纺织专家系统中知识与知识库的应用

专家系统是人工智能的一个分支，是一种模拟专家决策能力的计算机系统，知识库是系统的重要组成部分，是系统的核心。本文结合纺织工艺设计及管理专家系统介绍了基于知识的专家系统的概念和结构，对系统中知识的获取、存储方式予以说明．并对其知识的表示方法加以阐述。     

Computerized container-ship load planning: A methodology and evaluation

A heuristic is developed to plan loads for containerized cargo ships. It is designed to serve a port which uses gantry cranes (transtainers) and trucks to handle containers. The model recognizes constraints on ship stability, placing containers in a bay with the proper length, limits on stack height in under-deck bays, limits on stack weight in on-deck bays, refrigerated containers, and the need for support under a container. Provisions are made for the operator to handle overstowage of cargo for different ports and placement of oversize cargo. The model uses minimization of transtainer movement time and minimization of rehandles in the yard as an objective. The heuristic uses strategies for container placement similar to those used in manual load planning. A test of two ships and four voyages at the Port of Portland produced feasible load plans for each voyage. Transtainer movement and rehandling time varied for the four voyages; but on the average, the heuristic reduced a composite material handling measure by 4.8%.     

The coxsackievirus-adenovirus receptor protein can function as a cellular attachment protein for adenovirus serotypes from subgroups A, C, D, E, and F

Attachment of an adenovirus (Ad) to a cell is mediated by the capsid fiber protein. To date, only the cellular fiber receptor for subgroup C serotypes 2 and 5, the so-called coxsackievirus-adenovirus receptor (CAR) protein, has been identified and cloned. Previous data suggested that the fiber of the subgroup D serotype Ad9 also recognizes CAR, since Ad9 and Ad2 fiber knobs cross-blocked each other's cellular binding. Recombinant fiber knobs and 3H-labeled Ad virions from serotypes representing all six subgroups (A to F) were used to determine whether the knobs cross-blocked the binding of virions from different subgroups. With the exception of subgroup B, all subgroup representatives cross-competed, suggesting that they use CAR as a cellular fiber receptor as well. This result was confirmed by showing that CAR, produced in a soluble recombinant form (sCAR), bound to nitrocellulose-immobilized virions from the different subgroups except subgroup B. Similar results were found for blotted fiber knob proteins. The subgroup F virus Ad41 has both short and long fibers, but only the long fiber bound sCAR. The sCAR protein blocked the attachment of all virus serotypes that bound CAR. Moreover, CHO cells expressing human CAR, in contrast to untransformed CHO cells, all specifically bound the sCAR-binding serotypes. We conclude therefore that Ad serotypes from subgroups A, C, D, E, and F all use CAR as a cellular fiber receptor.     

VHF propagation characterization during atmospheric disturbances

Abstract

The propagation of a television (TV) signal is usually perturbed during periods of atmospheric disturbance such as in thunderstorms. The region under investigation here is situated in the coastal area of the Bay of Bengal and has experienced frequent thunderstorm activities. An investigation to study their effects on VHF signal propagation transmitted from Satkhira in Bangladesh and received at the Indian Statistical Institute, Calcutta, has been undertaken. The depths of the atmospheric disturbances within a 1?km range have been recorded and measured by acoustic sounder (sodar) operated continuously at the receiving station. The inset of the storm is marked by the enhanced signal level with deep fluctuations characteristic during the periods of thunderstorms.     

Analysis of hexamidine, dibromohexamidine, dibromopropamidine and chlorhexidine in cosmetic products by high-performance liquid chromatography

A method of determining qualitatively and quantitatively hexamidine, dibromohexamidine, dibromopropamidine and chlorhexidine in cosmetic products by means of paired ion, reverse-phase high-performance liquid chromatography (HPLC) and ultraviolet detection (UV) at 264 nm.
Détermination de l'hexamidine, du dibromohexamidine, du dibromopropamidine et de la chlorhexidine dans les produits cosmétiques     

