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There is a growing demand for point cloud data that can produce reliable single-tree measurements. The most common platforms for obtaining such data are unmanned aircraft systems with passive sensors (UAS), unmanned aircraft equipped with aerial lidar scanners (ALS), and mobile lidar scanners (MLS). Our objectives were to compare the capabilities of the UAS, ALS, and MLS to locate treetops and stems and to estimate tree lean. The platforms were used to produce overlapping point clouds of a mature Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand, from which 273 trees were manually identified. Control trees were used to test tree detection accuracy of four algorithms and the number of stems detectable using each platform. Tree lean was calculated in two ways: using the stem location near the canopy and using the treetop. The treetops were detected more accurately from ALS and UAS clouds than from MLS, but the MLS outperformed ALS and UAS in stem detection. The platform influenced treetop detection accuracy, whereas the algorithms did not. The height estimates from the ALS and MLS were correlated (R2 = 0.96), but the MLS height estimates were unreliable, especially as distance from the scanner increased. The lean estimates using the stem locations or treetop locations produced analogous distributions for all three platforms.

In forestry, common garden experiments traditionally require manual measurements and visual inspections. Unmanned aircraft systems (UAS) are a newer method of monitoring plants that is potentially more efficient than traditional techniques. This study had two objectives: to assess the size and mortality of Pinus strobiformis Engelm. seedlings using UAS and to predict the second-year seedling size using manual measurements from the first year and from UAS size estimates. Raised boxes containing 150 seedlings were surveyed twice, one year apart, using multispectral UAS. Seedling heights and diameters at root collar (DRC) were measured manually in both years. We found that size estimates made using a vegetation mask were suitable predictors for size, while spectral indices were not. Furthermore, we provided evidence that inclusion of UAS size estimates as predictors improves the fit of the models. Our study suggests that common variables used in forest monitoring are not necessarily best suited for seedlings. Therefore, we created a new variable, called the longitudinal area (height × DRC), which proved to be a significant predictor for both height and DRC. Finally, we demonstrate that seedling mortality can be effectively measured from remotely sensed data, which is useful for common garden and regeneration studies.

IntroductionRecent studies have shown an increasing number of overweight and obese members serving in many armies. Overweight and obesity can be estimated using either body mass index or waist circumference measures. The aim of this research was to estimate the proportion of the Australian Army considered to be overweight and obese by waist circumference using the proxy measure of issued combat uniform waist size.MethodThe Australian Army has been progressively replacing combat uniforms with a new uniform design and camouflage pattern since 2016. The total number of issued combat uniforms by size was obtained from the points of issue for the three Australian Army combat brigades from the first issue of the new uniform in January 2016 through to November 2019. The waist size of issued combat pants was collated from each of the three points of issue, adjusted for measured waist size accuracy and sex, and analysed to estimate the proportion of overweight and obese soldiers in the Australian Army.ResultsThere were a total of 155 735 combat pants issued across the three points of issue. The mean waist size based on combat uniform pant size was found to be 90.4 cm, with an SD of 7.5 cm. Based on these data, approximately 23.3% of the Australian Army population can be estimated to be overweight and an additional 4.5% to be obese.ConclusionsThe Australian Army, like many western armies, has a significant proportion of overweight personnel. This can negatively affect operational capability, health and future healthcare costs both within the military and to society after military service has concluded. This is the first study to use a uniform waist size as a proxy to estimate overweight and obesity. This technique has application for the military, emergency services or any other organisation in which uniforms are provided.

