Function and surface approximation based on enhanced kernel regression for small sample sets

The function approximation problem is to find the appropriate relationship between a dependent and independent variable(s). Function approximation algorithms generally require sufficient samples to approximate a function. Insufficient samples may cause any function approximation algorithm to result in unsatisfactory predictions. To solve this problem, a function approximation algorithm called Weighted Kernel Regression (WKR), which is based on Nadaraya-Watson kernel regression (NWKR), is proposed. In the proposed framework, the original NWKR algorithm is enhanced by expressing the observed samples in a square kernel matrix. The WKR is trained to estimate the weight for the testing phase. The weight is estimated iteratively and governed by the error function to find a good approximation model. Four experiments are conducted to show the capability of the WKR. The results show that the proposed WKR model is effective in cases where the target function is non-linear and the given training sample is small. The performance of the WKR is also compared with other existing function approximation algorithms, such as artificial neural networks (ANN)

High yield expression in a recombinant E. coli of a codon optimized chicken anemia virus capsid protein VP1 useful for vaccine development

<p>Abstract</p> <p>Background</p> <p>Chicken anemia virus (CAV), the causative agent chicken anemia, is the only member of the genus <it>Gyrovirus </it>of the <it>Circoviridae </it>family. CAV is an immune suppressive virus and causes anemia, lymph organ atrophy and immunodeficiency. The production and biochemical characterization of VP1 protein and its use in a subunit vaccine or as part of a diagnostic kit would be useful to CAV infection prevention.</p> <p>Results</p> <p>Significantly increased expression of the recombinant full-length VP1 capsid protein from chicken anemia virus was demonstrated using an <it>E. coli </it>expression system. The VP1 gene was cloned into various different expression vectors and then these were expressed in a number of different <it>E. coli </it>strains. The expression of CAV VP1 in <it>E. coli </it>was significantly increased when VP1 was fused with GST protein rather than a His-tag. By optimizing the various rare amino acid codons within the N-terminus of the VP1 protein, the expression level of the VP1 protein in <it>E. coli </it>BL21(DE3)-pLysS was further increased significantly. The highest protein expression level obtained was 17.5 g/L per liter of bacterial culture after induction with 0.1 mM IPTG for 2 h. After purification by GST affinity chromatography, the purified full-length VP1 protein produced in this way was demonstrated to have good antigenicity and was able to be recognized by CAV-positive chicken serum in an ELISA assay.</p> <p>Conclusions</p> <p>Purified recombinant VP1 protein with the gene's codons optimized in the N-terminal region has potential as chimeric protein that, when expressed in <it>E. coli</it>, may be useful in the future for the development of subunit vaccines and diagnostic tests.</p

Effect of operating parameter on clarification of bambangan juice using enzymatic treatment of juice quality

Bambangan juice that are currently available in local market is relatively viscous, turbid, and cloudy and tend to settle during storage after bottling of the juice. The turbidity and viscosity of bambangan juice might be due to the presence of polysaccharides in the juice such as pectin and starch, which would lead to instability and deterioration. Clarification is necessary to obtain a bright, clear product with low viscosity which generally can be conducted through enzymatic treatment. Therefore, this study aims to determine the best operating parameters (enzyme concentration, incubation temperature, and incubation time) for clarification of bambangan juice using pectinase from Aspergillus aculeatus. The juice qualities were evaluated based on yield and physicochemical properties. The best operating parameters for bambangan juice clarification using pectinase were obtained at 0.10% v/v enzyme concentration, temperature of 40°C, and incubation time of 30 minutes. Under these conditions, a significant improvement in juice qualities was achieved in terms of yield, clarity, and colour (L*, a*, b*) with values of 87%, 0.5, L* - 61.1; a* - 2.7; b* - 1.4, respectively

