Assessment on Energy Self-Sufficiency Rate for Building Integrated Photovoltaics and Fuel Cell System in Japan

A building integrated photovoltaic (PV) and fuel cell (FC) system is proposed for assessment of the energy self-sufficiency rate in a city in Japan. The electricity consumed in the building is mainly supplied by solar panels, while the gap between the energy demand and supply is solved by the FC that is powered by the H2 produced by water electrolysis with surplus power of PV. A desktop case study of using the proposed system in Tsu city which is located in central part of Japan, has been conducted. The results found that the self-sufficiency rates of PV system to electricity demand of households (RPV) during the daytime in April and July are higher than those in January and October. The results also reveal that the self-sufficiency rate of FC system to the electricity demand (RFC) is 15% - 38% for the day when the mean amount of horizontal solar radiation is obtained in January, April, July and October. In addition, it is found the optimum tilt angle of solar panel installed on the roof of the buildings should be 0 degree, i.e., placed horizontally.

ROLE OF REMOTE SENSING IN ACHIEVING NATIONAL FOOD SELF-SUFFICIENCY AND FOOD SECURITY

This paper seeks to explore the role of Remote Sensing in solving the agriculture related problems, which are the basic issues of sustainable development.

China’s Food Security Status:Assessment and Strategic Reflections

Based on an internationally recognized concept of food security, this paper has created a system of eight indicators to analyze China＇s food security. For the proper control and analysis of this study, the authors of this paper have chosen these indicators： supply, distribution, consumption, utilization efficiency, food security results, stability, sustainability and controllability. Results indicate that China＇s food security is currently at a high level and has been increasing in recent years. China＇s food security has multiple advantages with various indicators that include a self-sufficiency ratio, per capita calorie intake and protein supply that are above world average levels, even exceeding the average level of some developed countries. Major challenges facing China＇s food security include an unreasonable nutrition structure and poor environmental sustainability. In order to increase China＇s food security level, efforts must be made to adjust output structure, adopt an environmentally friendly pattern of production, attach importance to demand management, reduce unreasonable consumption and loss and moderately lower China＇s food reserve ratio.

Sharp Decline in the Food Self-sufficiency Ratio in Japan and Its Future Prospects

Most Japanese are enjoying rich and convenient dietary habits nowadays. However, majorities of Japanese are feeling anxiety about the future food supply because Japan＇s food self-sufficiency ratio has fallen most rapidly in the last 45 years, and is lowest amongst countries with a population of more than 100 million. Major causes and mechanisms of the decline in the food self-sufficiency ratio over the last 45 years were analyzed. Drastic changes of dietary habits under rapid economic growth and sharp appreciation of the yen against the US dollar were found to be the major causes of the sharp decline of the food self-sufficiency ratio. Preliminary projections about the food self-sufficiency ratio in 2015 were carried out, and it was found that it will not be easy to achieve the policy goal of raising the food self-sufficiency ratio to 45% by 2015.

A Quantitative Factorial Component Analysis to Investigate the Recent Changes of Japan’s Weight-Based Food Self-Sufficiency Ratio

We investigate the weight-based food self-sufficiency ratio (WSSR) for Japan over a 50-year period (1961-2011) by applying factorial component analysis technique in order to measure the changes of the WSSR quantitatively. Quantitative data analysis is employed to determine the drivers of those changes. Numerical results show that Japan experienced a drastic decline in its food self-sufficiency ratio (FSSR) during the above period. The factorial component analysis shows that such a decline was caused by the changes in the FSSR of the food groups/items, not in the quantity of the food supply. A number of characteristics of those changes are presented and a list of major food groups that have major impacts on the changes is constructed. The findings in this paper reiterate the alarming food security problem in Japan and provide clear insight into the causes of this problem. The findings in this study pick up where previous studies have left off, aid the food-related policy-making process and identify new ideas for future food research.

Food intake rate and delivery strategy in aquaculture

In aquaculture,it is important to estimate in advance how much food cultured animals would take.The rate of food consumption by cultured animals to available food amount is defined as the food intake rate(FIR) in this paper.To some extents,FIR reflects the quality of food,the health of cultured animals and the delivery efficiency.In practice,it is difficult to estimate in advance the accurate quantity of food that cultured animal needs.Usually,food is provided more than the need by animals,causing excess food that may pollute water and environment.Our experiments in past years show that FIR at 80% is recommended.

