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Family planning technical services in China

Shang-Chun WU

《医学前沿（英文）》 2010年第4卷第3期页码 285-289 doi: 10.1007/s11684-010-0097-3

摘要： Family planning is a basic state policy in China. Its aim is to control population growth and to enhance population quality. Technical services are the key measures for implementing the family planning policy. In order to ensure that people use safe, effective, and appropriate contraceptive methods based on the government’s commitment, China has established countrywide family planning service networks down to the township level. The people can access various and convenient contraceptive services. In urban areas, all contraceptive services are free. The contraceptive prevalence rate in 2007 was 84.6%, the percentage of intrauterine device (IUD) was 52.3%, that of female sterilization was 32.3%, and that of vasectomy was 6.1%. This means that more than 90% of married childbearing couples were using long-term contraceptives. At the same time, the government gives priority to supporting research on contraceptive technology. Studies’ results have provided scientific evidence for development, introduction, and expansion of contraceptive methods, and also for establishment and revision of the technical guidelines. Great efforts have been made in promoting “human-oriented and client-centered” services during the recent ten years. Remarkable success has been achieved in improving the quality of technical services.

关键词： family planning contraceptive method service delivery

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流产后避孕咨询与教育对人工流产后妇女避孕行为的影响初探

袁钦钦,许良智,宿宓,聂颖

《中国工程科学》 2014年第16卷第5期页码 34-38

摘要：

探讨对人工流产术后女性加强流产后避孕咨询与教育对其避孕行为的影响。选择2011年8月1 日—2011 年9 月30 日在四川大学华西第二医院妇产科门诊自愿行人工流产术的女性200 人，进行术后常规处理（常规处理组）。选择2011 年10 月25 日—2012 年4 月10 日在四川大学华西第二医院妇产科门诊自愿行人工流产术的女性200 人，流产后常规处理并加强避孕咨询与教育（加强干预组），两组均于术后1 个月、3 个月、6 个月进行随访调查。常规处理组和加强干预组半年后随访率分别为46 %，71.5 %（P<0.01）。常规处理组和加强干预组流产后4 周内性生活的恢复率分别为10.8 %，3.5 %（P<0.05）；半年内加强干预组避孕行为的正确率高于常规处理组(P<0.01)，而且其避孕套、复方口服避孕药（COC）和节育环等现代避孕措施的使用率高于常规处理组(P<0.01)，安全期和体外排精等传统避孕方法使用率低于常规处理组（P<0.01）；常规处理组和加强干预组非意愿妊娠率分别为7.0 %，1.5 %（P>0.05）。研究表明，及时通过加强流产后避孕咨询与教育，能提高人工流产后女性的避孕意识，增加避孕知识，提高正确避孕措施的使用率，更好地促进了女性的生殖健康。

关键词：人工流产流产后咨询与教育避孕行为

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Meta-analysis of the risk factors of breast cancer concerning reproductive factors and oral contraceptive

Qiong DAI MD, Bei LIU MD, Yukai DU MM,

《医学前沿（英文）》 2009年第3卷第4期页码 452-458 doi: 10.1007/s11684-009-0080-z

摘要： The authors performed a meta-analysis of case-control studies that addressed whether reproductive factors and oral contraceptive use were associated with breast cancer by searching the MEDLINE, PubMed, Proquest, Embase, ScienceDirect, African Healthline, BMJ Health Intelligence and Chinese Periodical net databases for all English-language and Chinese-language papers published from January 1, 1997 to December 31, 2007. A total of 15 studies calculating pool ORs indicated that menopausal age >50yr [odds ratio (OR), 1.39; 95% confidence interval (CI), 1.22―1.57] and oral contraceptive use (OR, 2.12*, “*”: summary OR was adjusted; 95% CI, 1.24―3.62) were correlated with the increase in breast cancer risk while the summary OR based on number of full-term pregnancies ≥1 (OR, 0.63*; 95% CI, 0.60―0.68) and breast-feeding (OR, 0.76; 95% CI, 0.64―0.90) indicated no association with breast cancer risk. The correlation was statistically significant. Menopausal age >50yr and oral contraceptive use are positively correlated with an increase in breast cancer risk while breast-feeding and number of full-term pregnancies ≥1 are protective factors.