Atomistic nucleation sites of Pt nanoparticles on N-doped carbon nanotubes

[[abstract]]The atomistic nucleation sites of Pt nanoparticles (Pt NPs) on N-doped carbon nanotubes (N-CNTs) were investigated using C and N K-edge and Pt L3-edge X-ray absorption near-edge structure (XANES)/extended X-ray absorption fine structure (EXAFS) spectroscopy. Transmission electron microscopy and XANES/EXAFS results revealed that the self-organized Pt NPs on N-CNTs are uniformly distributed because of the relatively high binding energies of the adsorbed Pt atoms at the imperfect sites. During the atomistic nucleation process of Pt NPs on N-CNTs, stable Pt–C and Pt–N bonds are presumably formed, and charge transfer occurs at the surface/interface of the N-CNTs. The findings in this study were consistent with density functional theory calculations performed using cluster models for the undoped, substitutional-N-doped and pyridine-like-N-doped CNTs.[[journaltype]]國外[[incitationindex]]SCI[[booktype]]紙本[[countrycodes]]GB

The Risk of Stroke after Percutaneous Vertebroplasty for Osteoporosis: A Population-Based Cohort Study

PURPOSE: To investigate the incidence and risk of stroke after percutaneous vertebroplasty in patients with osteoporosis. METHODS: A group of 334 patients with osteoporosis, and who underwent percutaneous vertebroplasty during the study period, was compared to 1,655 age-, sex- and propensity score-matched patients who did not undergo vertebroplasty. All demographic covariates and co-morbidities were deliberately matched between the two groups to avoid selection bias. Every subject was followed-up for up to five years for stroke. Adjustments using a Cox regression model and Kaplan-Meier analyses were conducted. RESULTS: A total of 1,989 osteoporotic patients were followed up for 3,760.13 person-years. Overall, the incidence rates of any stroke, hemorrhagic stroke and ischemic stroke were 22.6, 4.2 and 19.6 per 1,000 person-years, respectively. Patients who underwent vertebroplasty were not more likely to have any stroke (crude hazard ratio = 1.13, p = 0.693), hemorrhagic stroke (HR = 2.21, p = 0.170), or ischemic stroke (HR = 0.96, p = 0.90). After adjusting for demographics, co-morbidities and medications, the vertebroplasty group had no significant difference with the comparison group in terms of any, hemorrhagic and ischemic strokes (adjusted HR = 1.22, 3.17, and 0.96, p = 0.518, 0.055, and 0.91, respectively). CONCLUSIONS: Osteoporotic patients who undergo percutaneous vertebroplasty are not at higher risk of any stroke in the next five years after the procedure

Influence of curing temperature on the bonding strength of heat-treated plywood made with melamine-urea-formaldehyde and phenol–formaldehyde resins

Melamine-urea-formaldehyde resin (MUF) and phenol–formaldehyde resin (PF) were prepared in the laboratory. Their curing behavior was analyzed by differential scanning calorimetry (DSC). MUF resin was then cured at 110, 120, and 130 °C, while PF resin was cured at 135, 150, and 165 °C. The dry and wet bonding strength of plywood made by hot-pressing at different temperatures and heat-treatment at 200 and 250 °C were measured. DSC results show that the PF resin had a more obvious exothermic peak than the MUF resin during heat scanning. Fourier transform infrared spectroscopy analysis shows that MUF and PF resins cured at higher temperature undergo more condensation reactions. Solvent dissolution test shows that PF resin cured at 135 °C has a weight retention similar to that of resins cured at 150 and 165 °C. However, using a temperature of 120 °C was better than 110 and 130 °C for MUF resin. Thermogravimetric analysis results show that PF resin had better heat resistance than MUF resin. The curing temperature did not influence the thermal degradation behavior of cured resins. However, increasing the curing temperature resulted in higher thermal stability. Heat treatment decreased the bonding strength of plywood. However, the bonding strength still met the requirement of the CNS 1349 standard when heat-treated at 200 °C

Computer generation of negative binomial variates by envelope rejection

This paper proposes an envelope rejection method for computer sampling from the negative binomial distribution, with index parameter [alpha] and probability parameter p, based on a simple probability distribution inequality. Comparative timings with existing methods of generating NB variates show that the proposed method is comparable or faster when [alpha] is not too large ([alpha] 0.7.

