两阶段领域自适应学习

针对领域自适应问题中源域和目标域的联合分布差异最小化问题,提出两阶段领域自适应学习方法.在第一阶段考虑样本标签和数据结构的判别信息,通过学习一个共享投影变换,使投影后的共享空间中边缘分布的差异最小.第二阶段利用源域标记数据和目标域非标记数据学习一个带结构风险的自适应分类器,不仅能最小化源域和目标域条件分布差异,还能进一步保持源域和目标域边缘分布的流形一致性.在3个基准数据集上的实验表明,文中方法在平均分类准确率和Kappa系数两项评价指标上均表现较优.     

Attitude-behaviour dissonance regarding the importance of food preservation for customers

The aim of the study was to identify the importance of individual food product attributes (the use of preservatives, processing method, shelf-life period and nutritional value) as well as their relation to the purchase behaviour. To achieve this, consumer preferences were decomposed in conditions of full access to information, and data was compared with actual consumer behaviour related to making purchasing decisions in front of the store shelf. Based on data from 338 respondents, conjoint analysis and repeated ANOVA measurements were carried out, allowing to eliminate individual behavioural patterns. The results showed a dissonance between the consumers attitudes towards the attributes and their shopping behaviour. The processing method was the most important declared attribute for consumers, meanwhile this information was the least searched for during purchase. At the same time, shelf-life period marked as the least important was the main information searched for by consumers when shopping. The results also show a clear dislike towards the use of microwaves as a preservation method, while traditional thermal preservation was marked as the most positive for consumers. In addition, consumers were classified into 3 heterogeneous groups, identifying differences in the preferences of food attributes. The obtained results have practical value relating not only to the preferences of individual attributes, but also to their various variants. The results can be a guide for companies to properly label food products. The indicated dissonance illustrates the educational gap and related insufficient motivation to get to know the product before buying it. This is extremely important in connection with technological development and new food processing methods.     

低温等离子体处理模式对冷藏南美白对虾中假单胞菌的抑菌效果及机理研究

摘 要：目的 探究低温等离子体(cold plasma, CP)处理模式对冷藏南美白对虾中常见荧光假单胞菌(Pseudomonas fluorescens)的抑菌效果及其作用机制。方法 通过CP直接处理和循环处理P. fluorescens,研究了两种处理模式下臭氧含量动态变化对P. fluorescens的生长曲线、细胞活力,生物膜形成、细胞壁、细胞膜完整性和南美白对虾菌落总数及假单胞菌数等指标的影响。结果 两种处理模式在CP处理3 min或3 cycles后,包装内臭氧含量达到最高值,分别为(850±10) mg/m3和(874±20) mg/m3。CP循环处理模式使得臭氧含量随处理循环数递增,因此获得更长的臭氧存在时间从而具有更大的抑菌能力。P. fluorescens生长曲线表明CP处理使得菌体延迟期变长且对数生长期推迟。此外,CP处理后的P. fluorescens细胞活力显著下降(P<0.05),CP-1 min,CP-3 min和CP-3 cycles组的细胞活力分别为33.03%、5.90%和4.82%。同时相比CP-3 min组,CP-3 cycles组的P. fluorescens生物膜OD值下降27.61%。碱性磷酸酶(alkaline phosphatase, AKP)活性和核酸蛋白泄漏量结果表明,细胞壁和细胞膜完整性受损可能是P. fluorescens失活的直接原因。对虾保鲜测试结果证实,贮藏第6 d,CP-3 cycles组虾体中的菌落总数和假单胞菌数相比CP-3 min组分别降低了58.02%和79.54%。结论 CP循环处理模式通过延长对臭氧与对虾的暴露时间,提高了对P. fluorescens的灭活效果,同时还具有更优越的保鲜能力。本研究为开发基于CP技术的新型保鲜技术应用提供了理论参考。 关键词：低温等离子体;荧光假单胞菌;抑菌机制;保鲜     

