Soil carbon sequestration under long-term rice-based cropping systems of purple soil in Southwest China

Carbon sequestration in agricultural soils is a complex process controlled by farming practices, climate and some other environment factors. Since purple soils are unique in China and used as the main cropland in Sichuan Basin of China, it is of great importance to study and understand the impacts of different fertilizer amendments on soil organic carbon（SOC） changes with time. A research was carried out to investigate the relationship between soil carbon sequestration and organic carbon input as affected by different fertilizer treatments at two long-term rice-based cropping system experiments set up in early 1980 s. Each experiment consisted of six identical treatments, including（1） no fertilizer（CK）,（2） nitrogen and phosphorus fertilizers（NP）,（3） nitrogen, phosphorus and potassium fertilizers（NPK）,（4） fresh pig manure（M）,（5） nitrogen and phosphorus fertilizers plus manure（MNP）, and（6） nitrogen, phosphorus and potassium fertilizers plus manure（MNPK）. The results showed that annual harvestable carbon biomass was the highest in the treatment of MNPK, followed by MNP and NPK, then M and NP, and the lowest in CK. Most of fertilizer treatments resulted in a significant gain in SOC ranging from 6.48 to 2 9.13% compared with the CK, and raised soil carbon sequestration rate to 0.10–0.53 t ha–1 yr-1. Especially, addition of manure on the basis of mineral fertilizers was very conducive to SOC maintenance in this soil. SOC content and soil carbon sequestration rate under balanced fertilizer treatments（NPK and MNPK） in the calcareous purple soil（Suining） were higher than that in the acid purple soil（Leshan）. But carbon conversion rate at Leshan was 11.00%, almost 1.5 times of that（7.80%） at Suining. Significant linear correlations between soil carbon sequestration and carbon input were observed at both sites, signifying that the purple soil was not carbon-saturated and still had considerable potential to se questrate more carbon.

MICROSTRUCTURES AND PROPERTIES OF DZ40M Co-BASED SUPERALLOY AFTER LONG-TERM AGEING AT 850℃

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Evidence-Based Practice and Job Satisfaction of Nurses in Long-Term Care

Purpose: The purpose of this study was to identify the relationship between evidence-based practice (EBP) and job satisfaction among nurses working in long-term care facilities. Methods: The study used a descriptive cross-sectional design. A total of 146 nurses working in 6 long-term care facilities in South Korea self-reported their perception of EBP implementation, barriers to research utilization, and job satisfaction. Results: The level of job satisfaction was higher in nurses who were single, older, more experienced, and had a higher income. Lower perceived barriers to research utilization were associated with greater job satisfaction. However, there was no significant relationship between a level of EBP implementation and job satisfaction. Factors influencing job satisfaction included lower barriers to the organization and communication domains of research utilization, being unmarried and older. Conclusion: Decreasing barriers to research utilization may improve the job satisfaction of nurses working in long-term care facilities.

RESEARCH ON WEIGHTED PRIORITY OF EXEMPLAR-BASED IMAGE INPAINTING

The priority of the filled patch play a key role in the exemplar-based image inpainting, and it should be determined firstly to optimize the process of image inpainting. A modified image inpainting algorithm is proposed by weighted-priority based on the Criminisi algorithm. The improved algorithm demonstrates better relationship between the data term and the confidence term for the optimization of the priority than the classical Criminisi algorithm. By comparing the effect of the inpainted images with different structure, conclusion can be drawn that the optimal priority should be chosen properly for different images with different structures.

Block-Based Adaptive Image Steganography Using LSB Matching Revisited

Recently, an edge adaptive image stegano- graphic method based on least significant bit （LSB） matching revisited （EA-LSBMR） has been proposed, which holds good visual quality and proper security under appropriate embedding rates. However, from the extensive experiments to EA-LSBMR, we find that the discrete Fourier transform （DFT） spectrum of pixelpairs differences histogram still reveals the presence of a secret message even in a low embedding rate. To enhance the security, a modified scheme is proposed in this paper, which can defeat the above-mentioned analysis and keep the visual quality better than EA-LSBMR in higher embedding rates. Experimental results using a latest universal steganalysis method have demonstrated the proposed method＇s good performance.