Effective forest fire fighting involves alerting firefighting teams immediately in the case of a fire so that teams can promptly arrive the fire scene. The most effective way for an early detection of forest fires is monitoring of forest lands from fire lookout towers. Especially in fire sensitive forest lands, towers should be systematically located in such a way that fire lookout personnel can monitor the largest amount of forest land as possible. In this study, the visibility capabilities of lookout towers located in Köyceğiz Forest Enterprise Directorate (FED)in the city of Muğla in Turkey were evaluated by using Geographical Information System (GIS) based visibility and suitability analysis. The results of visibility analysis indicated that 77.12% of forest land were visible from the current towers. To extend the proportion of visible forest lands, locations of additional lookout towers were evaluated using spatial visibility and suitability analysis in which the tower locations were examined by considering specific criteria (i.e. distance to roads, elevation, ground slope, topographic features). Suitability analysis results identified five new towers in addition to current towers in the study area. The results indicated that visible forest lands increased to 81.47% by locating new towers, and increase of almost 4.35%. In addition, over half of the forests became visible by at least two towers when including five towers suggested by suitability analysis. The GIS-based method developed in this study can assist fire managers to determine the optimal locations for fire lookout towers for effective fire management activities., Učinkovito suzbijanje šumskih požara uključuje trenutno uzbunjivanje protupožarnih timova u slučaju požara kako bi mogli na vrijeme stići na mjesto požara. Najučinkovitiji način ranog uočavanja šumskog požara je nadzor šumskih područja s tornjeva za nadzor požara. Tornjevi bi trebali biti sustavno smješteni na način da osoblje za nadzor može nadzirati najveću moguću površinu šume, osobito u ugroženijim šumskim predjelima. U ovom su istraživanju procijenjene mogućnosti promatranja tornjeva za nadzor smještenih u šumariji Köyceğiz, u gradu Muğla u Turskoj pomoću analize vidljivosti i prikladnosti potpomognutom Geografskim informacijskim sustavom (GIS). Rezultati analize vidljivosti pokazali su da je 77,12 % šumskog područja vidljivo sa sadašnjih tornjeva. Kako bi se povećao udio vidljivoga šumskog područja, lokacije dodatnih tornjeva za nadzor procijenjene su pomoću analize prostorne vidljivosti i prikladnosti u kojoj su lokacije tornjeva ispitane razmatrajući specifične kriterije (npr. udaljenost od cesta, visina, nagib terena, topografske karakteristike). Rezultati analize prikladnosti identificirali su pet novih tornjeva uz sadašnje tornjeve na promatranome području. Rezultati su pokazali da bi se dodavanjem novih tornjeva vidljiva šumska površina povećala na 81,47 %, što je povećanje od gotovo 4,35 %. Uz to, analiza prikladnosti pokazala je da bi preko polovice šume bilo vidljivo s najmanje dva tornja kada bi se dodalo ovih pet tornjeva. Metoda potpomognuta GIS-om razvijena u ovome istraživanju može pomoći upraviteljima za zaštitu od požara da odrede optimalne lokacije za tornjeve za nadzor požara u svrhu učinkovitih protupožarnih aktivnosti.

Correction to: Space Sci. Rev. (2020) 216: 103 Affiliation 2 in this article is the wrong affiliation that instead should read: “Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA, USA” which should be regarded as the final version by the reader.

We used an unmanned aircraft system (UAS) to lift and suspend distributed temperature sensing (DTS) technologies to observe the onset of an early morning transition from stable to unstably stratified atmospheric conditions. DTS employs a fiber optic cable interrogated by laser light, and uses the temperature dependent Raman scattering phenomenon and the speed of light to obtain a discrete spatial measurement of the temperature along the cable. The UAS/DTS combination yielded observations of temperature in the lower atmosphere with high resolution (1 s and 0.1 m) and extent (85 m) that revealed the detailed processes that occurred over a single morning transition. The experimental site was selected on the basis of previous experiments and long term data records; which indicate that diurnal boundary layer development and wind sectors are predictable and consistent. The data showed a complex interplay of motions that occur during the morning transition that resulted in propagation and growth of unstable wave modes. We observed a rapid cooling of the air aloft (layer above the strong vertical temperature gradient) layer directly after sunrise due to vertical mixing followed by an erosion of the strong gradient at the stable layer top. Midway through the transition, unstable wave modes were observed that are consistent with Kelvin–Helmholtz motions. These motions became amplified through the later stages of the transition.

The human visualization system is not optimally suited for fire detection. Smoke occlusion heavily limits flame visibility and low flames can be difficult to see. Thermal infrared (TIR) sensors mit...