Empirical Analysis of Agricultural Policy Impacts of Senegal for food Self-sufficiency： The Stochastic Frontier Production of Rice and Maize in Senegal River Valley

The stochastic production function estimates of rice and maize in Senegal River Valley demonstrate the possibility to reach self-sufficiency of rice in Senegal. Nonetheless, its fulfillment requires many accompanying measures in rice and maize production. These measures include all upstream and downstream activities related to agricultural production for their efficiency and sustainability in rice and maize production to maintain the country＇s comparative advantages and competitiveness. Then priorities should be given to agricultural infrastructure building, establishment of credit markets, and providing an easy access of production factors （e.g., improved land, fertilizers, improved and certified seeds, as well as agricultural machines）. Furthermore, policy makers should provide a larger incentive in terms of producer price to encourage farmers to increase considerably their outputs, thereby farmers face smaller risk of having non-sold outputs. And during an early harvesting period, appropriate policy measures are in need to prevent farmers from dumping their products under severe social and economic pressures such as children schooling and loan payment, etc

Variation in the emission rate of sounds in a captive group of false killer whales Pseudorca crassidens during feedings: possible food anticipatory vocal activity?

This study examines whether a group of captive false killer whales(P seudorca crassidens) showed variations in the vocal rate around feeding times. The high level of motivation to express appetitive behaviors in captive animals may lead them to respond with changes of the behavioral activities during the time prior to food deliveries which are referred to as food anticipatory activity. False killer whales at Qingdao Polar Ocean World(Qingdao, China) showed signifi cant variations of the rates of both the total sounds and sound classes(whistles, clicks, and burst pulses) around feedings. Precisely, from the Transition interval that recorded the lowest vocalization rate(3.40 s/m/d), the whales increased their acoustic emissions upon trainers' arrival(13.08 s/m/d). The high rate was maintained or intensifi ed throughout the food delivery(25.12 s/m/d), and then reduced immediately after the animals were fed(9.91 s/m/d). These changes in the false killer whales sound production rates around feeding times supports the hypothesis of the presence of a food anticipatory vocal activity. Although sound rates may not give detailed information regarding referential aspects of the animal communication it might still shed light about the arousal levels of the individuals during different social or environmental conditions. Further experiments should be performed to assess if variations of the time of feeding routines may affect the vocal activity of cetaceans in captivity as well as their welfare.

大食物观下基于营养平衡的食物自给率测算与食物安全保障策略

中国食物消费经历快速转型升级,食物安全也延拓到数量、质量、营养等层面。食物自给率是食物安全的核心衡量指标,本文以大食物观为指引,多视角分析中国食物与营养自给率变化趋势,并以营养平衡膳食为目标测算主要食物自给率变化。结果显示,2010—2022年奶类、豆类和谷类下降最快,蛋白质和碳水化合物的降幅大于热量的降幅。通过测算平衡膳食目标下食物自给率发现,谷物和肉类趋于上升,奶类降幅最大。与其他国家相比,中国营养总量供应能力处于中等偏上水平,但从结构上看植物类食物占主要比例,豆类和高蛋白肉类自给比例远低于发达国家。未来需要推进以营养健康为导向的结构性改革,积极达成供需结构与质量的动态平衡,以期实现中国高质量、可持续的食物安全。

陕西省粮食安全水平评价及预测研究

【目的】为解决陕西省粮食供需日益突出的矛盾找出对策。【方法】在分析陕西省人口变动及粮食供需现状的基础上,通过计算2004—2020年陕西省耕地赤字率,对当前陕西省粮食安全水平进行评价。在此基础上,运用灰色预测模型GM(1,1)对未来10 a陕西省粮食安全水平进行预测。【结果】随着人均粮食消费量的增长,陕西省耕地赤字率持续增长;未来10 a陕西省粮食供需剪刀差不断扩大。【结论】加强耕地保护力度,优化土地资源利用;强化农业科技创新;稳定粮食价格;完善粮食储备体系有利于改善陕西省粮食供需矛盾日益突出的问题,保障粮食安全。