Analytical Modeling of Base Transit Time of SiGe HBTS Including Concentration Dependent Bandgap Narrowing Effect

Heterojunction Bipolar Transistors with SiGe base and Si emitter and collector have increasingly become important in high speed applications in electronics due to better performance of these devices with a modest increase in complexity of fabrication process. Speed of these devices is mainly determined by transit time of minority carriers across the device. Base transit time is the most important component of the total transit time. An analytical model is developed here to predict the variation of base transit time with Ge content, base doping concentration, temperature, and other device parameters. Studies have been made for both uniform and exponential doping distributions with different Ge profiles in the base region. Band gap narrowing effect due to high doping concentration is also taken into account in the model.

Efficient Cloud Image Retrieval System Using Weighted-Inverted Index and Database Filtering Algorithms

With the advance of multimedia technology and communications, images and videos become the major streaming information through the Internet. How to fast retrieve desired similar images precisely from the Internet scale image/video databases is the most important retrieval control target. In this paper, a cloud based content-based image retrieval （CBIR） scheme is presented. Database-categorizing based on weighted-inverted index （DCWII） and database f＇dtering algorithm （DFA） is used to speed up the features matching process. In the DCWII, the weights are assigned to discrete cosine transform （DCT） coefficients histograms and the database is categorized by weighted features. In addition, the DFA filters out the irrelevant image in the database to reduce unnecessary computation loading for features matching. Experiments show that the proposed CBIR scheme outperforms previous work in the precision-recall performance and maintains mean average precision （mAP） about 0.678 in the large-scale database comprising one million images. Our scheme also can reduce about 50% to 85% retrieval time by pre-filtering the database, which helps to improve the efficiency of retrieval systems.

Base-X Notation and Tri-Value Logic

This paper introduces the base-X notation and discusses the conversion between numbers of different bases. It also introduces the tri-value logic that is associated with the base-3 system.

长期施用化肥对南方稻田土壤酸化和盐基离子损失的影响

【目的】利用长期定位试验评估氮、磷、钾化肥配施对土壤酸化程度、交换性铝产生量和盐基离子损失量的影响,为维持土壤健康生产和农田可持续利用提供依据。【方法】采用始于1984年的肥料长期定位试验,选取不施肥(CK),磷钾肥配施(PK)、氮磷肥配施(NP)、氮钾肥配施(NK)和氮磷钾肥配施(NPK)5个处理,采集每个处理的0—10、10—20、20—40和40—60 cm土层土样,分析土壤pH、交换性酸、交换性盐基离子总量、交换性盐基离子累积量、酸碱缓冲容量和酸化速率等指标。【结果】经过连续33年不同施肥处理的定向培育后,CK、PK、NP、NK和NPK处理0—20 cm土层pH较试验前分别下降0.82、0.91、1.13、0.8和1.19个pH单位,导致表层土壤明显酸化,酸化速率分别达到了1.10、1.22、1.46、1.13和1.58 kmol·hm^(-2)·a^(-1)。与CK处理相比,NP和NPK处理的0—40 cm土层显著酸化,土壤pH分别下降0.28—0.38和0.35—0.46个单位,土壤交换性酸分别增加了35.5%—110.0%和30.4%—120.5%,特别是交换性铝分别增加56.2%—157.6%和73.7%—189.8%,土壤交换性盐基离子总量分别减少6.3%—14.9%和9.9%—13.2%,盐基饱和度降低2.9—14.9和2.6—15.4个百分点;NK处理的0—20 cm土层略有酸化,土壤交换性酸增加53.5%—55.0%,盐基饱和度降低6.0—7.1个百分点;PK处理的0—60 cm土壤酸化均不明显,土壤交换性酸增加和交换性盐基离子总量减少差异均不显著。【结论】长期施化肥对土壤酸化程度和盐基离子损失量的影响表现出明显差异。其中,NPK和NP长期处理加剧土壤酸化进程,且酸化深度到达40 cm,盐基离子损失量和交换性铝的产生量大幅增加,初步估算施用化肥导致土壤pH降低1个单位,土壤交换性盐基离子的损失量约是土壤交换性酸增加量的一倍左右;长期磷钾配施、氮钾配施对土壤酸化的影响较小,盐基离子损失量和交换性铝增加量相对较少。