关键词： meta-analysis breast cancer risk factors reproductive factors oral contraceptive use

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不同民族流动育龄妇女的避孕状况分析

张君娴,杨婷,徐晓帆,龙春燕,刘建苏,李莉

《中国工程科学》 2015年第17卷第6期页码 57-60

摘要：

了解乌鲁木齐市流动育龄妇女的避孕状况，为今后开展避孕方法知情选择优质服务提供参考。采用分层-整群-随机抽样的方法，对18~50岁符合条件的对象进行问卷调查，主要包括人口学特征、避孕措施的使用情况等。采用卡方检验和多因素Logistic回归方法进行统计分析。本次调查的106 568例流动育龄妇女中，避孕方法使用比例为92.78 %，避孕方法的选择依次为宫内节育器（65.74 %）、药物（23.17 %，包括口服避孕药、皮下埋植剂、避孕针等含药避孕方法）、避孕套（9.06 %）、绝育术（2.03 %）。多因素Logistic回归分析显示民族、学历、职业、婚姻状况和性生活频率对避孕方法的使用有影响。应根据不同民族的情况和流动育龄妇女的人口学特征，提供有针对性和个性化的避孕方法知情选择指导和服务。

关键词：流动育龄妇女避孕状况分析

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北京市剖宫产育龄妇女产后避孕意愿分析

沈洁,高丽丽,潘迎

《中国工程科学》 2014年第16卷第5期页码 16-19

摘要：

为了了解北京市剖宫产术后妇女的避孕意愿及其影响因素，在北京市城、近、郊区采用分层整群抽样方法随机抽取2011 年7 月—2011 年12 月期间接受剖宫产手术的产妇364 名，进行问卷调查。采用卡方检验和多因素Logistic 回归方法对问卷调查结果进行分析。结果显示，被调查妇女平均年龄为（31±4.53）岁，剖宫产术后计划恢复性生活时间中位数为7 周。96.43 %的妇女对于产后可以采用的避孕方法并不清楚。仅有27.74 %的妇女表示产后会尽早或立即采取避孕措施，避孕套是妇女首选的产后避孕方法，占75.27 %。72.25 %的妇女没有避孕计划或要等到产后3 个月才开始避孕。62.64 %的妇女在剖宫产术后接受了避孕指导，医生推荐的产后避孕方法中避孕套占首位。医生强调剖宫产术后避孕的重要性、妇女具备正确产后避孕知识是妇女剖宫产术后尽早开始避孕的保护因素。剖宫产妇女对产后避孕服务有较高需求，希望在产前保健或产后访视时能得到专业人员的产后避孕咨询指导。剖宫产术后再次妊娠存在健康风险，剖宫产妇女产后尽早落实避孕措施应引起高度关注。建议尽快针对剖宫产妇女开展产后避孕服务，摸索适合北京的服务模式，以满足需求，减少产后非意愿妊娠的发生，降低剖宫产术后人工流产的风险。

关键词：育龄妇女剖宫产术后产后服务避孕

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天津滨海新区产后妇女对避孕相关问题的认知现状分析

秦丽艳

《中国工程科学》 2015年第17卷第6期页码 53-56

摘要：

通过对天津滨海新区产后妇女对避孕相关问题的认知现状的调查分析，以期认识到提高产后妇女的整体避孕意识的必要性。采用自行设计问卷，由固定医师进行询问并填写问卷。产后妇女中81.9 %的人知道产后应该避孕，但只有46.9 %知道产后高危人工流产的危害，48.8 %的产后妇女没有避孕计划或打算3个月后再采取避孕措施，47.2 %的产后妇女计划或已于首次性生活采取避孕措施，其中学历高、职业为干部组、剖宫产的产后妇女避孕意识较好，258人（80.6 %）通过住院分娩或产后访视得知产后应避孕，207人（64.7 %）在产后避孕方法上首选避孕套。产后妇女选择长效可靠避孕措施的少，医护工作者应提高对产后妇女有关产后避孕的指导和宣传，提高产后妇女对避孕效果可靠措施的使用率，提高产后妇女的生活质量。

