Billings生育调节法应用于哺乳期妇女的临床实验研究

近年来，我国响应世界卫生组织和联合国儿童基金会的号召，为实现产后４～６个月内完全母乳喂养率达８０％的总目标而努力。文献报道完全母乳喂养并处于闭经阶段４～６个月内，采用生育调控法，其避孕效果可达９８％［１］。我院在１９９５年建立了爱婴医院，为了保护婴儿...

稽留流产、葡萄胎妇女使用Billings法避孕效果观察

目的:观察稽留流产和葡萄胎妇女刮宫术后采用Billings法避孕的效果。方法:观察组46例,为我院住院治疗的稽留流产和葡萄胎行刮宫术后采用Billings法避孕者,同时随机抽取我院Billings门诊避孕的妇女92例为对照组,观察两组对象24个月内的停用率、续用率和意外妊娠率。结果:138例妇女共观察1501个妇女月,24个月内观察组除6例计划妊娠外,无停用和意外妊娠者,净累积续用率86.95%。对照组24个月内停用17例(18.47%),意外妊娠1例(1.08%),净累积续用率81.52%。结论:稽留流产、葡萄胎妇女采用Billings法避孕,效果良好,值得推荐应用。

Billings排卵法在避孕与受孕的应用研究

为了探讨Ｂｉｌｌｉｎｇｓ排卵法的可应用性，对１７５例妇女应用Ｂｉｌｌｉｎｇｓ排卵法调节生育进行了观察。其中避孕（Ａ组）１５５例，受孕（Ｂ组）２０例，共观察１１３３个月经周期。结果表明：Ａ组与方法有关的妊娠率为０．１％，避孕有效率为９８，８％妇女年；Ｂ组受孕成功率为９０．Ｏ％。本方法不受文化、职业限制。３个月经周期内学会使用者为８６．３％，认为使用方便者９４．９％，坚持应用者９３，７％。认为Ｂｉｌｌｉｎｇｓ排卵法是一种方便、易学、安全、可靠的人类生殖调节技术。

上海市688对育龄夫妇连续使用Billings自然避孕法的临床效果观察及实验研究

本研究在1988,6～1990,5的两年间,对688对育龄夫妇进行了连续使用Billings 法的避孕效果与续用情况的观察,共10,275个妇女月;其中,550对夫妇连续使用12个月以上。用生命表统计分析,18个月和12个月时净累积停用率分别为34.58%和19.85%,续用率分别为65.42%和80.15%(因方法学意外妊娠分别为1.18%和1.02%,因方法学停用分别为2.84%和1.61%)。在观察临床效果的同时,对67例使用该法的志愿者进行阴道脱落细胞学检查,10例血、尿LH 和35例尿雌、孕激素测定。本文还对两年来临床观察和实验研究的多个方面进行了讨论,并认为该法值得进一步研究,可有组织、有计划地逐步扩大应用。

Billings自然避孕法作为计划生育措施的临床初试

113名育龄妇女根据不同要求用Billings自然避孕法作为计划生育措施,共428个周期;其中要求避孕及延缓受孕76名,避孕成功率为92.59%(妇女年)。本法安全、有效、简便、经济,对自愿暂缓生育的新婚夫妇及不适应现有避孕方法的夫妇更为适用,也能为不同文化程度的人所接受,是一种值得进一步研究、逐步推广应用的计划生育措施。

Blockchain and MEC-Assisted Reliable Billing Data Transmission over Electric Vehicular Network:An Actor–Critic RL Approach

Recently,electric vehicles(EVs)have been widely used under the call of green travel and environmental protection,and diverse requirements for charging are also increasing gradually.In order to ensure the authenticity and privacy of charging information interaction,blockchain technology is proposed and applied in charging station billing systems.However,there are some issues in blockchain itself,including lower computing efficiency of the nodes and higher energy consumption in the consensus process.To handle the above issues,in this paper,combining blockchain and mobile edge computing(MEC),we develop a reliable billing data transmission scheme to improve the computing capacity of nodes and reduce the energy consumption of the consensus process.By jointly optimizing the primary and replica nodes offloading decisions,block size and block interval,the transaction throughput of the blockchain system is maximized,as well as the latency and energy consumption of the system are minimized.Moreover,we formulate the joint optimization problem as a Markov decision process(MDP).To tackle the dynamic and continuity of the system state,the reinforcement learning(RL)is introduced to solve the MDP problem.Finally,simulation results demonstrate that the performance improvement of the proposed scheme through comparison with other existing schemes.