Fundamental studies on the manufacture of wood adhesives made of tannin copolymer from the agriculture and forest residues

本研究乃探討相思樹、台灣泡桐、木油桐、山黃麻等４種闊葉樹樹皮及杉 木、台灣杉等２種針葉樹樹皮，及稻殼、蔗渣等２種農業廢料之化學組成 分、萃取成分中反應性酚物質含量及其與甲醛之反應性、酚-萃取物-甲醛 共聚合樹脂(PTF)之熱硬化性及抽出物或其共聚合樹脂應用於木質材料膠 合之可行性。所得重要結果可歸納如下：1.４種闊葉樹樹皮之熱水萃取物 含量約13.1﹪∼18.3﹪，1﹪NaOH萃取物之 含量約46.9﹪∼57.6﹪。杉 木及台灣杉２種針葉樹樹皮之熱水萃取物含 量則內皮部約10.5﹪∼11.8 ﹪，外皮部約3.9﹪∼5.0﹪，1﹪NaOH萃取物 之含量則外皮部約33.0﹪ ∼36.1﹪，內皮部約24.0﹪∼30.6﹪。熱水萃 取物中反應性酚物質含量 以相思樹幹材樹皮之 66.3﹪最高，而木油桐 及山黃麻含量亦在50﹪以 上，杉木及台灣杉則分別為21.6﹪及13.8﹪， 然台灣泡桐僅12.4﹪，稻 殼及蔗渣幾不含反應性酚物質。1﹪NaOH萃取物 中反應性酚物質含量則 以山黃麻 64.4﹪最高，相思樹為61.5﹪，杉木及 台灣杉之外皮亦分別 達62.9﹪及59.1﹪，然其內皮萃取物中僅含37.6﹪ 及10.9﹪，台灣泡桐 亦僅含18.6﹪。反應性酚物質佔樹皮絕乾重之百分 比則以山黃麻之37.1 ﹪最高，相思樹33.2﹪次之，杉木外皮為22.7﹪。2.各試料之熱水萃取物 中均含有單寧成分，其中相思樹、木油桐、山黃麻 及杉木內皮含有較多 縮合型單寧，台灣泡桐則含有較多加水分解型單寧 ，稻殼及蔗渣則兩種 單寧含量均較少。3.各試料萃取物中之單寧經乙醯化處理後之重量平均分 子量分別為，山黃 麻(8056)、相思樹(5128)、木油桐(4537)、台灣泡 桐(2527)、杉木(2078 )、台灣杉(1795)、稻殼(2403)。4.比較不同萃取 藥劑之萃取效果，以NaOH溶液之萃取量最高，且隨其濃度 增大，萃取量 增加，Na2CO3溶液之萃取量次之。提高萃取溫度可增加其 萃取量，延長 萃取時間對萃取量增加之效果不明顯。5.相思樹樹皮之鹼萃取物與甲醛反 應時，減少甲醛添加mole數，則反應過 程中易發生膠化現象，添加酚共 同反應則可延緩膠化現象發生。在萃取 物溶液液pH值11.0，甲醛與萃取 物之mole比6.0時，加熱反應２小時後， 每mole萃取物約可消耗1.3mole 甲醛。6.酚-萃取物-甲醛共聚合樹脂(PTF)熱硬化時之最高放熱峰溫度及 反應熱均 較PF樹脂為低。此共聚合樹脂合成時，隨萃取物取代量增加或 NaOH使用 量減小，其加成反應之速度減慢，合成樹脂熱硬化時之反應熱 降低，然 最高放熱峰溫度則隨NaOH使用量增加而增高。7.萃取物與RF樹 脂混合時可降低萃取物之粘度，並縮短RF樹脂之膠化時間 ，在RF樹脂- 萃取物之固體成分混合比為100/100時，其常態膠合強度大 多在100Kgf/ cm^2以上，且其常態、耐60℃水及耐沸水返覆試驗之木破率 均遠大於相 同固形分含量之RF樹脂。8.酚-相思樹樹皮萃取物-甲醛共聚合樹脂合成時 以NaOH/P之mole比為0.7者 之膠合性質較佳，其合板之沸水浸水膠合強 度在萃取物取代量40﹪時仍 可達10.2Kgf/cm^2，常態膠合強度則在萃取 物取代量至60﹪時仍有良好 尼膠合效果。各不同種類萃取物所合成之 PTF共聚合樹脂均可達CNS 8060 號標準中對之合板常態膠合強度之要求 ，沸水浸水之膠合強度則以山黃 麻樹皮萃取物為原料所合成者最佳，可 達12.8Kgf/cm^2以上，以相思樹 、木油桐、杉木、台灣杉樹皮萃取物及 稻殼萃取物為原料者，在萃取物 取代量40﹪時亦可達9.2Kgf/cm^2以上 ，且均大於PF樹脂之沸水浸水膠合 強度。以台灣泡桐或蔗渣為原料者， 則耐水膠合強度偏低。9.以相思樹樹皮萃取物為原料所合成之PTF共聚合 樹脂應用於粒片板製造時 ，以NaOH/P之mole比為0.55者成板性質最佳， 在熱壓溫度180℃，熱壓時 間６分鐘時，其常態、耐沸水之靜曲強度、 彈性係數、內聚強度等均可 達CNS 2215號標準中對200型粒片板之要求 以上，且其各項性質均優於PF 樹脂在180℃熱壓８分鐘或200℃熱壓６分 鐘者。In this study, the chemical components of four species of hard- wood bark (acacia, Taiwania paulownia, wood oil tree and Indiacharcoal trema), two kinds of conifer bark (Taiwania and Chinafir) and two species of agriculture residue (rice hull andbagasse) were analyzed. Their phenolic material contents, thereactivities with formaldehyde, the hot curing properties ofphenol-extractives-formaldehyde copolymers, and the probabili- ties of these extractives and their copolymers used in thegluing of wood based materials were also investigated.The results are summarized as follows:1.The contents of hot water extractives and 1% NaOH solubili- ties were