关键词：产后妇女；避孕；人工流产

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新型立体式网状宫内节育器初步临床观察

邱毅,王磊光,于玲

《中国工程科学》 2014年第16卷第5期页码 39-46

摘要：

为了观察新型立体式网状宫内节育器（3-DR-IUD）的避孕效果及副反应，将152 例志愿受试者随机分为两组，即接受3-DR-IUD组和放置元宫药铜宫内节育器(2-D-IUD)组，每组各76 例，常规放置3-DR-IUD和2-D-IUD。分别于术后1 个月、3 个月、6 个月和12 个月进行随访，了解放置宫内节育器（IUD）后副反应（如腹痛、腰痛、阴道出血持续时间及出血量、白带等）的发生率、带器妊娠率、IUD脱落率、因症取出率、续用率及避孕效果，并利用B超、X光腹部平片检查3-DR-IUD位置等。两组各76 例均成功放置了IUD，术中均无明显疼痛。3-DR-IUD组术后出现白带增多、月经期延长、不规则出血、月经量增多及腰腹部疼痛等副反应6例(7.9%)，而2-D-IUD组出现31例（40.8%），两组比较差异有统计学意义(P<0.000 1)。3-DR-IUD 组无脱落，无带器妊娠者，3 个月时因对硅橡胶过敏取出1 例，12 个月时终止率为1.3 %，续用率为98.7 %（75/76）；2-DIUD组终止率为13.2 %，续用率为86.8 %（66/76），两组比较差异有统计学意义(P=0.009)。实验结果表明，3-DR-IUD具有很好的避孕效果，术后副反应轻微，可为育龄妇女提供新的、安全、高效的IUD。

关键词： 3-DR-IUD 临床实验副反应避孕效果

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囊型宫内节育器避孕材料的细胞毒性研究

钟兴明,韦相才,朱国平,李艳秋,伍园园,李志才,郭建华,曾幸荣

《中国工程科学》 2015年第17卷第6期页码 8-12

摘要：

目的：对囊型宫内节育器避孕材料的细胞毒性的潜在性作出评价。方法：采用研制的硅橡胶材料与高密度聚乙烯材料作为对照，根据GBT 16886.5―2003医疗器械生物学评价第5部分标准，设立空白对照组、阴性对照（高密度聚乙烯）浸提液组、阳性对照液（含6.3 %苯酚的RPMI1640完全培养液）组、100 %、50 %和25 %材料（硅橡胶）浸提液组共6个组；用RPMI 1640完全培养液培养L-929细胞，每组加入100 μL的空白对照液、阴性对照浸提液和25 %、50 % 、100 %的材料浸提液及阳性对照液，观察细胞形态和增值率。结果：空白对照组、阴性对照浸提液组、阳性对照组、100 %、50 %和25 %浓度材料浸提液组的细胞毒性级别分别为：0级、1级、4级、2级、2级、1级。100 %、50 %和 25 %材料浸提液组培养72 h后细胞增值率分别是（66.2 ± 4.3） %、（72.4 ± 6.1） %、（81.1 ± 4.2 ） %；阴性对照浸提液组、100 %、50 %、25 %材料浸提液组和阳性对照浸提液组OD（optical density）值与空白对照组比较差异有统计学意义（P <0.05）；空白对照组、100 %、50 %材料浸提液和阳性对照液组OD值与阴性对照浸提液组差异有统计学意义（P <0.05）；25 %材料浸提液OD值和与阴性对照浸提液组差异无统计学意义（P >0.05）。结论：根据GBT 16886.5―2003医疗器械生物学评价第11部分标准，所测硅橡胶材料细胞毒性评价符合要求。

关键词：宫内节育器；硅橡胶材料；细胞毒性；动物实验；鼠

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Comparison of shallow tunneling method with pile and rib method for construction of subway station in

