAND PMD oxide layer.In our experiments, both PE TEOS and HDP are employed as the PMD oxide for 3D NAND staircase protection. There is not any void found in the two oxide structures. However, oxide pitting is spotted in the subsequent diluted hydrofluoric acid wet etching in the PE TEOS split. Moreover, we observe that the top silicon nitride corrodes in hot phosphoric acid. We investigate the mechanism of PE TEOS oxide pitting and silicon nitride corroding, and propose two solutions: 1) HDP oxide + PE TEOS, and 2) PE TEOS + dry etching.Experimental results demonstrate that our solutions can well address the issue of PE TEOS oxide pitting and effectively protect the staircase structure. This work extends the application of PE TEOS oxide of which the cost and the stress are both low in 3D NAND.


2021 ◽  
Author(s):  
◽  
Ursula A. Rojas Nazar

<p>Marine Reserves (MRs) are amongst the most common tools used for marine conservation around the world. New Zealand (NZ) has 34 MRs protecting approximately 7.6% of NZ's territorial seas. In NZ the main purpose of MRs is to allow scientific research to be conducted in the absence of human disturbance. The establishment of MRs around the country produces different biological, social and economic effects in the surrounding communities. However, the majority of previous MR studies have evaluated the biological effects of protection and not the social and economic effects. This thesis investigates how established MRs are performing in terms of social, economic, social and biological goals and contributing to society‘s well-being within New Zealand. For this research I conducted research at two MRs. The Taputeranga MR (TMR) was established in 2008, and is the newest MR established in New Zealand. It is located in the Wellington region, on the Wellington south coast, and extends from Princess Bay to Quarry Bay, protecting 8.54 km² of coastal waters. Kapiti MR (KMR), which is one of the oldest MRs in New Zealand, was established in 1992 in the Wellington region, approximately 50 km north of Wellington city. It is located on the Kapiti coast in front of Paraparaumu beach. The KMR covers 20.90 km² of coastal water, divided into two parts; the largest part is 17.50 km² and the smaller part is 3.4 km².   In this thesis I am starting to explore the financial cost of the MRs (chapter 2), where I attempted to estimate all of the costs required to establish a MR. The Taputeranga MR was used as a case study along with an analysis of the management costs for four other MRs. I aimed to find predictor variables across these five MRs to explain differences in their management cost. In addition, I also estimated the displacement cost to fishermen. Results showed that the Taputeranga‘s pre-establishment process cost approximately NZ $508,000, and the establishment process cost approximately NZ $ 354,000. In addition, the average management cost across five MRs per year was around NZ $63,000 year⁻¹. With respect to the predictor variables, the Akaike Information Criterion (AICc) analysis showed that MR size best explains cost, where small MRs are more expensive to maintain than big MRs. The displacement cost was estimated as NZ $22,000 approximately per vessel.  I also researched and examined the social impacts of MRs (chapter 3). The aim of this chapter was to explore the human dimensions of the TMR and KMR and a hypothetical MR as a control area. I used a series of questionnaires with five main groups affected by the establishment of the MRs. Results showed that of the people who conducted activities close to the TMR and KMR, nobody selected either area specifically because there was a MR in the vicinity. With respect to MR knowledge, the majority of people at both MRs and at the hypothetical MR believed they knew what a MR was, however, nobody could provide a correct description of the main reasons for MR designation in New Zealand. Most groups surveyed at KMR indicated that its establishment had not personally affected them. At TMR, all groups believed they had experienced direct (personal) and indirect problems since the establishment of the MR. At the hypothetical MR, the majority of respondents perceived that its establishment would not cause any personal or family problems. I found that respondents at both MRs and the hypothetical MR believed that MRs are a good tool for protecting the environment.  I also develop a framework to understand and estimate MR goods and services by using the Millennium Ecosystem Assessment framework (chapter 4). The aim of this study was to identify and determine use and non-use values of the Taputeranga MR and Kapiti MR. At KMR and TMR I identified eight main value-categories: (1) Commercial fishing benefits from MR, (2) Nature-based tourism, (3) Education, (4) Research, (5) Public recreation, (6) Recreational fishing benefit from MR, (7) Ecosystem health, and (8) Existence – Bequest value. The existence-bequest values (non-use values) were estimated based on the public‘s willingness to pay (WTP) and found to have a mean value of NZ $61.54 at the TMR and NZ $31.45 at the KMR per household/year.  After being exploring cost of MRs, social effects of MRs and MR goods and services, I researched the biological effects of MRs. For this I examined the effect of MRs on rock lobster (Jasus edwardsii) biomass and abundance (chapter 5). I investigated how rock lobsters (RLs) (Jasus edwardsii) have responded to the protection afforded by the TMR and KMR by comparing rock lobster Catch Per Unit Effort (CPUE) between reserve and nonreserve areas. The average CPUE was higher inside both MRs than outside. Also bigger RLs were caught inside both MRs'. In addition, the TMR catches were twice as high compared with historical catches, and the KMR compared with historical catches were 1.93 times higher.  By integrating all these different chapters and methodologies I have been able to provide insights that will help in the future of conservation of MRs, by improving the level of information for better decision-making, improving the communication between decision makers and stakeholders and to build better relationships between researchers and nonextractive users of MRs. Moreover, I provide recommendations that could be useful to include within the current Marine Protected Area Policy and potentially improve it. These recommendations also attempt to minimize the time and costs involved in MRs from the pre-establishment stages, by creating effective and formal alliances between different groups of stakeholders.</p>