between 13.1-18.3% and 46.9-57.6% respectively for four species of hardwood barks used in this study. The con- tents of hot water extractives of China fir and Taiwania were between 10.5-11.8% for the inner barks and 3.9-5.0% for the outer barks, and the contents of 1% NaOH solubilities of these two coniferous woods were between 33.0-36.1% for outer barks and 24.0-30.6% for inner barks. In the hot water extractives, acacia had the most phenolic material content (66.3%) than the others, wood oil tree and India charcoal trema having more than 50%, China fir (21.6%) and Taiwania (13.8%), Taiwania paulownia only having 12.4%, rice hull and bagasse almost did not contain phenolic substance. In the 1% NaOH soluble materials, India charcoal trema had 64.4% of phenolic material, which was the highest content of all samples. Acacia, outer bark of Taiwania and China fir were about 60%, but Taiwania paulownia and the inner bark of Taiwania and China fir showed lower values. Regarding to the ratio of dry bark weight to phenolic material, India charcoal trema was the highest(37.1%), acacia was the next (33.2%), and then outer bark of China fir was the lowest.2.All samples of hot water extractives contained tannin. Among these samples, acacia, wood oil tree, India charcoal trema and inner bark of China fir had more condensed tannin, and Taiwan paulownia had more hydrolizable tannin, but these two kinds of tannins were rare for both rice hull and bagasse.3.The average molecular weights of acetylated tannins extracted from barks of India charcoal trema, acacia, wood oil tree, Taiwan paulownia, China fir, Taiwania, and from rice hull were 8056, 5128, 4537, 2527, 2078, 1795 and 2403 respectively.4.The yields of soluble materials extracted by NaOH solution were higher than that of the other chemical solutions, and they were increased with the increments of the concentration of NaOH. The yield of soluble materials extracted by Na2CO3 was the next. Elevating the extraction temperature would increase the yield, but prolonging the time of extraction would not have conspicuous effects on the enhancement of the amount of extractive.5.During the reaction of alkaline soluble material of acacia bark with formaldehyde, it would decrease the molar ratio of formaldehyde added, therefore it would tend to gel at the stage of reaction, but when phenol had been added to coreac- tion, the phenomenon of gelation would be prolonged. At the pH 11.0 and the molar ratio of formaldehyde to tannin monomer was 6.0, each mole of tannin monomer would