Session Traversal Utilities for NAT (STUN) is a protocol that serves as a tool for other protocols in dealing with Network Address Translator (NAT) traversal. It can be used by an endpoint to determine the IP address and port allocated to it by a NAT. It can also be used to check connectivity between two endpoints, and as a keep-alive protocol to maintain NAT bindings. STUN works with many existing NATs, and does not require any special behavior from them. STUN is not a NAT traversal solution by itself. Rather, it is a tool to be used in the context of a NAT traversal solution. This document obsoletes RFC 5389.

We compared three existing ecoregional classification schemes (Bailey, Omernik, and World Wildlife Fund) with two derived schemes (Omernik Revised and Climate Zones) to explore their effectiveness in explaining species distributions and to better understand natural resource geography in the Klamath Region, USA. We analyzed presence/absence data derived from digital distribution maps for trees, amphibians, large mammals, small mammals, migrant birds, and resident birds using three statistical analyses of classification accuracy (Analysis of Similarity, Canonical Analysis of Principal Coordinates, and Classification Strength). The classifications were roughly comparable in classification accuracy, with Omernik Revised showing the best overall performance. Trees showed the strongest fidelity to the classifications, and large mammals showed the weakest fidelity. We discuss the implications for regional biogeography and describe how intermediate resolution ecoregional classifications may be appropria...

Weusedmapping-gradeglobalpositioningsystem(GPS)receiverstoexaminepost-processedhorizontalmeasurement accuraciesduring nine separate visitstosix sitesthat eachcontained 10 test points withina second-growth Douglas-firforest.OurprimaryobjectivewastocompareGPSaccuraciesresultingfromtwodifferentreceiverconfigurations that vary in productivityand accuracy. A secondaryobjective wasto determine howaccuracies would change with recordinginterval (whether we averaged 1, 5, 10, 30 or 60 positions). We also examined which environment-andGPS-relatedfactorsmostinfluencedGPSaccuracy.Rootmeansquareerror(RMSE)atthe95percent confidencelevel(RMSE95)usingthe‘default’GPSsetting(positiondilutionofprecision(PDOP):6;SNR39;minimum elevation158)was6.0 m,whileRMSE95using ‘maximum’settings(PDOP: 20;SNR33;minimumelevation:58)was 8.0 macrossallsitesandrecordingintervals.Usingdefaultsettings,RMSE95decreasedfrom7.3 mwhenaveraging one position to 4.4 m when averaging 60. For maximum settings, RMSE95 decreased from 9.1 to 6.5 m. Our best models selected basal area, dilution of precision and weather, but not terrain. When using default settings the averagewait timewas 55 sec whencollecting one position and 236 sec whenaveraging60. Using maximum settings,averagewaittimewas8 secwhencollectingoneposition,and74 secwhenaveraging60positions.Theerrors that we report are acceptable for many forestry applications. These results should help users to balance productivity with accuracy when using mapping-grade GPS receivers in second-growth Douglas-fir forests.

Airborne Light Detection and Ranging (LiDAR) has become a popular remote sensing technology to create digital terrain models and provide forest inventory information. However, little research has been done to investigate the accuracy of using scanning airborne LiDAR to perform road geomatics tasks common to forest engineering. We used airborne LiDAR to estimate existing forest road characteristics in support of a road assessment under four different canopy conditions. In estimating existing road centerlines, LiDAR data had a vertical root mean squared error (RMSE) of 0.28 m and a horizontal RMSE of 1.21 m. Road grades were estimated to within 1% slope of the value sampled in the field and horizontal curve radii were estimated with an average absolute error of 3.17 m. The results suggest that airborne LiDAR is an acceptable data source to estimate forest road centerlines and grades, but some caution should be used in estimating horizontal curve radii, particularly on sharp curves.

The rise of new real-time interactive services, in which consumers demand high subjective quality, makes it necessary to define new network mechanisms that can dynamically adapt to traffic variations. Cooperation between the different actors is required in order to adapt the traditional network infrastructure to these new traffic patterns while guaranteeing delay requirements. Thus, standardization is needed in order to make cooperation possible. A method for tunneling compressed multiplexed traffic flows (TCMTF) is proposed as an update to TCRTP, the current practice defined by the IETF for optimizing RTP flows. Some scenarios have been identified in which traffic optimization can be deployed, while granting resource usage fairness and good user experience. This proposal could be used in different application environments, such as operators' networks, Internet service providers, long distance transports, and game providers.