菌剂添加条件下通风量对食品废弃物好氧发酵过程的影响

通风量是影响食品废弃物好氧发酵产物质量且关系过程成败的重要制约因素。本文通过调整发酵过程中的通风量,控制食品废弃物中油脂的降解与有机酸的产生和累积,实现发酵过程的有限酸化,不仅可减少NH_(3)挥发与流失,还可提高发酵产物的质量。研究结果表明,随着通风量增大,发酵物料的峰温度升高,但高温期缩短,有机质降解率和腐熟度先升高后降低,当通风量为0.2L/(L·min)时,发酵效果较佳。通风量越大,NH_(3)累积挥发量越低。通风量为0.1L/(L·min)时,高温期较长,不利于硝化微生物的生长繁殖,NH_(3)排放量最大。通风量为0.3L/(L·min)时,高温期最短,同时水分散失严重,有机物降解不彻底,NH_(3)挥发量也最低。与未添加自制除油微生物菌剂(ORMI)相比,接种ORMI可以有效促进食品废弃物好氧发酵的效果,发酵结束时,油脂降解率、种子发芽指数和总养分含量分别提高了23.08%、29.48%和7.36%。通风量通过影响相关微生物活性及脂肪酶酶活促进油脂降解,减少氨的累积挥发量,最终有效提升发酵产物的腐熟度和总养分含量。

“数字泰勒主义”影响下的外卖平台“计件工资制”研究

对工业生产中“计件工资制”的研究表明,薪酬制度不仅从经济维度影响劳动者的行为,更是形塑劳动者从纯劳动力意识向纯劳动意识转变的重要机制,是劳动力过度商品化的重要基础。本文通过对外卖平台“计件制”中的派单、奖励、惩罚等规则的梳理,提出平台“计件工资制”虽然在形式上承继了工业生产“计件制”“多劳多得”的简单累积逻辑,但根本上已经变成了高投入、高回报和高风险的企业家式博弈,以及本质上的加速积累逻辑。同时,通过对骑手个体经营意识、过渡意识、自由意识、平等意识等被薪酬制度所形塑的企业家式劳动主观意识的呈现,进一步提出外卖平台薪酬制度的变迁意味着平台劳动中的“数字泰勒主义”并非工业劳动经典“泰勒制”的自然延续,而是具备了主客观方面的独特特征。

龄期、食料和密度对小地老虎幼虫自残的影响

小地老虎是农林作物苗期的重要地下害虫,自残行为影响其种群消长,对理清其种群动态规律和预测防治具有重要意义。本研究通过室内建立玉米、小白菜、烟草和人工饲料种群小地老虎,测定龄期、食料和密度对幼虫自残的影响,旨在明确小地老虎的自残特性。结果表明,龄期、食料和密度均对小地老虎幼虫校正自残率有显著影响。其中,4个种群同龄期间的校正自残率最高均为5龄,最低均为2龄;不同种群间的自残程度依次为人工饲料种群>小白菜种群>玉米种群>烟草种群;30头/瓶的饲养密度校正自残率最高。不同龄期混合后各种群均显示2龄幼虫被高龄幼虫残杀概率最高,5龄幼虫最低。不同种群的5龄幼虫混合后玉米种群的被残杀率最高,人工饲料种群的较低。龄期、食料和密度对幼虫校正自残率变异均具有显著影响,其中龄期影响最大(26.80%),食料影响最小(4.40%);龄期对幼虫被残杀率变异具有显著影响,解释11%的变异量。