consume 1.3 mole of formaldehyde after two hours reaction.6.When alkaline soluble materials were blended with RF, the viscosity of alkaline soluble materials would be decreased, and the gelation time of RF resin would be shortened. When the blending ratios of RF to extractives by solid component were 100/100, the dry bonding strengths would be higher than 100Kgf/cm^2, and the wood failures test at dry or soaked in 60℃ water or repeatedly soaked in boiling water would be higher than RF resins at the same solid content.7.The maximum temperature of exothermic peak and the heat of curing of PTF copolymer resins were lower than that of PF resins. During the synthesizing of PTF copolymer resins, increament of the amount of extractive or decreament of the NaOH added would slow down the rate of addition reaction and decrease the heat of curing, but the maximum temperature of exothermic peak would increase with the amount of NaOH added.8.The copolymers(PTF) of phenol-acacia bark extractive-forma- ldehyde synthesized with the molar ratio of NaOH/P of 0.7 had better bonding properties than the others. The boiling bonding strength of plywoods was 10.2Kgf/cm^2 at 40% of extractives replacement, and they had better dry bonding strength even the extractives replacement up to 60%. The dry bonding strength of plywoods made with various PTF copolymers which synthesized by different kinds of extractives could pass the requirements of CNS standard. The boiling bonding strength of plywoods made with PTF copolymers which copolymerized with India charcoal trema bark extractives could reach up to 12.8 Kgf/cm^2, this value was the highest among all kinds of PTF copolymers. The PTF copolymers synthesized by the extractive of bark such as acacia, wood oil tree, China fir, Taiwania, or by the extractive of rice hull with 40% of replacement of phenol by extractives had the boiling bonding strength of plywoods exceed 9.2Kgf/cm^2, these were better than that of PF resins. The PTF copolymers synthesized by Taiwan paulownia or bagasse had the poorest water resistance bonding strength.9.When the copolymer resins of phenol-acacia bark extractive- formaldehyde were used in the manufacture of particleboard, the molar ratio 0.55 of NaOH/P had the best properties than the others. Hot-pressing temperature at 180℃ for 6 minutes, the MOR, MOE, IB strength at dry and wet were over the requirements of CNS 2215 for 200 type particleboard, and all of these properties would be better than the boards made with PF resins by hot-pressing temperature at 180℃ for 8 minutes or hot-pressing temperature at 200℃ for 6 minutes.