Kernel Generalization of Multi-Rate Probabilistic Principal Component Analysis for Fault Detection in Nonlinear Process

In practical process industries,a variety of online and offline sensors and measuring instruments have been used for process control and monitoring purposes,which indicates that the measurements coming from different sources are collected at different sampling rates.To build a complete process monitoring strategy,all these multi-rate measurements should be considered for data-based modeling and monitoring.In this paper,a novel kernel multi-rate probabilistic principal component analysis(K-MPPCA)model is proposed to extract the nonlinear correlations among different sampling rates.In the proposed model,the model parameters are calibrated using the kernel trick and the expectation-maximum(EM)algorithm.Also,the corresponding fault detection methods based on the nonlinear features are developed.Finally,a simulated nonlinear case and an actual pre-decarburization unit in the ammonia synthesis process are tested to demonstrate the efficiency of the proposed method.

Performance Improvement of DCF Supporting Multi-Rate in IEEE 802.11b Wireless LAN

This paper proposes a new channel access algorithm based on channel occupancy time （COT） fairness to guarantee fairness and improve the aggregate throughput of 802.11b multi-rate WLANs. In the algorithm, the COT is used as fairness index to analyze the fairness of WLANs instead of the channel access probability （CAP） used in the distributed coordination function （DCF）. The standard COT is given by access point （AP） and broadcasted to all wireless stations. The AP and wireless stations in the WLAN can achieve COT-based fairness by adjusting their packet length, sending the multiple back-to-back packets at one time, or giving up an opportunity to access the channel. Analysis and simulations show that our algorithm can provide COT-fairness. Compared with the CAP-based algorithm, the proposed algorithm leads to improvements in aggregate throughput of IEEE 802. lib multi-rate WLANs.

Billings自然避孕法应用中阴道细胞形态及LH水平观察

本文报道应用Billings自然避孕法时观察宫颈粘液和阴道细胞学的关系。67名妇女70周期提供了1587张阴道涂片,每例阴道涂片均显示乳酸杆菌及排卵型图象。KP1峰日在粘液峰日前后两天范围内的共有62周期,占88.6%,KP1峰日在粘液峰日后为0.01天。KP1峰日前共有粘液日为4.69天。10名妇女提供血和尿标本作血清LH 放射免疫及尿LH酶标测定。KPⅠ峰日在LH 峰日后为0.5天,粘液峰日在LH 峰日后为0.4天。

The Application of Billings for Fertility RegulationMethod during the Period of Breastfeeding

In order to adopt Billings Method for fertility regulation during the period of breast feeding, cervical mucus was observed and monitored in 61 breast feeding mothers.Urine estrogen and /or pregnanediol were/was measured in 15 breast feeding mothers. Observations on cervical mucus during 244 months were collected. The type of dry or no mucus was observed in 75.27% fully breast feeding mothers. Constant unchanging mucus was observed in 69.39% partially breast feeding mothers. Developmental changing mucus was observed in 79.25% of mothers bottle feeding their infants. According to the record on cervical mucus within 6 months postpartum, 97.14% of the cervical mucus was consistent with normal menstrual cycles. Urine estrogen and /or pregnanediol were/was measured in 15 breast feeding mothers. The level of estrogen in urine averaged 0.08 μmol/24 h in fully breast feeding mothers and 0.14 μmol/24 h in partially breast feeding mothers.The peak level averaged 0.21 μmol/24 h in bottle feeding mothers.The pregnanediol level was determined to confirm ovulation in bottle feeding mothers. The average levels of cut off and the period of ovulation in 6 bottle feeding mother were 7 μmol/24 h and 9 μmol/24 h respectively.Measurement of urine estrogen and pregnanediol level all matched with cervical mucus appearances. Conclusion: Billings Method is a simple, scientific method for contraception without side effects during breast feeding period.