基于周期特征提取的DLnet预测模型研究

现有的预测方法很少独立分析能源消耗的周期性特征。本文提出了一个短期办公建筑能耗预测模型(DLnet),以解决周期性能耗数据利用效率低下的问题。首先,利用STL对能耗数据的周期成分进行分解,通过网格搜索算法寻找能耗数据的最优周期;然后,根据最优周期构建周期块;再根据周期块的数据形状构建时间序列块数据;之后,利用长短期记忆(LSTM)对时间序列块数据和周期块数据进行训练和学习;最后,通过线性回归将时间序列块数据和周期块数据的预测结果进行融合。事实证明,所提出的模型的4个预测精度指标分别比LSTM模型高7%,21%,25%和26%。

长期时效对镍铁基高温合金组织和冲击韧性的影响

高参数超超临界机组是未来火电技术的核心研究和发展方向,新型镍铁基高温合金HT650T(GH4650T)是650℃等级机组过热器、再热器用重要的候选材料,本研究将固溶态HT650T合金管材分别置于650℃和700℃进行0~10000 h的等温时效实验,分析了时效过程中合金强化相、晶内和晶界碳化物等微观组织以及室温冲击韧性的变化趋势。结果表明:时效过程中合金主要强化相γ′相的粗化受基体元素扩散控制,粗化动力学遵循Lifshitz-Slyozov-Wagner熟化规律。随时效时间的延长,晶界MX相的变化不明显,M_(23)C_(6)析出量增多且宽化,晶界碳化物在时效至10000 h仍保持不连续的形态,未发现有害相析出。室温冲击韧性的下降与晶界碳化物的粗化具有关联性,时效后期冲击韧性趋于稳定,表明HT650T具有良好的组织和性能稳定性,研究结果可为HT650T合金的工程应用提供理论和实验依据。

基于注视转移学习的视频注视目标检测

视频注视目标检测,需要估计视频帧中的人所注视目标的位置。在不同的时间,人会注视不同的目标。在两个注视目标转移的时间段内,人并没有注视特定的目标。基于图像Transformer的注视目标检测方法,忽略了抑制注视转移现象。注视转移中的注视方向,会干扰注视目标的真实位置估计。为了实现视频注视目标检测,提出一种基于注视转移的模型,该模型包括注视方向引导模块,注视转移时间融合模块。在注视方向引导模块中,注视目标位置被用于估计注视方向热图。该模块使用注视方向热图来引导注视目标热图生成,这有利于抑制非注视方向的目标响应,提高注视目标定位的准确性。在注视转移时间融合模块中,注视目标热图随着时间变化会产生时空热图。该模块对时空热图采用双向时空卷积长短期记忆网络(LSTM),产生时空记忆融合的注视目标热图,来描述时空热图中注视目标的变化过程。该模块将注视转移时间段描述为高斯时间模型。针对注视转移的时间长度不确定的问题,该模块设计高斯时间融合方法,来估计出注视转移的视时间长度和注视转移的开始和结束时间。注视转移时间段的准确定位,抑制了注视转移现象对注视目标位置估计的干扰。该模型训练使用了注视方向损失、注视目标存在损失、注视目标热图损失,以及注视转移时间定位损失。实验采用GazeFollow和VideoAttentionTarget数据集。实验结果表明基于注视转移的模型,优于基于图像Transformer的注视目标检测方法。