封面 目錄 圖目次 表目次 摘要 英文摘要 第一章 前言 第二章 文獻回顧 第三章 樹皮、稻殼及蔗渣之化學組成分分析及萃取方法比較 第一節 試驗材料與方法 一、試驗材料 二、試驗方法 (一)材料準備 (二)化學組成分含量測定 (三)萃取物中反應性酚物質含量測定 (四)萃取物中單寧成分存在之檢定 (五)萃取物中單寧成分之分子量側定 (六)萃取條件對萃取效果影響之測定 1.萃取藥劑、溫度及時問 2.試料之顆粒大小 3.不同過濾法之比較 4.重複萃取之效果 (七)大量萃取及濃縮、乾燥 (八)萃取物之粘度測定 第二節 結果與討論 一、各試料之化學組成分分析 二、萃取物中反應性酚物質之含量 三、萃取物之定性分析 四、單寧之分子量 五、不同萃取條件之萃取效果 (一)萃取藥劑及萃取溫度、時間之影響 (二)試料顆拉大小之影響 (三)不同過濾法之比較 (四)重複萃取之效果 六、萃取物之粘度 (一)測定條件對萃取物粘度之影響 (二)試料種類對粘度之影響 (三)萃取藥劑對粘度之影響 (四)萃取液之pH值對粘度之影響 (五)添加酚對萃取物粘度之影響 第四章 萃取物與甲醛之反應性 第一節 試驗材料與方法 一、試驗材料 二、試驗方法 (一)材料準備 (二)萃取處理 (三)萃取液之嘖霧乾燥 (四)萃取物與甲醛之反應性試驗 (五)反應液中甲醛含量測定 第二節 結果與討論 第五章 酚-萃取物-甲醛共聚合樹脂之熱硬化性 第一節 試驗材料與方法 一、試驗材料 二、試驗方法 (一)材料準備及萃取物製備 (二)酚甲醛樹脂(PF)之合成 (三)酚-萃取物-甲醛共聚合樹脂(PTF)之合成 (四)合成樹脂之膠化時問測定 (五)合成樹脂之熱示差掃描卡量分析 (六)熱硬化動力學資料分析 第二節 結果與討論 一、各合成樹脂之膠化時間 二、各合成樹脂之DSC熱分析 (一)PF樹脂之熱硬化性 (二)酚-相思樹樹皮萃取物-甲醛共聚合樹脂之熱硬化性 (三)不同萃取物種類共聚合樹脂之熱硬化性 三、各合成樹脂熱硬化時之溫度、時間與硬化率之關係 第六章 萃取物在木材膠合之應用 第一節 萃取物應用於常溫硬化型膠合劑及其木材膠合 一、試驗材料與方法 (一)試驗材料 (二)試驗方法 1.材料準備及萃取物製備 2.間苯二酚甲醛樹脂(RF)之合成 3.RF樹脂-萃取物混合膠合剖之調配 4.性質測定 二、結果與討論 (一)萃取物之性質 (二)RF樹脂之性質及膠合強度 (三)RF樹脂-萃取物混合膠合劑之性質及接合強度 第二節 萃取物應用於加熱硬化型膠合劑之製備及其在木質板類製造之應用 一、合扳之製造及其性質測定 (一)試驗材料與方法 1.試驗材料 2.試驗方法 (1)材料準備及萃取物製備 (2)酚甲醛樹脂(PF)之合成 (3)酚-萃取物-甲醛共聚合樹脂(PTF)之合成 (4)合成樹脂之性貿測定 (5)膠合劑之調配及存合性質測定 (二)結果與討論 1.合成樹脂之性質 2.各合成樹脂性質之計量分析 3.PF樹脂及酚-萃取物-甲醛共聚合樹脂之膠合性質 (1)PF樹脂之合板膠合強度 (2)酚-相思樹樹皮萃取物-甲醛共聚合樹脂之合板膠合強度 (3)不同種類酚-萃取物-甲醛共聚合樹脂之合板膠合強度 二、粒片板之製造及其性質測定 (一)試驗材料與方法 1.試驗材料 2.試驗方法 (1)萃取物之製備 (2)膠合劑之合成 (3)合成樹脂之性質測定 (4)粒片物之製備及尺寸分析 (5)粒片板之製造 (6)粒片板之性質測定 (二)結果與討論 1.合成樹脂之性質 2.拉片尺寸分析 3.粒片板之性質 (1)PF膠拉片板之性質 (2)萃取物-甲醛混合膠合劑製造粒片板之性質 (3)PF-萃取物混合膠合劑製造粒片板之性質 (4)PTF共聚合膠合劑製造拉片板之性質 第七章 結論 第八章 參考文

Development of a hybrid artificial neural network - naive bayes classifier for binary classification problem of imbalanced datasets

This paper presents a hybrid approach that consists of two different methods from machine learning technique, which are the Artificial Neural Network (ANN) and Naïve Bayes. The proposed technique is purposely developed for classifying the two classes of imbalanced datasets. Architecture of ANN is based on a single layer feedforward ANN for binary classification and the learning algorithm is assisted by the Particle Swarm Optimization (PSO) algorithm. As a main classifier, the Naïve Bayes is still being kept by using a conventional method. Consequently, by comparing with the individual classifiers that are used in this paper, the proposed approach is capable of improving the prediction performance that is evaluated by geometric mean (Gmean) as the performance measure