You diagram can be have a copy error, or really have a design error.
Theses arduino relay shield is not good to use with Raspberry Pi.
You shield is one with three pins (vcc, in and gnd) on logic side?
Like this http://www.emartee.com/product/42055
This Shield use a PNP transistor to drive relay.
If is, this shield not work proper with raspberry pi.
Shield VCC is 5V, Raspberry PI is 3v3.
If connect Shield VCC on 5V, and IN to some GPIO, relay is activated all times.
If connect Shield VCC to 3v3, and IN to GPIO, relay can apparently appears to work, but is not ideal. And, can reset raspberry pi due noise, spike, and drop on 3v3 line.
To make it work proper, need a extra circuit, a NPN (2N2222) transistor and a resistor (2k2). Connect emitter to GND, collector to IN, base to resistor, and resistor to GPIO. Shield VCC to 5V direct from PSU.