餐厨垃圾厌氧消化快速启动特性的研究

为明确餐厨垃圾快速启动过程的厌氧消化特性,通过半连续搅拌反应器系统,监测了有机负荷(Organic Loading Rate,OLR)为1.5、2.0、2.5和3.0 gVS·L^(-1)d^(-1)运行过程中沼气产量和甲烷含量、沼液pH值、挥发性脂肪酸(VFA)、碱度和氨氮等参数的变化情况。研究结果表明:OLR从1.5 gVS·L^(-1)d^(-1)提高至3.0 gVS·L^(-1)d^(-1)时,容积产气率提高到2.12±0.05 L·L^(-1)d^(-1),比甲烷产量稳定在273.2±7.8 mLCH_(4)·g^(-1)VS,系统产气性能良好且稳定;挥发性脂肪酸浓度维持较低水平(650 mg·L^(-1)左右),主要成分是乙酸。氨氮含量随着OLR的提升不断增加,最高达到4171 mg·L^(-1),游离氨增加至300~350 mg·L^(-1),对产气性能产生轻微抑制作用;微生物群落分析表明厌氧消化过程主要细菌菌群是Firmicutes、Bacteroidota和Synergistota,优势产甲烷菌群主要以Methanosarcina、Methanobacterium和Methanosaeta为主。厌氧消化启动阶段在有机负荷达到3.0 gVS·L^(-1)d^(-1)时可以稳定运行,反应器成功启动。

复合植物菌剂对断奶仔猪生长指标、血液免疫指标及粪便微生物的影响

以益生菌复配药食同源植物制备的复合植物菌剂为无抗饲料添加剂,研究基础饲粮中添加复合植物菌剂对断奶仔猪生长性能、腹泻率、血液免疫指标及粪便微生物的影响,旨在评估复合植物菌剂作为饲料添加剂的效果。选取24日龄的断奶仔猪54头,随机分为3组:分别饲喂基础饲粮(空白组)、基础饲粮+50 g/t金霉素(对照组)、基础饲粮+0.2%复合植物菌剂(试验组),其中每组设3个重复,每个重复6头仔猪,预试期3 d,正式试验期30 d。结果显示,与对照组相比,试验组断奶仔猪的末质量、平均日增量和头均耗料量显著升高(P<0.05),发病率和腹泻率降低约50%(P<0.05);血液生化指标中,总蛋白、白蛋白、谷草转氨酶和葡萄糖含量显著升高(P<0.05),尿素氮和甘油三酯含量显著降低(P<0.05);IgG、IgM和IgA含量显著增加(P<0.05);粪便中大肠杆菌数量显著降低(P<0.05),乳酸菌和双歧杆菌数量显著升高(P<0.05)。综上所述,在基础饲粮中添加0.2%复合植物菌剂可以显著改善断奶仔猪的生长性能,降低腹泻率,提高血液免疫指标,促进肠道有益菌的增殖。

利用新型红酵母苯丙氨酸解氨酶制备低苯丙氨酸酪蛋白

【目的】挖掘高活性、高稳定性的苯丙氨酸解氨酶(EC 4.3.1.24;penylalanine ammonia-lyase,PAL),为后续在制备无(低)苯丙氨酸特膳食品的应用奠定基础。【方法】从胶红酵母(Rhodotorula mucilaginosa)和双倒卵形红酵母(Rhodotorula diobovata)中克隆到基因RmPAL和RdPAL,并通过生物信息学分析两个酶的序列和结构特征;在大肠杆菌中异源表达纯化RmPAL和RdPAL蛋白,测定最适反应条件和底物特异性;通过高效液相色谱和苯丙氨酸试剂盒测定了RmPAL和RdPAL转化酸解酪蛋白(casein acid hydrolysate,CAH)中苯丙氨酸(L-phenylalanine,L-Phe)的能力。【结果】RmPAL和RdPAL是真菌来源的PAL,分别由3个结构域组成:MIO结构域(MIO domain)、核心结构域(core domain)和屏蔽结构域(shielding domain),活性中心具有催化氨基酸Tyr和底物特异性特征氨基酸His;RmPAL和RdPAL在溶液中均以四聚体形式存在,两个酶的最适pH和最适温度均为8.9和50℃,且具有较宽泛的pH和温度稳定性,优于黏红酵母来源的商用PAL酶;此外,两种酶均能催化L-Phe和酪氨酸(L-tyrosine,L-Tyr)反应,且对L-Phe的催化效率较高,约为L-Tyr的5倍,脱除酸解酪蛋白中L-Phe的转化率分别为88%和93%。【结论】RmPAL和RdPAL具有较强稳定性和L-Phe水解偏好性,可从食源蛋白中有效去除L-Phe。