Wild forest fires are one of the greatest environmental disasters affecting forest resources. Along the coastal zone of the Mediterranean region in Turkey, forested areas are classified as first-degree, fire-sensitive areas. Every year, thousands of hectares of forests have been destroyed in Turkey. In this study, fire-access zones were determined in the Mediterranean forests of Turkey, by utilizing geographic information systems (GIS) technology. The effective reach distance of fire hoses from both sides of roads was considered in order to delineate fire-access zones. The effective reach distance can vary based on the technical capabilities and hydraulic capacity of fire trucks (minimum and maximum pressures on water pump); terrain structures (uphill, downhill and flat); and ground slope. These factors and their influences were studied in fire sensitive forest areas located in the eastern Mediterranean city of Kahramanmaraş in Turkey. First, terrain structures on both sides of the road network and ground-slope classes were determined based on GIS data layers. Then, fire access zones were delineated according to water pressure data, terrain structures, and ground-slope classes. The results indicated that 69.30 % of the forested areas were within the fire-access zones, while the rest of the forest was out of reach the fire hoses. The accessible areas were also calculated for forested areas with different fire-sensitivity degrees. The accessible areas were 69.59, 69.96, and 67.16 % for the forested areas that are sensitive to fires at the first, second, and third degrees, respectively. This finding has implications for the monitoring and management of fire threats in areas outside of the reach distance. The outside areas should receive extra attention and monitoring during the fire season so that fires are detected ahead of time and management has sufficient time to react. Besides, new roads should be considered for these areas in order to access more lands in a shorter amount of time. © 2016, Northeast Forestry University and Springer-Verlag Berlin Heidelberg.

We compared field based and airborne LiDAR-derived profile corridor measurements across forest canopy types and terrain ranging from 37% to 49% slope. Both LiDAR-derived DEM and raw LiDAR point elevations were compared to field data. Primary objectives included examining whether canopy type or terrain slope influenced LiDAR-derived profile measurements. A secondary objective included comparing cable logging payloads based on field measured profile elevations to payloads based on LiDAR-derived elevations. Average RMSE elevation errors were slightly lower for profile point to LiDAR DEM values (0.43 m) than profile point to nearest LiDAR elevation point (0.49 m) with differences being larger when sites within forest clearings were removed from analysis. No statistically significant relationship existed between field measured ground slopes and associated profile point and LiDAR DEM elevation differences but a mild correlation existed when LiDAR raw point elevation differences were compared. Our payload analysis determined the limiting payload distance and had consistent results across study sites. The DEM-based profile outperformed the nearest point profile by 5% on average. Results suggest that forest analysts should consider using the nearest LiDAR DEM value rather than the nearest LiDAR point elevation for terrain heights at discrete locations, particularly when forest canopy occludes locations of interest.

This paper develops a new measure of the spatial pattern of roads in an area, named the Road Network Agglomeration Index (RNAI), and explores the impact of this dimension of road networks on spatial patterns of conservation networks. RNAI is more spatially descriptive than road density measures used commonly in analyses of conservation patterns, and easier to calculate than some other metrics of road network characteristics. The paper uses both RNAI and road density in a case study, performing regression analyses to explore the drivers of fragmentation of California’s network of public and private conservation lands. RNAI emerges as a consistently strong indicator of the degree of fragmentation of the reserve network, complementing road density as a measure of features of road networks that affect the pattern of protected areas in a watershed. We also find that private conservation serves more often to increase rather than decrease agglomeration of the reserve network.

We examined the accuracy and reliability of consumer-grade global positioning system (GPS) receivers for tracking vehicles transporting forest biomass within several forested road systems. The road systems featured a range of forest canopy types on mountainous terrain. GPS receiver measurements were clearly influenced by forest canopy and varied among the receivers. Under mature forest canopy, the best average measurement accuracy was 5.9 m for one set of GPS receivers. The least favorable average accuracy in mature forest was 14.3 m for a different set of GPS receivers. Measurement accuracies generally increased on roads that featured less forest canopy, with considerable increases in accuracy in some cases. The consumer-grade GPS receivers we tested provided measurement accuracies that support forest biomass transportation applications, including transportation monitoring and planning, mapping forest road networks, and cataloging forest resource locations.

