Hydrodynamic and towing characteristics of a modified model of the Clarke Jet Net

In a series of studies to develop an effective high speed plankton sampler, hydrodynamic research was carried out on a modified model of the Clarke Jet Net. A theoretical analysis of the motion of the sampler was made using an IBM 7040 computer, and test tows were made in an experimental ship tank and at sea. To maintain the roll angle of the sampler at approximately zero, a v-shape bridle was applied. A pair of towing holes should be selected for the particular range of towing velocity. The calculated longitudinal stability seemed good in all the cases examined. Towing tests in the ship tank at 2 to 3 m/sec revealed sufficient stability. The motion of the sampler at speeds higher than 3 m/sec can be assumed from hydrodynamic coefficients derived from the ship tank experiment. Towing-cable characteristics, assumed by computation, indicated that about 500 m at 6 kt and 1,000 m at 12 kt should be paid out to lower the sampler down to 100 m. The effect of the sampler on the cable is found only adjacent to it and is almost negligible beyond 50 m from it in depth. Results of sea tests at 6 and 9 kt confirmed the stability of the sampler. Examination of the catch suggested that the present model can be used, with some modifications, for the quantitative and qualitative sampling of large zooplankton.Contribution No. 231 from the Seikai Regional Fisheries Research Laboratory, Nagasaki.     

Classification of juvenile rockfish,<Emphasis Type="Italic"> Sebastes inermis</Emphasis>, to<Emphasis Type="Italic"> Zostera</Emphasis> and<Emphasis Type="Italic"> Sargassum</Emphasis> beds,using the macrostructure and chemistry of otoliths

Young-of-the-year (YOY) Sebastes inermis use Zostera and Sargassum beds as nursery grounds, although it is not known which habitat YOY prefer. In this study, YOY S. inermis were accurately assigned to Zostera or Sargassum beds by two approaches: the width and length of the otolith nucleus and the composition of trace elements in otoliths. The otolith nucleus was initially opaque and then showed a marked shift to hyaline deposition once YOY settled in the nursery grounds. The first hyaline zone (FHZ) was deposited earlier in Zostera beds (from mid-May to early June) than in Sargassum beds (around mid-summer). Likewise, irrespective of settlement year, the FHZ was formed at both significantly younger ages and shorter back-calculated sizes (total length, TL) in the Zostera bed (overall mean: 131±3 days; 2.5±1.7 mm TL) than in the Sargassum bed (overall mean: 158±12 days; 61.3±1.00 mm TL). YOY collected in the Zostera bed were born earlier (mainly in January) than YOY from the Sargassum bed (mainly in February). In addition, a significant linear relationship was found between the age at formation of the FHZ and nucleus dimensions, suggesting that nucleus dimensions were a reliable macroscopic indicator of the time of formation of the FHZ and, consequently, also an indicator of the nursery where YOY grew. Linear discriminant function analysis (LDFA) based on the width and length of the otolith nucleus could distinguish juveniles from Zostera (88–96%) and Sargassum (96–97%) beds with a high degree of accuracy. In the other approach, six detectable trace elements (Li, Mn, Ni, Cu, Zn, and Ba) in otoliths of YOY collected in the nursery grounds were measured by high-resolution, inductively coupled mass spectrometry. LDFA based on the trace elemental composition separated YOY from three nurseries with 100% of accuracy. Findings suggest that both the trace elemental composition and nucleus dimensions of otoliths can be used as natural tags of the nursery grounds of S. inermis, offering a considerable potential for answering questions on habitat use and the contribution of nursery grounds to the adult stock.Communicated by T. Ikeda, Hakodate     

一种基于小样本数据信息扩散的重大火灾频度估算方法

重大火灾的发生是小概率事件,其历史数据属于小样本统计数据。在应用频率直方图法对小样本数据进行处理时,分析结果对直方图的起点、区间步长以及样本中的奇异数据十分敏感。采用信息扩散方法,对日本1995-2008年各年重大火灾次数统计样本进行分析,对比了不同扩散条件下的扩散结果,结果表明信息扩散方法具有很好的稳定性和一致性。基于信息扩散的结果,计算了以年为周期的重大火灾发生次数的超越概率分布,建立了一种重大火灾频度估算方法。     

Integrated model of reaction rate equations and thermal energy balance in aerobic bioreactor for food waste decomposition

The integrated model is composed of two basic parts: one is a reaction rate model of biodegradation in combination with bioenergetics and the other is a thermal engineering model of energy flow and balance in the bioreactor. Integrating these models provides possibility to estimate microbial activity using time course of physicochemical parameters such as bed temperature, bed weight, and/or C0₂ concentration during decomposition.     