The Clinical and Experimental Research on Billings Ovulation Method During Breastfeeding

Objective The effectiveness and acceptability of Billings Ovulation Method (BOM) during breastfeeding were studied. At the same time, the monitoring indexes of fertility return were studied.Methods It was a clinical comparative study of BOM and IUD containing copper (200mm 2). The annual rate of pregnancy, discontinuation rate and continuation rate in the two groups was determined. The serum prolactin and estradiol in 90 breastfeeding mothers and urine estrogen and pregnanediol in different feeding mothers were measured.Results There were 219 subjects in the BOM group and 200 in the IUD group. The pregnancy rate in this two groups was 1. 43% and 1. 54% respectively. The rates of discontinuation and continuation in the IUD group were:8. 87% and 91. 35% as well as in the BOM group were 8. 53% and 90. 17% respectively. Neither result was statistically significant (P>0. 05). The experimtal research showed that menses return was well estimated by 0. 35 ratio of serum prolactin vs. estrodiol. Sensitivity and specificity was 94. 61% and 84. 61% respectively. It also indicated that (1) the levels of urine hormone were closely related to the patterns of cervical mucus and (2) the incidence of ovulating before the second return of menses in partially breastfeeding mothers was much lower than that of bottle-feeding mothers (47. 05% vs. 94. 20%). Conclusion BOM is a simple, reliable and well accepted contraceptive method of during breastfeeding. If it can be combined with the measurement of serum prolactin/ estradiol, the date of menses return will be determined more easily. Encouraging mothers to breast-feed will be beneficial to the health of both babies and mothers and delay the fertility return of mothers.

Study of multi-rate multi-user detection based on supervision decision

Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework with parallel interference cancellation, a supervision decision algorithm based on pre-decision of probabilistic data association (PDA) and hard decision is proposed. The detection performance is analyzed and simulation is implemented to show that the supervision decision algorithm improves the detection performance effectively.

A SINGLE PROCESSOR MULTI-RATE VOCODER

This paper presents the design of a full-duplex multi-rate vocoder which implements an LPC-10, CELPC and VSELPC algorithms in real time. A single commercially available digital signal processor IC, the TMS320C25, is used to perform the digital processing. The channel interfaces are configured with the design of ASIC, and including timing and control logic circuits.

Multi-rate tracking controller analysis and design for target tracking systems

As the sampling rates of the inner loop and the outer loop of the target tracking control system are different,a typical digital multi-rate control system was formed.If the traditional single-rate design method was applied,the low sampling rate loop will seriously impact the dynamical characteristic of the system.After analyzing and calculating the impact law of the low sampling rate loop to the bandwidth and the stability of the tracking system,a kind of multi-rate control system design method was introduced.Corresponding to the different sampling rates of the inner loop and the outer loop,the multi-rate control strategy was constituted by a high sampling rate sub-controller and a low sampling rate sub-controller.The two sub-controllers were designed separately and connected by means of the sampling rate converter.The low sampling rate controller determined the response rapidity of the system,while the high sampling rate controller applied additionally effective control outputs to the system during a sampling interval of the low sampling rate controller.With the introduced high and low sampling rates sub-controllers,the tracking control system can achieve the same performance as a single-rate controller with high sampling rate,yet it works under a much lower sampling rate.The simulation and experimental results show the effectiveness of the introduced multi-rate control design method.It reduces the settling time by 5 times and the over shoot by 4 times compared with the PID control.

Multi-rate sensor fusion-based adaptive discrete finite-time synergetic control for flexible-joint mechanical systems

This paper proposes an adaptive discrete finite-time synergetic control （ADFTSC） scheme based on a multi-rate sensor fusion estimator for flexible-joint mechanical systems in the presence of unmeasured states and dynamic uncertainties. Multi-rate sensors are employed to observe the system states which cannot be directly obtained by encoders due to the existence of joint flexibilities. By using an extended Kalman filter （EKF）, the finite-time synergetic controller is designed based on a sensor fusion estimator which estimates states and parameters of the mechanical system with multi-rate measurements. The proposed controller can guarantee the finite-time convergence of tracking errors by the theoretical derivation. Simulation and experimental studies are included to validate the effectiveness of the proposed approach.