Elevation measurements are essential for many natural resource activities including hydrologic modeling, viewshed analysis, and forest road and trail engineering design. We collected elevation measurements with five identically configured mapping-grade global positioning system (GPS) receivers at two distinctly different test courses within a forest. Our primary objectives were to quantify the accuracy and reliability of GPS elevation measurements within two distinctly different environmental settings and to examine the influence of different data collection approaches. One test course was established within a forest clearing and had a generally unobstructed view of the overhead sky while the other course was mostly covered by forest canopy. We collected measurements using several different data groupings (1, 30, and 60s intervals) and calculated the elevation error of all GPS receiver measurements for both unprocessed and differentially corrected (processed) measurements. The average error was 2.7m (1.8 SD) for unprocessed and 0.4m (0.3 SD) for processed measurements when all GPS receiver data and point intervals (1, 30, and 60s) were combined at the open sky course. Average measurement error was 5.0m (4.6 SD) for unprocessed and 3.0m (2.8 SD) for processed measurements when grouping all GPS receiver data and point intervals (1, 30, and 60s) at the forest canopy course. Although the GPS receivers were identical in model and data collection parameters, we found statistically significant differences in elevation measurements between the receivers that we tested. We determined no statistical influence of 1, 30, and 60 point intervals on elevation measurement accuracy within each individual GPS receiver, regardless of measurement course or data processing. For many basic elevation measurement requirements, mapping-grade GPS receivers may provide an acceptable level of accuracy and reliability. Projects that require a high degree of elevation measurement accuracy may have to consider alternative methods, such as electronic digital measurement tools or manual means, of capturing elevation change across a forested landscape.

We collected measurements using five identical high-quality mapping-grade GPS receivers that were configured the same and collected data simultaneously in two distinctly different settings within a forest. Our primary objective was to determine whether measurement accuracies were different among the mapping-grade GPS receivers. A secondary objective was to determine whether measurement accuracies were different depending on whether receivers established their locations by taking a single 1-second measurement or by averaging 30 or 60 measurements. In the open-sky setting, where receivers had few obstructions overhead, we found that all five receivers recorded measurements with similar positional accuracies. Errors were lower when measurements were differentially corrected (postprocessed). We found an average error of 1.6 m for unprocessed data and an average error of 0.2 m for postprocessed data. Our results indicate that in open-sky conditions, all five receivers performed similarly when measurements were postprocessed. In addition, there was no significant difference in accuracy whether 1, 30, or 60 points were averaged, regardless of whether data were postprocessed. In the young-forest test course, examination of errors between receivers revealed that one receiver had significantly different errors compared with other receivers, which was likely the result of environmental influences on satellite signal strength and availability. We also found that measurement errors for all five receivers were significantly lower when measurements were postprocessed. On average, measurement errors were 5.9 m for unprocessed data and 1.4 m for postprocessed data. In analyzing individual receiver errors, no receiver had significantly different measurement errors whether 1, 30, or 60 measurements were recorded.

Network Address Translation (NAT) and Network Address and Port Translation (NAPT) are widely used to separate networks and share IPv4 addresses. They're valuable tools for network administrators and help with the imminent exhaustion of IPv4 address space and the transition to IPv6. This article surveys recent standardization efforts in this area.

With the increasing interest in the use of biomass for energy, conventional and alternative delivery systems are being evaluated for transporting biomass generated from harvest residuals on steep terrain in the Pacific Northwest. Conventional delivery systems include chipping or grinding of harvest residues (comminution) at the landing or a satellite yard in the forest and transporting the material with chip trucks to a power facility. To address some of the challenges of conventional methods of transporting biomass in steep terrain, chip van manufacturers have been making trailer modifications to increase vehicle maneuverability on forest roads. To evaluate the proper van configurations for implementing a successful biomass transportation system, planners should understand the limitations of the various chip van options. We present guidelines for designing new roads and evaluating existing road systems for chip truck access to forest residuals, as well as some practical field assessment procedures to evaluate accessibility on existing roads.