大青叶抗菌物质提取及抗菌效果研究

研究了用水浸提法抽提大青叶中抗菌物质的方法，并通过抑菌实验检验了对细菌和霉菌的抑菌能力。正交实验结果表明最佳抽提工艺为：料水比1：20，加热时间40min，回流温度100℃：滤纸片法抑菌实验发现：大青叶提抽浓缩液(浓缩比为5：1)对大肠杆菌及枯草杆菌的最低抑菌浓度为2．77％(ml，100ml)左右，青霉，黄曲霉为0．55％(ml／100ml)左右，金黄色葡萄球为0．055％(ml／100ml)左右。     

PROTEIN-PHYTATE INTERACTIONS IN SOYBEANS. II. MECHANISM OF PROTEIN-PHYTATE BINDING AS AFFECTED BY CALCIUM

Phytate and bovine serum albumin were used in a model system to investigate the mechanism of their binding. Ultrafiltration studies using response surface design showed the association of protein and phytic acid to be highly pH dependent. Under acid conditions, the protein formed an insoluble complex with phytic acid. At pH 3.0, a binding constant of 2.3 times 10⁵ was obtained and it was calculated that there are 78 binding sites of the total 93 basic amino acid residues potentially available. This low pH complex was not disrupted at high temperatures but the presence of calcium ions caused dissolution of the precipitate. Calcium produced different effects at higher pH (> 6). Soluble protein-calcium-phytic acid complexes were formed which were less stable to heat and dissociated above pH 10 at high ionic strength. Since this interaction occurred only in the presence of calcium, a salt linkage is implicated in which divalent cations simultaneously bind to the protein and phytic acid in the form of a soluble complex. It is proposed that either the addition of divalent cations at low pH or sequestering agents at high pH would best effect the removal of phytate from soy products by ultrafiltration.     

Growth and reproduction characteristics of purebred and crossbred dairy cattle in first lactation

Breed additive, maternal, and heterozygotic effects on 11 monthly postpartum body weights, average size, weight gain, age at first calving, and days open were estimated by linear regression analyses from records of 680 purebred and crossbred animals. Calving year, age, and milk yield were significant environmental effects. Positive regressions of age on body weights indicated late calving cows were heaviest postpartum and had most days open. Negative regressions of milk yield on weight gain and postpartum weight showed greatest losses of weight associated with highest yields. There were breed differences in growth; purebreds highest to lowest were Brown Swiss, Holstein, Red Dane, Jersey, and Ayrshire and for weight gain, Brown Swiss, Ayrshire, and for weight gain, Brown Swiss, Ayrshire, Jersey, Holsteins, and Red Dane. Crosses were superior to purebreds in these traits. Additive effects of Holstein were greater than Ayrshire, Jersey, and Red Dane for postpartum body weights and average size. All constants for heterozygotic effect combinations were significant for postpartum weights and average size. Heterozygosity effects increased in magnitude with advancing lactation. Generally, age at first calving and postpartum interval to conception reflected little heterozygotic or maternal effects. There was some indication of breed differences in mean and additive effects for age at first calving.     

MULTIRESPONSE OPTIMIZATION of ACID CASEIN PRODUCTION

A multivariate skimmilk extrusion process, designed to produce an acid coprecipitate was studied in terms of minimizing residual lactose, ash and fines. an experimental model system was utilized to simulate the extrusion process and evaluated using response surface methodology to assess the relationship between the responses (fines, residual lactose and minerals) and the process variables (concentration, pH, temperature, agitation, washing time and wash water ratio). Compromise optimum conditions were derived using the Generalized Distance Approach (GDA) and an Extended Response Surface Procedure (ERSP) which made use of the SAS RSREG procedure with and without constraints. the GDA procedure produced good results in terms of providing an optimum for a general acid casein process, while the ERSP allowed more extensive analysis of the data in terms of assessing specific processing conditions. Although more computing intensive, the ERSP conferred additional flexibility in determining optimal conditions for special situations such as extrusion processing. Both approaches are useful for process engineering, with the GDA being a more general tool while the ERSP is advantageous when the GDA procedure becomes limiting.