Sina AMIRI; Ali Naghi DEHGHAN

《结构与土木工程前沿（英文）》 2022年第16卷第6期页码 704-717 doi: 10.1007/s11709-021-0746-4

摘要： In the present study, a comparison between the new shallow tunneling method (STM) and the traditional pile and rib method (PRM) was conducted to excavate and construct subway stations in the geological conditions of Tehran. First, by selecting Station Z6 located in the Tehran Subway Line 6 as a case study, the construction process was analyzed by PRM. The maximum ground settlement of 29.84 mm obtained from this method was related to the station axis, and it was within the allowable settlement limit of 30 mm. The acceptable agreement between the results of numerical modeling and instrumentation data indicated the confirmation and accuracy of the excavation and construction process of Station Z6 by PRM. In the next stage, based on the numerical model validated by instrumentation data, the value of the ground surface settlement was investigated during the station excavation and construction by STM. The results obtained from STM showed a significant reduction in the ground surface settlement compared to PRM. The maximum settlement obtained from STM was 6.09 mm as related to the front of the excavation face. Also, the sensitivity analysis results denoted that in addition to controlling the surface settlement by STM, it is possible to optimize some critical geometric parameters of the support system during the station excavation and construction.

关键词： shallow tunneling method pile and rib method ground surface settlement subway station construction numerical modeling

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Development of a new method for RMR and Q classification method to optimize support system in tunneling

Asghar RAHMATI,Lohrasb FARAMARZI,Manouchehr SANEI

《结构与土木工程前沿（英文）》 2014年第8卷第4期页码 448-455 doi: 10.1007/s11709-014-0262-x

摘要： Rock mass classification system is very suitable for various engineering design and stability analysis. classification method is confirmed by Japan Highway Public Corporation that this method can figure out either strength or deformability of rock mass, further appropriating the amount of rock bolts, thickness of shotcrete, and size of pitch of steel ribs just after the blasting procedure. Based on these advantages of method, in this study, according to data of five deep and long tunnels in Iran, two equations for estimating the value of method from and classification systems were developed. These equations as a new method were able to optimize the support system for and classification systems. From classification and its application in these case studies, it is pointed out that the method for the design of support systems in underground working is more reliable than the and classification systems.

关键词： JH classification Q and RMR classification new method

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Independent cover meshless particle method for complex geotechnical engineering

Jianqiu WU, Yongchang CAI

《结构与土木工程前沿（英文）》 2018年第12卷第4期页码 515-526 doi: 10.1007/s11709-017-0428-4

摘要： A new Independent Cover Meshless Particle (ICMP) method is proposed for the analysis of complex geotechnical engineering. In the ICMP method, the independent rectangular cover regardless of the shape of the analysis model is employed as the influence domain of each discrete node, the general polynomial is employed as the meshless interpolation function of the independent nodal cover, and the Cartesian Transformation Method (CTM) is used for the numerical integration of the nodal covers cut by material interfaces, joints, cracks and faults. The present method has a simple formulation and a low computational cost, and is easy for the numerical analysis and modeling of complex geotechnical engineering. Several typical numerical examples are presented to demonstrate the accuracy and robustness of the proposed method.

关键词： meshless method particle method independent cover CTM geotechnical engineering

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3D mode discrete element method with the elastoplastic model

Wei HU, Feng JIN, Chong ZHANG, Jinting WANG

《结构与土木工程前沿（英文）》 2012年第6卷第1期页码 57-68 doi: 10.1007/s11709-012-0139-9

摘要： The three-dimensional mode-deformable discrete element method (3MDEM) is an extended distinct element approach under the assumptions of small strain, finite displacement, and finite rotation of blocks. The deformation of blocks is expressed by the combination of the deformation modes in 3MDEM. In this paper, the elastoplastic constitutive relationship of blocks is implemented on the 3MDEM platform to simulate the integrated process from elasticity to plasticity and finally to fracture. To overcome the shortcomings of the conventional criterion for contact fracturing, a new criterion based on plastic strain is introduced. This approach is verified by two numerical examples. Finally, a cantilever beam is simulated as a comprehensive case study, which went through elastic, elastoplastic, and discontinuous fracture stages.