Wildfires have become more frequent and intense in recent years in the western United States. Previous studies have investigated the potential environmental and economic impacts of active management in burned forest landscapes. No previously published study, however, has considered wildlife requirements for snags while planning salvage logging operations in postburned landscapes. We examined the potential impacts of 19 snag retention strategies using cable-based yarding systems over a 3-year time period since burn. The strategies were based on current research recommendations, operational needs, and state and federal policies. Potential impacts on two cavity-nesting bird habitats and the feasibility of each strategy were examined. We found that most snag retention strategies generated net revenues per unit volume of merchantable wood greater than $70/m3 immediately after a burn and $60/m3 3 years after a burn. Those strategies that focused snag retention on smaller-diameter stems had the highest net revenue values and higher productivity rates. We also found that the strategy that removed all merchantable snags did not produce the highest revenue. In general, decreased yarding distance and a smaller yarding system (e.g., shovel loader) resulted in greater net revenue per unit volume with increased time since burn. The salvage strategy that provided the most favorable habitat for the two cavity-nesting birds left all snags standing in the half of the salvage unit farthest away from the yarder. Our findings indicate that it is possible to provide adequate cavity-nesting bird habitat and generate net revenue during fire salvage operations.

Elevation or height differences are necessary measurements for many forest operation activities. We rigorously examined the vertical measurement performance of five mapping-grade GPS receivers in three forest settings representing open-sky,young-forest, and closed-canopy conditions. The mapping-grade GPS receivers collected data simultaneously at each of the three forest settings and had different hardware and data-collection configurations, including internal and external antennas, and real-time differential corrections. We evaluated the influence of forest setting and postprocessed differential corrections on all GPS receiver measurements, including those that were collected with real-time differential corrections. We also compared the effect of 1-, 30-, and 60-point averaging intervals on vertical measurement accuracy. We found average vertical accuracies for unprocessed GPS receiver measurements of 0.9, 1.7, and 2.8 m in the open-sky, young-forest, and closed-canopy settings, respectively. The influence of data postprocessing was inconsistent under closed canopy and resulted in average vertical GPS accuracies of 0.2, 0.4, 3.3 m in open-canopy, young-forest, and closed-canopy settings, respectively. Different point averaging intervals did not result in statistically significant differences in vertical accuracies for either unprocessed or postprocessed GPS data.

Ulkemizde bolmeden cikarma calismalari %80’in uzerinde geleneksel yontemlerle yurutulmektedir. Bu metotlar sirasinda, insan ve hayvan gucu ile suruterek, atarak ya da kaydirilarak gerceklestirilen bolmeden cikarma calismalari, teknik, ekonomik, cevresel ve ergonomik acilardan problemlidir. Son yillarda sinirli sayida uygulanan plastik olukla tasima sistemi, cevre zararlarinin azaltilmasi yaninda, tasinan odun hammaddesindeki deger ve hacim kayiplarinin minimumda tutulmasi gibi onemli faydalar saglamaktadir. Bu calismada, daglik arazide kalin capli odun hammaddesinin yamac asagi kontrollu kaydirilmasi amaci ile tasinabilir vinc ile entegre edilmis bir oluk sistemi gelistirilmistir. Ayrica, sistemin daha hafif olmasi icin mevcut uygulamalarin aksine celik halat degil sentetik halat kullanilmistir. Sistem, Kahramanmaras Orman Isletme Mudurlugu, Cinarpinar Isletme Sefligi sinirlari icerisinde ornek bir uretim calismasinda test edilmistir. Calismada oluk sisteminin verimlilik analizleri gerceklestirilmis ve ekolojik etkileri incelenmistir. Yamac asagi kontrollu kaydirmada, en yuksek verim (10,01 m3 /saat) 36 m ve %70 egime sahip 4 no'lu oluk sisteminde bulunmustur. Oluk sisteminin ortalama verimi uzerinde etkili olan ana faktorlerin basinda tasinan odun hammaddelerini kontrollu kaydirma zamani gelmektedir. Kontrollu kaydirma operasyonlarinda kalan agac zararinin cok sinirli sayida kaldigi tespit edilmistir.

