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Fiber orientation is a big challenge in short fiber reinforced composites. Powder injection molding (PIM) process has some intrinsic fiber alignment associated with it. During PIM process fibers in skin region of moldings are aligned as these regions experience higher shear flow caused by the mold walls. Fibers in the core region remain randomly aligned as these regions are far from mold walls and experience lesser shear flow. In this study short carbon fiber (CF) reinforced copper matrix composite was developed by PIM process. Two copper composite feedstock formulations were prepared having 5 vol% and 10 vol% CFs and a wax based binder system. Fiber orientation was controlled during injection molding by using a modified mold that has a diverging sprue. The sprue creates converging flow when feedstock enters into the mold cavity. Fiber orientation was analysed after molding using FESEM. The orientation of fibers can be controlled by controlling flow of feedstock into the mold.

Spectrum above 90 GHz is a promising investigation domain to offer future wireless networks with performance beyond IMT 2020 such as $100+$ Gbit/s data rate or sub-ms latency. In particular, the huge available bandwidth can serve the backhaul transport network in the perspective of future ultra-dense deployments, and massive front-haul data streams. This paper investigates the feasibility and characteristics of the in-street sub-THz mesh backhauling. The study relies on the highly realistic simulation of the physical layer performance, based on detailed geographical representation, ray-based propagation modelling, RF phase noise impairment, and a new modulation scheme robust to phase noise. The achievable throughput is studied, and it is shown that each link of a dense mesh backhaul network can reliably deliver several Gbit/s per 1-GHz carrier bandwidth. The multi-path diversity is assessed, as well as the impact of rainfall and phase noise level.

As part of the search for alternatives to transurethral resection of the prostate (TURP) attention has (re)turned to laser methods. We describe our experience with the currently available endoscopic beam deflection devices, particularly the Prolase II. 25 patients, generally with medical reasons to avoid TURP, and with proven bladder outlet obstruction (BOO) due to benign prostatic enlargement (BPH) underwent prostatic laser coagulation. Average age was 72 years (range 57-84), mean prostatic size by transrectal ultrasound (TRUS) was 48 g (15-100), average pretreatment peak flow rate (FR) was 7.6 ml/s (4.56-12.4). All patients were markedly symptomatic. Patients underwent clinical examination, Prostate specific antigen assay (PSA = 3.75, range 0.1-10.2), and TRUS preoperatively to exclude prostate cancer. After cystoscopic assessment the prostate was lasered according to the device manufacturers recommendations and clinical experience. A suprapubic catheter (SPC) and urethral catheters were inserted, the urethral for 24 hours. If voiding was satisfactory the SPC was removed after 24-48 hrs. Alternatively the patient was discharged and assessed at weekly intervals for SPC removal. Mean duration of SPC drainage was 11 days. Total mean impatient stay was 4.5 days (2-13) during a mean of 2 admissions. Blood loss was minimal and there were no other significant complications. At a minimum follow up of 3 months mean peak FR was 15.3 ml/s (9-31). Symptom scores (IPSS) fell from a mean of 21 to 10 by 3 months after treatment. There was an initial period of irritability for up to 12 weeks but symptomatic improvement was noted in all.