应对人口老龄化的长期护理保险的理念与路径

长期护理保险是国家为了应对人口老龄化作出的重要制度安排,其以保障老年人的护理需求为宗旨。不同于“失能”这一针对个体权益的单向性概念,护理需求以依赖风险为核心,涵摄了风险的两个面向:护理依赖者与被依赖的家庭成员。长期护理保险旨在预防该风险给护理依赖者及其家庭成员带来的不利后果,其应当作为家庭责任的分担机制而非替代机制。在制度设计上,应以重视与支持家庭为基本理念,充分考虑护理需求在家庭内部获得满足的可能性,为家庭护理提供相应的支持。现阶段,宜将老年人作为制度的主要保障对象,以老年人的护理需求为中心提供保障,明确居家护理优先原则,在减轻个人、家庭护理负担的同时,提升家庭承担护理责任的能力。

2D matrix based indexing with color spectralhistogram for efficient image retrieval

A novel content based image retrieval （CBIR） algorithmusing relevant feedback is presented. The proposed frameworkhas three major contributions： a novel feature descriptor calledcolor spectral histogram （CSH） to measure the similarity betweenimages; two-dimensional matrix based indexing approach proposedfor short-term learning （STL）; and long-term learning （LTL）.In general, image similarities are measured from feature representationwhich includes color quantization, texture, color, shapeand edges. However, CSH can describe the image feature onlywith the histogram. Typically the image retrieval process starts byfinding the similarity between the query image and the imagesin the database; the major computation involved here is that theselection of top ranking images requires a sorting algorithm to beemployed at least with the lower bound of O（n log n）. A 2D matrixbased indexing of images can enormously reduce the searchtime in STL. The same structure is used for LTL with an aim toreduce the amount of log to be maintained. The performance ofthe proposed framework is analyzed and compared with the existingapproaches, the quantified results indicates that the proposedfeature descriptor is more effectual than the existing feature descriptorsthat were originally developed for CBIR. In terms of STL,the proposed 2D matrix based indexing minimizes the computationeffort for retrieving similar images and for LTL, the proposed algorithmtakes minimum log information than the existing approaches.

基于临床护理分类系统的PICC相关性血栓预防护理知识库的构建

目的在PICC相关性血栓预测模型构建完成的基础上,应用循证方法学构建PICC相关性血栓预防护理知识库,为实现PICC相关性血栓预见性风险管理提供决策基础。方法以2020年发表的成人恶性肿瘤患者PICC血栓预防的最佳证据总结为基础,补充检索BMJ、JBI、RNAO、INS以及中国知网等国内外数据库和专业协会网站中关于PICC相关性血栓预防护理的所有证据,检索时限为2019年11月1日—2023年4月1日,对新纳入的文献进行质量评价和证据提取,并与现有最佳证据总结进行汇总、整理,形成知识库初稿,通过专家会议修改初稿,确定知识库终稿。按照临床护理分类系统编码规则,对知识库初稿内容进行编码。结果以PICC相关性血栓预测模型为评估工具,预防护理知识库终稿包括1项护理诊断、18项具体护理措施和4种护理结局。结论PICC相关性血栓预防护理知识库具有专业性、科学性与实用性,为临床护士提供科学决策。

儿童家庭机械通气管理的证据总结

目的:检索、评价并总结儿童家庭机械通气管理的证据,对需要家庭机械通气的儿童提供标准化的评估和管理证据。方法:基于PIPOST模式确定循证问题,按照“6S”模型对国内外相关学会、指南、数据库网站进行文献检索,检索时限为建库至2023年8月。对文献质量进行评价,并提取相关证据。结果:共纳入11篇文献,其中指南4篇、专家共识2篇、系统评价1篇、队列研究2篇以及类实验性研究2篇。从儿童家庭机械通气管理的前期准备、照顾者培训、设备与安全、家庭护理技术、随访监测以及长期发展6个方面共形成28条证据。结论:儿童由医院过渡到家庭是一个烦琐、复杂的过程,临床应该制定个体化的出院计划以及后续随访计划,以提高儿童及其家庭的生活质量,尽可能地延长儿童生命。