沧州市市售水产品污染状况研究

目的:了解沧州市售4类水产品中5种致病性弧菌和5种重金属的污染状况,为食品安全风险评估提供数据支持。方法:2021~2022年在沧州各县区随机采集水产品207份,以《国家食品污染和有害因素风险监测工作手册》为依据进行检测,并从多个维度对阳性检出率进行比较分析。结果:致病性弧菌在不同采样地点、不同采样季度、不同类别的水产品中阳性检出率比较差异具有统计学意义(χ^(2)=14.92,P=0.002;χ^(2)=39.733,P<0.001;χ^(2)=18.07,P=0.001);水产品中致病性弧菌检出率最高的采样地点、采样季度、水产品类别分别是农贸市场(52.4%)、第三季度(65.3%)、软体类(62.5%);重金属在水产品中均有检出,且镉超标率为1.44%。

基于ResNet50模糊称重装置双目识别系统的设计

针对肉类食品行业生产效率低,以及采用人工称重分拣的问题,设计了一种基于ResNet50的模糊称重装置双目识别系统,旨在实现称重设备的文字实时识别,提高后期分拣率。首先,设计一款模糊称重装置,用于对食品进行有效的定量称重;其次,选用双目相机作为称重装置的识别硬件,并进行标定;再次,设定称重食盒采集实验,并对食盒图像进行预处理;然后,以ResNet50前5层的残差网络为核心,利用CTPN算法对食盒图像进行模型训练,用LSTM神经网络、NMS算法对待测试图像数据特征序列进行预测;最后,利用LabVIEW软件设计文字实时监测界面,进行系统监测。经测试,系统网络的Precision、Recall、F-measure值分别达到98.64%、97.60%、98.12%,系统文字识别率得到有效提高,且能够进行实时监测。

不同转食策略对花斑副沙鳅仔鱼和稚鱼生长及存活率的影响

为研究不同转食策略对花斑副沙鳅(Parabotia fasciata)仔鱼和稚鱼生长及存活率的影响,探寻其最佳转食策略,设置5个转食起始点,分别为孵化出膜后第7天(W7组)、第9天(W9组)、第11天(W11组)、第13天(W13组)和第15天(W15)组,设计5个转食过渡时间,分别为2 d(W9-1组)、4 d(W9-2组)、6 d(W9-3组)、8 d(W9-4组)和10 d(W9-5组)。结果表明,孵化出膜23 d时,W13组试验鱼存活率最高,为83.33%,明显高于其余各组;孵化出膜11~15 d、15~19 d时,各组试验鱼特定生长率无显著差异(P>0.05),孵化出膜19~23 d时,W13组试验鱼特定生长率显著小于其余各组(P<0.05);W15组试验鱼体长和体重明显高于其余各组。W9-5组试验鱼存活率明显高于其余各组,孵化出膜25 d时,W9-5组试验鱼存活率为89.30%;孵化出膜21~25 d时,W9-1、W9-2组试验鱼特定生长率明显高于其余各组(P<0.05);W9-5组试验鱼体长和体重最大,其次是W9-4组,其余各组试验鱼体长和体重都随转食过度时间的缩短而降低。综合分析,推荐花斑副沙鳅仔鱼和稚鱼在孵化出膜13 d时开始转食,且以8 d作为转食的最佳过渡时间。

2023年海南省网络外卖餐饮食品微生物污染状况分析

目的:分析105批网络外卖餐饮食品微生物污染状况,为行政监管部门制定监管措施及相关标准制修订提供参考。方法:通过网络外卖App平台随机采样,按照《食品安全国家标准食品微生物学检验菌落总数测定》(GB 4789.2—2022)要求开展微生物和中心温度检测,并对检测结果不合格率进行统计学分析。结果:不同种类不合格率(χ^(2)=2.624,p> 0.05)、不同季度不合格率(χ^(2)=0.682,p> 0.05)、不同中心温度不合格率(χ^(2)=2.31,p> 0.05)均无统计学意义;菌落总数与其他微生物项目指标不合格率比较,均有极显著性差异(χ^(2)=48.451,p <0.01)。结论:本研究初步掌握了海南省网络外卖餐饮食品微生物污染的情况,为监管部门加强监管提供实验依据。