关键词： mode discrete element method elastoplastic numerical method discontinuum contact

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The smoothed finite element method (S-FEM): A framework for the design of numerical models for desired

Gui-Rong Liu

《结构与土木工程前沿（英文）》 2019年第13卷第2期页码 456-477 doi: 10.1007/s11709-019-0519-5

摘要：

The smoothed finite element method (S-FEM) was originated by G R Liu by combining some meshfree techniques with the well-established standard finite element method (FEM). It has a family of models carefully designed with innovative types of smoothing domains. These models are found having a number of important and theoretically profound properties. This article first provides a concise and easy-to-follow presentation of key formulations used in the S-FEM. A number of important properties and unique features of S-FEM models are discussed in detail, including 1) theoretically proven softening effects; 2) upper-bound solutions; 3) accurate solutions and higher convergence rates; 4) insensitivity to mesh distortion; 5) Jacobian-free; 6) volumetric-locking-free; and most importantly 7) working well with triangular and tetrahedral meshes that can be automatically generated. The S-FEM is thus ideal for automation in computations and adaptive analyses, and hence has profound impact on AI-assisted modeling and simulation. Most importantly, one can now purposely design an S-FEM model to obtain solutions with special properties as wish, meaning that S-FEM offers a framework for design numerical models with desired properties. This novel concept of numerical model on-demand may drastically change the landscape of modeling and simulation. Future directions of research are also provided.

关键词： computational method finite element method smoothed finite element method strain smoothing technique smoothing domain weakened weak form solid mechanics softening effect upper bound solution

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Explicit optimization method for cutting-screw-thread on the basis of dual-RSM

Zhengbao LEI, Shubin WEI, Qingyun DU

《机械工程前沿（英文）》 2010年第5卷第4期页码 423-430 doi: 10.1007/s11465-010-0109-7

摘要： To obtain the explicit function for optimizing the cutting-screw-thread (CST) in crash, the simulations of frontal crash at the speed of 56 km/h have been carried out in VPG. The peak acceleration in crash has been taken as the evaluation index of energy absorption characteristics. First, the single factor experiment was taken based on six parameters affecting on the absorption characteristics of CST. Second, the peak acceleration function of each parameter by using response surface method (RSM) is obtained. Third, the explicit resultant peak acceleration function of six parameters by using RSM again is obtained. A dual RSM-based explicit method is proposed. According to this function, the best size dimensions of CST in different crash conditions could be easily obtained. Finally, an example shows that the values of the calculation errors for simulation value and target value (40 g) are 3.6% and 1.3%, respectively. This method can satisfy the demand for engineering accuracy.

关键词： vehicle engineering crash safety explicit method response surface method

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Application of random set method in a deep excavation: based on a case study in Tehran cemented alluvium

Arash SEKHAVATIAN, Asskar Janalizadeh CHOOBBASTI

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 66-80 doi: 10.1007/s11709-018-0461-y

摘要： The design of high-rise buildings often necessitates ground excavation, where buildings are in close proximity to the construction, thus there is a potential for damage to these structures. This paper studies an efficient user-friendly framework for dealing with uncertainties in a deep excavation in layers of cemented coarse grained soil located in Tehran, Iran by non-deterministic Random Set (RS) method. In order to enhance the acceptability of the method among engineers, a pertinent code was written in FISH language of FLAC2D software which enables the designers to run all simulations simultaneously, without cumbersome procedure of changing input variables in every individual analysis. This could drastically decrease the computational effort and cost imposed to the project, which is of great importance especially to the owners. The results are presented in terms of probability of occurrence and most likely values of the horizontal displacement at top of the wall at every stage of construction. Moreover, a methodology for assessing the credibility of the uncertainty model is presented using a quality indicator. It was concluded that performing RS analysis before the beginning of every stage could cause great economical savings, while improving the safety of the project.

关键词： uncertainty reliability analysis deep excavations random set method finite difference method