2021 ◽  
Author(s):  
◽  
Ursula A. Rojas Nazar

<p>Marine Reserves (MRs) are amongst the most common tools used for marine conservation around the world. New Zealand (NZ) has 34 MRs protecting approximately 7.6% of NZ's territorial seas. In NZ the main purpose of MRs is to allow scientific research to be conducted in the absence of human disturbance. The establishment of MRs around the country produces different biological, social and economic effects in the surrounding communities. However, the majority of previous MR studies have evaluated the biological effects of protection and not the social and economic effects. This thesis investigates how established MRs are performing in terms of social, economic, social and biological goals and contributing to society‘s well-being within New Zealand. For this research I conducted research at two MRs. The Taputeranga MR (TMR) was established in 2008, and is the newest MR established in New Zealand. It is located in the Wellington region, on the Wellington south coast, and extends from Princess Bay to Quarry Bay, protecting 8.54 km² of coastal waters. Kapiti MR (KMR), which is one of the oldest MRs in New Zealand, was established in 1992 in the Wellington region, approximately 50 km north of Wellington city. It is located on the Kapiti coast in front of Paraparaumu beach. The KMR covers 20.90 km² of coastal water, divided into two parts; the largest part is 17.50 km² and the smaller part is 3.4 km².   In this thesis I am starting to explore the financial cost of the MRs (chapter 2), where I attempted to estimate all of the costs required to establish a MR. The Taputeranga MR was used as a case study along with an analysis of the management costs for four other MRs. I aimed to find predictor variables across these five MRs to explain differences in their management cost. In addition, I also estimated the displacement cost to fishermen. Results showed that the Taputeranga‘s pre-establishment process cost approximately NZ $508,000, and the establishment process cost approximately NZ $ 354,000. In addition, the average management cost across five MRs per year was around NZ $63,000 year⁻¹. With respect to the predictor variables, the Akaike Information Criterion (AICc) analysis showed that MR size best explains cost, where small MRs are more expensive to maintain than big MRs. The displacement cost was estimated as NZ $22,000 approximately per vessel.  I also researched and examined the social impacts of MRs (chapter 3). The aim of this chapter was to explore the human dimensions of the TMR and KMR and a hypothetical MR as a control area. I used a series of questionnaires with five main groups affected by the establishment of the MRs. Results showed that of the people who conducted activities close to the TMR and KMR, nobody selected either area specifically because there was a MR in the vicinity. With respect to MR knowledge, the majority of people at both MRs and at the hypothetical MR believed they knew what a MR was, however, nobody could provide a correct description of the main reasons for MR designation in New Zealand. Most groups surveyed at KMR indicated that its establishment had not personally affected them. At TMR, all groups believed they had experienced direct (personal) and indirect problems since the establishment of the MR. At the hypothetical MR, the majority of respondents perceived that its establishment would not cause any personal or family problems. I found that respondents at both MRs and the hypothetical MR believed that MRs are a good tool for protecting the environment.  I also develop a framework to understand and estimate MR goods and services by using the Millennium Ecosystem Assessment framework (chapter 4). The aim of this study was to identify and determine use and non-use values of the Taputeranga MR and Kapiti MR. At KMR and TMR I identified eight main value-categories: (1) Commercial fishing benefits from MR, (2) Nature-based tourism, (3) Education, (4) Research, (5) Public recreation, (6) Recreational fishing benefit from MR, (7) Ecosystem health, and (8) Existence – Bequest value. The existence-bequest values (non-use values) were estimated based on the public‘s willingness to pay (WTP) and found to have a mean value of NZ $61.54 at the TMR and NZ $31.45 at the KMR per household/year.  After being exploring cost of MRs, social effects of MRs and MR goods and services, I researched the biological effects of MRs. For this I examined the effect of MRs on rock lobster (Jasus edwardsii) biomass and abundance (chapter 5). I investigated how rock lobsters (RLs) (Jasus edwardsii) have responded to the protection afforded by the TMR and KMR by comparing rock lobster Catch Per Unit Effort (CPUE) between reserve and nonreserve areas. The average CPUE was higher inside both MRs than outside. Also bigger RLs were caught inside both MRs'. In addition, the TMR catches were twice as high compared with historical catches, and the KMR compared with historical catches were 1.93 times higher.  By integrating all these different chapters and methodologies I have been able to provide insights that will help in the future of conservation of MRs, by improving the level of information for better decision-making, improving the communication between decision makers and stakeholders and to build better relationships between researchers and nonextractive users of MRs. Moreover, I provide recommendations that could be useful to include within the current Marine Protected Area Policy and potentially improve it. These recommendations also attempt to minimize the time and costs involved in MRs from the pre-establishment stages, by creating effective and formal alliances between different groups of stakeholders.</p>


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