四川盆地东南地区龙马溪组页岩气有效保存区综合评价

受差异构造边界的制约,四川盆地东南地区(简称川东南)中新生代发生差异构造变形,使得保存条件成为控制该区下古生界页岩气富集的主要因素。为此,从制约保存条件的直接原因——构造作用出发,对该区页岩气保存条件进行了综合评价。首先以构造研究为先导,立足于中新生代差异构造变形方式和强度,将评价区划分为7个构造形变带,并对各构造形变带的断裂规模、断裂密度、顶底板岩性和厚度、目的层埋深、构造形态和裂缝间距指数等影响因素进行系统揭示,确立页岩气有效保存区的评价指标和标准,建立页岩气保存条件综合评价体系。在此基础上,依据该区页岩气保存条件最优评价参数标准,对7个构造形变带下志留统龙马溪组页岩气的保存条件进行了宏观评价。结果表明:齐岳山断裂以西地区的保存条件整体上好于东侧;齐岳山断裂以东地区,以武隆断褶带的保存条件为最好,其次为彭水断褶带和黔江断褶带,道真叠加断褶带、务川叠加断褶带和沿河叠加断褶带相对较差。     

Impact of whole-building hygrothermal modelling on the assessment of indoor climate in a library building

This paper focuses on the importance of accurately modelling the hygrothermal interaction between the building and its hygroscopic content for the assessment of the indoor climate. Libraries contain a large amount of stored books which require a stable relative humidity to guarantee their preservation. On the other hand, visitors and staff must be comfortable with the indoor climate.     

Some Ozone Applications in Seafood

The use of ozonized seawater to reduce and eliminate bacterial pathogens in mariculture facilities and to extend shelf life of marine food products is demonstrated. Consequent benefits of this treatment are also discussed. Laboratory and pilot experiments were conducted using ozone gas to reduce disease-producing Vibrio sp. bacteria at a shrimp (Litopenaeus vannameii) hatchery in Ecuador, South America. Pacific Ocean seawater was treated in a 1,540 L capacity fiberglass contact tower (5–7 min retention) with an ozone oxidant residual of 0.07 mg/L. Prior to ozone treatment, Vibrio determined by TCBS plating was too numerous to count, causing shrimp to die of disease (30 tanks of 13,000 L each). After treatment, Vibrio counts and shrimp disease were eliminated, ozonized seawater decreased the time required for normal molting of shrimp and the total growth cycle was reduced by three days versus control water. From June 1991 until September 1992, survival rates of larval shrimp were robust, routine antibiotic addition was reduced, and one additional growth cycle was realized. Ozonized ice (fresh water) was prepared in the Milford Laboratory CT, USA; Gloucester Food Tech Lab, MA, USA; and a field station (brine water) for sockeye salmon (Oncorhynchus nerka) in Homer, AK. USA. In these studies, squid (Loligo pealei) and commercially captured salmon demonstrated a reduction in spoilage and extension of shelf life of 3 to 5 days' time using ozonized ice. Bacteria associated with commercial ice-producing machines were reduced by 4 logs using ozone treatment. In addition, no flavor aberration was noted using ozonized ice.     

PANIC: an integrated approach to the preservation of composite digital objects using Semantic Web services

To date, long-term preservation approaches have comprised of emulation, migration, normalization, and metadata – or some combination of these. Most existing work has focussed on applying these approaches to digital objects of a singular media type: text, HTML, images, video or audio. In this paper, we consider the preservation of composite, mixed-media digital objects, a rapidly growing class of resources. We describe an integrated, flexible system that we have developed, which leverages existing tools and services and assists organizations to dynamically discover the optimum preservation strategy as it is required. The system captures and periodically compares preservation metadata with software and format registries to determine those objects (or sub-objects) at risk. By making preservation software modules available as Web services and describing them semantically using a machine-processable ontology (OWL-S), the most appropriate preservation service(s) for each object (or sub-object) can then be dynamically discovered, composed and invoked by software agents (with optional human input at critical decision-making steps). The PANIC system successfully illustrates how the growing array of available preservation tools and services can be integrated to provide a sustainable, collaborative solution to the long-term preservation of large-scale collections of complex digital objects.     

松辽盆地岩性圈闭形成机理及识别方法

改变了把地层划分为储层和封盖层识别岩性圈闭分布的传统方法,将其划分为储集层、非储输导层和封堵层３种不同性质地层,３种地层的空间展布决定了岩性圈闭的构成与分布。而岩性圈闭的可靠性决定于封堵层界面和储集层界面的匹配关系。在总结多年来松辽盆地岩性圈闭（带）各种识别方法的基础上,根据岩性圈闭构成新理论,提出了岩性圈闭的双界面识别法。     

历史建筑的空间信息采集——三维激光扫描技术应用

本文介绍了三维激光扫描技术应用于历史建筑现状空间信息采集方面的研究和实验。