Ülkemizde bölmeden çıkarma çalışmaları %80’in üzerinde geleneksel yöntemlerle yürütülmektedir. Bu metotlar sırasında, insan ve hayvan gücü ile sürüterek, atarak ya da kaydırılarak gerçekleştirilen bölmeden çıkarma çalışmaları, teknik, ekonomik, çevresel ve ergonomik açılardan problemlidir. Son yıllarda sınırlı sayıda uygulanan plastik olukla taşıma sistemi, çevre zararlarının azaltılması yanında, taşınan odun hammaddesindeki değer ve hacim kayıplarının minimumda tutulması gibi önemli faydalar sağlamaktadır. Bu çalışmada, dağlık arazide kalın çaplı odun hammaddesinin yamaç aşağı kontrollü kaydırılması amacı ile taşınabilir vinç ile entegre edilmiş bir oluk sistemi geliştirilmiştir. Ayrıca, sistemin daha hafif olması için mevcut uygulamaların aksine çelik halat değil sentetik halat kullanılmıştır. Sistem, Kahramanmaraş Orman İşletme Müdürlüğü, Çınarpınar İşletme Şefliği sınırları içerisinde örnek bir üretim çalışmasında test edilmiştir. Çalışmada oluk sisteminin verimlilik analizleri gerçekleştirilmiş ve ekolojik etkileri incelenmiştir. Yamaç aşağı kontrollü kaydırmada, en yüksek verim (10,01 m3 /saat) 36 m ve %70 eğime sahip 4 no'lu oluk sisteminde bulunmuştur. Oluk sisteminin ortalama verimi üzerinde etkili olan ana faktörlerin başında taşınan odun hammaddelerini kontrollü kaydırma zamanı gelmektedir. Kontrollü kaydırma operasyonlarında kalan ağaç zararının çok sınırlı sayıda kaldığı tespit edilmiştir. Over 80% of wood extraction operations have been performed by conventional methods in Turkey. Conventional methods include skidding or sliding of logs mainly by man and animal power, which poses problems in terms of technical, economical, environmental, and ergonomic aspects. Skidding wood on plastic chutes has been implemented in limited numbers of logging applications in recent years, and provides important advantages such as reducing environmental damages and minimizing the value and volume loss of transported wood products. In this study, a chute system integrated with a mobile winch was developed for controlled sliding of large diameter logs downhill. In addition, synthetic ropes rather than steel cables were used to pull log products, resulting in a lower weight and more efficient extraction system. The system was tested on a sample wood production operation in Çınarpınar Forest Enterprise Chief of Kahramanmaraş Forest Enterprise Directorate. In the study, productivity analysis of chute system was performed and its ecological impacts were evaluated. During controlled sliding of logs downhill, the highest productivity (10.01 m3 /hour) was reached in the fourth chute system characterized as 36 m in length and 70% ground slope. One of the main factors that affected the productivity of chute system was the controlled sliding time of the logs. It was found that residual stand damage was very limited during controlled sliding operations.

We examined the microsite characteristics of 6,048 Douglas-fir seedlings at three regeneration sites in Washington state. Our objective was to determine the microsite characteristics that were most influential on seedling growth change over time. We analyzed microsite influences both individually and in concert with one another through regression-based techniques. Microsite parameters included soil impedance, topographic, and physical parameter measurements that were recorded at each seedling's location. Akaike's information criterion (AIC) was used to determine combinations of microsite parameters that were most strongly correlated with seedling growth. Multiparameter models explained between 15 and 39 percent of the variance in diameter growth. Prevalent terms from the strongest multiparameter models included soil penetration, log presence, stump presence, skid road presence, and topography. Individual microsite parameters for each regeneration site were also assessed for importance in explaining diameter growth using two additional methods. The first approach was to isolate the parameters that appeared in the strongest multiparameter models and to sum and contrast the AIC weights of all models in which they appeared. The second approach was to regress single parameters against seedling diameter growth. Results varied by site for both methods. AIC weight sums revealed that topographical depression and berms, the presences of logs and stumps, and soil penetration (pounds per square inch) as measured by a penetrometer were most influential, with values ranging from 0.31 (berm) to 0.82 (log). Regression analysis revealed that topographical depression, log presence, and soil penetration were significantly related to diameter growth, explaining between 6 and 29 percent of the variance in diameter growth. Combined results from the three regeneration sites suggest that preferred planting locations are near berms, in the transition zone associated with skid roads, and in soil that is neither too loose nor too compacted. Results from the Randle and Orting sites indicate that planting in topographical depressions should be avoided. Results from Orting indicate that seedlings should not be placed near logs, and Randle findings suggest not planting next to stumps.