长期施用控释尿素对潮土土壤酸碱缓冲体系与土壤肥力的影响

[目的]为探究长期施用控释尿素对北方石灰性潮土土壤酸度、酸碱缓冲能力及肥力的影响。[方法]基于自2008年开始的长期定位小麦玉米轮作施肥试验,设计掺混控释尿素和普通尿素2种氮肥类型及不施氮[N 0 kg/(hm^(2)·a)]、常量[N 540 kg/(hm^(2)·a)]和增量[N 810 kg/(hm^(2)·a)]3个施氮水平,于2022年玉米季成熟期采集0—80 cm土层土壤样品,测定土壤酸碱缓冲容量、土壤碳酸钙含量与土壤养分。[结果](1)控释尿素减缓了因施氮导致的土壤缓冲容量和pH下降,缓解了土壤酸化过程。常量掺混控释尿素、增量掺混控释尿素处理的缓冲容量分别较普通尿素处理常量普通尿素、增量普通尿素升高5.22%和11.17%,常量掺混控释尿素、增量掺混控释尿素处理的pH分别较常量普通尿素、增量普通尿素升高0.17和0.08个单位。(2)控释尿素提高了土壤阳离子交换量与交换性钙镁含量,提高了耕层土壤的活性碳酸钙含量,常量掺混控释尿素和增量掺混控释尿素处理活性碳酸钙含量分别较常量普通尿素和增量普通尿素处理升高52.08%和45.31%。同时,控释尿素减缓了土壤深层次土壤碳酸钙含量损失。(3)控释尿素提高了土壤全氮、有机质、硝态氮和铵态氮含量。[结论]长期施用控释尿素缓解了因施用氮肥导致的土壤酸化,提高了土壤活性碳酸钙含量,提高了土壤肥力。

K439B镍基铸造高温合金800℃长期时效过程中碳化物的演变规律

K439B镍基合金是一种承温能力达800℃的新型铸造高温材料,在发动机机匣类复杂结构件有重要应用前景。作为该合金中的主要晶界强化相,碳化物在合金长期时效过程中的演化规律尚不清楚。以K439B合金为对象,在800℃下对该合金进行了6000~10000 h的等温时效实验,研究了其长期时效过程中碳化物的演变规律和转变机理。结果表明,K439B合金的组织稳定性优异。经过长期时效后,晶界和枝晶间组织中仍保留大部分标准热处理态时的MC型碳化物,仅有部分MC型碳化物分解为M_(23)C_(6)型碳化物和γ′相,未出现η相和σ相等TCP有害相。晶界M_(23)C_(6)型碳化物表现出两种不同的粗化行为,一是M_(23)C_(6)型碳化物逐渐宽化,在长期时效后宽度均一,碳化物排列整齐;二是在某些晶界部位,粗化后的M_(23)C_(6)型碳化物呈现不规则的形状,甚至向晶粒内部延伸。晶界M_(23)C_(6)型碳化物并未出现沿整个晶界的完全相连情况,其主要是γ′相颗粒将两个相邻的M_(23)C_(6)型碳化物分隔所致。

一种可自定义词库的术语录入、查询与标注系统的建立

术语的统一与规范使用在科研论文和学术图书的写作、翻译、编辑、校对以及审阅等过程中具有重要意义。为了在Word本地文档中实现术语快捷录入、模糊查询和免费、批量自动标注,系统利用Excel工作簿存储自定义词库,利用表单控件和VBA代码实现术语录入,利用动态数组函数FILTER实现术语查询,利用VBA代码实现Excel与Word联动并对文档批量添加批注。可以在该系统中实现词库的自主管理,在无须安装其他软件或联网的条件下实现词库便捷录入、术语即时查询和对本地文档进行批量自动标注,适合在写作、翻译、编辑、校对、审阅等多种场景下使用。得益于Excel软件的普及性,该系统具有较强通用性,能够在多种场景下提高术语统一工作的效率。同时文章也指出了系统存在的不足之处。

生物炭基产品及其对土壤培肥改良效应的研究进展

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