GIS支持下的滑坡空间预测与危险等级划分

以日本早池峰山地域为研究对象,借助航片、TM影像、数字化地图以及各种统计资料和现有专题图等主要数据,利用美国MicroImage公司开发的TNTmips地理信息系统,将数量化理论与地理信息系统紧密结合,对区域滑坡进行了空间预测和危险等级划分.提取并计算了滑坡以及包括坡度、坡向、海拔、坡面倾斜类型、降雨、植被、土壤和地质等8个滑坡影响因子,得到了滑坡及其影响因子的空间分布图.在此基础上,抽取372个样本,应用数量化理论对这些样本进行了分析,建立了区域滑坡预测模型.该模型经研究区域共1296384个样本检验,模型预测精度达80.49%.最后,以滑坡发生概率为基准,对滑坡危险等级进行了划分.     

Climatic and Environmental Changes in the Source Areas of Dust Storms in Xinjiang, China, during the Last 50 Years

The desert environmental changes in the source areas of dust storms occurring in Xinjiang are discussed based on the climate changes and the impacts of human activities in Xinjiang during the past 50 years. The results show that the climate in Xinjiang is changing from a warm-dry type to a warm-wet one. The warm-wet climate has been obvious since the mid-1970's, and especially the sensitivity of the regional climate change in this arid area is obviously revealed by many factors, such as the characteristics of the local climate change in south Xinjiang and north Xinjiang, the difference of climate change in the alpine zones and the basins, and the change of areas of the waters bodies. Furthermore, these factors also reveal the difference in the regional climate change between Xinjiang and central and eastern areas of China. The occurrence and development of dust storms are directly affected by the precipitation, air humidity, status of underlying surface, etc. in the arid areas. The frequency and intensity of dust storms are closely related to the natural conditions, changes of climate and desert environment, as well as the dynamic conditions (i.e., weather systems) in the source areas of dust storms. Therefore, global warming is one of the main causes resulting in the degradation of the ecological environment and the frequent occurrence of natural disasters, especially the disasters of sand drift and dust storms in the arid areas since the late-1980's, which reveals that the inland arid areas are sensitive regions to climate changes.     

Evaluation of current material stock and future demolition waste for urban residential buildings in Jakarta and Bandung,Indonesia: embodied energy and CO<Subscript>2</Subscript> emission analysis

First, this paper evaluates the current building material stock and future demolition waste for urban residential buildings in the cities of Jakarta and Bandung using a material-flow analysis. The actual on-site building measurements were conducted in Jakarta (2012) and Bandung (2011), focusing particularly on unplanned houses, to obtain building material inventory data. A total of 297 houses were investigated in Jakarta, whereas 247 houses were measured in Bandung. Second, this paper analyses the embodied energy and CO₂ emissions of building materials through an input–output analysis. The results show that, overall, the total material input intensity for the houses is 2.67 ton/m² in Jakarta and 2.54 ton/m² in Bandung. Two scenarios with zero and maximum reuse/recycling rates were designed to predict future demolition waste and the embodied energy/CO₂ emissions of building materials in Jakarta. Closed- and open-loop material flows were applied. If the maximum reuse/recycling rates are applied to the closed- and open-loop material flows in Jakarta, then it would become possible to not only decrease the final disposal waste (from 123.9 to 2.1 million ton) but also reduce the corresponding embodied energy (from 247.8 to 192.1 PJ) and CO₂ emissions (from 24.3 to 19.2 million ton CO₂-eq) compared with the zero reuse/recycling scenario from 2012 to 2020.     

Toward knowledge structuring of sustainability science based on ontology engineering

In sustainability science (SS), it is difficult to identify what needs to be solved, and it is also not clear how to solve the problems that are identified. There has been no consensus on the underlying question of “What is structuring knowledge in SS?” This paper focuses on knowledge structuring accompanied by supporting of thinking. It addresses the key challenges associated with knowledge structuring in SS, identifies the requirements for the structuring of knowledge, proposes a reference model, and develops an ontology-based mapping tool as a solution to one layer of the reference model. First, we identify the important requirements for SS knowledge structuring. Second, we develop a reference model composed of five layers based on three of the requirements. Third, we develop an ontology-based mapping tool at Layer 2 of the reference model for meeting the two major challenges for SS, namely, identifying what problems should be addressed in SS itself and proposing solutions for those problems. The tool is designed to store and retrieve information regarding SS, to provide access to a prototype ontology for SS, and to create multiple maps of conceptual chains depending on a user’s interests and perspectives. Finally, we assess whether the developed tool successfully realizes the targeted part of the reference model for SS by examining the tool’s conformity to the reference model, as well as its usability, effectiveness, and constraints. Although several issues were identified in the prototype ontology and the mapping tool, the study concluded that the mapping tool is useful enough to facilitate the function of Layer 2. In particular, the mapping tool can support thinking about SS from the viewpoint of: (a) finding new potentials and risks of technological countermeasures studied in SS; (b) helping users to get a more comprehensive picture of problems and their potential solutions; and (c) providing an effective opportunity to come up with new ideas that might not be thought of without such a tool.