Engineers Without Borders-USA (EWB-USA) consists of over 50 professional chapters throughout the country and over 100 student chapters at engineering universities. The goal of EWB-USA is to assist ...

Accuracy requirements for forested resource measurements can vary greatly depending on analysis and management objectives. Technologies that present efficiencies for reliable measurement collection may help organizations better meet data requirements. We tested the accuracy and reliability of a mapping-grade GPS in a variety of forested conditions in western Oregon. Our objectives were to measure the performance of a GPS operating in a standard configuration and also with real-time US Coast Guard Beacon signals. We also examined the influence of postfield differential corrections and the number of GPS points collected on measurement accuracy and reliability. We found measurement accuracies between 1 and 4 m from true position depending on the amount of canopy closure and the type of GPS configuration. Our results indicated that both standard-mode GPS and US Coast Guard Beacon signals can produce very accurate measurements in open-canopy conditions but are less reliable in young-forest conditions. Postprocessing of field measurements generally yielded improved measurements in young-forest settings but led to slightly reduced accuracies for US Coast Guard Beacon data collected in open-canopy settings. Our results also indicated that collecting a greater number of points does not necessarily lead to improved measurement accuracies. West. J. Appl. For. 21(4):222–227.

Microglia exist under physiological conditions in a resting state but become activated after neuronal injury. Recent studies have highlighted the reciprocal role of neurons in controlling both the number and activity of microglia. In this study, microglia derived from newborn rat cortices were cultured and activated by interferon-γ (IFNγ) treatment, then exposed to recombinant Sema3A or conditioned medium derived from stressed embryonic cortical neurons. We found that activation of microglia by IFNγ induced differential upregulation of the semaphorin receptors Plexin-A1 and Neuropilin-1. This result was confirmed by Northern blotting, reverse transcription-PCR, and Western blotting. Furthermore, recombinant Sema3A induced apoptosis of microglia when added to thein vitroculture, and a similar result was obtained on activated microglia when Sema3A was produced by stressed neurons. Using anin vivomodel of microglia activation by striatal injection of lipopolysaccharide demonstrated a corresponding upregulation of Plexin-A1 and Neuropilin-1 in activated microglia and enhanced production of Sema3A by stressed adult neurons. These results suggest a novel semaphorin-mediated mechanism of neuroprotection whereby stressed neurons can protect themselves from further damage by activated microglia.

Road sediment yields reaching streams over a twenty year period were modeled under two scenarios for a 4900 ha forest in the foothills of the Oregon Coast Range. In the "clustered" scenario all forest harvesting activity took place in the northern half of the forest. In the "dispersed" scenario the same level of forest harvesting activity was allocated to the full forest estate. Three spatial modeling packages were used: SPECTRUM was used to schedule the harvest settings over a 150 year period, NETWORK 2000 was used to determine which roads would be used during the first 20 years of harvest and how many truck loads would be transported over them, and SEDMODL2 was used to determine the road sediment yields likely to reach a stream. Concentrating the forest harvesting activity on half of the forest estate resulted in a 36% reduction in total road sediment yields when compared with dispersed forest harvesting activity. Fewer roads would generate sediment under the "clustered" scenario but traffic intensities on these roads would be greater, partially negating the sediment yield savings.

Our primary study objective was to test the accuracy and reliability of consumer-grade GPS receivers in a variety of landscape settings. We established three measurement testing courses in open sky, young forest, and closed canopy settings within a conifer-dominated forest in western Oregon and rigorously tested the positional accuracy of six different GPS. All units were produced by established GPS manufacturers. We found that performance varied, in some cases considerably, among units and appeared to be influenced by canopy cover and satellite availability. Among the top GPS performers, we determined that users could expect positional accuracies within approximately 5 m of true position in open sky settings, 7 m in young forest conditions, and 10 m under closed canopies.