A NOVEL CROSS-LAYER STRATEGY OF VIDEO TRANSMISSION TO SOLVE PERFORMANCE ANOMALY IN MULTI-RATE IEEE 802.11 NETWORKS

When wireless hosts use different rates to transmit data in IEEE 802.11 networks, it will take on the state of performance anomaly which will severely decrease the throughputs of all the higher rate hosts. Hence, it is bad for video service transmission. Considering that video is very sensitive to packet delivery delay but can tolerate some packet losses, we propose a novel cross-layer scheme which takes these two characteristics into consideration. Firstly, the maximum number of retransmissions for a video Medium Access Control (MAC) frame is computed in MAC layer according to video frame rate requirement of application layer and current access delay of MAC layer. Secondly, within the margin of the tolerant Packet Loss Rate (PLR) of application layer, several video MAC frames are allowed to drop so that we can adaptively select the transmission rate as high as possible for the rest of video MAC frames in terms of current channel quality and the maximum number of retransmissions. Experiment results show that the proposed method can reduce the delay and jitter of video service and improve the throughputs of fast hosts. Therefore, it increases the quality of reconstructed video to a certain extent and relieves the performance anomaly of network effectively.

BLIND DETECTION FOR MULTI-RATE DS-CDMA SYSTEM WITH ANTENNA ARRAY AT THE BASE STATION

In this paper, we propose the blind space-time high rate multi-user detector for synchronous uplink multi-rate Direct Sequence Code Division Multiple Access （DS-CDMA） systems with antenna array at the base station. By employing antenna array at the base stations, the spatial dimension is used efficiently to suppress co-channel interference and increase the capacity for multi-rate CDMA system. After low rate physical users in the system are modeled as corresponding high rate virtual users, we construct the space-time signature vectors of virtual users. And subspace projection algorithm is employed to estimate space-time signature vectors blindly. Then a soft-decision high rate lnultiuser detector is proposed based on the estimated signature vectors, which avoids estimating the ambiguous complex factors which are necessary in traditional blind detector. Numerical simulation results evaluate the performance in terms of Bit Error Rate （BER） for the proposed scheme. Simultaneously, it demonstrates that the system capability increases two times when using twoelement antenna array.

A policy-based billing management architecture for the next generation IP-based network

IP billing is not only a basic functionality to operate IP sen＇ices, but also it is fundamental to offer customers with a stable and QoS-enabled network environment. As IP-based network has been widely agreed to be the core network of NGN, and existing IP billing system is too simple to fulfill the emerging requirements, the next generation IP billing has become an interesting topic in recent years. Policy-based management brings flexibility and scalability to systems by describing management logic and functions through policies, and thus reduces the complexity of the management of large-scale systems. Working on existing efforts, this paper proposed an improved IETF policy framework based upon which a policy-based billing management architecture for the next generation IP-based network was presented. Then a prototype with some basic functionalities was developed. The results of the experiment validated the expected improvements specified in this paper.

A NEW DESIGN METHOD OF CDMA SPREADING CODES BASED ON MULTI-RATE UNITARY FILTER BANK

It is well-known that the multi-valued CDMA spreading codes can be designed by means of a pair of mirror multi-rate filter banks based on some optimizing criterion. This paper indicates that there exists a theoretical bound in the performance of its circulating correlation property, which is given by an explicit expression. Based on this analysis, a criterion of maximizing entropy is proposed to design such codes. Computer simulation result suggests that the resulted codes outperform the conventional binary balanced Gold codes for an asynchronous CDMA system.

CHANNEL ESTIMATION OF MULTI-RATE DS-CDMA SIGNALS IN SLOW FADING MULTIPATH CHANNELS

In Direct-Sequence Code Division Multiple Access(DS-CDMA) mobile communi-cation systems, it is very important to obtain accurate estimation of the channel parameters,especially that of the propagation delay. But the near-far problem may make the estimationcomplicated and can degrade the estimation performance significantly. In this paper, an efficientMaximum Likelihood (ML) method is presented for channel parameter estimation of multi-rateDS-CDMA systems in slow fading multipath channels in a near-far scenario. The algorithmextended the ML approach to multi-rate DS-CDMA systems, and proposes decomposing a multi-dimensional optimization problem into a series of one-dimensional optimization and has improvedcomputational efficiency. Theoretical analysis and numerical examples show that the estimatorproposed is effective and near-far resistant.